A systematic review of thromboembolic complications and outcomes in hospitalised COVID-19 patients

Thromboembolic (TE) complications [myocardial infarction (MI), stroke, deep vein thrombosis (DVT), and pulmonary embolism (PE)] are common causes of mortality in hospitalised COVID-19 patients. Therefore, this review was undertaken to explore the incidence of TE complications and mortality associated with TE complications in hospitalised COVID-19 patients from different studies. A literature search was performed using ScienceDirect and PubMed databases using the MeSH term search strategy of "COVID-19", "thromboembolic complication", "venous thromboembolism", "arterial thromboembolism", "deep vein thrombosis", "pulmonary embolism", "myocardial infarction", "stroke", and "mortality". There were 33 studies included in this review. Studies have revealed that COVID-19 patients tend to develop venous thromboembolism (PE:1.0-40.0% and DVT:0.4-84%) compared to arterial thromboembolism (stroke:0.5-15.2% and MI:0.8-8.7%). Lastly, the all-cause mortality of COVID-19 patients ranged from 4.8 to 63%, whereas the incidence of mortality associated with TE complications was between 5% and 48%. A wide range of incidences of TE complications and mortality associated with TE complications can be seen among hospitalized COVID-19 patients. Therefore, every patient should be assessed for the risk of thromboembolic complications and provided with an appropriate thromboprophylaxis management plan tailored to their individual needs.

Thromboembolic events, major bleeding and mortality in essential thrombocythaemia and polycythaemia vera-A matched nationwide population-based study

Thromboembolic events and bleeding are known complications in essential thrombocythaemia (ET) and polycythaemia vera (PV). Using multiple Swedish health care registers, we assessed the rate of arterial and venous events, major bleeding, all-cause stroke and all-cause mortality in ET and PV compared to matched controls. For each patient with ET (n = 3141) and PV (n = 2604), five matched controls were randomly selected. In total, 327 and 405 arterial or venous events were seen in the group of ET and PV patients respectively. Compared to corresponding controls, the rate of venous thromboembolism, major bleeding and all-cause mortality per 100 treatment years was significantly increased among both ET (0.63, 0.79 and 3.70) and PV patients (0.94, 1.20 and 4.80). The PV patients also displayed a significantly higher rate of arterial events and all-cause stroke compared to controls. When dividing the cohort into age groups, we found a significantly higher rate of arterial and venous events in all age groups of PV patients, and the rate of all-cause mortality was significantly higher in both ET and PV patients in all ages above the age of 50. This study confirms that PV and ET are diseases truly marked by thromboembolic complications and bleeding.

Influence of thromboembolic events in the prognosis of COVID-19 hospitalized patients. Results from a cross sectional study

BACKGROUND

COVID-19 may predispose to both venous and arterial thromboembolism event (TEE). Reports on the prevalence and prognosis of thrombotic complications are still emerging.

OBJECTIVE

To describe the rate of TEE complications and its influence in the prognosis of hospitalized patients with COVID-19 after a cross-sectional study.

METHODS

We evaluated the prevalence of TEE and its relationship with in-hospital death among hospitalized patients with COVID-19 who were admitted between 1st March to 20th April 2020 in a multicentric network of sixteen Hospitals in Spain. TEE was defined by the occurrence of venous thromboembolism (VTE), acute ischemic stroke (AIS), systemic arterial embolism or myocardial infarction (MI).

RESULTS

We studied 1737 patients with proven COVID-19 infection of whom 276 died (15.9%). TEE were presented in 64 (3.7%) patients: 49 (76.6%) patients had a VTE, 8 (12.5%) patients had MI, 6 (9.4%%) patients had AIS, and one (1.5%) patient a thrombosis of portal vein. TEE patients exhibited a diffuse profile: older, high levels of D-dimer protein and a tendency of lower levels of prothrombin. The multivariate regression models, confirmed the association between in-hospital death and age (odds ratio [OR] 1.12 [95% CI 1.10-1.14], p<0.001), diabetes (OR 1.49 [95% CI 1.04-2.13], p = 0.029), chronic obstructive pulmonary disease (OR 1.61 [95% CI 1.03-2.53], p = 0.039), ICU care (OR 9.39 [95% CI 5.69-15.51], p<0.001), and TTE (OR 2.24 [95% CI 1.17-4.29], p = 0.015).

CONCLUSIONS

Special attention is needed among hospitalized COVID-19 patients with TTE and other comorbidities as they have an increased risk of in-hospital death.

Direct oral anticoagulants and warfarin in patients with cirrhosis: a comparison of outcomes

Anticoagulation management in patients with cirrhosis presents several challenges as a result of alterations in hemostasis. Historically vitamin k antagonists and low molecular weight heparins have been the agents of choice in this patient population. Direct oral anticoagulants (DOACs) may provide an alternative to traditional anticoagulant therapy. To evaluate the rate of major bleeding among patients receiving DOACs or warfarin with cirrhosis. A retrospective, observational, cohort study of adult patients admitted between January 2012 and July 2018 with diagnosis of cirrhosis receiving anticoagulation with DOAC or warfarin therapy was performed. Patients were stratified based on the receipt of a DOAC or warfarin. The primary endpoint was incidence of major bleeding at 90 days. Secondary endpoints included stroke or embolic event at 90 days as well as rehospitalization and mortality at 1 year. One hundred sixty-seven patients were included for analysis; of which 110 received warfarin and 57 received a DOAC. The most commonly used DOAC was apixaban (52.6%) followed by rivaroxaban (45.6%) and dabigratran (1.8%). The incidence of major bleeding was similar between warfarin and DOAC groups (9.1% vs. 5.2% p = 0.381). No difference in the rate of stroke or recurrent embolic event at 90 days was identified between the two groups (0% vs. 1.58% p = 0.341; 1.8% vs. 1.8% p = 0.731). In conclusion DOACs appear to be a safe alternative to warfarin in patients with mild to moderate cirrhosis. Further studies are warranted to confirm these findings.

Anticoagulation versus placebo for heart failure in sinus rhythm

BACKGROUND

People with chronic heart failure (HF) are at risk of thromboembolic events, including stroke, pulmonary embolism, and peripheral arterial embolism; coronary ischaemic events also contribute to the progression of HF. The use of long-term oral anticoagulation is established in certain populations, including people with HF and atrial fibrillation (AF), but there is wide variation in the indications and use of oral anticoagulation in the broader HF population.

OBJECTIVES

To determine whether long-term oral anticoagulation reduces total deaths and stroke in people with heart failure in sinus rhythm.

SEARCH METHODS

We updated the searches in CENTRAL, MEDLINE, and Embase in March 2020. We screened reference lists of papers and abstracts from national and international cardiovascular meetings to identify unpublished studies. We contacted relevant authors to obtain further data. We did not apply any language restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCT) comparing oral anticoagulants with placebo or no treatment in adults with HF, with treatment duration of at least one month. We made inclusion decisions in duplicate, and resolved any disagreements between review authors by discussion, or a third party.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion, and assessed the risks and benefits of antithrombotic therapy by calculating odds ratio (OR), accompanied by the 95% confidence intervals (CI).

MAIN RESULTS

We identified three RCTs (5498 participants). One RCT compared warfarin, aspirin, and no antithrombotic therapy, the second compared warfarin with placebo in participants with idiopathic dilated cardiomyopathy, and the third compared rivaroxaban with placebo in participants with HF and coronary artery disease. We pooled data from the studies that compared warfarin with a placebo or no treatment. We are uncertain if there is an effect on all-cause death (OR 0.66, 95% CI 0.36 to 1.18; 2 studies, 324 participants; low-certainty evidence); warfarin may increase the risk of major bleeding events (OR 5.98, 95% CI 1.71 to 20.93, NNTH 17). 2 studies, 324 participants; low-certainty evidence). None of the studies reported stroke as an individual outcome. Rivaroxaban makes little to no difference to all-cause death compared with placebo (OR 0.99, 95% CI 0.87 to 1.13; 1 study, 5022 participants; high-certainty evidence). Rivaroxaban probably reduces the risk of stroke compared to placebo (OR 0.67, 95% CI 0.47 to 0.95; NNTB 101; 1 study, 5022 participants; moderate-certainty evidence), and probably increases the risk of major bleeding events (OR 1.65, 95% CI 1.17 to 2.33; NNTH 79; 1 study, 5008 participants; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

Based on the three RCTs, there is no evidence that oral anticoagulant therapy modifies mortality in people with HF in sinus rhythm. The evidence is uncertain if warfarin has any effect on all-cause death compared to placebo or no treatment, but it may increase the risk of major bleeding events. There is no evidence of a difference in the effect of rivaroxaban on all-cause death compared to placebo. It probably reduces the risk of stroke, but probably increases the risk of major bleedings. The available evidence does not support the routine use of anticoagulation in people with HF who remain in sinus rhythm.

Acute and Life-threatening Complications in Cushing Syndrome: Prevalence, Predictors, and Mortality

CONTEXT

Cushing syndrome (CS) results in significant morbidity and mortality.

OBJECTIVE

To study acute and life-threatening complications in patients with active CS.

METHODS

We performed a retrospective cohort study using inpatient and outpatient records of patients with CS in a tertiary center. A total of 242 patients with CS were included, including 213 with benign CS (pituitary n = 101, adrenal n = 99, ectopic n = 13), and 29 with malignant disease. We collected acute complications necessitating hospitalization, from appearance of first symptoms of hypercortisolism until 1 year after biochemical remission. Mortality data were obtained from the national registry. Baseline factors relating to and predicting acute complications were tested using uni- and multivariate analysis.

RESULTS

The prevalence of acute complications was 62% in patients with benign pituitary CS, 40% in patients with benign adrenal CS, and 100% in patients with ectopic CS. Complications observed in patients with benign CS included infections (25%), thromboembolic events (17%), hypokalemia (13%), hypertensive crises (9%), cardiac arrhythmias (5%), and acute coronary events (3%). Among these patients, 23% had already been hospitalized for acute complications before CS was suspected, and half of complications occurred after the first surgery. Glycated hemoglobin (HbA1c) and 24-hour urinary free cortisol positively correlated with the number of acute complications per patient. Patients with malignant disease had significantly higher rates of acute complications. Mortality during the observation period was 2.8% and 59% in benign and malignant CS, respectively.

CONCLUSIONS

This analysis highlights the whole spectrum of acute and life-threatening complications in CS, and their high prevalence even before disease diagnosis and after successful surgery.

Use of low-molecular weight heparin, transfusion and mortality in COVID-19 patients not requiring ventilation

It is still debated whether prophylactic doses of low-molecular- weight heparin (LMWH) are always effective in preventing Venous Thromboembolism (VTE) and mortality in COVID-19. Furthermore, there is paucity of data for those patients not requiring ventilation. We explored mortality and the safety/efficacy profile of LMWH in a cohort of Italian patients with COVID-19 who did not undergo ventilation. From the initial cohort of 422 patients, 264 were enrolled. Most (n = 156, 87.7%) received standard LMWH prophylaxis during hospitalization, with no significant difference between medical wards and Intensive Care Unit (ICU). Major or not major but clinically relevant hemorrhages were recorded in 13 (4.9%) patients: twelve in those taking prophylactic LMWH and one in a patient taking oral anticoagulants (p: n.s.). Thirty-nine patients (14.8%) with median age 75 years. were transfused. Hemoglobin (Hb) at admission was significantly lower in transfused patients and Hb at admission inversely correlated with the number of red blood cells units transfused (p < 0.001). In-hospital mortality occurred in 76 (28.8%) patients, 46 (24.3%) of whom admitted to medical wards. Furthermore, Hb levels at admittance were significantly lower in fatalities (g/dl 12.3; IQR 2.4 vs. 13.3; IQR 2.8; Mann–Whitney U-test; p = 0.001). After the exclusion of patients treated by LMWH intermediate or therapeutic doses (n = 32), the logistic regression showed that prophylaxis significantly and independently reduced mortality (OR 0.31, 95% CI 0.13–0.85). Present data show that COVID-19 patients who do not require ventilation benefit from prophylactic doses of LMWH.

