Atrial Thrombosis Prevalence Before Cardioversion or Catheter Ablation of Atrial Fibrillation: An Updated Systematic Review and Meta-Analysis of Direct Oral Anticoagulants Versus Vitamin K Antagonists

Left atrial or left atrial appendage thrombosis (LAT) is contraindicated for cardiac ablation (CA) or cardioversion (CV) of atrial fibrillation (AF). This study was aimed to compare the frequency of LAT detected by transesophageal echocardiography (TEE) before CA or CV in patients with AF treated with direct oral anticoagulants (DOACs) or vitamin K antagonists (VKAs). We searched PubMed, Scopus, Web of Science, and Cochran Library databases from inception through July 13, 2023 to select studies reporting data on LAT identification before CA or CV using TEE in patients with AF treated with DOACs or VKAs. Pooled odds ratios (ORs) with 95% confidence interval were calculated with a random-effects model. Studies retrieved were 50 (38 observational), 29 on CA, 15 on CV, and 6 on both procedures (17,096 patients on DOACs and 13,666 on VKAs). The overall prevalence of LAT was smaller in DOACs than in VKAs, with an OR of 0.66 (0.52 to 0.84), confirmed at sensitivity analysis and in most subgroups. This finding was consistent for the 3 most reported DOACs: the pooled OR for LAT was 0.68 (0.50 to 0.90) in apixaban, 0.67 (0.51 to 0.88) in dabigatran, 0.61 (0.43 to 0.89) in rivaroxaban, and 1.10 (0.74 to 1.64) in edoxaban (not significant). In conclusion, in this large meta-analysis in patients with AF, the prevalence of LAT by TEE evaluation performed before CV or CA appears lower in those treated with DOACs than in those on VKAs. Additional research may help in better understanding differences between these classes of anticoagulant drugs in the setting of protection against AF-related left atrial thrombotic formation.

Real-world experience of direct oral anticoagulant use in a single pediatric center

BACKGROUND

Pediatric venous thromboembolism has increased by 130%-200%, specifically in hospitalized children, and direct oral anticoagulants (DOACs) offer several therapeutic advantages.

METHODS

This study aims to evaluate the real-world epidemiological and outcome data from a retrospective review of pediatric patients treated with DOACs from January 1, 2013 to December 31, 2022. In this single-center, IRB-approved study, 65 patients were identified and analyzed using SPSS statistical software, and a descriptive statistical analysis was conducted.

RESULTS

Of the 65 patients, 37% were on apixaban, 61.5% were on rivaroxaban, and 1.5% were on dabigatran. Per the 2023 ISTH outcome definitions, one (2%) patient had a major bleeding episode, six (9%) had clinically relevant non-major bleeding, three (5%) patients had patient-important heavy menstrual bleeding (HMB), and one (1.5%) patient had minor bleeding. Seven (19%) of 37 postmenarchal patients had evidence of HMB. Six (9.2%) patients had recurrent venous thromboembolism while on a DOAC (one was on apixaban, and five were on rivaroxaban) and were transitioned to other forms of anticoagulation.

CONCLUSION

Thus, bleeding rates after DOAC therapy are comparable to previous DOAC trials, as well as other anticoagulants in pediatrics. HMB is an important outcome measure and should continue to be investigated. This study reports a higher rate of recurrent thrombosis (9.2%) compared to other trials. However, this observation may be attributed to patients who had ongoing risk factors, as well as a longer duration of study follow-up. Additional multicentered outcome studies evaluating DOAC use in children are needed to determine long-term recurrence and HMB risks.

Clinical Surveillance vs Anticoagulation Therapy for Isolated Subsegmental Pulmonary Embolism: A Systematic Review of Clinical Outcomes

BACKGROUND

This systematic review aims to evaluate and compare differences in clinical outcomes for adult patients diagnosed with ISSPE who were managed with anticoagulation vs clinical surveillance.

METHODS

PubMed, Embase, ProQuest, Cochrane, and Google Scholar were searched to identify studies evaluating the use of anticoagulation and/or clinical surveillance in patients diagnosed with ISSPE. The search included studies published up to August 3, 2023. Outcomes of interest included 90-day recurrent venous thromboembolism (VTE), major bleeding, and all-cause mortality rates.

RESULTS

Ten studies were included with a total of 1224 patients. Of these patients, 791 were treated with anticoagulation and 433 underwent surveillance. Studies found no difference in recurrent VTE rates, with the majority of studies reporting no recurrence. Of the studies that reported VTE recurrence, rates were .5% to 1.4% for the anticoagulation groups and 3.1% to 3.2% for the surveillance groups. Major bleeding rates were also similar. In anticoagulated patients, major bleeding rates ranged from 1% to 10%. In clinical surveillance patients, the majority found no rate of major bleeding, with 2 studies reporting rates of .8% to 3.2%. Mortality rates ranged widely with no significant differences reported.

CONCLUSION

Clinical surveillance appears to be a safe and effective alternative to anticoagulation in patients with ISSPE. Ninety-day rates of recurrent VTE, major bleeding, and mortality were comparable between groups. These findings highlight the need for updated practice management guidelines to improve patient outcomes.

Safety and Efficacy of Enoxaparin During Low-Risk Elective Percutaneous Coronary Intervention

Intravenous unfractionated heparin (UFH) is the most frequently used anticoagulant for percutaneous coronary intervention (PCI). Intravenous enoxaparin, a low-molecular-weight heparin, has superior pharmacokinetic and pharmacodynamic properties compared with UFH. Multiple trials have shown enoxaparin to be safe and effective in PCI. However, there has not been a contemporary study evaluating its safety and efficacy. To assess its efficacy and safety, intravenous enoxaparin during PCI through radial artery access was evaluated in PCI patients from January 2015 to December 2019. Outcomes included procedural success, all-cause mortality, ischemic complications, and bleeding complications from the time of the procedure until hospital discharge. A total of 1019 consecutive eligible patients were identified. Median age was 63 years, and 70% were men. The indication for PCI was stable and unstable angina in two-thirds of cases (77%). Few patients had myocardial infarction (MI) (2.2%) as the indication for intervention. The procedure was successful in 98.2% of cases. There were no deaths. Procedural MI occurred in 0.3% of patients. Acute stent thrombosis occurred in 0.4%. Urgent revascularization and stroke occurred in 0.1% each. Small wrist hematomas occurred in 0.3% and all were managed conservatively. There was one radial artery pseudoaneurysm. There were no cases of major bleeding. In conclusion, this single-center study showed that intravenous enoxaparin is a reasonable alternative anticoagulant for use in low-risk and elective non-MI PCI through radial artery access.

The efficacy and safety of direct oral anticoagulants in the treatment of the acute phase of heparin-induced thrombocytopenia: A systematic review

DISCLAIMER

In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

PURPOSE

To investigate the safety and efficacy of direct oral anticoagulants (DOACs) in the treatment of the acute phase of heparin-induced thrombocytopenia (HIT).

SUMMARY

A systematic review of the literature was conducted on PubMed, MEDLINE, Embase, and Web of Science Core Collection through July 2023. Search terms included "heparin-induced thrombocytopenia AND direct-oral-anticoagulants" in addition to a list of oral anticoagulants. Adult patients who used direct oral anticoagulants as the initial treatment for the acute phase of HIT were included. A total of 1,188 articles were initially identified, with 770 articles reviewed following removal of duplicates. Following the application of inclusion and exclusion criteria, 12 articles were ultimately included. Rivaroxaban was the most-utilized DOAC (28 patients), followed by apixaban (7 patients) and dabigatran (1 patient). All patients with thrombocytopenia demonstrated successful platelet recovery, with two patients presenting with normal platelet counts. One patient developed a deep venous thrombosis with no other new or recurrent thromboses. There were no reported clinically significant adverse events in any patient. Obstacles and deterrents to the use of the standards of care in the acute phase of HIT exist. Argatroban and bivalirudin require intravenous infusion and require close aPTT monitoring and dose adjustment. Fondaparinux requires injection and is contraindicated with body weight <50kg. DOACs would offer the novel ability for an oral treatment in the treatment of the acute phase HIT and allow for minimal monitoring and consistent dosing strategies. Therefore, DOACs are an intriguing choice for the treatment of the acute phase of HIT.

CONCLUSION

Data from 12 publications and across 36 patients suggests that the use of DOACs in the acute phase of HIT may be a safe and efficacious treatment option with favorable ease of monitoring and management.

Pharmacist-led interventions in optimising the use of oral anticoagulants in patients with atrial fibrillation in general practice in England: a retrospective observational study

BACKGROUND

Oral anticoagulation (OAC) is the mainstay of treatment for the prevention of strokes in patients with atrial fibrillation (AF). Direct oral anticoagulants (DOACs) account for increasing OAC in patients with AF. However, prescribing DOACs for patients with established AF poses various challenges and general practice pharmacists may have an important role in supporting their management.

AIM

To investigate the effectiveness of pharmacist-led interventions in general practice in optimising the use of OAC therapies in AF.

DESIGN & SETTING

A retrospective observational study in general practices in Bradford.

METHOD

The data were collected retrospectively from 1 November 2018-31 December 2019 using electronic health record data. The data were analysed: 1) to identify patients with AF not on OAC; 2) to describe inappropriate DOAC prescriptions; and 3) to calculate HAS-BLED scores.