Tranexamic acid should be avoided for acute gastrointestinal bleeds

Overview of: The HALT-IT Trial Collaborators. Effects of a high-dose 24-h infusion of tranexamic acid on death and thromboembolic events in patients with acute gastrointestinal bleeding (HALT-IT): an international randomised, double-blind, placebo-controlled trial. Lancet 2020; 395:1927-36.

Clinical Characteristics of Stroke with COVID-19: A Systematic Review and Meta-Analysis

BACKGROUND

The coronavirus disease 2019 (COVID-19) potentially increases the risk of thromboembolism and stroke. Numerous case reports and retrospective cohort studies have been published with mixed characteristics of COVID-19 patients with stroke regarding age, comorbidities, treatment, and outcome. We aimed to depict the frequency and clinical characteristics of COVID-19 patients with stroke.

METHODS

PubMed and EMBASE were searched on June 10, 2020, to investigate COVID-19 and stroke through retrospective cross-sectional studies, case series/reports according to PRISMA guidelines. Study-specific estimates were combined using one-group meta-analysis in a random-effects model.

RESULTS

10 retrospective cohort studies and 16 case series/reports were identified including 183 patients with COVID-19 and stroke. The frequency of detected stroke in hospitalized COVID-19 patients was 1.1% ([95% confidential interval (CI)]: [0.6-1.6], I2 = 62.9%). Mean age was 66.6 ([58.4-74.9], I2 = 95.1%), 65.6% was male (61/93 patients). Mean days from symptom onset of COVID-19 to stroke was 8.0 ([4.1-11.9], p< 0.001, I2 = 93.1%). D-dimer was 3.3 μg/mL ([1.7-4.9], I2 = 86.3%), and cryptogenic stroke was most common as etiology at 50.7% ([31.0-70.4] I2 = 64.1%, 39/71patients). Case fatality rate was 44.2% ([27.9-60.5], I2 = 66.7%, 40/100 patients).

CONCLUSIONS

This systematic review assessed the frequency and clinical characteristics of stroke in COVID-19 patients. The frequency of detected stroke in hospitalized COVID-19 patients was 1.1% and associated with older age and stroke risk factors. Frequent cryptogenic stroke and elevated d-dimer level support increased risk of thromboembolism in COVID-19 associated with high mortality. Further study is needed to elucidate the pathophysiology and prognosis of stroke in COVID-19 to achieve most effective care for this population.

Antiplatelet and anticoagulant agents for secondary prevention of stroke and other thromboembolic events in people with antiphospholipid syndrome

BACKGROUND

Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterized by arterial or venous thrombosis (or both), and/or pregnancy morbidity in association with the presence of antiphospholipid antibodies. The prevalence of APS is estimated at 40 to 50 cases per 100,000 people. The most common sites of thrombosis are cerebral arteries and deep veins of the lower limbs. People with a definite APS diagnosis have an increased lifetime risk of recurrent thrombotic events.

OBJECTIVES

To assess the effects of antiplatelet (AP) or anticoagulant agents, or both, for the secondary prevention of recurrent thrombosis, particularly ischemic stroke, in people with APS.

SEARCH METHODS

We last searched the MEDLINE, Embase, CENTRAL, Cochrane Stroke Group Trials Register, and ongoing trials registers on 22 November 2019. We checked reference lists of included studies, systematic reviews, and practice guidelines. We also contacted experts in the field.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that evaluated any anticoagulant or AP agent, or both, in the secondary prevention of thrombosis in people with APS, according to the criteria valid when the study took place. We did not include studies specifically addressing women with obstetrical APS.

DATA COLLECTION AND ANALYSIS

Pairs of review authors independently worked on each step of the review, following Cochrane methods. We summarized the evidence using the GRADE approach.

MAIN RESULTS

We identified eight studies including 811 participants that compared different AP or anticoagulant agents. NOAC (non-VKA oral anticoagulant: rivaroxaban 15 or 20 mg/d) versus standard-dose VKA (vitamin K antagonist: warfarin at moderate International Normalized Ratio [INR] - 2.5) or adjusted [INR 2.0-3.0] dose): In three studies there were no differences in any thromboembolic event (including death) and major bleeding (moderate-certainty evidence), but an increased risk of stroke (risk ratio [RR] 14.13, 95% confidence interval [CI] 1.87 to 106.8; moderate-certainty evidence). One of the studies reported a small benefit of rivaroxaban in terms of quality of life at 180 days measured as health state on Visual Analogue Scale (mean difference [MD] 7 mm, 95% CI 2.01 to 11.99; low-certainty evidence), but not measured as health utility on a scale from 0 to 1 (MD 0.04, 95% CI -0.02 to 0.10; low-certainty evidence). High-dose VKA (warfarin with a target INR of 3.1 to 4.0 [mean 3.3] or 3.5 [mean 3.2]) versus standard-dose VKA (warfarin with a target INR of 2.0 to 3.0 [mean 2.3] or 2.5 [mean 2.5]): In two studies there were no differences in the rates of thrombotic events and major bleeding (RR 2.22, 95% CI 0.79 to 6.23, low-certainty evidence), but an increased risk of minor bleeding in one study during a mean of 3.4 years (standard deviation [SD] 1.2) of follow-up (RR 2.55, 95% CI 1.07 to 6.07). In both trials there was evidence of a higher risk of any bleeding (hazard ratio [HR] 2.03 95% CI 1.12 to 3.68; low-certainty evidence) in the high-dose VKA group, and for this outcome (any bleeding) the incidence is not different, only the time to event is showing an effect. Standard-dose VKA plus a single AP agent (warfarin at a target INR of 2.0 to 3.0 plus aspirin 100 mg/d) versus standard-dose VKA (warfarin at a target INR of 2.0 to 3.0): One high-risk-of-bias study showed an increased risk of any thromboembolic event with combined treatment (RR 2.14, 95% CI 1.04 to 4.43; low-certainty evidence) and reported on major bleeding with five cases in the combined treatment group and one case in the standard-dose VKA treatment group, resulting in RR 7.42 (95% CI 0.91 to 60.7; low-certainty evidence) and no differences for secondary outcomes (very low- to low-certainty evidence). Single/dual AP agent and standard-dose VKA (pooled results): Two high-risk-of-bias studies compared a combination of AP and VKA (aspirin 100 mg/d plus warfarin or unspecified VKA at a target INR of 2.0 to 3.0 or 2.0 to 2.5) with a single AP agent (aspirin 100 mg/d), but did not provide any conclusive evidence regarding the effects of those drugs in people with APS (very low-certainty evidence). One of the above-mentioned studies was a three-armed study that compared a combination of AP and VKA (aspirin 100 mg/d plus warfarin at a target INR of 2.0 to 2.5) with dual AP therapy (aspirin 100 mg/d plus cilostazol 200 mg/d) and dual AP therapy (aspirin 100 mg/d plus cilostazol 200 mg/d) versus a single AP treatment (aspirin 100 mg/d). This study reported on stroke (very low-certainty evidence) but did not report on any thromboembolic events, major bleeding, or any secondary outcomes. We identified two ongoing studies and three studies are awaiting classification.

AUTHORS' CONCLUSIONS

The evidence identified indicates that NOACs compared with standard-dose VKAs may increase the risk of stroke and do not appear to alter the risk of other outcomes (moderate-certainty evidence). Using high-dose VKA versus standard-dose VKA did not alter the risk of any thromboembolic event or major bleeding but may increase the risk of any form of bleeding (low-certainty evidence). Standard-dose VKA combined with an AP agent compared with standard-dose VKA alone may increase the risk of any thromboembolic event and does not appear to alter the risk of major bleeding or other outcomes (low-certainty evidence). The evidence is very uncertain about the benefit or harm of using standard-dose VKA plus AP agents versus single or dual AP therapy, or dual versus single AP therapy, for the secondary prevention of recurrent thrombosis in people with APS (very low-certainty evidence).

Prophylactic anticoagulants for people hospitalised with COVID-19

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a serious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The primary manifestation is respiratory insufficiency that can also be related to diffuse pulmonary microthrombosis in people with COVID-19. This disease also causes thromboembolic events, such as pulmonary embolism, deep venous thrombosis, arterial thrombosis, catheter thrombosis, and disseminated intravascular coagulopathy. Recent studies have indicated a worse prognosis for people with COVID-19 who developed thromboembolism. Anticoagulants are medications used in the prevention and treatment of venous or arterial thromboembolic events. Several drugs are used in the prophylaxis and treatment of thromboembolic events, such as heparinoids (heparins or pentasaccharides), vitamin K antagonists and direct anticoagulants. Besides their anticoagulant properties, heparinoids have an additional anti-inflammatory potential, that may affect the clinical evolution of people with COVID-19. Some practical guidelines address the use of anticoagulants for thromboprophylaxis in people with COVID-19, however, the benefit of anticoagulants for people with COVID-19 is still under debate.

OBJECTIVES

To assess the effects of prophylactic anticoagulants versus active comparator, placebo or no intervention, on mortality and the need for respiratory support in people hospitalised with COVID-19.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, LILACS and IBECS databases, the Cochrane COVID-19 Study Register and medRxiv preprint database from their inception to 20 June 2020. We also checked reference lists of any relevant systematic reviews identified and contacted specialists in the field for additional references to trials.

SELECTION CRITERIA

Randomised controlled trials (RCTs), quasi-RCTs, cluster-RCTs and cohort studies that compared prophylactic anticoagulants (heparin, vitamin K antagonists, direct anticoagulants, and pentasaccharides) versus active comparator, placebo or no intervention for the management of people hospitalised with COVID-19. We excluded studies without a comparator group. Primary outcomes were all-cause mortality and need for additional respiratory support. Secondary outcomes were mortality related to COVID-19, deep vein thrombosis (DVT), pulmonary embolism, major bleeding, adverse events, length of hospital stay and quality of life.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures. We used ROBINS-I to assess risk of bias for non-randomised studies (NRS) and GRADE to assess the certainty of evidence. We reported results narratively.

MAIN RESULTS

We identified no RCTs or quasi-RCTs that met the inclusion criteria. We included seven retrospective NRS (5929 participants), three of which were available as preprints. Studies were conducted in China, Italy, Spain and the USA. All of the studies included people hospitalised with COVID-19, in either intensive care units, hospital wards or emergency departments. The mean age of participants (reported in 6 studies) ranged from 59 to 72 years. Only three included studies reported the follow-up period, which varied from 8 to 35 days. The studies did not report on most of our outcomes of interest: need for additional respiratory support, mortality related to COVID-19, DVT, pulmonary embolism, adverse events, and quality of life. Anticoagulants (all types) versus no treatment (6 retrospective NRS, 5685 participants) One study reported a reduction in all-cause mortality (adjusted odds ratio (OR) 0.42, 95% confidence interval (CI) 0.26 to 0.66; 2075 participants). One study reported a reduction in mortality only in a subgroup of 395 people who required mechanical ventilation (hazard ratio (HR) 0.86, 95% CI 0.82 to 0.89). Three studies reported no differences in mortality (adjusted OR 1.64, 95% CI 0.92 to 2.92; 449 participants; unadjusted OR 1.66, 95% CI 0.76 to 3.64; 154 participants and adjusted risk ratio (RR) 1.15, 95% CI 0.29 to 2.57; 192 participants). One study reported zero events in both intervention groups (42 participants). The overall risk of bias for all-cause mortality was critical and the certainty of the evidence was very low. One NRS reported bleeding events in 3% of the intervention group and 1.9% of the control group (OR 1.62, 95% CI 0.96 to 2.71; 2773 participants; low-certainty evidence). Therapeutic-dose anticoagulants versus prophylactic-dose anticoagulants (1 retrospective NRS, 244 participants) The study reported a reduction in all-cause mortality (adjusted HR 0.21, 95% CI 0.10 to 0.46) and a lower absolute rate of death in the therapeutic group (34.2% versus 53%). The overall risk of bias for all-cause mortality was serious and the certainty of the evidence was low. The study also reported bleeding events in 31.7% of the intervention group and 20.5% of the control group (OR 1.8, 95% CI 0.96 to 3.37; low-certainty evidence). Ongoing studies We found 22 ongoing studies in hospital settings (20 RCTs, 14,730 participants; 2 NRS, 997 participants) in 10 different countries (Australia (1), Brazil (1), Canada (2), China (3), France (2), Germany (1), Italy (4), Switzerland (1), UK (1) and USA (6)). Twelve ongoing studies plan to report mortality and six plan to report additional respiratory support. Thirteen studies are expected to be completed in December 2020 (6959 participants), eight in July 2021 (8512 participants), and one in December 2021 (256 participants). Four of the studies plan to include 1000 participants or more.

AUTHORS' CONCLUSIONS

There is currently insufficient evidence to determine the risks and benefits of prophylactic anticoagulants for people hospitalised with COVID-19. Since there are 22 ongoing studies that plan to evaluate more than 15,000 participants in this setting, we will add more robust evidence to this review in future updates.

Comparison of Antithrombotic Strategies in Chinese Patients in Sinus Rhythm after Bioprosthetic Mitral Valve Replacement: Early Outcomes from a Multicenter Registry in China

OBJECTIVES

To compare antithrombotic strategies in Chinese patients undergoing bioprosthetic mitral valve implantation discharged in normal sinus rhythm.

METHODS

At 28 hospitals in China, 1603 patients were followed for 2991.5 person-years. Adverse event and death rates during five postoperative time intervals (≤ 30, 31-90, 91-180, 181-365, and 366-730 days) were calculated in patients administered warfarin, aspirin, warfarin + aspirin, or neither treatment.

RESULTS

Thromboembolic and hemorrhagic events occurred in 22 (0.74/100 patient-years, 95%CI 0.43-1.05) and 28 (0.94/100 patient-years, 95%CI 0.59-1.29) patients, respectively. In the first 3 months post-surgery, warfarin-treated patients had significantly lower rates of thromboembolic events than the aspirin or untreated groups (P = 0.01, P<0.01), and a significantly lower risk of bleeding than the aspirin + warfarin group (P = 0.02). From 91 to 180 days post-surgery, thromboembolism risk was significantly lower in warfarin-treated patients relative to the aspirin-treated and untreated patients (P = 0.04, P = 0.04), but bleeding and overall adverse event rates were similar (P = 1.00). From 181 to 365 days, thromboembolic event rates did not differ significantly between the untreated and anticoagulant-treated groups (P = 1.00).

CONCLUSION

Warfarin is the most effective intervention for preventing thromboembolism within 6 months post-bioprosthetic MVR surgery in Chinese patients in sinus rhythm. After 6 months, further warfarin therapy was unnecessary, and aspirin should not be routinely administered.

A Controlled Trial of Rivaroxaban after Transcatheter Aortic-Valve Replacement

BACKGROUND

Whether the direct factor Xa inhibitor rivaroxaban can prevent thromboembolic events after transcatheter aortic-valve replacement (TAVR) is unclear.

METHODS

We randomly assigned 1644 patients without an established indication for oral anticoagulation after successful TAVR to receive rivaroxaban at a dose of 10 mg daily (with aspirin at a dose of 75 to 100 mg daily for the first 3 months) (rivaroxaban group) or aspirin at a dose of 75 to 100 mg daily (with clopidogrel at a dose of 75 mg daily for the first 3 months) (antiplatelet group). The primary efficacy outcome was the composite of death or thromboembolic events. The primary safety outcome was major, disabling, or life-threatening bleeding. The trial was terminated prematurely by the data and safety monitoring board because of safety concerns.

RESULTS

After a median of 17 months, death or a first thromboembolic event (intention-to-treat analysis) had occurred in 105 patients in the rivaroxaban group and in 78 patients in the antiplatelet group (incidence rates, 9.8 and 7.2 per 100 person-years, respectively; hazard ratio with rivaroxaban, 1.35; 95% confidence interval [CI], 1.01 to 1.81; P = 0.04). Major, disabling, or life-threatening bleeding (intention-to-treat analysis) had occurred in 46 and 31 patients, respectively (4.3 and 2.8 per 100 person-years; hazard ratio, 1.50; 95% CI, 0.95 to 2.37; P = 0.08). A total of 64 deaths occurred in the rivaroxaban group and 38 in the antiplatelet group (5.8 and 3.4 per 100 person-years, respectively; hazard ratio, 1.69; 95% CI, 1.13 to 2.53).

CONCLUSIONS

In patients without an established indication for oral anticoagulation after successful TAVR, a treatment strategy including rivaroxaban at a dose of 10 mg daily was associated with a higher risk of death or thromboembolic complications and a higher risk of bleeding than an antiplatelet-based strategy. (Funded by Bayer and Janssen Pharmaceuticals; GALILEO ClinicalTrials.gov number, NCT02556203.).

Reduced Leaflet Motion after Transcatheter Aortic-Valve Replacement

BACKGROUND

Subclinical leaflet thickening and reduced leaflet motion of bioprosthetic aortic valves have been documented by four-dimensional computed tomography (CT). Whether anticoagulation can reduce these phenomena after transcatheter aortic-valve replacement (TAVR) is not known.

METHODS

In a substudy of a large randomized trial, we randomly assigned patients who had undergone successful TAVR and who did not have an indication for long-term anticoagulation to a rivaroxaban-based antithrombotic strategy (rivaroxaban [10 mg] plus aspirin [75 to 100 mg] once daily) or an antiplatelet-based strategy (clopidogrel [75 mg] plus aspirin [75 to 100 mg] once daily). Patients underwent evaluation by four-dimensional CT at a mean (±SD) of 90±15 days after randomization. The primary end point was the percentage of patients with at least one prosthetic valve leaflet with grade 3 or higher motion reduction (i.e., involving >50% of the leaflet). Leaflet thickening was also assessed.

RESULTS

A total of 231 patients were enrolled. At least one prosthetic valve leaflet with grade 3 or higher motion reduction was found in 2 of 97 patients (2.1%) who had scans that could be evaluated in the rivaroxaban group, as compared with 11 of 101 (10.9%) in the antiplatelet group (difference, -8.8 percentage points; 95% confidence interval [CI], -16.5 to -1.9; P = 0.01). Thickening of at least one leaflet was observed in 12 of 97 patients (12.4%) in the rivaroxaban group and in 33 of 102 (32.4%) in the antiplatelet group (difference, -20.0 percentage points; 95% CI, -30.9 to -8.5). In the main trial, the risk of death or thromboembolic events and the risk of life-threatening, disabling, or major bleeding were higher with rivaroxaban (hazard ratios of 1.35 and 1.50, respectively).

CONCLUSIONS

In a substudy of a trial involving patients without an indication for long-term anticoagulation who had undergone successful TAVR, a rivaroxaban-based antithrombotic strategy was more effective than an antiplatelet-based strategy in preventing subclinical leaflet-motion abnormalities. However, in the main trial, the rivaroxaban-based strategy was associated with a higher risk of death or thromboembolic complications and a higher risk of bleeding than the antiplatelet-based strategy. (Funded by Bayer; GALILEO-4D ClinicalTrials.gov number, NCT02833948.).

The role of a specialist bridging service. A New Zealand prospective study of 600 patients

BACKGROUND

A proposition for the Wellington hospital thrombosis service to manage periprocedure anticoagulation bridging was made after a number of cancellations and key incidents were caused by lack of a consistent management approach. We provided individual bridging assessments, with implementation, communication, and education. The only funded anticoagulants in New Zealand at that time were dabigatran, warfarin, and enoxaparin.

METHODS

On initiation of the bridging service, we prospectively collected data on 600 consecutive patients referred to the periprocedure bridging service between May 2015 and February 2017. We recorded the 30-day major bleeding events, thrombotic events, and related mortality. We followed the patients up for 30 days postprocedure. As part of this process, we ensured optimal transition back to their initial anticoagulant.

CONCLUSION

We found low rates of major bleeding 1.9% and thrombosis 0.8% at day 30 comparable to randomized controlled trials. Of the 222 patients taking dabigatran experienced no major bleeding events. We believe using a specialist coagulation service is optimal to ensure surgery can proceed safely.

[Maternal deaths in Sweden: Diagnostics and clinical management could be improved]

MM-ARG, the Swedish maternal maternity mortality group within SFOG (Swedish Society of Obstetrics and Gynecology) has, since 2008, surveyed and analysed maternal deaths in Sweden with the aim to find and give feedback on lessons learned to the medical professions.  MM-ARG consists of obstetricians, midwives and anesthetists and the strength of the working model is that the profession itself takes responsibility for the scrutiny.  A summary of 67 known maternal deaths from 2007‒2017 is presented. Direct causes of death are dominated by hypertensive disease/preeclampsia, followed by thromboembolic disease, sepsis and obstetric bleeding. Indirect death, where a known or unknown underlying disease is exacerbated by pregnancy, is dominated by cardiovascular disease. This review shows that the diagnostics and clinical management could be improved. Besides obstetrics/gynecology, maternal mortality affects other specialties and thus holds important lessons to many.

Antithrombotic Therapy and Cardiovascular Outcomes After Transcatheter Aortic Valve Replacement in Patients With Atrial Fibrillation

OBJECTIVES

The study sought to determine the patterns of antithrombotic therapy and association with clinical outcomes in patients with atrial fibrillation (AF) and CHA2DS2-VASc (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, prior stroke or transient ischemic attack or thromboembolism, vascular disease, age 65-74 years, sex category) score ≥2 following transcatheter aortic valve replacement (TAVR).

BACKGROUND

The impact of antithrombotic regimens on clinical outcomes in patients with AF and severe aortic stenosis treated with TAVR is unknown.

METHODS

In the randomized PARTNER II (Placement of Aortic Transcatheter Valve II) trial and associated registries, 1,621 patients with prior AF and CHA2DS2-VASc score ≥2 comprised the study cohort. Outcomes were analyzed according to antithrombotic therapy.

RESULTS

During the 5-year enrollment period, 933 (57.6%) patients were discharged on oral anticoagulant therapy (OAC). Uninterrupted antiplatelet therapy (APT) for at least 6 months or until an endpoint event was used in 544 of 933 (58.3%) of patients on OAC and 77.5% of patients not on OAC. At 2 years, patients on OAC had a similar rate of stroke (6.6% vs. 5.6%; p = 0.53) and the composite outcome of death or stroke (29.7% vs. 31.8%; p = 0.33), compared with no OAC. OAC with APT was associated with a reduced rate of stroke (5.4% vs. 11.1%; p = 0.03) and death or stroke (29.7% vs. 40.1%; p = 0.01), compared with no OAC or APT. Following adjustment, OAC with APT and APT alone were both associated with reduced rates of stroke compared with no OAC or APT (hazard ratio for OAC+APT: 0.43, 95% confidence interval: 0.22 to 0.85; p = 0.015; hazard ratio for APT alone: 0.32, 95% confidence interval: 0.16 to 0.65; p = 0.002), while OAC alone was not.

CONCLUSIONS

Among patients with prior AF undergoing TAVR, antiplatelet with or without anticoagulant therapy was associated with a reduced risk of stroke at 2 years, implicating multifactorial stroke mechanisms in this population.