RESULTS

Overall, 76.3% (n = 470) of patients with AF received OAC therapy, and of these, 63.4% received DOACs. Pharmacist-led interventions increased DOAC prescribing by 6.0% (P = 0.03). Inappropriate DOAC use was identified in 24.5% of patients with AF, with underdosed and overdosed identified in 9.7% and 14.8%, respectively. Post-intervention, inappropriate prescribing was reduced to 1.7%. The mean HAS-BLED score decreased from 3.00 to 2.22 (P<0.01). Successful transition from vitamin K antagonist (VKA) therapy to DOACs was achieved in 25.7% of patients.

CONCLUSION

Pharmacist-led interventions have successfully improved the use of OAC therapies in patients with AF, and effectively managed the bleeding risks and transition from VKA to DOAC therapy, in line with guidelines.

Anticoagulation for Patients With Concomitant Atrial Fibrillation and End-Stage Renal Disease: A Systematic Review and Network Meta-Analysis

BACKGROUND

Concomitant atrial fibrillation and end-stage renal disease is common and associated with an unfavorable prognosis. Although oral anticoagulants have been well established to prevent thromboembolism, the applicability in patients under long-term dialysis remains debatable. The study aimed to determine the efficacy and safety of anticoagulation in the dialysis-dependent population.

METHODS AND RESULTS

An updated network meta-analysis based on MEDLINE, EMBASE, and the Cochrane Library was performed. Studies published up to December 2022 were included. Direct oral anticoagulants (DOACs, dabigatran, rivaroxaban, apixaban 2.5/5 mg twice daily), vitamin K antagonists (VKAs), and no anticoagulation were compared on safety and efficacy outcomes. The outcomes of interest were major bleeding, thromboembolism, and all-cause death. A total of 42 studies, including 3 randomized controlled trials, with 185 864 subjects were pooled. VKAs were associated with a significantly higher risk of major bleeding than either no anticoagulation (hazard ratio [HR], 1.47; 95% CI, 1.34-1.61) or DOACs (DOACs versus VKAs; HR, 0.74 [95% CI, 0.64-0.84]). For the prevention of thromboembolism, the efficacies of VKAs, DOACs, and no anticoagulation were equivalent. Nevertheless, dabigatran and rivaroxaban were associated with fewer embolic events. There were no differences in all-cause death with the administration of VKAs, DOACs, or no anticoagulation.

CONCLUSIONS

For dialysis-dependent populations, dabigatran and rivaroxaban were associated with better efficacy, while dabigatran and apixaban demonstrated better safety. No anticoagulation was a noninferior alterative, and VKAs were associated with the worst outcomes.

Oral anticoagulant prescribing among patients with cancer and atrial fibrillation in England, 2009-2019

BACKGROUND

Anticoagulation of patients with atrial fibrillation (AF) and cancer is challenging because of their high risk for stroke and bleeding. Little is known of the variations of oral anticoagulant (OAC) prescribing in patients with AF with and without cancer.

METHODS

Patients with first-time AF during 2009-2019 from the Clinical Practice Research Datalink were included. Cancer diagnosis was defined as a history of breast, prostate, colorectal, lung, or hematological cancer. Competing-risk analysis was used to assess the risk of OAC prescribing in patients with AF and cancer adjusted for clinical and sociodemographic factors.

RESULTS

Of 177,065 patients with AF, 11.7% had cancer. Compared to patients without cancer, patients with cancer were less likely to receive OAC: prostate cancer (subhazard ratio [SHR], 0.95; 95% CI, 0.91-0.99), breast cancer (SHR, 0.93; 95% CI, 0.89-0.98), colorectal cancer (SHR, 0.93; 95% CI, 0.88-0.99), hematological cancer (SHR, 0.70; 95% CI, 0.65-0.75), and lung cancer (SHR, 0.44; 95% CI, 0.38-0.50). The cumulative incidence function (CIF) of OAC prescribing was lowest for patients with lung cancer and hematological cancer compared with patients without cancer. The difference between the CIF of OAC prescribing in patients with and without cancer becomes narrower in the most deprived areas. Elderly patients (aged ≥85 years) overall had the lowest CIF of OAC prescribing regardless of cancer status.

CONCLUSIONS

In patients with AF, underprescribing of OAC is independently associated with certain cancer types. Patients with hematological and lung cancer are the least likely to receive anticoagulation therapy compared with patients without cancer. Underprescribing of OAC in cancer is linked to old age. Further studies of patients with AF and cancer are warranted to assess the net clinical benefit of anticoagulation in certain cancer types.

On-X aortic valve replacement patients treated with low dose warfarin and low dose aspirin

OBJECTIVES

To assess if warfarin targeted to INR 1.8 (range 1.5-2.0) is safe for all patients with an On-X aortic mechanical valve.

METHODS

This prospective, observational registry follows patients receiving warfarin targeted at an INR of 1.8 (range 1.5-2.0) plus daily aspirin (75-100 mg) after On-X aortic valve replacement. The primary end-point is a composite of thromboembolism, valve thrombosis, and major bleeding. Secondary end-points include the individual rates of thromboembolism, valve thrombosis, and major bleeding, as well as the composite in subgroups of home or clinic-monitored INR and risk categorization for thromboembolism. The control was the patient group randomized to standard-dose warfarin (INR 2.0-3.0) plus daily aspirin 81 mg from the PROACT trial.

RESULTS

A total of 510 patients were enrolled at 23 centers in the UK, United States, and Canada. Currently, the median follow-up duration is 3.4 years, and median achieved INR is 1.9. The primary composite end-point rate in the low INR patients is 2.31% vs 5.39% (95% confidence interval 4.12%-6.93%) per patient-year in the PROACT control group, constituting a 57% reduction. Results are consistent in subgroups of home or clinic-monitored, and high-risk patients, with reductions of 56%, 57%, and 57%, respectively. Major and total bleeding are decreased by 85% and 73%, respectively, with similar rates of thromboembolic events. No valve thrombosis occurred.

CONCLUSIONS

Interim results suggest that warfarin targeted at an INR of 1.8 (range 1.5-2.0) plus aspirin is safe and effective in patients with an On-X aortic mechanical valve with or without home INR monitoring.

Pharmacological Thromboprophylaxis for VTE Post-Endovenous Ablation of Varicose Veins: Network Meta-Analysis

OBJECTIVE

Endovenous ablation has revolutionized treatment of varicose vein surgery but is associated with a risk of venous thromboembolism. There is no consensus regarding anticoagulation protocols for these patients. This network meta-analysis (NMA) aims to identify which anticoagulant is optimal in this cohort for clot prevention with minimal risk of adverse bleeding events.

METHODS

Library databases were searched for studies where patients were treated with one or more anticoagulants following endovenous ablation for varicose veins. The methodological quality of included studies was quantified using the Risk of Bias (ROB) assessment tools. Findings were reported using the meta-analysis of observational studies in epidemiology (MOOSE) checklist. Statistical analysis was carried out using metainsight (rpackage).

RESULTS

Observational data on just under 1500 patients prescribed post ablation anticoagulation (Rivaroxaban, Enoxaparin, Fondaparinux) were analyzed. Patient characteristics were comparable across the cohorts. 81 thrombotic and 40 minor bleeding events occurred in total. Overall rivaroxaban is found to be superior to the other agents.

CONCLUSIONS

This NMA indicates that prophylactic rivaroxaban is the highest ranked anticoagulant for thromboprophylaxis in patients post endovenous ablation for varicose veins, with a low risk of adverse bleeding. The choice whether to anticoagulate these patients is likely to remain at the discretion of the treating clinician.

Ultrasound elastography predicts anticoagulation in lower extremity deep vein thrombosis

OBJECTIVE

To investigate predictors of anticoagulation efficacy in deep venous thrombosis (DVT) by ultrasound elastography (UE).

METHODS

The basic clinical, laboratory and ultrasound treatment data of fifty-eight patients with DVT were collected and analyzed. Then the results of ultrasound after 3-month anticoagulation treatment were compared among different groups. Multiple logistic regression analysis was used to identify independent risk factors that affected anticoagulation efficacy. The predictive efficacy of each independent risk factor was accessed by drawing operating characteristic (ROC) curves.

RESULTS

According to the regression analysis, the elastic modulus (OR = 0.631, P = 0.001) and strain rate ratio (OR = 0.332, P = 0.006) were identified as independent risk factors for the effectiveness of anticoagulation therapy in patients with DVT. According to the ROC curves, elastic modulus and strain rate ratio could predict effective anticoagulation therapy for DVT, and the optimal threshold values were 22.10 kPa and 1.80 respectively. The corresponding AUC values were 0.879 and 0.854, with a sensitivity of 71.4% and 59.5%, a specificity of 93.7%, and a Youden index of 65.1% and 62.7%, respectively.

CONCLUSIONS

The elastic modulus (≤22.10 kPa) or strain rate ratio (≤1.80) of the thrombus were independent predictors for the effectiveness of anticoagulation therapy.

Anticoagulation in patients with premature peripheral artery disease undergoing lower extremity revascularization

OBJECTIVES

Premature peripheral artery disease (PAD), defined by lower extremity revascularization (LER) at age ≤ 50 years, is associated with poor major adverse limb events. The early onset of disease is thought to be influenced by genetic factors that regulate homeostasis of the vascular wall and coagulation. The aim of this study is to investigate the effect of anticoagulation as an adjunct to antiplatelet therapy on the outcomes of LER in patients with premature PAD.

METHODS

There were 8,804 patients with premature PAD on pre- and post-operative antiplatelet therapy only and 1,236 patients on pre- and post-operative anticoagulation plus antiplatelet therapy in the Vascular Quality Initiative (VQI) peripheral vascular intervention, infra-, and suprainguinal files. Propensity score matching (2:1) was performed between patients with premature PAD who were on antiplatelet therapy and those on anticoagulation plus antiplatelet therapy. Perioperative and one-year outcomes were analyzed including reintervention, major amputation, and mortality.

RESULTS

Patients on anticoagulation were more likely to have coronary artery disease (48.7% vs 41.2%, P<.001), congestive heart failure (20.2% vs 13.1%, P<.001), and have undergone prior LER (73.9% vs 49.2%, P<.001) compared to patients on antiplatelet therapy only. They were also less likely to be independently ambulatory (74.2% vs 81.8%, P<.001) and be on a statin medication (66.8% vs 74.3%, P<.001) compared to patients on antiplatelet therapy only. Patients on anticoagulation were also less likely to be treated for claudication (38.1% vs 48.6%, P<.001), and less likely to be treated with an endovascular procedure (64.8% vs 73.8%, P<.001). After matching for baseline characteristics, there were 1,256 patients on antiplatelet therapy only and 628 patients on anticoagulation. Patients on anticoagulation were more likely to require a return to the operating room (3.7% vs 1.6%, P<.001) and had higher perioperatively mortality (1.1% vs 0.3%, P=.032), but major amputation was not significantly different (1.8% vs 1.6%, P=.798) compared to patients on antiplatelet therapy alone. At one-year, amputation-free survival was higher in patients on antiplatelets only compared to patients on anticoagulation and antiplatelet medications (87.5% vs 80.9%, log-rank P=.001).

CONCLUSION

Anticoagulation in addition to antiplatelet therapy in patients with premature PAD undergoing lower extremity revascularization is associated with increased reintervention and mortality at one year.

Effect of anticoagulation on the incidence of venous thromboembolism, major bleeding, and mortality among hospitalized COVID-19 patients: an updated meta-analysis

Objective

Anticoagulation is crucial for patients hospitalized with coronavirus disease 2019 (COVID-19) due to the high risk of venous thromboembolism (VTE). However, the optimal anticoagulation regimen needs further exploration. Therefore, we evaluated the efficacy and safety of diverse anticoagulation dosage dosages for COVID-19.

Methods

An updated meta-analysis was performed to assess the effect of thromboprophylaxis (standard, intermediate, and therapeutic dose) on the incidence of VTE, mortality and major bleeding among COVID-19 patients. Literature was searched via PubMed, EMBASE, Web of Science, and China National Knowledge Infrastructure (CNKI) database. The odds ratio (OR) and 95% confidence interval (CI) were calculated for effect estimates.

Results

Nineteen studies involving 25,289 participants without VTE history were included. The mean age of patients was 59.3 years old. About 50.96% were admitted to the intensive care unit. In the pooled analysis, both therapeutic-dose and intermediate-dose anticoagulation did not have a significant advantage in reducing VTE risk over standard dosage (OR = 1.09, 95% CI: 0.58-2.02, and OR = 0.89, 95% CI: 0.70-1.12, respectively). Similarly, all-cause mortality was not further decreased in either therapeutic-dose group (OR = 1.12, 95% CI: 0.75-1.67) or intermediate-dose group (OR = 1.34, 95% CI: 0.83-2.17). While the major bleeding risk was significantly elevated in the therapeutic-dose group (OR = 2.59, 95%CI: 1.87-3.57) as compared with the standard-dose regimen. Compared with intermediate dosage, therapeutic anticoagulation did not reduce consequent VTE risk (OR = 0.85, 95% CI: 0.52-1.38) and all-cause mortality (OR = 0.84, 95% CI: 0.60-1.17), but significantly increased major bleeding rate (OR = 2.42, 95% CI: 1.58-3.70). In subgroup analysis of patients older than 65 years, therapeutic anticoagulation significantly lowered the incidence of VTE in comparation comparison with standard thromboprophylaxis, however, at the cost of elevated risk of major bleeding.

Conclusion

Our results indicated that for most hospitalized patients with COVID-19, standard-dose prophylactic anticoagulation might be the optimal choice. For elderly patients at low risk of bleeding, therapeutic-dose anticoagulation could further reduce VTE risk and should be considered especially when there were other strong risk factors of VTE during hospital stay.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO, identifier, CRD42023388429.

Advances and current research in primary thromboprophylaxis to prevent hospital-associated venous thromboembolism

Hospital-associated venous thromboembolism (VTE) is defined as any case of VTE occurring during hospital admission and for up to 90 days post discharge. It accounts for over 50% of all cases of VTE internationally; indeed, there are an estimated 10 million cases of hospital-associated VTE annually. Over the last decade, there has been increasing interest in improving VTE risk assessment and thromboprophylaxis. This review summarises all the recent and ongoing major research studies and future challenges in the different areas, including medical, surgical and obstetric patients, as well as special areas such as lower limb immobilisation. We include sections on both pharmacological and mechanical thromboprophylaxis.

Deep venous thrombosis in patients with atresia of the inferior vena cava and right kidney hypoplasia (KILT syndrome): Systematic review of the literature

Inferior vena cava (IVC) anomalies are uncommon congenital causes of deep vein thrombosis (DVT). KILT syndrome (kidney and IVC abnormalities with leg thrombosis) has only been described as case reports in the literature. Therefore, the characteristics, evaluation, and management of patients with KILT syndrome have not yet been standardized. This study aimed to systematically review and analyze the clinical and radiographic data and treatment of previously reported cases of KILT syndrome. In this systematic review, we performed a literature search of the PubMed, Scopus, and Web of Science databases in December 2023, with no restrictions on the publication date. After duplicate extractions, 4195 articles were screened. Case reports and case series reporting on KILT syndrome were included. In addition to previously published cases, we included a new case of a previously healthy 25-year-old man with KILT syndrome in the analysis. A total of 34 cases were therefore included in this study. The majority (76.5%) were male patients with a median age of 24 years. In most patients, unprovoked bilateral iliofemoral thrombosis was diagnosed, and 64.7% had left kidney abnormalities. Our study suggests that anomalies of the IVC should be suspected in all young patients, especially male patients, with proximal, recurrent, or idiopathic DVT. If an IVC anomaly is confirmed, the kidneys should be examined to monitor and preserve healthy kidneys in cases of KILT syndrome. The data collected from all patients emphasize the requirement of long-term anticoagulation and risk factor control. Surgical measures may be effective for treating symptomatic refractory cases.

Managing venous thrombosis in a pediatric patient with short bowel and congenital nephrotic syndromes: a case report emphasizing rivaroxaban level monitoring

Direct Oral Anticoagulants (DOACs) typically exhibit a predictable pharmacokinetic and pharmacodynamic response at a fixed dose, not necessitating monitoring under standard conditions. Yet, in specific clinical scenarios that can impair it, like Congenital Nephrotic Syndrome (CNS) or Short Bowel Syndrome (SBS) due to absorption issues, anti-thrombin III (AT-III) deficiency and non-selective proteinuria, adjusting the dosage to achieve appropriate plasma concentrations could prove beneficial. We report a 3-month-old female with catheter-related jugular thrombosis affected by CNS concomitant to SBS and failure of both treatments with heparin and warfarin, that was switched to dose-adjusted pediatric rivaroxaban. Rivaroxaban was adjusted to reach peak levels between 189 and 419 ng/ml and the lower trough levels between 6 and 87 ng/ml. Increasing doses were needed due to SBS related malabsorption but a complete permeabilization of the vein was achieved without bleeding complications. The use of anti-Xa adjusted rivaroxaban could be an alternative to improve anticoagulation and secondary thromboprophylaxis in pediatric patients SBS and an option to children with CNS.

Association of anesthetic modality and other variables on 1-year functional patency of cephalic-based arteriovenous fistulae

OBJECTIVES

Some studies suggest that regional (RA) provides better patency for arteriovenous fistula (AVF) for hemodialysis (HD) access as compared to Local (LA) and General Anesthesia (GA). This study evaluates the impact of anesthetic modality on long term fistula function at 12 months.

METHODS

A retrospective review of patients undergoing cephalic vein-based HD access in consecutive cases between 2014 and 2019 was conducted from five safety net hospitals. The primary endpoint was functional patency at 12 months. Subset analysis individually evaluated cephalic based lower forearm and wrist versus upper arm AVFs. Bivariate and multivariate logistic regression models evaluated the relationship between anesthetic modality and fistula function at 12 months.

RESULTS

There were 818 cephalic based fistulas created during the study period. The overall 12-month functional patency rate was 78.7%, including an 81.3% patency for upper arm AVF and 73.3% for wrist AVF (p=0.009). There was no statistically significant difference among patients with functional and nonfunctional AVFs at 12 months with respect to anesthetic modality when comparing regional, local, and general anesthesia (p=0.343). Multivariate regression analysis identified that history of AVF/AVG (OR 0.24, p=0.007), receiving intraoperative systemic anticoagulation (OR 2.49, p<0.001), and vein diameter (OR 1.85, p=0.039) as independently associated with AVF functional patency at 12 months.

CONCLUSION

There was no association between anesthetic modality and functional patency of cephalic based-AVF at 12 months. Further studies are needed to better define which patients may benefit from regional anesthesia.