Citrullinated histone H3, a biomarker for neutrophil extracellular trap formation, predicts the risk of mortality in patients with cancer

Prior studies indicate that neutrophil extracellular traps (NETs) are associated with arterial thromboembolism (ATE) and mortality. We investigated the association between NET formation biomarkers (citrullinated histone H3 [H3Cit], cell-free DNA [cfDNA], and nucleosomes) and the risk of ATE and all-cause mortality in patients with cancer. In this prospective cohort study, H3Cit, cfDNA and nucleosome levels were determined at study inclusion, and patients with newly diagnosed cancer or progressive disease after remission were followed for 2 years for ATE and death. Nine-hundred and fifty-seven patients were included. The subdistribution hazard ratios for ATE of H3Cit, cfDNA and nucleosomes were 1·0 per 100 ng/ml increase (95% confidence interval [95% CI]: 0·7-1·4, P = 0·949), 1·0 per 100 ng/ml (0·9-1·2, P = 0·494) increase and 1·1 per 1-unit increase (1·0-1·2, P = 0·233), respectively. Three-hundred and seventy-eight (39·5%) patients died. The hazard ratio (HR) for mortality of H3Cit and cfDNA per 100 ng/ml increase was 1·1 (1·0-1·1, P < 0·001) and 1·1 (1·0-1·1, P < 0·001), respectively. The HR for mortality of nucleosome levels per 1-unit increase was 1·0 (1·0-1·1, P = 0·233). H3Cit, cfDNA and nucleosome levels were not associated with the risk of ATE in patients with cancer. Elevated H3Cit and cfDNA levels were associated with higher mortality in patients with cancer.

A multidisciplinary consensus on dehydration: definitions, diagnostic methods and clinical implications

Background: Dehydration appears prevalent, costly and associated with adverse outcomes. We sought to generate consensus on such key issues and elucidate need for further scientific enquiry. Materials and methods: A modified Delphi process combined expert opinion and evidence appraisal. Twelve relevant experts addressed dehydration's definition, objective markers and impact on physiology and outcome. Results: Fifteen consensus statements and seven research recommendations were generated. Key findings, evidenced in detail, were that there is no universally accepted definition for dehydration; hydration assessment is complex and requires combining physiological and laboratory variables; "dehydration" and "hypovolaemia" are incorrectly used interchangeably; abnormal hydration status includes relative and/or absolute abnormalities in body water and serum/plasma osmolality (pOsm); raised pOsm usually indicates dehydration; direct measurement of pOsm is the gold standard for determining dehydration; pOsm >300 and ≤280 mOsm/kg classifies a person as hyper or hypo-osmolar; outside extremes, signs of adult dehydration are subtle and unreliable; dehydration is common in hospitals and care homes and associated with poorer outcomes. Discussion: Dehydration poses risk to public health. Dehydration is under-recognized and poorly managed in hospital and community-based care. Further research is required to improve assessment and management of dehydration and the authors have made recommendations to focus academic endeavours. Key messages Dehydration assessment is a major clinical challenge due to a complex, varying pathophysiology, non-specific clinical presentations and the lack of international consensus on definition and diagnosis. Plasma osmolality represents a valuable, objective surrogate marker of hypertonic dehydration which is underutilized in clinical practice. Dehydration is prevalent within the healthcare setting and in the community, and appears associated with increased morbidity and mortality.

Qualitative evaluation of coronary atherosclerosis in a large cohort of young and middle-aged Dutch tissue donors implies that coronary thrombo-embolic manifestations are stochastic

Background and aims

With the intention to gain support for the hypothesis that incident ischemic complications of atherosclerotic disease involve a stochastic aspect, we performed a histological, qualitative evaluation of the epidemiology of coronary atherosclerotic disease in a cohort of aortic valve donors.

Patients and methods

Donors (n = 695, median age 54, range 11–65 years) were dichotomized into a non-cardiovascular (non-CVD) and a cardiovascular disease death (CVD) group. Consecutive 5 mm proximal left coronary artery segments were Movat stained, and the atherosclerotic burden for each segment was graded (revised AHA-classification).

Results

Non-CVD and CVD groups showed steep increase of atherosclerosis severity beyond the age of 40, resulting in an endemic presence of advanced atherosclerosis in men over 40 and women over 50 years. In fact, only 19% of the non-CVD and 6% of the CVD donors over 40 years were classified with a normal LCA or a so called non-progressive lesion type. Fibrous calcified plaques (FCP), the consolidated remnants of earlier ruptured lesions, dominated in both non-CVD and CVD donors. Estimates of the atherosclerosis burden (i.e. average lesion grade, proportion of FCPs, and average number of FCPs per cross-section) were all higher in the CVD group (p<1.10⁻¹⁶, p<0.0001, and p<0.05, respectively).

Conclusions

Dominance of consolidated FCP lesions in males over 40 and females over 50 years, show that plaque ruptures in the left coronary artery are common. However, the majority of these ruptures remain asymptomatic. This implies that the atherosclerotic process is repetitive. A relative difference in disease burden between CVD and non-CVD donors supports the concept that complications of atherosclerotic disease involve a stochastic element.

Thromboembolism and Mortality in the Tasmanian Atrial Fibrillation Study

BACKGROUND

Although utilization of anticoagulation in patients with atrial fibrillation (AF) has increased in recent years, contemporary data regarding thromboembolism and mortality incidence rates are limited outside of clinical trials. This study aimed to investigate the impact of the direct oral anticoagulants (DOACs) on the clinical outcomes of patients with AF included in the Tasmanian Atrial Fibrillation Study.

METHODS

The medical records of all patients with a primary or secondary diagnosis of AF who presented to public hospitals in Tasmania, Australia, between 2011 and 2015, were retrospectively reviewed. We investigated overall thromboembolic events (TEs), ischemic stroke/transient ischemic attack (IS/TIA), and mortality incidence rates in patients admitted to the Royal Hobart Hospital, the main teaching hospital in the state. We compared outcomes in 2 time periods: prior to the availability of DOACs (pre-DOAC; 2011 to mid-2013) and following their general availability after government subsidization (post-DOAC; mid-2013 to 2015).

RESULTS

Of the 2390 patients with AF admitted during the overall study period, 942 patients newly prescribed an antithrombotic medication (465 and 477 from the pre-DOAC and post-DOAC time periods, respectively) were followed. We observed a significant decrease in the incidence rates of overall TE (3.2 vs 1.7 per 100 patient-years [PY]; P < .001) and IS/TIA (2.1 vs 1.3 per 100 PY; P = .022) in the post-DOAC compared to the pre-DOAC period. All-cause mortality was significantly lower in the post-DOAC period (2.9 vs 2.2 per 100 PY, P = .028). Increasing age, prior stroke, and admission in the pre-DOAC era were all risk factors for TE, IS/TIA, and mortality in this study population. The risk of IS/TIA was more than doubled (hazard ratio: 2.54; 95% confidence interval: 1.17-5.52) in current smokers compared to ex- and nonsmokers.

CONCLUSION

Thromboembolic event and all-cause mortality rates were lower following the widespread availability of DOACs in this population.

CHA2DS2-VASc score as a predictor of long-term cardiac outcomes in elderly patients with or without atrial fibrillation

BACKGROUND

The CHA2DS2-VASc score is often used for stroke risk stratification in atrial fibrillation (AF) patients. However, its usefulness in patients ≥75 years of age with or without AF is unclear.

OBJECTIVE

We aimed to investigate whether the CHA2DS2-VASc score can predict ischemic stroke (IS), transient ischemic attack, thromboembolism (TE), and mortality in elderly patients with and without AF.

MATERIALS AND METHODS

During 2013-2014, 1,071 patients (36.3% with concomitant AF) at least 75 years old were enrolled, and the follow-up ended on July 15, 2017. Variables included sociodemographic characteristics, complications, drugs taken, laboratory results, and echocardiographic parameters. The primary end points were IS, transient ischemic attack, and TE, expressed as IS/TE. All-cause mortality was a secondary end point. Survival curves and mortality risks were assessed via Kaplan-Meier survival analysis and compared by log-rank tests.

RESULTS

The average follow-up duration was 2.57±1.37 years. Overall, 167 patients (5.6%) died and 77 (7.2%) developed IS/TE. The CHA2DS2-VASc score was associated with IS/TE in patients 75 years or older with and without AF, and patients with a CHA2DS2-VASc score ≥5 had a higher risk of stroke. However, the CHA2DS2-VASc score was not related to all-cause mortality.

CONCLUSION

The CHA2DS2-VASc score can predict IS/TE, but not mortality, in elderly patients (≥75 years) with or without AF.

Dyslipidemia and Risk of Cardiovascular Events in Patients With Atrial Fibrillation Treated With Oral Anticoagulation Therapy: Insights From the ARISTOTLE (Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation) Trial

BACKGROUND

Dyslipidemia is a major risk factor for cardiovascular events. The prognostic importance of lipoproteins in patients with atrial fibrillation is not well understood. We aimed to explore the association between apolipoprotein A1 (ApoA1) and B (ApoB) and cardiovascular events in patients with atrial fibrillation receiving oral anticoagulation.

METHODS AND RESULTS

Using data from the ARISTOTLE (Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation) trial, ApoA1 and ApoB plasma levels were measured at baseline in 14 884 atrial fibrillation patients. Median length of follow-up was 1.9 years. Relationships between continuous levels of ApoA1 and ApoB and clinical outcomes were evaluated using Cox models adjusted for cardiovascular risk factors, medication including statins, and cardiovascular biomarkers. A composite ischemic outcome (ischemic stroke, systemic embolism, myocardial infarction, and cardiovascular death) was used as the primary end point. Median (25th, 75th) ApoA1 and ApoB levels were 1.10 (0.93, 1.30) and 0.70 g/L (0.55, 0.85), respectively. In adjusted analyses, higher levels of ApoA1 were independently associated with a lower risk of the composite ischemic outcome (hazard ratio, 0.81; P<0.0001). Similar results were observed for the individual components of the composite outcome. ApoB was not significantly associated with the composite ischemic outcome (P=0.8240). Neither apolipoprotein was significantly associated with major bleeding. There was no interaction between lipoproteins and randomized treatment for the primary outcome (both P values ≥0.2448).

CONCLUSIONS

In patients with atrial fibrillation on oral anticoagulation, higher levels of ApoA1 were independently associated with lower risk of ischemic cardiovascular outcomes. Investigating therapies targeting dyslipidemia may thus be useful to improve cardiovascular outcomes in patients with atrial fibrillation.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00412984.

Role of rivaroxaban in the management of atrial fibrillation: insights from clinical practice

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, and it leads to significant morbidity and mortality, predominantly from ischemic stroke. Vitamin K antagonists, mainly warfarin, have been used for decades to prevent ischemic stroke in AF, but their use is limited due to interactions with food and other drugs, as well as the requirement for regular monitoring of the international normalized ratio. Rivaroxaban, a direct factor Xa inhibitor and the most commonly used non-vitamin K oral anticoagulant, avoids many of these challenges and is being prescribed with increasing frequency for stroke prevention in non-valvular AF. Randomized controlled trial (RCT) data from the ROCKET-AF(Rivaroxaban once daily oral direct Factor Xa inhibition compared with vitamin K antagonism for prevention of stroke and embolism trial in atrial fibrillation) trial have shown rivaroxaban to be non-inferior to warfarin in preventing ischemic stroke and systemic embolism and to have comparable overall bleeding rates. Applicability of the RCT data to real-world practice can sometimes be limited by complex clinical scenarios or multiple comorbidities not adequately represented in the trials. Available real-world evidence in non-valvular AF patients with comorbidities - including renal impairment, acute coronary syndrome, diabetes mellitus, malignancy, or old age - supports the use of rivaroxaban as safe and effective in preventing ischemic stroke in these subgroups, though with some important considerations required to reduce bleeding risk. Patient perspectives on rivaroxaban use are also considered. Real-world evidence indicates superior rates of drug adherence with rivaroxaban when compared with vitamin K antagonists and with alternative non-vitamin K oral anticoagulants - perhaps, in part, due to its once-daily dosing regimen. Furthermore, self-reported quality of life scores are highest among patients compliant with rivaroxaban therapy. The generally high levels of patient satisfaction with rivaroxaban therapy contribute to overall favorable clinical outcomes.