Developing a machine learning model for bleeding prediction in patients with cancer-associated thrombosis receiving anticoagulation therapy

BACKGROUND

Only 1 conventional score is available for assessing bleeding risk in patients with cancer-associated thrombosis (CAT): the CAT-BLEED score.

OBJECTIVES

Our aim was to develop a machine learning-based risk assessment model for predicting bleeding in CAT and to evaluate its predictive performance in comparison to that of the CAT-BLEED score.

METHODS

We collected 488 attributes (clinical data, biochemistry, and International Classification of Diseases, 10th Revision, diagnosis) in 1080 unique patients with CAT. We compared CAT-BLEED score, Ridge and Lasso logistic regression, random forest, and Extreme Gradient Boosting (XGBoost) algorithms for predicting major bleeding or clinically relevant nonmajor bleeding occurring 1 to 90 days, 1 to 365 days, and 90 to 455 days after venous thromboembolism (VTE).

RESULTS

The predictive performances of Lasso logistic regression, random forest, and XGBoost were higher than that of the CAT-BLEED score in the prediction of bleeding occurring 1 to 90 days and 1 to 365 days after VTE. For predicting major bleeding or clinically relevant nonmajor bleeding 1 to 90 days after VTE, the CAT-BLEED score achieved a mean area under the receiver operating characteristic curve (AUROC) of 0.48 ± 0.13, while Lasso logistic regression and XGBoost both achieved AUROCs of 0.64 ± 0.12. For predicting bleeding 1 to 365 days after VTE, the CAT-BLEED score achieved a mean AUROC of 0.47 ± 0.08, while Lasso logistic regression and XGBoost achieved AUROCs of 0.64 ± 0.08 and 0.59 ± 0.08, respectively.

CONCLUSION

This is the first machine learning-based risk model for bleeding prediction in patients with CAT receiving anticoagulation therapy. Its predictive performance was higher than that of the conventional CAT-BLEED score. With further development, this novel algorithm might enable clinicians to perform personalized anticoagulation strategies with improved clinical outcomes.

Symptoms and Impaired Quality of Life After COVID-19 Hospitalization: Effect of Therapeutic Heparin in Non-ICU Patients in the Accelerating COVID-19 Therapeutic Interventions and Vaccines 4 Acute Trial: Effect on 3-Month Symptoms and Quality of Life

BACKGROUND

Therapeutic-dose heparin decreased days requiring organ support in noncritically ill patients hospitalized for COVID-19, but its impact on persistent symptoms or quality of life (QOL) is unclear.

RESEARCH QUESTION

In the Accelerating COVID-19 Therapeutic Interventions and Vaccines 4 ACUTE (ACTIV-4a) trial, was randomization of patients hospitalized for COVID-19 illness to therapeutic-dose vs prophylactic heparin associated with fewer symptoms and better QOL at 90 days?

STUDY DESIGN AND METHODS

This was an open-label randomized controlled trial at 34 hospitals in the United States and Spain. A total of 727 noncritically ill patients hospitalized for COVID-19 from September 2020 to June 2021 were randomized to therapeutic-dose vs prophylactic heparin. Only patients with 90-day data on symptoms and QOL were analyzed. We ascertained symptoms and QOL by the EQ-5D-5L at 90-day follow-up in a preplanned analysis for the ACTIV-4a trial. Individual domains assessed by the EQ-5D-5L included mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Univariate and multivariate analyses were performed.

RESULTS

Among 571 patients, 288 (50.4%) reported at least one symptom. Among 410 patients, 148 (36.1%) reported moderate to severe impairment in one or more domains of the EQ-5D-5L. The presence of 90-day symptoms was associated with moderate-severe impairment in the EQ-5D-5L domains of mobility (adjusted OR [aOR], 2.37; 95% CI, 1.22-4.59), usual activities (aOR, 3.66; 95% CI, 1.75-7.65), pain (aOR, 2.43; 95% CI, 1.43-4.12), and anxiety (aOR, 4.32; 95% CI, 2.06-9.02), compared with patients reporting no symptoms There were no differences in symptoms or in the overall EQ-5D-5L index score between treatment groups. Therapeutic-dose heparin was associated with less moderate-severe impairment in all physical functioning domains (mobility, self-care, usual activities) but was independently significant only in the self-care domain (aOR, 0.32; 95% CI, 0.11-0.96).

INTERPRETATION

In a randomized controlled trial of hospitalized noncritically ill patients with COVID-19, therapeutic-dose heparin was associated with less severe impairment in the self-care domain of EQ-5D-5L. However, this type of impairment was uncommon, affecting 23 individuals.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov; No.: NCT04505774; URL: www.

CLINICALTRIALS

gov.

Safety and efficacy of direct oral anticoagulants in comparison to warfarin in obese patients with atrial fibrillation: A systematic review and meta-analysis

Background and Aim

Obesity affects nearly 650 million adults worldwide, and the prevalence is steadily rising. This condition has significant adverse effects on cardiovascular health, increasing the risk of hypertension, coronary artery disease, heart failure, and atrial fibrillation (AF). While anticoagulation for obese patients with AF is a well-established therapy for the prevention of thromboembolism, the safety and efficacy of different anticoagulants in this specific population are not well explored. This meta-analysis aimed to compare direct oral anticoagulants (DOAC) to vitamin K antagonists in obese populations with AF.

Methods

The PRISMA guidelines were followed for this meta-analysis, registered in PROSPERO (CRD42023392711). PubMed, PubMed Central, Embase, Cochrane Library, and Scopus databases were searched for relevant articles from inception through January 2023. Two independent authors screened titles and abstracts, followed by a full-text review in Covidence. Data were extracted in Microsoft Excel and analyzed using RevMan v5.4 using odds ratio as an effect measure.

Results

Two thousand two hundred fifty-nine studies were identified from the database search, and 18 were included in the analysis. There were statistically significant reductions in the odds of ischemic and hemorrhagic stroke in the DOAC group compared with the VKA group (OR 0.70, CI 0.66-0.75) and (OR 0.47, CI 0.35-0.62), respectively. In addition, the DOAC group exhibited lower odds of systemic embolism (OR 0.67, CI 0.54-0.83), major bleeding (OR 0.62, CI 0.54-0.72), and composite outcome (OR 0.72, CI 0.63-0.81).

Conclusion

Based on the findings from this meta-analysis, DOACs demonstrate superior safety and efficacy in obese patients with AF compared with VKAs. These results may have significant implications for guiding anticoagulation strategies in this patient population.

4-Factor Prothrombin Complex Concentrate Dosing Strategies: A Retrospective Evaluation

ObjectivesDetermine indication specific 4-Factor prothrombin complex concentrate (4FPCC) dosing strategies within a hospital system and subsequent effectiveness. Background: 4FPCC is FDA approved for reversal of vitamin K antagonists (VKA) for acute major bleeding or need for urgent surgery/invasive procedure. Since its approval, off label use has expanded to include direct oral anticoagulant reversal and perioperative hemostasis. Optimal dosing strategies remain controversial, and recent studies have evaluated fixed-dose regimens with lower doses than those recommended in product labeling. Methods/Materials: Retrospective cohort with manual chart review for patients who received 4FPCC spanning 2 years. Primary outcome was to characterize dosing. Secondary outcomes were INR normalization, hemostatic efficacy, in-hospital mortality, and renal function change. Results: Of the 300 patients evaluated, 80% received 4FPCC for anticoagulant reversal, with 66% of those for VKA and 34% for DOAC. The remaining 20% received 4FPCC for a non-reversal indication. Of the patients requiring anticoagulation reversal, 25% received doses lower than recommended and 6% received higher. 71% of patients received 4FPCC for life-threatening bleed, and 45% of them had intracranial hemorrhage. Higher mortality with higher than recommended doses was the only statistically significant secondary outcome (P = .018). Conclusion: We found that lower doses than recommended were used in a significant number of patients. The higher than recommended doses group constituted a small proportion of patients and the higher mortality was attributed to patient acuity on presentation. Additional studies evaluating dosing approach are required to determine lowest effective dosing for various indications.

Evaluation of enoxaparin for bridging of warfarin in outpatients with left ventricular assist devices (LVADs)

BACKGROUND

Patients with left ventricular assist devices (LVADs) require systemic anticoagulation. The use of enoxaparin for bridging to warfarin remains understudied in this population.

METHODS

This single-center retrospective study was performed to characterize enoxaparin use and associated thrombotic and bleeding outcomes in adult outpatients with LVADs from January 2018 to July 2021.

RESULTS

Fifty-four enoxaparin bridging events were evaluated in 49 patients. Most patients with HeartMate II (HM2) and HeartWare (HVAD) devices received enoxaparin dosed 1 mg/kg every 12 h. In patients with HeartMate 3 (HM3) devices, an equal number of patients received 0.5 mg/kg every 12 h and 1 mg/kg every 12 h, with a smaller subset receiving intermediate doses. The median duration of bridging was 6 days (4-8 [IQR]). One major bleeding event required discontinuation of enoxaparin and hospitalization in a patient with an HM3 device. Thrombotic events occurred in four patients with two incidents of pump thrombosis requiring pump exchange and two ischemic strokes. All thrombotic events occurred in patients with HVAD or HM2 devices.

CONCLUSION

These results suggest that enoxaparin bridging in LVAD patients was well-tolerated with low bleeding and thrombotic rates, particularly with the HM3 device.

Meta-Analysis Comparing Bivalirudin Versus. Unfractionated Heparin in Adult Patients With Extracorporeal Membrane Oxygenation

Introduction: Unfractionated heparin (UFH) has traditionally been the agent of choice in patients on extracorporeal membrane oxygenation (ECMO). However, direct thrombin inhibitors (DTI) have recently garnered more attention in ECMO because of their advantages over UFH. Given the heterogeneous results of multiple recent published studies, we performed a meta-analysis to describe pooled outcomes between bivalirudin and UFH anticoagulation in patients on ECMO. Methods: Relevant studies were identified from MEDLINE and Google Scholar database searches through April 23, 2022. The primary efficacy outcome was thromboembolism (TE), and secondary efficacy outcomes included all-cause mortality and circuit thrombosis. The primary safety outcome was major bleeding. Results: A total of 6 studies were included in the meta-analysis. Bivalirudin use was associated with significantly lower risk of TE (OR 0.61; 95% CI 0.38-.99; P = .05; I2 = 0%) and circuit thrombosis (OR 0.51; 95% CI .32-.80; P = .004; I2 = 0%) compared with UFH. There was no significant difference in all-cause mortality risk (OR 0.75; 95% CI .52-1.09; P = .13; I2 = 30%) between the bivalirudin and UFH groups. No significant difference in the risk of major bleeding between 2 groups was found (OR 0.67; 95% CI 0.25-1.81; P = .43; I2 = 80%). Conclusion: These data support that bivalirudin is a reasonable alternative to UFH in patients on ECMO. Randomized controlled trials are needed to confirm bivalirudin's efficacy and safety results compared with UFH.

Reduced-Dose Apixaban in the Treatment of Left Ventricular Thrombus: A Report of 2 Cases

According to the American College of Cardiology and the American Heart Association, warfarin has historically been the standard of care anticoagulant for the treatment of left ventricular thrombus. The use of direct oral anticoagulants (DOACs) has become more prevalent, as they require less frequent laboratory monitoring, offer fixed-dose regimens, are associated with fewer drug-drug and drug-food interactions, and provide more favorable safety profiles when compared to warfarin. However, DOACs are not currently FDA-indicated in the treatment of left ventricular (LV) thrombus. Numerous recent studies have reported and evaluated the use of DOACs for treatment of LV thrombus. Recently, a prospective, open-label, multicenter study evaluated warfarin compared to DOACs for LV thrombus treatment. The AHA recently published a scientific statement regarding the management of patients at risk for and with left ventricular thrombus, which included DOACs as a reasonable alternative to warfarin. This report describes two patients treated with DOACs following LV thrombus diagnosis. The first case is a 71-year-old male admitted for cerebrovascular accident and non-ST-elevation myocardial infarction complicated by a LV thrombus. The second case is an 83-year-old female admitted for acute myocardial infarction complicated with an LV thrombus. Both patients were prescribed apixaban 2.5 mg twice daily. Neither patient has experienced LV thrombus or DOAC treatment related complications. This case series serves as evidence for reduced-dose DOACs as an alternative to warfarin in the treatment of LV thrombus.

Outcomes of heparinized adult veno-arterial extracorporeal membrane oxygenation patients managed with low and high activated partial thromboplastin time targets: A systematic review and meta-analysis

INTRODUCTION

There are no randomized controlled trials comparing low and high activated partial thromboplastin time (aPTT) targets in heparinized adult veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) patients. Our systematic review and meta-analysis summarized complication rates in adult VA ECMO patients treated with low and high aPTT targets.

METHODS

Studies published from January 2000 to May 2022 were identified using Pubmed, Embase, Cochrane Library, and LILACS (Latin American and Caribbean Health Sciences Literature). Studies were included if aPTT was primarily used to guide heparin anticoagulation. For the low aPTT group, we included studies where aPTT goal was ≤60 seconds and for the high aPTT group, we included studies where aPTT goal was ≥60 seconds. Proportional meta-analysis with a random effects model was used to calculate pooled complication rates for patients in the two aPTT groups.

RESULTS

Twelve studies met inclusion criteria (5 in the low aPTT group and 7 in the high aPTT group). The pooled bleeding complication incidence for low aPTT studies was 53.6% (95% CI = 37.4%-69.4%, I2 = 60.8%) and for high aPTT studies was 43.8% (95% CI = 21.7%-67.1%, I2 = 91.8%). No studies in the low aPTT group reported overall thrombosis incidence, while three studies in the high aPTT group reported overall thrombosis incidence. The pooled thrombosis incidence for high aPTT studies was 16.1% (95% CI = 9.0%-24.5%, I2 = 13.1%).

CONCLUSIONS

Adult ECMO patients managed with low and high aPTT goals appeared to have similar bleeding and other complication rates further highlighting the need for a randomized controlled trial.

Epidemiology of anticoagulation for children supported by extracorporeal membrane oxygenation in the United States: A Pediatric Hospital Information System database study

INTRODUCTION

Due to the risk of thrombosis, nearly all children supported by extracorporeal membrane oxygenation (ECMO) receive systemic anticoagulation. While heparin has traditionally been used, there are reports of increased use of direct thrombin inhibitors. We sought to describe the use of anticoagulation in children supported by ECMO in the United States using a large administrative database.

METHODS

We performed a retrospective cohort study of children supported by ECMO within the Pediatric Health Information System (PHIS) database. Pediatric encounters involving ECMO from 2012 to 2020 were identified. Data regarding demographics, diagnoses, anticoagulation, complications, and outcomes were extracted for eligible encounters.

RESULTS

Eleven thousand five hundred ninety-five encounters that involved ECMO were identified. Fifty-four percent were male with an age range of 0-17 years and a median (IQR) age of 0 (0-2) years. Unfractionated heparin (UFH) only was used in 94% (95% CI: 93.6-94.5%) of encounters and UFH followed by bivalirudin in 5% (95% CI: 4.3-5.1%) of cases. There was a significant difference in the use of bivalirudin from 2012 to 2020 (p < 0.001). Differences in anticoagulation regimens were observed between infants and children (p = 0.004) and between those with and without cardiac indications for ECMO (p < 0.001). Four percent (95% CI: 4.1-4.8%) of encounters were associated with diagnostic coding for thrombosis and differences in occurrence of thrombosis were observed between different anticoagulant regimens (p < 0.001).

CONCLUSIONS

Though the majority of children on ECMO in the United States receive heparin anticoagulation, there is an increase in use of direct thrombin inhibitors. Prospective studies must evaluate the efficacy of different anticoagulants in this patient population.

Comparison of bleeding and thrombotic outcomes in veno-venous extracorporeal membrane oxygenation: Heparin versus bivalirudin

OBJECTIVES

We aimed to evaluate thrombotic and hemorrhagic complications with heparin versus bivalirudin use in veno-venous extracorporeal membrane oxygenation (V-V ECMO).

METHODS

We performed a retrospective cohort study of adult patients placed on V-V ECMO with intravenous anticoagulation with either heparin or bivalirudin. Time to thrombotic event and major bleed were analyzed in addition to related outcomes.

RESULTS

We identified 95 patients placed on V-V ECMO: 61 receiving heparin, 34 bivalirudin. The bivalirudin group had a higher rate of severe COVID-19, higher BMI, and longer ECMO duration. Despite this, bivalirudin was associated with reduced risk of thrombotic event (HR 0.14, 95% CI 0.06-0.32, p < .001) and increased average lifespan of the circuit membrane lung (16 vs. 10 days, p = 0.004). While there was no difference in major bleeding, the bivalirudin group required fewer transfusions of packed red blood cells and platelets per 100 ECMO days (means of 13 vs. 39, p = 0.004; 5 vs. 19, p = .014, respectively). Lastly, the bivalirudin group had improved survival to ECMO decannulation in univariate analysis (median OS 53 vs. 26 days, p = .015).

CONCLUSIONS

In this real-world analysis of bivalirudin versus heparin, bivalirudin is a viable option for V-V ECMO and associated with lower risk of thrombotic complications and fewer transfusion requirements.

Risk-based and individualised management of bleeding and thrombotic events in adults with primary immune thrombocytopenia (ITP)

Although bleeding is one of the main symptoms of primary immune thrombocytopenia (ITP), risk factors for bleeding have yet to be fully established. Low platelet count (PC; <20-30 × 109 /L) is generally indicative of increased risk of bleeding. However, PC and bleeding events cannot be fully correlated; many other patient- and disease-related factors are thought to contribute to increased bleeding risk. Furthermore, even though ITP patients have thrombocytopenia and are at increased risk of bleeding, ITP also carries higher risk of thrombotic events. Factors like older age and certain ITP treatments are associated with increased thrombotic risk. Women's health in ITP requires particular attention concerning haemorrhagic and thrombotic complications. Management of bleeding/thrombotic risk, and eventually antithrombotic therapies in ITP patients, should be based on individual risk profiles, using a tailored, patient-centric approach. Currently, evidence-based recommendations and validated tools are lacking to support decision-making and help clinicians weigh risk of bleeding against thrombosis. Moreover, evidence is lacking about optimal PC for achieving haemostasis in invasive procedures settings. Further research is needed to fully define risk factors for each event, enabling development of comprehensive risk stratification approaches. This review discusses risk-based and individualised management of bleeding and thrombosis risk in adults with primary ITP.