Effectiveness and safety of oral anticoagulants in older patients with atrial fibrillation: a systematic review and meta-regression analysis

Background and objective

the study analysed the effectiveness and safety of warfarin use compared with warfarin non-use and non-vitamin K antagonist oral anticoagulants (NOACs) in atrial fibrillation (AF) patients aged ≥65 years.

Methods

after searching PubMed and the Cochrane Library, 26 studies were included, with 10 comparing warfarin with warfarin non-use and 16 comparing warfarin with NOACs, in older AF patients (≥65 years).

Results

warfarin use was superior to no antithrombotic therapy [relative risk (RR) 0.59, 95% confidence interval (CI) 0.51-0.76, I2 = 12.3%, n = 8] and aspirin (RR 0.44, 95% CI 0.24-0.64, I2 = 0.0%, n = 5) for stroke/thromboembolism (TE) prevention. Warfarin use was associated with a non-significant increase in risk of major bleeding compared with no antithrombotic therapy (RR 1.26, 95% CI 0.99-1.52, I2 = 0.0%, n = 7) and aspirin (RR 1.20, 95% CI 0.91-1.50, I2 = 0.0%, n = 5). NOACs were superior to warfarin for stroke/TE prevention [hazard ratio (HR) 0.81, 95% CI 0.73-0.89, I2 = 56.6%, n = 9], and also were associated with reduced risk of major bleeding compared to warfarin (HR 0.87, 0.77-0.97, I2 = 86.1%, n = 9).

Conclusions

warfarin use was superior to warfarin non-use, aspirin and no antithrombotic therapy in reducing the risk of stroke/TE in older AF patients, but with a possible increase in major bleeding. NOACs were superior to warfarin for stroke/TE prevention, with reduced risk of major bleeding.

Nitroaspirin plus clopidogrel versus aspirin plus clopidogrel against platelet thromboembolism and intimal thickening in mice

Clopidogrel plus aspirin is the treatment of choice for patients undergoing percutaneous, coronary interventions with stenting, but it does not prevent restenosis. NCX-4016, a nitric oxide-releasing aspirin (nitroaspirin), exerts a wider range of antiplatelet actions compared to aspirin, superior antithrombotic activity and reduces restenosis after arterial injury in animals. The aim of the present study was to compare the combination of nitroaspirin plus clopidogrel with aspirin plus clopidogrel in a model of platelet pulmonary thromboembolism, bleeding and intimal thickening in mice. Drugs were administered orally for 5 days; the antithrombotic effects were evaluated against collagen plus epinephrine-induced pulmonary thromboembolism, the haemorrhagic effects by tail transection bleeding time and the effects on neointima proliferation by histomorphology of photochemically injured femoral arteries. Lung platelet emboli were reduced significantly and more effectively by nitroaspirin plus clopidogrel (-56%, p< 0.05 vs control) than by aspirin plus clopidogrel (-26%, p< 0.05 vs control). Ex vivo platelet aggregation was inhibited maximally by nitroaspirin plus clopidogrel. Aspirin plus clopidogrel strikingly prolonged the bleeding time while nitroaspirin plus clopidogrel induced a lesser prolongation. Nitroaspirin plus clopidogrel significantly reduced intimal thickening of the femoral artery while aspirin plus clopidogrel was ineffective. Nitroaspirin plus clopidogrel is more effective and less prohaemorrhagic than aspirin plus clopidogrel in mice; provided these data are confirmed in other animal models, nitroaspirin plus clopidogrel may represent a new regimen to be tested in patients undergoing coronary revascularization procedures.

Age- and sex-specific incidence, risk, and latency period of a perioperative acute thromboembolism syndrome (PATS)

We investigated age- and sex-specific incidence, risk factors, and latency period of a perioperative acute thromboembolism syndrome (PATS) in a large cohort study. We prospectively analyzed data on 21903 consecutive surgery patients to determine the incidence of myocardial infarction, pulmonary embolism, deep venous thrombosis, stroke, and cardiovascular death within 30 postoperative days. Among 255 (1.2 percent) patients with thromboembolism, 105 (0.48 percent) suffered myocardial infarction (mean latency: 5 days), 30 (0.14 percent) suffered pulmonary embolism (6 days), 23 (0.11 percent) suffered deep venous thrombosis (10 days), 97 (0.44 percent) suffered stroke (11 days), and 13 (0.06 percent) died (12 days). The critical period was postoperative week 1 for myocardial infarction and pulmonary embolism, and postoperative week 1 and 2 for deep venous thrombosis, stroke, and death. Risk of all events increased with age (P<0.0001), particularly for over 70 years (odds ratio: 12.5; 95 percent confidence interval, 7.8 to 19.9). Males had an increased risk (P<0.0001) of myocardial infarction (odds ratio; 1.5; 95 percent confidence interval, 1.0 to 2.3). Females had an increased risk (P<0.0001) of pulmonary embolism (odds ratio: 2.7; 95 percent confidence interval, 1.3 to 5.9) and deep venous thrombosis (odds ratio: 9.8; 95 percent confidence interval, 3.3 to 29.3). Risk of thromboembolic event was higher (P<0.0001) in patients with a history of arterial thrombotic events or cancer. Trend analysis indicates that thromboembolic events will increase 3-fold over the next decade. Our findings enable identification of higher risk patients for prophylactic anti-thromboembolic treatment and awareness of the critical postoperative period.

Caplacizumab reduces the frequency of major thromboembolic events, exacerbations and death in patients with acquired thrombotic thrombocytopenic purpura

Essentials Acquired thrombotic thrombocytopenic purpura (aTTP) is linked with significant morbidity/mortality. Caplacizumab's effect on major thromboembolic (TE) events, exacerbations and death was studied. Fewer caplacizumab-treated patients had a major TE event, an exacerbation, or died versus placebo. Caplacizumab has the potential to reduce the acute morbidity and mortality associated with aTTP.

SUMMARY

Background Acquired thrombotic thrombocytopenic purpura (aTTP) is a life-threatening autoimmune thrombotic microangiopathy. In spite of treatment with plasma exchange and immunosuppression, patients remain at risk for thrombotic complications, exacerbations, and death. In the phase II TITAN study, treatment with caplacizumab, an anti-von Willebrand factor Nanobody® was shown to reduce the time to confirmed platelet count normalization and exacerbations during treatment. Objective The clinical benefit of caplacizumab was further investigated in a post hoc analysis of the incidence of major thromboembolic events and exacerbations during the study drug treatment period and thrombotic thrombocytopenic purpura-related death during the study. Methods The Standardized Medical Dictionary for Regulatory Activities (MedDRA) Query (SMQ) for 'embolic and thrombotic events' was run to investigate the occurrence of major thromboembolic events and exacerbations in the safety population of the TITAN study, which consisted of 72 patients, of whom 35 received caplacizumab and 37 received placebo. Results Four events (one pulmonary embolism and three aTTP exacerbations) were reported in four patients in the caplacizumab group, and 20 such events were reported in 14 patients in the placebo group (two acute myocardial infarctions, one ischemic stroke, one hemorrhagic stroke, one pulmonary embolism, one deep vein thrombosis, one venous thrombosis, and 13 aTTP exacerbations). Two of the placebo-treated patients died from aTTP during the study. Conclusion In total, 11.4% of caplacizumab-treated patients and 43.2% of placebo-treated patients experienced one or more major thromboembolic events, experienced an exacerbation, or died. This analysis shows the potential for caplacizumab to reduce the risk of major thromboembolic morbidities and mortality associated with aTTP.

Novel Oral Anticoagulants in Patients Undergoing Cranial Surgery

BACKGROUND

The number of patients treated with novel oral anticoagulants (NOACs) is increasing. Despite growing clinical relevance, guidelines on the perioperative management of neurosurgical patients treated with NOACs are still lacking. The aim of this study was to analyze the occurrence of postoperative bleeding events and factors that might influence bleeding rates in these patients.

METHODS

Out of 1353 consecutive patients undergoing cranial neurosurgical procedures, 30 (2.2%) received NOACs preoperatively. The rates of perioperative and postoperative intracranial bleeding events, rate of postoperative thromboembolic events, hematologic findings, morbidity, and mortality were reviewed. A subanalysis of factors influencing the bleeding risk of these patients and the bleeding rate depending on the preoperative discontinuation time of NOACS, with cutoff of 24 and 48 hours, was performed as well.

RESULTS

The rate of perioperative bleeding was 13.3% (n = 4 of 30). Postoperative bleeding led to death in 2 patients. The median discontinuation time was significantly shorter in the patients experiencing a bleeding event compared to those without a bleeding event (1.5 days [range 0-3 days] vs. 11 days [range, 0-120 days]). The rate of perioperative thromboembolic events was 3.3% (n = 1), and overall mortality was 13.3% (n = 4).

CONCLUSIONS

The postoperative bleeding rate in patients undergoing cranial surgery treated with NOACs was 13.3%. A shorter preoperative discontinuation time seems to have a significant effect on bleeding rate. Further studies evaluating the management and postsurgical outcomes of these patients are warranted.

Self-reported physical activity and major adverse events in patients with atrial fibrillation: a report from the EURObservational Research Programme Pilot Survey on Atrial Fibrillation (EORP-AF) General Registry

AIMS

Physical activity is protective against cardiovascular (CV) events, both in general population and in high-risk CV cohorts. However, the relationship between physical activity with major adverse outcomes in atrial fibrillation (AF) is not well-established. Our aim was to analyse this relationship in a 'real-world' AF population. Second, we investigated the influence of physical activity on arrhythmia progression.

METHODS AND RESULTS

We studied all patients enrolled in the EURObservational Research Programme on AF (EORP-AF) Pilot Survey. Physical activity was defined as 'none', 'occasional', 'regular', and 'intense', based on patient self-reporting. Data on physical activity were available for 2442 patients: 38.9% reported none, 34.7% occasional, 21.7% regular, and 4.7% intense physical activity. Prevalence of the principal CV risk factors progressively decreased from none to intense physical activity. Lower rates of CV death, all-cause death, and composite outcomes were found in AF patients who reported regular and intense physical activity (P < 0.0001). Increasing physical activity was inversely associated with CV death/any thromboembolic event (TE)/bleeding in the whole cohort, irrespective of gender, paroxysmal AF, elderly age, or high stroke risk. Any level of physical activity intensity was significantly associated with lower risk of CV death/any TE/bleeding at 1-year follow-up. Physical activity was not significantly associated with arrhythmia progression.

CONCLUSION

Atrial fibrillation patients taking regular exercise were associated with a lower risk of all-cause death, even when we considered various subgroups, including gender, elderly age, symptomatic status, and stroke risk class. Efforts to increase physical activity among AF patients may improve outcomes in these patients.

CHA2DS2-VASc Score: A Predictor of Thromboembolic Events and Mortality in Patients With an Implantable Monitoring Device Without Atrial Fibrillation

OBJECTIVE

To determine if the CHA₂DS₂-VASc score (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, stroke or transient ischemic attack, vascular disease, age 65-74 years, sex category) predicts thromboembolism and death in patients without atrial fibrillation in a population with implantable cardiac monitoring devices.

PATIENTS AND METHODS

A retrospective review utilizing the Rochester Epidemiology Project research infrastructure was conducted to evaluate the CHA₂DS₂-VASc tool as a predictor of mortality and ischemic stroke, transient ischemic attack, or systemic embolism in patients without atrial fibrillation. An implantable device was required in the inclusion criteria to discern the absence of atrial fibrillation. The study period was January 1, 2004, through March 7, 2016.