Intraoperative Bivalirudin Use in Patient Undergoing Femoral Endarterectomy with Heparin-Induced Thrombocytopenia: Case Report and Review of the Literature

PURPOSE

To describe the intraoperative use of bivalirudin during lower extremity revascularization in the setting of heparin-induced thrombocytopenia (HIT).

CASE SUMMARY

A 65 year-old man presented with left common iliac, external iliac, and femoral artery occlusion necessitating revascularization with left femoral endarterectomy and common and external iliac stent angioplasty. Three months before the femoral endarterectomy, the patient was hospitalized for a coronary artery bypass procedure. During this admission, the patient tested positive for the presence of heparin-PF4 antibody complexes. With the patient's recent history of HIT, bivalirudin was selected as the optimal agent for intraoperative anticoagulation. Bivalirudin was administered as a 50 mg bolus, followed by a continuous infusion initiated at 1.75 mg/kg/hr. Repeated bivalirudin boluses were necessary to maintain an activated clotting time (ACT) necessary for the revascularization procedures and recurrent subacute thrombi despite appropriate ACT values.

DISCUSSION

Bivalirudin has been utilized for cardiopulmonary bypass and carotid endarterectomy (CEA), but data for dosing in lower extremity revascularization are lacking. As the risk for thrombosis with HIT continues for months after diagnosis, it is important to elucidate optimal dosing of non-heparin anticoagulant options, such as the direct thrombin inhibitor, bivalirudin. The absence of validated dosing strategies for bivalirudin can result in prolonged operative times, increased risk of bleeding, and inadequate anticoagulation.

CONCLUSION

Bivalirudin is an appropriate agent for intraoperative anticoagulation in lower extremity revascularization. However, further investigation into the optimal intraoperative bivalirudin dosing regimen is necessary.

Clinical Outcomes and Predictors of Advanced Therapy for the Management of Right Heart Thrombus

BACKGROUND

The role of advanced therapies (systemic thrombolysis, catheter-based treatment, and surgical thrombectomy) for the management of right heart thrombus is poorly defined. In this study, we assessed the clinical predictors and outcomes of advanced therapy compared with anticoagulation alone for the acute management of right heart thrombus.

METHODS

In this observational cohort study, we analyzed consecutive patients who were treated for right heart thrombus. The primary end point was 90-day all-cause mortality. Clinical predictors of utilizing advanced therapy were assessed with multivariable logistic regression. Propensity score matching was utilized to compare adjusted outcomes between patients receiving advanced therapies versus anticoagulation alone.

RESULTS

A total of 345 patients were included in the study. Advanced therapy was utilized in 13.6% (N=47) of patients, of which 25.5% (N=12/47) was systemic thrombolysis, 23.4% (N=11/47) was endovascular thrombectomy, and 53.2% (N=25/47) was surgical thrombectomy. Younger age (odds ratio, 0.98 [95% CI, 0.96-0.99]) and concurrent pulmonary embolism (odds ratio, 5.36 [95% CI, 2.48-12.1]) predicted utilization of advanced therapy. In propensity score-matched analysis, there was no difference in 90-day mortality (hazard ratio, 0.46 [95% CI, 0.17-1.22]), in-hospital mortality (odds ratio, 0.64 [95% CI, 0.17-2.19]), or length of stay (β, -4.39 [95% CI, -14.0 to 5.22]) between advanced therapy and anticoagulation.

CONCLUSIONS

Among a diverse cohort of patients with right heart thrombus, outcomes did not differ between those who underwent advanced therapy and anticoagulation alone. Important predictors for utilizing advanced treatment included younger age and the presence of a concurrent pulmonary embolism. Future studies assessing advanced therapy in larger and broader patient populations are necessary.

Warfarin dosage in a postpartum woman while breastfeeding: A case report

Warfarin is the only oral anticoagulant recommended in women who are breastfeeding. Although warfarin is a compatible and recommended agent in the postpartum period and during lactation, little is known regarding changes to warfarin dose requirements in this patient population. Here, we report the case of a 40-year-old woman who transitioned from enoxaparin monotherapy back to warfarin at 2 months postpartum, while she was breastfeeding. Despite resuming warfarin at her previously therapeutic dose, her international normalized ratio (INR) remained subtherapeutic and required multiple dose increases. She ultimately required a 100% increase in her warfarin dose postpartum, compared to pre-pregnancy, to achieve a therapeutic INR. This case suggests patients may require higher warfarin doses postpartum, compared to pre-pregnancy, especially if breastfeeding. Clinicians should closely monitor these patients and adjust warfarin doses as necessary.

Finding a common definition of heparin resistance in adult cardiac surgery: communication from the ISTH SSC subcommittee on perioperative and critical care thrombosis and hemostasis

Ensuring adequate anticoagulation for patients requiring cardiac surgery and cardiopulmonary bypass (CPB) is important due to the adverse consequences of inadequate anticoagulation with respect to bleeding and thrombosis. When target anticoagulation is not achieved with typical doses, the term heparin resistance is routinely used despite the lack of uniform diagnostic criteria. Prior reports and guidance documents that define heparin resistance in patients requiring CPB and guidance documents remain variable based on the lack of standardized criteria. As a result, we conducted a review of clinical trials and reports to evaluate the various heparin resistance definitions employed in this clinical setting and to identify potential standards for future clinical trials and clinical management. In addition, we also aimed to characterize the differences in the reported incidence of heparin resistance in the adult cardiac surgical literature based on the variability of both target-activated clotting (ACT) values and unfractionated heparin doses. Our findings suggest that the most extensively reported ACT target for CPB is 480 seconds or higher. Although most publications define heparin resistance as a failure to achieve this target after a weight-based dose of either 400 U/kg or 500 U/kg of heparin, a standardized definition would be useful to guide future clinical trials and help improve clinical management. We propose the inability to obtain an ACT target for CPB of 480 seconds or more after 500 U/kg as a standardized definition for heparin resistance in this setting.

Postoperative anticoagulation management using subcutaneous unfractionated heparin for a patient with nonbacterial thrombotic endocarditis: a case report

Nonbacterial thrombotic endocarditis (NBTE) presents nonbacterial vegetation on cardiac valves. NBTE requires appropriate anticoagulant therapy to prevent recurrence after surgery. However, there has not yet been established evidence for anticoagulant therapy in NBTE, and low molecular weight heparin is not approved in Japan. We present a case of NBTE that was successfully managed with anticoagulant therapy using subcutaneous unfractionated heparin. A 59-year-old woman was diagnosed with NBTE on the mitral and tricuspid valve associated with breast cancer, underwent valve replacement. Warfarin and continuous intravenous unfractionated heparin were started. However, disseminated intravascular coagulation occurred after heparin was discontinued. Continuous intravenous unfractionated heparin injection was resumed immediately, and subcutaneous unfractionated heparin was administered before discharge. Postoperative echocardiography revealed no vegetation on the prosthetic valves thereafter. Subcutaneous unfractionated heparin therapy is useful to prevent the recurrence of NBTE as the anticoagulation in outpatients.

Apixaban-Associated Intracranial Hemorrhage in a Patient With Elevated International Normalized Ratio

Apixaban has been associated with prolongation of the international normalized ratio (INR), but data surrounding the extent of elevation and its clinical significance are limited. Due to interaction between apixaban and the prothrombin assay, elevations in INR in patients receiving apixaban are common and not always grounds for concern. However, in high risk patients, elevations can represent a need for closer monitoring. This case summarizes an 82-year-old woman with a history of atrial fibrillation and left middle cerebral artery strokes with no residual deficits. She presented with right-sided hemiparesis and aphasia and underwent a mechanical thrombectomy with TICI 2b recanalization of a left M1 occlusion. Post-thrombectomy, she was found to have a left atrial thrombus and 10 days later was started on apixaban 5 mg twice daily. On the fourth day of apixaban therapy, she experienced an INR increase to 2.3, prompting initiation of a vitamin K challenge for nutritional deficiency. Despite initial improvement, her INR increased to 2.7 a week after apixaban was initiated, coinciding with a decline in mental status and an apixaban peak level of 435.6 ng/mL (reference range 91-321 ng/mL). A computed tomography (CT) scan of her head showed new intracranial hemorrhage in the area of her previous infarction, prompting apixaban reversal with andexanet alfa. Unfortunately, the patient expired. This case report highlights the importance and difficulty in performing therapeutic drug monitoring in patients receiving oral anti-factor Xa inhibitors, revealing a downside to administration of high-risk medications that do not have readily available monitoring.

Anti-factor Xa as the preferred assay to monitor heparin for the treatment of pulmonary embolism

INTRODUCTION

The mainstay of acute pulmonary embolism (PE) treatment is anticoagulation. Timely anticoagulation correlates with decreased PE-associated mortality, but the ability to achieve a therapeutic activated partial thromboplastin time (aPTT) with unfractionated heparin (UFH) remains limited. Although some institutions have switched to a more accurate and reproducible test to assess for heparin's effectiveness, the anti-factor Xa (antiXa) assay, data correlating a timely therapeutic antiXa to PE-associated clinical outcomes remains scarce. We evaluated time to a therapeutic antiXa using intravenous heparin after PE response team (PERT) activation and assessed clinical outcomes including bleeding and recurrent thromboembolic events.