RESULTS

The study population (N=1606) had a mean (SD) age of 69.8 (12.6) years and median follow-up of 4.8 years (range, 0-12 years; quartile 1, 2.6 years and quartile 3, 8.1 years). The number of thromboembolic and mortality events stratified by CHA₂DS₂-VASc score groupings of 0 to 2 (399 patients), 3 to 5 (756 patients), and 6 to 9 (451 patients) were 12 (3.0%), 109 (14.4%), and 123 (27.3%) and 22 (5.5%), 205 (27.1%), and 214 (47.4%), respectively. The CHA₂DS₂-VASc score predicted thromboembolism and death. The hazard ratios (HRs) for thromboembolic events for CHA₂DS₂-VASc scores 3 to 5 and 6 to 9 were 4.84 (95% CI, 2.66-8.80) and 10.53 (95% CI, 5.77-19.21) (reference group, scores 0-2). The HRs for death for the corresponding score categories were 4.45 (95% CI, 2.86-6.91) and 8.18 (95% CI, 5.23-12.78). The CHA₂DS₂-VASc score also predicted development of atrial fibrillation, for which the HRs for scores 3 to 5 and 6 to 9 were 1.51 (95% CI, 1.13-2.00) and 2.17 (95% CI, 1.60-2.95).

CONCLUSION

The CHA₂DS₂-VASc tool predicts thromboembolic events and overall mortality in patients without atrial fibrillation who have implantable devices.

Low-Dose Warfarin for Prevention of Symptomatic Thromboembolism after Orthopedic Surgery

BACKGROUND:

Warfarin dosing with a target international normalized ratio (INR) range of 1.5–2.5 has not been reported as adequate for venous thromboembolism (VTE) prophylaxis after total knee (TKR) and total hip replacement (THR) surgery. OBJECTIVE: To evaluate the rate of symptomatic VTE after TKR and THR surgery using a low-dose (INR 1.5–2.5) warfarin protocol started the evening before surgery compared with a literature cohort treated with enoxaparin.

METHODS:

TKR/THR patients treated with a 21-day low-dose warfarin protocol were followed via a consecutive observational design. Main outcome measures were symptomatic VTE and pulmonary embolism (PE), with major bleeds and death as secondary outcomes. Low-dose warfarin was compared with a literature cohort of patients treated with enoxaparin who received enoxaparin for a similar length of time and was evaluated for the same outcomes. Cohort event rates were derived as a weighted average using the DerSimonian model.

RESULTS:

VTE, PE, bleeds, and deaths in the low-dose warfarin group were 8 (1.04%), 4 (0.52%), 8 (1.04%), and 4 (0.52%), respectively. The cohort weighted average values were 35 (1.33%), 19 (0.72%), 65 (2.46%), and 18 (0.67%), respectively. Odds ratios for low-dose warfarin for VTE, PE, and VTE plus PE were 0.778 (95% CI 0.36 to 1.68), 0.717 (0.24 to 2.11), and 0.754 (0.41 to 1.42), respectively, all nonsignificant. Odds ratios for bleeds and death were 0.420 (0.20 to 0.87; p = 0.02) and 0.756 (0.26 to 2.24; NS), respectively.

CONCLUSIONS:

For this evaluation, low-dose warfarin was comparable to the enoxaparin cohort for development of VTE, PE, and VTE+PE. Incidences of bleeds in the enoxaparin cohort were significantly higher than in patients receiving low-dose warfarin.

Factors Associated with Pulmonary Embolism Recurrence and the Benefits of Long-term Anticoagulant Therapy

BACKGROUND

Venous thromboemboli tend to recur. However, the causative factors underlying pulmonary embolism recurrence are not well defined.

AIMS

To explore the factors associated with pulmonary embolism recurrence.

PATIENTS AND METHODS

Patients diagnosed with pulmonary emboli between 2004 and 2013 at our institution were enrolled. Duration of anticoagulant therapy, new episodes of venous thromboembolism, and deaths were recorded.

RESULTS

Pulmonary embolism was diagnosed in 528 patients (median age: 76 years, interquartile range [IQR]: 16; male: 45%). The median follow-up time was 34 months (IQR: 52). In total, 477 patients completed ≥3 months of anticoagulation therapy. Permanent anticoagulation was indicated in 217 (45%) patients, and therapy was discontinued in 260 (55%) patients. Overall, 79 patients experienced a recurrence (5.6 per patient-year). Recurrence was significantly associated with anticoagulation discontinuation (4% vs. 27% of patients who maintained or discontinued therapy, respectively; P<0.001; 95% confidence interval -0.95, -0.86). The median duration between anticoagulation withdrawal and recurrence was 6.5 months (IQR: 23.25). Factors associated with recurrence were unprovoked pulmonary embolism (odds ratio [OR]: 0.45), a greater degree of pulmonary arterial obstruction (OR: 2.5), a delay in initiation of anticoagulation (OR: 3), and higher plasma D-dimer levels during treatment (OR: 2.3). Survival rates were improved for patients who maintained anticoagulation therapy relative to those who discontinued.

CONCLUSION

Pulmonary embolism has a high recurrence rate. Permanent anticoagulant therapy should be considered for patients with idiopathic pulmonary embolism, a high thrombotic burden, and persistently elevated D-dimer levels during treatment, and for patients where therapy was initially delayed.

What to do after the bleed: resuming anticoagulation after major bleeding

Resuming anticoagulation therapy after a potentially life-threatening bleeding complication evokes high anxiety levels among clinicians and patients trying to decide whether resuming oral anticoagulation to prevent devastating and potentially fatal thromboembolic events or discontinuing anticoagulation in hopes of reducing the risk of recurrent bleeding is best. The available evidence favors resumption of anticoagulation therapy for gastrointestinal tract bleeding and intracranial hemorrhage survivors, and it is reasonable to begin postbleeding decision making with resuming anticoagulation therapy as the default plan. After considering factors related to the index bleeding event, the underlying thromboembolic risk, and comorbid conditions, a decision to accept or modify the default plan can be made in collaboration with other care team members, the patient, and their caregivers. Although additional information is needed regarding the optimal timing of anticoagulation resumption, available evidence indicates that waiting ∼14 days may best balance the risk of recurrent bleeding, thromboembolism, and mortality after gastrointestinal tract bleeding. When to resume anticoagulation after intracranial hemorrhage is less clear, but most studies indicate that resumption within the first month of discharge is associated with better outcomes.

Reasons for and consequences of vitamin K antagonist discontinuation in very elderly patients with non-valvular atrial fibrillation

Essentials Anticoagulation in the elderly is still a challenge and suspension of warfarin is common. This is an observational study reporting reasons and consequences of warfarin suspension. Vascular disease, age, time in therapeutic range, and bleedings are associated with suspension. After suspension for bleeding or frailty, patients remain at high-risk of death or complications.

SUMMARY

Background Anticoagulation in elderly patients with non-valvular atrial fibrillation (NVAF) is still a challenge, and discontinuation of warfarin is common. The aim of this study was to analyze the aspects related to warfarin discontinuation in a real-world population. Methods This was an observational cohort study on very elderly NVAF patients naive to warfarin therapy (VENPAF). The included subjects were aged at least 80 years, and started using warfarin after a diagnosis of NVAF. Warfarin discontinuation was assessed, and the reason reported for discontinuation, the person who decided to stop treatment, subsequent antithrombotic therapy and mortality, ischemic and bleeding events were collected. Results Over a period of 5 years, warfarin was discontinued in 148 of 798 patients. Despite similar CHA2 DS2 -VASc scores, the frequencies of thromboembolic and major bleeding events were significantly higher (P = 0.01 and P = 0.001, respectively) and the time in therapeutic range (TTR) was significantly lower (P < 0.001) in patients who discontinued warfarin. Independent risk factors for warfarin discontinuation were vascular disease (hazard ratio [HR] 2.5, P < 0.001), age ≥ 85 years (HR 1.4, P = 0.04), TTR < 60% (HR 1.8, P = 0.001), and bleeding events (HR 2.3, P < 0.001). The main reasons for warfarin discontinuation were physician-perceived frailty or low life-expectancy (45.9%), bleeding complications (19.6%), and sinus rhythm restoration (16.9%). Event and death rates were very high, especially in frail patients and in those with bleeding complications. Conclusions Warfarin discontinuation is frequent in very elderly patients, and is associated with increased risks of death and adverse events. Identification of elderly patients who are at high risk of bleeding and the poor quality of anticoagulation during warfarin are still unsolved clinical problems.

Long-Term Outcome of Non-Sustained Ventricular Tachycardia in Structurally Normal Hearts

Background

The impact of non-sustained ventricular tachycardia (NSVT) on the risk of thromboembolic event and clinical outcomes in patients without structural heart disease remains undetermined. This study aimed to evaluate the association between NSVT and clinical outcomes.

Methods

The study population of 5903 patients was culled from the “Registry of 24-hour ECG monitoring at Taipei Veterans General Hospital” (REMOTE database) between January 1, 2002 and December 31, 2004. Of that total, we enrolled 3767 patients without sustained ventricular tachycardia, structural heart disease, and permanent pacemaker. For purposes of this study, NSVT was defined as 3 or more consecutive beats arising below the atrioventricular node with an RR interval of <600 ms (>100 beats/min) and lasting < 30 seconds.

Result

There were 776 deaths, 2042 hospitalizations for any reason, 638 cardiovascular (CV)-related hospitalizations, 350 ischemic strokes, 409 transient ischemic accident (TIA), 368 new-onset heart failure (HF), and 260 new-onset atrial fibrillation (AF) with a mean follow-up duration of 10 ± 1 years. In multivariate analysis, the presence of NSVT was independently associated with death (hazard ratio [HR]: 1.362, 95% confidence interval [CI]: 1.071–1.731), CV hospitalization (HR: 1.527, 95% CI: 1.171–1.992), ischemic stroke (HR: 1.436, 95% CI: 1.014–2.032), TIA (HR 1.483, 95% CI: 1.069–2.057), and new-onset HF (HR: 1.716, 95% CI: 1.243–2.368). There was no significant association between the presence of NSVT and all-cause hospitalization or new-onset AF.

Conclusion

In patients without structural heart disease, presence of NSVT on 24-hour monitoring was independently associated with death, CV hospitalization, ischemic stroke, TIA, and new onset heart failure.

Patent foramen ovale in idiopathic pulmonary arterial hypertension: Long-term risk and morbidity

INTRODUCTION

Little is known about the presence of patent foramen ovale in idiopathic pulmonary arterial hypertension. While there is suspected worsening of hypoxemia confounding assessment and management of pulmonary hypertension, as well as possible increased morbidity from paradoxical emboli, there may be theoretical relief of worsening right-sided pressures by the same mechanism of right-to-left shunting.

METHODS

Retrospective review of consecutive patients diagnosed with idiopathic pulmonary arterial hypertension (WHO Group 1) via right heart catheterization, from 1998 to 2010. All patients also underwent a four chamber transthoracic echocardiogram with agitated saline contrast for the evaluation of patent foramen ovale. Primary clinical data was collected and compared between patients with and without patent foramen ovale along with univariable and multivariable predictors of long term survival.

RESULTS

One hundred and fifty five patients were included in the study, 42 with patent foramen ovale (27%). Patients with patent foramen ovale were younger at pulmonary arterial hypertension diagnosis and trended towards higher right ventricular systolic pressures on echocardiography and mean pulmonary arterial pressures by right heart catheterization. Predictors of mortality included age, diffusing capacity for carbon monoxide, and severe hypoxemia. Only diffusing capacity and age were predictive of mortality after adjustment for a priori covariables.

CONCLUSION

Patent foramen ovale is seen in a quarter of patients with idiopathic pulmonary arterial hypertension and associated with increased prevalence of severe hypoxemia but had no effect on long term survival.

Self-monitoring and self-management of oral anticoagulation

BACKGROUND

The introduction of point-of-care devices for the management of patients on oral anticoagulation allows self-testing by the patient at home. Patients who self-test can either adjust their medication according to a pre-determined dose-INR (international normalized ratio) schedule (self-management), or they can call a clinic to be told the appropriate dose adjustment (self-monitoring). Increasing evidence suggests self-testing of oral anticoagulant therapy is equal to or better than standard monitoring. This is an updated version of the original review published in 2010.

OBJECTIVES

To evaluate the effects on thrombotic events, major haemorrhages, and all-cause mortality of self-monitoring or self-management of oral anticoagulant therapy compared to standard monitoring.

SEARCH METHODS

For this review update, we re-ran the searches of the Cochrane Central Register of Controlled Trials (CENTRAL), 2015, Issue 6, the Cochrane Library, MEDLINE (Ovid, 1946 to June week 4 2015), Embase (Ovid, 1980 to 2015 week 27) on 1 July 2015. We checked bibliographies and contacted manufacturers and authors of relevant studies. We did not apply any language restrictions .

SELECTION CRITERIA

Outcomes analysed were thromboembolic events, mortality, major haemorrhage, minor haemorrhage, tests in therapeutic range, frequency of testing, and feasibility of self-monitoring and self-management.

DATA COLLECTION AND ANALYSIS

Review authors independently extracted data and we used a fixed-effect model with the Mantzel-Haenzel method to calculate the pooled risk ratio (RR) and Peto's method to verify the results for uncommon outcomes. We examined heterogeneity amongst studies with the Chi(2) and I(2) statistics and used GRADE methodology to assess the quality of evidence.

MAIN RESULTS

We identified 28 randomised trials including 8950 participants (newly incorporated in this update: 10 trials including 4227 participants). The overall quality of the evidence was generally low to moderate. Pooled estimates showed a reduction in thromboembolic events (RR 0.58, 95% CI 0.45 to 0.75; participants = 7594; studies = 18; moderate quality of evidence). Both, trials of self-management or self-monitoring showed reductions in thromboembolic events (RR 0.47, 95% CI 0.31 to 0.70; participants = 3497; studies = 11) and (RR 0.69, 95% CI 0.49 to 0.97; participants = 4097; studies = 7), respectively; the quality of evidence for both interventions was moderate. No reduction in all-cause mortality was found (RR 0.85, 95% CI 0.71 to 1.01; participants = 6358; studies = 11; moderate quality of evidence). While self-management caused a reduction in all-cause mortality (RR 0.55, 95% CI 0.36 to 0.84; participants = 3058; studies = 8); self-monitoring did not (RR 0.94, 95% CI 0.78 to 1.15; participants = 3300; studies = 3); the quality of evidence for both interventions was moderate. In 20 trials (8018 participants) self-monitoring or self-management did not reduce major haemorrhage (RR 0.95, 95% CI, 0.80 to 1.12; moderate quality of evidence). There was no significant difference found for minor haemorrhage (RR 0.97, 95% CI 0.67 to 1.41; participants = 5365; studies = 13). The quality of evidence was graded as low because of serious risk of bias and substantial heterogeneity (I(2) = 82%).

AUTHORS' CONCLUSIONS

Participants who self-monitor or self-manage can improve the quality of their oral anticoagulation therapy. Thromboembolic events were reduced, for both those self-monitoring or self-managing oral anticoagulation therapy. A reduction in all-cause mortality was observed in trials of self-management but not in self-monitoring, with no effects on major haemorrhage.

Low-Dose Anticoagulation in Chinese Patients with Mechanical Heart Valves

The aim of this study was to provide guidelines for optimal anticoagulation in Chinese patients after mechanical heart valve replacement. A Carbomedics valve was implanted in 178 patients between July 2000 and July 2003. During follow-up, 22 bleeding events and 1 thromboembolic complication occurred. The linearized rates of bleeding and thromboembolism were 5.83% and 0.26% per patient-year, respectively. The linearized mortality rate was 0.79% per patient-year. The final mean international normalized ratio (INR) was 1.68 ± 0.38, however there was a significant variation between the early and late periods of follow-up. For Chinese patients with mechanical heart valves, bleeding was the major complication rather than thromboembolism. Low-dose anticoagulation (international normalized ratio 1.4–2.0) could markedly decrease bleeding and effectively prevent thromboembolism. As the INR was most unstable in the first postoperative month, re-examination of patients in this period is critical.

Prospective study of thromboembolism in 1038 children with acute lymphoblastic leukemia: a Nordic Society of Pediatric Hematology and Oncology (NOPHO) study

ESSENTIALS: Children with acute lymphoblastic leukemia (ALL) are at risk of thromboembolism (TE). This is a prospective evaluation of the incidence, risk factors and outcomes of TE in 1038 children with ALL. TE occurred in 6.1% of children, with the highest incidence (20.5%) among those aged 15-17 years. A TE-associated case fatality of 6.4% indicates that TE is a severe complication of ALL treatment.

SUMMARY

BACKGROUND

Thromboembolism (TE) is a major toxicity in children with acute lymphoblastic leukemia (ALL) and may have a negative impact on ALL treatment.

OBJECTIVES

To examine the cumulative incidence, outcomes and risk factors associated with TE in children with leukemia.

PATIENTS/METHODS

We prospectively evaluated TE in 1038 Nordic children and adolescents (≥ 1 and < 18 years) diagnosed with ALL during 2008-2013 and treated according to the NOPHO (Nordic Society of Pediatric Hematology and Oncology)-ALL 2008 protocol. The cohort was followed until December 2014. Cox proportional regression was used to compute hazard ratios (HRs).

RESULTS

TE events (n = 63) occurred most frequently in conjunction with asparaginase (ASP) administration (52/63). The cumulative incidence of TE was 6.1% (95% confidence interval [CI], 4.8-7.7). Being aged 15-17 years was associated with an increased risk of TE (adjusted HR of 4.0; 95% CI, 2.1-7.7). We found a TE-associated 30-day case fatality of 6.4% (95% CI, 1.8-15.5) and TE-related truncation of ASP therapy in 36.2% (21/58). Major hemorrhage occurred in 3.5% (2/58) of anticoagulated patients. Minor hemorrhage was reported in two out of 58 patients. No major bleeds occurred in children who received low-molecular-weight heparin.

CONCLUSIONS

Methods to identify children and adolescents who will benefit from thromboprophylaxis during ALL treatment are called for. The truncation of ASP should be avoided. The long-term survival outcomes for ALL patients with TE require close monitoring in the future.

[Low Intensity Anticoagulation Therapy for Chinese Population with Heart Valve Replacement--3 000 Cases Follow-up]

OBJECTIVE

To investigate the effect of low-intensity anticoagulation therapy for Chinese population with heart valve replacement.

METHODS

From January 2011 to March 2012, 3 000 patients with heart valve replacement in Fuwai Hospital and West China Hospital were followed-up for 1 year, the method and intensity of postoperative anticoagulation, as well as the complications were studied and analyzed.

RESULTS

The rate of follow-up was 88.57%, and the cumulative follow-up was 1 726.1 patient-years (Pty). The mean oral warfarin dosage was (2.68 ± 6.45) mg/d, and the mean INR values of the patients treated in Fuwai Hospital and West China Hospital were 2.01 ± 1.10 and 186 ± 0.69 respectively (total 54 379 samples). The total rates of anticoagulation complication and mortality were 5.79% Pty and 0.12% Pty respectively, among which the morbidity and mortality of hemorrhage were 3.59% Pty and 0.12% Pty respectively, while the morbidity and mortality of thromboembolism were 2.03% Pty and 0.00% Pty respectively. There are no significant differences of actual anticoagulation intensity (P = 0.28)and the complication rates between the two hospitals .

CONCLUSION

The optimal intensity scope (INR) of 1.5-2.5 (mean 1.8-2.0) is safe and efficient for Chinese patients with prosthetic heart valves, and no significant regional difference in the intensity of anticoagulation therapy required.

Pharmacogenetics-Based versus Conventional Dosing of Warfarin: A Meta-Analysis of Randomized Controlled Trials

Background

Recently, using the patient’s genotype to guide warfarin dosing has gained interest; however, whether pharmacogenetics-based dosing (PD) improves clinical outcomes compared to conventional dosing (CD) remains unclear. Thus, we performed a meta-analysis to evaluate these two strategies.

Methods

The PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), Chinese VIP and Chinese Wan-fang databases were searched. The Cochrane Collaboration’s tool was used to assess the risk of bias in randomized controlled trials (RCTs). The primary outcome was time within the therapeutic range (TTR); the secondary end points were the time to maintenance dose and time to first therapeutic international normalized ratio (INR), an INR greater than 4, adverse events, major bleeding, thromboembolism and death from any cause.

Results

A total of 11 trials involving 2,678 patients were included in our meta-analysis. The results showed that PD did not improve the TTR compared to CD, although PD significantly shortened the time to maintenance dose (MD = -8.80; 95% CI: -11.99 to -5.60; P<0.00001) and the time to first therapeutic INR (MD = -2.80; 95% CI: -3.45 to -2.15; P<0.00001). Additionally, PD significantly reduced the risk of adverse events (RR = 0.86; 95% CI: 0.75 to 0.99; P = 0.03) and major bleeding (RR = 0.36; 95% CI: 0.15 to 0.89, P = 0.03), although it did not reduce the percentage of INR greater than 4, the risk of thromboembolic events and death from any cause. Subgroup analysis showed that PD resulted in a better improvement in the endpoints of TTR and over-anticoagulation at a fixed initial dosage rather than a non-fixed initial dosage.

Conclusions

The use of genotype testing in the management of warfarin anticoagulation was associated with significant improvements in INR-related and clinical outcomes. Thus, genotype-based regimens can be considered a reliable and accurate method to determine warfarin dosing and may be preferred over fixed-dose regimens.

Trial Registration PROSPERO

Database registration: CRD42015024127.

Mortality outcomes in patients receiving direct oral anticoagulants: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Direct oral anticoagulants (DOACs) are widely used as an alternative for warfarin. However, the impact of DOACs on mortality outcomes compared with warfarin remains unclear.

OBJECTIVE

To estimate the mortality outcomes in patients treated with DOACs vs. warfarin (or another vitamin K antagonist).

METHODS

MEDLINE, EMBASE and CENTRAL databases (inception to September 2014), conference abstracts and www.clinicaltrials.gov, were searched, without language restriction. Studies were selected if there were phase III, randomized trials comparing DOACs with warfarin in patients with non-valvular atrial fibrillation or venous thromboembolism.

RESULTS

Thirteen randomized controlled trials involving 102 707 adult patients were included in the analysis. The case-fatality rate of major bleeding was 7.57% (95% CI, 6.53-8.68; I(2) = 0%) in patients taking DOACs and 11.04% (95% CI, 9.16-13.07; I(2) = 33.3%) in patients taking warfarin. The rate of fatal bleeding in adult patients receiving DOACs was 0.16 per 100 patient-years (95% CI, 0.12-0.20; I(2) = 36.5%). When compared with warfarin, DOACs were associated with significant reductions in fatal bleeding (RR, 0.53; 95% CI, 0.43-0.64; I(2) = 0%), cardiovascular mortality (RR, 0.88; 95% CI, 0.82-0.94; I(2) = 0%) and all-cause mortality (RR, 0.91; 95% CI, 0.87-0.96; I(2) = 0%).

CONCLUSIONS

The use of DOACs compared with warfarin is associated with a lower rate of fatal bleeding, case-fatality rate of major bleeding, cardiovascular mortality and all-cause mortality.