METHODS

This was a retrospective cohort study at NYU Langone Health. All adult patients ≥18 years with a confirmed PE started on IV UFH with >2 antiXa levels were included. Patients were excluded if they received thrombolysis or alternative anticoagulation. The primary endpoint was the time to a therapeutic antiXa level of 0.3-0.7 units/mL. Secondary outcomes included recurrent thromboembolism, bleeding and PE-associated mortality within 3 months.

RESULTS

A total of 330 patients with a PERT consult were identified with 192 patients included. The majority of PEs were classified as sub massive (64.6%) with 87% of patients receiving a bolus of 80 units/kg of UFH prior to starting an infusion at 18 units/kg/hour. The median time to the first therapeutic antiXa was 9.13 hours with 93% of the cohort sustaining therapeutic anticoagulation at 48 hours. Recurrent thromboembolism, bleeding and mortality occurred in 1%, 5% and 6.2%, respectively. Upon univariate analysis, a first antiXa <0.3 units/ml was associated with an increased risk of mortality [27.78% (5/18) vs 8.05% (14/174), p = 0.021].

CONCLUSION

We observed a low incidence of recurrent thromboembolism or PE-associated mortality utilizing an antiXa titrated UFH protocol. The use of an antiXa based heparin assay to guide heparin dosing and monitoring allows for timely and sustained therapeutic anticoagulation for treatment of PE.

Challenges in ageing persons with haemophilia

As treatments for individuals with inherited bleeding disorders improve, life expectancy increases and is approaching that of the normal population. Concomitant with this we are now seeing the problems of ageing in the bleeding disorder population. Although the clear-cut association between low clotting factor levels and risk of bleeding is well recognised, a relationship between high levels, some non-factor therapies and thrombotic risk also exists. The management of thrombosis in persons with inherited bleeding disorders is complex but manageable with modern treatments and collaboration in decision making between health care professionals and patients. Despite the improvements in treatment and reduction in bleeding, mostly musculoskeletal pain continues to be a major issue with advancing age. The management of pain amongst older people with haemophilia who may have multiple comorbidities should involve a person-centred, holistic, multi-disciplinary approach to support and optimise long-term physical functioning and overall quality of life.

Pylephlebitis combined with septic shock secondary to acute nonperforated appendicitis: a case report

Pylephlebitis, which is a type of septic thrombophlebitis of the portal vein, is a rare and life-threatening complication that commonly occurs following appendicitis. However, nonspecific abdominal complaints and fever can impede the diagnosis of pylephlebitis. Timely use of appropriate antibiotics and anticoagulants is paramount for treating this condition. We present a case of pylephlebitis and septic shock caused by acute nonperforated appendicitis. A 32-year-old man presented with migratory right lower abdominal pain. Blood cultures showed the presence of Escherichia coli. Blood test results showed increased bilirubin concentrations and coagulation factor abnormalities. A computed tomographic abdominal scan showed that the portal vein had a widened intrinsic diameter. After intensive care treatment with antibiotics, antishock therapy, anticoagulants, and other supportive treatments, the infection was monitored, the abdominal pain disappeared, and the jaundice subsided. Laparoscopic appendectomy was performed. Histopathology showed acute suppurative appendicitis, and no abnormalities were observed during the follow-up period after discharge. A multidisciplinary approach is mandatory for the decision-making process in the presence of pylephlebitis caused by appendicitis to obtain a correct diagnosis and prompt treatment. Similarly, the timing of appendectomy is important for minimizing intra- and postoperative complications.

Association of Argatroban Dose With Coagulation Laboratory Test in Patients on Extracorporeal Membrane Oxygenation: Activated Clotting Time vs Activated Partial Thromboplastin Time

BACKGROUND

Only some studies have directly compared and analyzed the roles of activated partial thromboplastin time (aPTT) and activated clotting time (ACT) in coagulation monitoring during argatroban administration.

OBJECTIVES

This study aims to assess the correlation of argatroban dose with ACT and aPTT values and to identify the optimal coagulation test for argatroban dose adjustment.

METHODS

We evaluated 55 patients on extracorporeal membrane oxygenation (ECMO) who received argatroban for more than 72 hours. The correlation between argatroban dose and aPTT and ACT values was evaluated. To compare argatroban dose and bleeding events according to liver dysfunction, the patients were divided into 2 groups based on alanine aminotransferase and total bilirubin.

RESULTS

Among the 55 patients, a total of 459 doses and coagulation tests were evaluated. The aPTT and ACT values showed a weak correlation with argatroban dose, with the Pearson correlation coefficients of 0.261 (P < 0.001) and 0.194 (P = 0.001), respectively. The agreement between the target 150 to 180 seconds for ACT and 55 to 75 seconds for aPTT was observed in 140 patients (46.1%). Twenty-four patients (43.6%) had liver dysfunction when they started argatroban. The median argatroban dose was lower in the liver dysfunction group than in the control group (0.094 mcg/kg/min vs 0.169 mcg/kg/min, P = 0.020). Difference was not observed between the 2 groups in the amount of red blood cell (0.47 vs 0.43 pack, P = 0.909) and platelet (0.60 vs 0.08 pack, P = 0.079) transfusion per day.

CONCLUSION AND RELEVANCE

A weak correlation was observed between argatroban dose and the aPTT and ACT values. However, the agreement between aPTT and ACT was only 46.1% regarding the scope of target range. Further research is necessary to determine how to assess the optimal argatroban dose for patients administered argatroban while undergoing ECMO at the intensive care unit.

Management of Acute Lower Limb Ischemia Without Surgical Revascularization - A Population-Based Study

OBJECTIVES

To evaluate outcomes of management without surgical revascularization in patients with acute lower limb ischemia (ALI) in a population-based setting.

DESIGN

Retrospective observational population-based study.

MATERIALS

Patients from Malmö, Sweden, hospitalized for ALI between 2015 and 2018.

METHODS

In-hospital, surgical, radiological, and autopsy registries were scrutinized for descriptive data on ALI patients managed by endovascular and open vascular surgery, conservative vascular therapy, primary major amputation, and palliative care.

RESULTS

Among 161 patients, 73 (45.3%) did not undergo any operative revascularization. Conservative vascular therapy, primary amputation, and palliative care were conducted in 25 (15.5%), 26 (16.1%), and 22 (13.7%) patients, respectively. Conservatively treated patients had Rutherford class ≥ IIb ischemia and embolic occlusion in 33% and 68% of cases, respectively. Their median C-reactive protein level at admission was 7 mg/L (interquartile range 2 - 31 mg/L). Among conservatively treated patients, anticoagulation therapy in half to full dose was given to 22 (88%) patients for six weeks or longer, and analgesics in low or moderate doses were given to twelve (48%) patients at discharge. The major amputation rate at 1 year was 8% among conservatively treated patients, and four patients with foot embolization had not undergone amputation at 1 year.

CONCLUSION

Patients selected for initial conservative therapy of ALI with anticoagulation alone may have a good outcome, even when admitted with Rutherford class IIb ischemia. A low C-reactive protein level at admission seems to be a favorable marker when choosing conservative therapy. A prospective, preferably multicenter, study with a predefined protocol in these conservatively treated patients is warranted to better define the dose and length of anticoagulation therapy.

Epidemiology, prognosis, and challenges in the management of hyperthyroidism-related atrial fibrillation

Atrial fibrillation (AF) is a common condition with a global estimated prevalence of 60 million cases, and the most common cardiac complication of hyperthyroidism, occurring in 5-15% of overtly hyperthyroid patients. Additionally, subclinical hyperthyroidism and high-normal free T4 have been associated with an increased risk in the development of AF. Hyperthyroidism-related AF is a reversible cause of AF, and the majority of patients spontaneously revert to sinus rhythm in 4-6 months during or after restoration of euthyroidism. Therefore, restoring thyroid function is an indispensable element in hyperthyroidism-related AF management. Rate control with beta-blockers consists another first-line therapy, reserving rhythm control in cases of persistent hyperthyroidism-related AF. It is still controversial whether hyperthyroidism is an independent risk factor of stroke in nonvalvular AF. As a result, initiating anticoagulation should be guided by the clinical thromboembolic risk score CHA2DS2-VASc score in the same way it is applied in patients with non-hyperthyroidism-related AF. Treatment with the novel direct oral anticoagulants appears to be as beneficial and may be safer than warfarin in patients with hyperthyroidism-related AF. In this review, we address the epidemiology, prognosis, and diagnosis of hyperthyroidism-related AF, and we discuss the management strategies and controversies in patients with hyperthyroidism-related AF.

Assessment of Population-Based Approach to Direct Oral Anticoagulant Management

Background: As preferences for oral anticoagulation shift from warfarin to direct oral anticoagulants (DOACs), a new care management model is needed. A population approach leveraging a DOAC Dashboard was implemented to track all patients on a DOAC followed by a physician at an academic medical center. The DOAC Dashboard is a real-time report within the electronic health record (EHR) that identifies patients who require evaluation for DOAC dose/therapy adjustment due to changing renal function, age, weight, indication, and/or significant drug-drug interaction (DDI). Objective: This study aims to describe the initial phase of DOAC Dashboard implementation, to evaluate the effectiveness of interventions, and to assess a multidisciplinary approach to management. Method: Retrospective descriptive study of the DOAC Dashboard from August 22, 2019, to January 20, 2022. Primary outcomes include total number of alerts addressed and interventions needed. Secondary outcome is the proportion of interventions implemented by the prescribing clinician. Result: A total of 10 912 patients were identified by the DOAC Dashboard at baseline. A total of 5038 alerts were identified, with 668 critical alerts, 3337 possible critical alerts, and 1033 other alerts. Pharmacists addressed 1796 alerts during the study period (762 critical alerts and 1034 possible critical). Critical alerts included 62 significant DDI, 379 inappropriate dosing, and 321 others. Of the critical alerts, intervention was needed in 291 cases (38%), with 255 (88%) of proposed interventions implemented. Critical alerts and possible critical alerts not requiring intervention were resolved by data entry. Conclusion: The DOAC Dashboard provides an efficient method of identifying patients on DOACs that require dose adjustments or therapeutic modifications.