Assessment of the CHA2DS2-VASc Score in Predicting Ischemic Stroke, Thromboembolism, and Death in Patients With Heart Failure With and Without Atrial Fibrillation

IMPORTANCE

The CHA2DS2-VASc score (congestive heart failure, hypertension, age ≥75 years [doubled], diabetes, stroke/transient ischemic attack/thromboembolism [doubled], vascular disease [prior myocardial infarction, peripheral artery disease, or aortic plaque], age 65-75 years, sex category [female]) is used clinically for stroke risk stratification in atrial fibrillation (AF). Its usefulness in a population of patients with heart failure (HF) is unclear.

OBJECTIVE

To investigate whether CHA2DS2-VASc predicts ischemic stroke, thromboembolism, and death in a cohort of patients with HF with and without AF.

DESIGN, SETTING, AND POPULATION

Nationwide prospective cohort study using Danish registries, including 42 987 patients (21.9% with concomitant AF) not receiving anticoagulation who were diagnosed as having incident HF during 2000-2012. End of follow-up was December 31, 2012.

EXPOSURES

Levels of the CHA2DS2-VASc score (based on 10 possible points, with higher scores indicating higher risk), stratified by concomitant AF at baseline. Analyses took into account the competing risk of death.

MAIN OUTCOMES AND MEASURES

Ischemic stroke, thromboembolism, and death within 1 year after HF diagnosis.

RESULTS

In patients without AF, the risks of ischemic stroke, thromboembolism, and death were 3.1% (n = 977), 9.9% (n = 3187), and 21.8% (n = 6956), respectively; risks were greater with increasing CHA2DS2-VASc scores as follows, for scores of 1 through 6, respectively: (1) ischemic stroke with concomitant AF: 4.5%, 3.7%, 3.2%, 4.3%, 5.6%, and 8.4%; without concomitant AF: 1.5%, 1.5%, 2.0%, 3.0%, 3.7%, and 7% and (2) all-cause death with concomitant AF: 19.8%, 19.5%, 26.1%, 35.1%, 37.7%, and 45.5%; without concomitant AF: 7.6%, 8.3%, 17.8%, 25.6%, 27.9%, and 35.0%. At high CHA2DS2-VASc scores (≥4), the absolute risk of thromboembolism was high regardless of presence of AF (for a score of 4, 9.7% vs 8.2% for patients without and with concomitant AF, respectively; overall P<.001 for interaction). C statistics and negative predictive values indicate that the CHA2DS2-VASc score performed modestly in this HF population with and without AF (for ischemic stroke, 1-year C statistics, 0.67 [95% CI, 0.65-0.68] and 0.64 [95% CI, 0.61-0.67], respectively; 1-year negative predictive values, 92% [95% CI, 91%-93%] and 91% [95% CI, 88%-95%], respectively).

CONCLUSIONS AND RELEVANCE

Among patients with incident HF with or without AF, the CHA2DS2-VASc score was associated with risk of ischemic stroke, thromboembolism, and death. The absolute risk of thromboembolic complications was higher among patients without AF compared with patients with concomitant AF at high CHA2DS2-VASc scores. However, predictive accuracy was modest, and the clinical utility of the CHA2DS2-VASc score in patients with HF remains to be determined.

Long-term Prognosis of Paroxysmal Atrial Fibrillation and Predictors for Progression to Persistnt or Chronic Atrial Fibrillation in the Korean Population

Little is known about the long-term prognosis of or predictors for the different clinical types of atrial fibrillation (AF) in Korean populations. The aim of this study was to validate a risk stratification to assess the probability of AF progression from paroxysmal AF (PAF) to persistent AF (PeAF) or permanent AF. A total of 434 patients with PAF were consecutively enrolled (mean age; 71.7 ± 10.7 yr, 60.6% male). PeAF was defined as episodes that are sustained > 7 days and not self-terminating, while permanent AF was defined as an ongoing long-term episode. Atrial arrhythmia during follow-up was defined as atrial premature complex, atrial tachycardia, and atrial flutter. During a mean follow-up of 72.7 ± 58.3 months, 168 patients (38.7%) with PAF progressed to PeAF or permanent AF. The mean annual AF progression was 10.7% per year. In univariate analysis, age at diagnosis, body mass index, atrial arrhythmia during follow-up, left ventricular ejection fraction, concentric left ventricular hypertrophy, left atrial diameter (LAD), and severe mitral regurgitation (MR) were significantly associated with AF progression. In multivariate analysis, age at diagnosis (P = 0.009), atrial arrhythmia during follow-up (P = 0.015), LAD (P = 0.002) and MR grade (P = 0.026) were independent risk factors for AF progression. Patients with younger age at diagnosis, atrial arrhythmia during follow-up, larger left atrial chamber size, and severe MR grade are more likely to progress to PeAF or permanent AF, suggesting more intensive medical therapy with close clinical follow-up would be required in those patients.

Effects of body mass index on risks for ischemic stroke, thromboembolism, and mortality in Chinese atrial fibrillation patients: a single-center experience

Background

Obesity is considered to be related to recurrence of atrial fibrillation (AF), left atrial thrombus formation, and atrial remodeling. However, whether obesity is an independent risk factor for stroke and other thromboembolic events is still controversial.

Objective

This study aimed to investigate the effects of body mass index (BMI) on the risks of stroke, thromboembolism, and mortality in AF patients.

Methods

Patients who were diagnosed with nonvalvular AF were included in this observational, retrospective study. The study population was stratified by BMI at baseline. The Cox proportional hazard model was adopted to calculate adjusted hazard ratios of risk factors for adverse clinical events (stroke, thromboembolism, and mortality).

Results

A total of 1286 AF patients (males, 78.30%; mean age, 74.50 years; 94.48% paroxysmal AF) were followed up for a median of 2.1 years (IQR: 1.5–2.9 years). Overall, 159 patients died. A total of 84 strokes and 35 thromboembolic events occurred. Multivariate analysis showed that overweight (25.0≤BMI<30.0 kg/m²) and age ≥75 years were independent risk factors for ischemic stroke (both P<0.01). Obesity (BMI ≥30.0 kg/m²), age ≥75 years, persistent/permanent AF, and prior thromboembolism were independent risk factors for thromboembolism (all P<0.05). Underweight (BMI <18.5 kg/m²), age ≥75 years, prior ischemic stroke/transient ischemic attack, renal dysfunction, and heart failure were independent risk factors for all-cause deaths (all P<0.05).

Conclusions

Overweight or obesity may be a risk factor of ischemic stroke and thromboembolism in AF patients. Excessive low weight is significantly associated with increased all-cause mortality.

Sex differences in treatment quality of self-managed oral anticoagulant therapy: 6,900 patient-years of follow-up

Background

Patient-self-management (PSM) of oral anticoagulant therapy with vitamin K antagonists has demonstrated efficacy in randomized, controlled trials. However, the effectiveness and efficacy of PSM in clinical practice and whether outcomes are different for females and males has been sparsely investigated.The objective is to evaluate the sex-dependent effectiveness of PSM of oral anticoagulant therapy in everyday clinical practice.

Methods

All patients performing PSM affiliated to Aarhus University Hospital and Aalborg University Hospital, Denmark in the period 1996–2012 were included in a case-series study. The effectiveness was estimated using the following parameters: stroke, systemic embolism, major bleeding, intracranial bleeding, gastrointestinal bleeding, death and time spent in the therapeutic international normalized ratio (INR) target range. Prospectively registered patient data were obtained from two databases in the two hospitals. Cross-linkage between the databases and national registries provided detailed information on the incidence of death, bleeding and thromboembolism on an individual level.

Results

A total of 2068 patients were included, representing 6,900 patient-years in total. Males achieved a significantly better therapeutic INR control than females; females spent 71.1% of the time within therapeutic INR target range, whereas males spent 76.4% (p<0.0001). Importantly, death, bleeding and thromboembolism were not significantly different between females and males.

Conclusions

Among patients treated with self-managed oral anticoagulant therapy, males achieve a higher effectiveness than females in terms of time spent in therapeutic INR range, but the incidence of major complications is low and similar in both sexes.

Thromboembolism, major bleeding and mortality in patients with mechanical heart valves- a population-based cohort study

INTRODUCTION

Low incidences of thromboembolism (TE) and bleeding in patients with mechanical heart valves (MHV) have previously been reported. This study assesses the incidence of and clinical risk factors predicting TE, major bleeding and mortality in a clinical setting.

METHODS AND RESULTS

All 546 patients undergoing anticoagulation treatment due to MHV replacement at hospitals in Malmö and Sundsvall in Sweden were monitored during 2008-2011 and the incidence of TE, major bleeding and mortality was prospectively followed. There were 398, 122 and 26 patients in the aortic group (AVR), mitral (MVR) group and the combined aortic/mitral valve group respectively. The incidence of TE was 1.8 and 2.2 per 100 patient-years in the AVR group MVR group respectively. The corresponding incidences of bleeding were 4.4 and 4.6, respectively. Independent predictor of thromboembolism was vascular disease (Odds ratio {OR}: 4.2; 95% CI: 1.0-17.4). Predictor of bleeding was previous bleeding (OR: 2.7; 95% CI: 1.4-5.3). Independent predictors of mortality was age (Hazard ratio {HR}: 1.03; 95% CI: 1.00-1.05), hypertension (HR: 2.4; 95% CI: 1.3-4.5), diabetes (HR: 2.4; 95% CI: 1.3-4.3) and alcohol overconsumption (HR: 5.2; 95% CI: 1.7-15.9). Standardized mortality/morbidity ratio for mortality and AMI was 0.99 (95% CI: 0.8-1.2) and 0.87 (95% CI: 0.5-1.2) respectively.

CONCLUSION

The incidence of TE and major bleeding in this unselected clinical population exceeds that of previously reported retrospective and randomized trials. Despite this, mortality is equal to that of the general population.

Comparison of idrabiotaparinux with vitamin K antagonists for prevention of thromboembolism in patients with atrial fibrillation: the Borealis-Atrial Fibrillation Study

BACKGROUND

Idrabiotaparinux, a long-acting inhibitor of factor Xa, was shown to be effective in the treatment of patients with venous thromboembolism.

OBJECTIVE

To assess non-inferiority for the efficacy of idrabiotaparinux versus warfarin in patients with atrial fibrillation (AF) at risk of stroke and systemic embolism. Bleeding was also assessed.

METHODS

This randomized, double-blind trial enrolled patients with electrocardiogram-documented AF. Idrabiotaparinux was administered weekly via subcutaneous injection, and warfarin was administered daily with dose adjustment to maintain the international normalized ratio between 2.0 and 3.0. Each idrabiotaparinux injection was 3 mg for the first 7 weeks, followed by 2 mg thereafter, except in patients with a creatinine clearance of 30-50 mL min(-1) or aged ≥ 75 years. The patients received 1.5 mg after the first 7 weeks. The efficacy outcome was the composite of all fatal or non-fatal strokes and systemic embolism. The safety outcome was clinically relevant bleeding (major and clinically relevant non-major bleeding).

RESULTS

The study was terminated prematurely by the sponsor for strategic/commercial, not scientific, reasons, with 39% of the planned number of patients included and an average duration of treatment of 240 days. Of the 1886 idrabiotaparinux recipients, 20 developed stroke or systemic embolism (1.5% per year), whereas this occurred in 22 of the 1887 warfarin patients (1.6% per year, hazard ratio 0.98, 95% confidence interval 0.49-1.66). The annual incidence of bleeding was 6.1% in the idrabiotaparinux and 10.0% in the warfarin group (hazard ratio 0.61, 95% confidence interval 0.46-0.81).

CONCLUSION

If anything, despite its early termination, the idrabiotaparinux regimen studied suggested a comparable efficacy to dose-adjusted warfarin, with a lower bleeding risk.