European practices on antithrombotic management during percutaneous mechanical circulatory support in adults: A survey of the Association for Acute CardioVascular Care (ACVC) of the ESC and the European branch of the Extracorporeal Life Support Organization (EuroELSO)

BACKGROUND

Bleeding and thrombotic complications compromise outcomes in patients undergoing percutaneous mechanical circulatory support (pMCS) with veno-arterial extracorporeal membrane oxygenation (V-A ECMO) and/or microaxial flow pumps like the Impella™. Antithrombotic practices are an important determinant of the coagulopathic risk, but standardization in the antithrombotic management during pMCS is lacking. This survey outlines European practices in antithrombotic management in adults on pMCS, making an initial effort to standardize practices, inform future trials, and enhance outcomes.

METHODS

This online cross-sectional survey was distributed through digital newsletters and social media platforms by the Association of Acute Cardiovascular Care and the European branch of the Extracorporeal Life Support Organization. The survey was available from April 17th to May 23rd, 2023. The target population were European clinicians involved in care for adults on pMCS.

RESULTS

We included 105 responses from 26 European countries. Notably, 72.4% of the respondents adhered to locally established anticoagulation protocols, with unfractionated heparin (UFH) being the predominant anticoagulant (Impella™: 97.0% and V-A ECMO: 96.1%). A minority, 10.8% and 14.5%, respectively, utilized anti-factor-Xa assay with activated partial thromboplastin time in parallel for UFH monitoring during Impella™ and V-A ECMO support. Anticoagulant targets varied across institutions. Following acute coronary syndrome without percutaneous coronary intervention (PCI), 54.0% and 42.7% administered dual antiplatelet therapy during Impella™ and V-A ECMO support, increasing to 93.7% and 84.0% after PCI.

CONCLUSIONS

Substantial heterogeneity in antithrombotic practices emerged from participants' responses, potentially contributing to variable device-associated bleeding and thrombotic complications.

Prophylactic Anticoagulation and Thrombosis in Hospitalized Patients with Clinically Stable COVID-19 at Admission: From the Practice-Based Observational Study

Objectives: The potential benefit of routine prophylactic anticoagulation for all hospitalized patients with clinically stable coronavirus disease 2019 (COVID-19) is still controversial. Method: The CLOT-COVID Study was a multicenter observational study enrolling 2894 consecutive hospitalized patients with COVID-19. The current study population consisted of 1738 hospitalized patients with mild COVID-19 at admission not requiring oxygen administration, who were divided into 2 groups: patients with prophylactic anticoagulation (n = 326) and those without (n = 1412). Results: Patients with prophylactic anticoagulation had more severe status of the worst severity of COVID-19 during hospitalization compared with those without (mild: 38% versus 82%, moderate: 55% versus 17%, and severe or death at discharge: 6.4% versus 0.7%, P <0.001). During hospitalization, 8 patients (0.5%) developed thrombosis, and the incidences of thrombosis were numerically higher in patients with more severe status of worst severity of COVID-19 during hospitalization (mild: 0.2%, moderate: 1.2%, and severe or death at discharge: 3.2%). Conclusions: Among hospitalized patients with clinically stable COVID-19 at admission, patients who did not worsen in COVID-19 severity after admission rarely developed thrombosis, although patients with worsening of COVID-19 severity after admission more often received prophylactic anticoagulation and might have a higher risk of thrombosis.

Biomimetic Anticoagulated Porous Particles with Self-Reporting Structural Colors

Anticoagulation is vital to maintain blood fluidic status and physiological functions in the field of clinical blood-related procedures. Here, novel biomimetic anticoagulated porous inverse opal hydrogel particles is presented as anticoagulant bearing dynamic screening capability. The inverse opal hydrogel particles possess abundant sulfonic and carboxyl groups, which serve as binding sites with multiple coagulation factors and inhibit the blood coagulation process. Owing to the variations of refractive index and pore sizes during the binding process, the particles appeared corresponding structure color variations, which can be adopted as sensory index of anticoagulation. Based on these features, a sensor containing these diverse structure color particle units is constructed for pattern recognition of coagulation factors level in clinical plasma samples. By analyzing the sensory information of the unit, the colorimetric "fingerprint" for each target can be obtained and summarized as a database. Besides, a portable test-strip integrating sensory units is developed to distinguish the sample regarding abnormal coagulation factors-derived diseases via multivariate data analysis. It is believed that such biomimetic anticoagulated structural color particles and their derived sensor will open new avenue for clinical detection and disease diagnosis.

Anaesthesiologic Considerations for Intraoperative ECMO Anticoagulation During Lung Transplantation: A Single-Centre, Retrospective, Observational Study

Background: Extracorporeal membrane oxygenation (ECMO) is frequently used during lung transplantation. Unfractionated heparin (UFH) is mainly used as part of ECMO support for anticoagulation. One of the most common perioperative complications is bleeding, which high-dose UFH can aggravate. Methods: We retrospectively analyzed (n = 141) patients who underwent lung transplantation between 2020 and 2022. All subjects (n = 109) underwent central cannulated VA ECMO with successful intraoperative ECMO weaning. Patients on ECMO bridge, postoperative ECMO, heart-lung transplants and transplants without ECMO were excluded. The dose of UFH for the entire surgical procedure, blood loss and consumption of blood derivatives intraoperatively and 48 h after ICU admission were recorded. Surgical revision for postoperative bleeding were analyzed. Thrombotic complications, mortality and long-term survival were evaluated. Results: Lower doses of UFH administered for intraoperative ECMO anticoagulation contribute to a reduction in intraoperative blood derivates consumption and blood loss with no thrombotic complications related to the patient or the ECMO circuit. Lower doses of UFH may lead to a decreased incidence of surgical revision for hemothorax. Conclusion: Lower doses of UFH as part of intraoperative ECMO anticoagulation might reduce the incidence of complications and lead to better postoperative outcomes.

Efficacy and Safety of Non-Vitamin-K Antagonist Oral Anticoagulants Versus Warfarin Across the Spectrum of Body Mass Index and Body Weight: An Individual Patient Data Meta-Analysis of 4 Randomized Clinical Trials of Patients With Atrial Fibrillation

BACKGROUND

The efficacy and safety of non-vitamin-K antagonist oral anticoagulants (NOACs) across the spectrum of body mass index (BMI) and body weight (BW) remain uncertain.

METHODS

We analyzed data from COMBINE AF (A Collaboration Between Multiple Institutions to Better Investigate Non-Vitamin K Antagonist Oral Anticoagulant Use in Atrial Fibrillation), which pooled patient-level data from the 4 pivotal randomized trials of NOAC versus warfarin in patients with atrial fibrillation. The primary efficacy and safety outcomes were stroke or systemic embolic events (stroke/SEE) and major bleeding, respectively; secondary outcomes were ischemic stroke/SEE, intracranial hemorrhage, death, and the net clinical outcome (stroke/SEE, major bleeding, or death). Each outcome was examined across BMI and BW. Because few patients had a BMI <18.5 kg/m2 (n=598), the primary analyses were restricted to those with a BMI ≥18.5 kg/m2.

RESULTS

Among 58 464 patients, the median BMI was 28.3 (interquartile range, 25.2-32.2) kg/m2, and the median BW was 81.0 (interquartile range, 70.0-94.3) kg. The event probability of stroke/SEE was lower at a higher BMI irrespective of treatment, whereas the probability of major bleeding was lower at a higher BMI with warfarin but relatively unchanged across BMI with NOACs. NOACs reduced stroke/SEE overall (adjusted hazard ratio [HRadj], 0.80 [95% CI, 0.73-0.88]; P<0.001), with a generally consistent effect across BMI (Ptrend across HRs, 0.48). NOACs also reduced major bleeding overall (HRadj, 0.88 [95% CI, 0.82-0.94]; P<0.001), but with attenuation of the benefit at a higher BMI (trend test across BMI [Ptrend], 0.003). The overall treatment effects of NOACs versus warfarin for secondary outcomes were consistent across BMI, with the exception of the net clinical outcome and death. While these outcomes were overall reduced with NOACs (net clinical outcome, HRadj, 0.91 [95% CI, 0.87-0.95]; P<0.001; death, HRadj, 0.91 [95% CI, 0.86-0.97]; P=0.003), these benefits were attenuated at higher BMI (Ptrend, 0.001 and 0.08, respectively). All findings were qualitatively similar when analyzed across BW.

CONCLUSIONS

The treatment effect of NOACs versus warfarin in atrial fibrillation is generally consistent for stroke/SEE across the spectrum of BMI and BW, whereas the reduction in major bleeding is attenuated in those with higher BMI or BW. Death and the net clinical outcome are overall reduced with NOACs over warfarin, although there remain uncertainties for these outcomes at a very high BMI and BW.