Rivaroxaban with or without Aspirin in Stable Cardiovascular Disease

External applicability of the COMPASS trial: the Western Denmark Heart Registry

Aims

In the COMPASS trial, combined aspirin and rivaroxaban treatment reduced ischaemic events in patients with stable coronary artery disease (CAD) or peripheral artery disease (PAD). We estimated the proportion of COMPASS eligible patients among unselected patients undergoing coronary angiography (CAG) and compared outcome rates among COMPASS eligible and non-eligible patients.

Methods and results

We applied the COMPASS study criteria on patients undergoing CAG in Western Denmark (2004–11). Both COMPASS eligible and non-eligible patients had CAD/PAD and met no exclusion criteria, but only COMPASS eligible patients met the inclusion criteria. We assessed the COMPASS primary endpoint of cardiovascular death, ischaemic stroke, haemorrhagic stroke, or myocardial infarction (MI). We computed event rates and adjusted incidence rate ratios (aIRRs). Of 80 071 patients undergoing CAG, 27 939 did not have CAD or PAD and were not considered. Of the 52 132 patients remaining, 11 930 were COMPASS eligible. Rates of the primary endpoint were 4.8 (95% confidence interval 4.6–5.0) events per 100 person-years among COMPASS eligible patients and 2.3 (2.2–2.4) among COMPASS non-eligible patients [aIRR 1.7 (1.6–1.9)]. COMPASS eligible patients also had higher risks of cardiovascular death [aIRR 2.5 (2.1–3.0)], ischaemic stroke [aIRR 1.4 (1.2–1.6)], and MI [aIRR 1.9 (1.7–2.1)].

Conclusion

In this all-comers CAG cohort, 15% were eligible for combined aspirin and rivaroxaban treatment. COMPASS eligible patients had up to 2.5-fold higher rates of cardiovascular events than non-eligible patients. The higher incidence of ischaemic events in COMPASS eligible patients highlights an unmet need for additional preventive measures.

Safety and Efficacy of Rivaroxaban When Added to Aspirin Monotherapy Among Stabilized Post‐Acute Coronary Syndrome Patients: A Pooled Analysis Study of ATLAS ACS‐TIMI 46 and ATLAS ACS 2‐TIMI 51

Background

A residual risk of ischemic events following an acute coronary syndrome (ACS) remains despite antiplatelet therapy. The addition of an antithrombin as part of a “dual pathway” approach may further improve outcomes as thrombin generation persists for several months post‐ACS. The present study evaluates the safety and efficacy of “dual pathway” therapy (rivaroxaban plus aspirin) as compared with aspirin monotherapy among post‐ACS patients.

Methods and Results

A total of 1477 patients were analyzed in a pooled analysis of subsets of the ATLAS ACS‐TIMI (Anti‐Xa Therapy to Lower cardiovascular events in addition to Aspirin with or without thienopyridine therapy in Subjects with Acute Coronary Syndrome – Thrombolysis in Myocardial Infarction) 46 and ATLAS ACS 2‐TIMI 51 trials including post‐ACS patients receiving aspirin monotherapy and randomized to either rivaroxaban 2.5 mg BID or rivaroxaban 5 mg BID or placebo. The primary efficacy end point was a composite of cardiovascular death, myocardial infarction (MI), or stroke (ischemic, hemorrhagic, or of uncertain cause). The primary safety end point was TIMI‐non‐coronary artery bypass (CABG) major bleeding. The combined rivaroxaban group (2.5 or 5 mg BID) among stabilized post‐ACS patients on a background of aspirin monotherapy was associated with a significant reduction in the primary end point as compared with placebo (hazard ratio=0.65, 95% CI=0.45–0.92, P=0.016). Although the combined rivaroxaban dose groups were associated with higher rates of non‐CABG TIMI major bleeding, the 2.5 mg dose group was not, and the overall number of patients experiencing a non‐CABG TIMI major bleeding event was low (1.5%).

Conclusions

Among patients in the immediate post‐ACS period, a “dual pathway” approach using aspirin and low‐dose rivaroxaban may reduce the risk of secondary atherothrombotic events, but increase bleeding risk.

Clinical Trial Registration

URL: https://www.clinicaltrials.gov. Unique identifiers: NCT00402597; NCT00809965.

See Editorial by Harrison and Newby

Technical improvements in carotid revascularization based on the mechanism of procedural stroke

The benefit of carotid revascularization in patients with severe carotid artery stenosis is hampered by the risk of stroke due to the intervention itself. The risk of periprocedural strokes is higher for carotid artery stenting (CAS) as compared to carotid endarterectomy (CEA). Over the past years, the pathophysiological mechanism responsible for periprocedural stroke seems to unfold step by step. Initially, all procedural strokes were thought to be the result of technical errors during surgical repair: cerebral ischemia due to clamping time of the carotid artery, cerebral embolization of atherosclerotic debris due to manipulation of the atheroma or thrombosis of the artery. Following improvements in surgical techniques, technical skills, new intraoperative monitoring technologies such as angioscopy, and the results of the first large clinical randomized controlled trials (RCT) it was believed that most periprocedural strokes were of thromboembolic nature, while a large part of these caused by technical error. Nowadays, analyses of underlying pathophysiological mechanisms of procedural stroke make a clinically relevant distinction between intra-procedural and postprocedural strokes. Intra-procedural stroke is defined as hypoperfusion due to clamping (CEA) or dilatation (CAS) and embolization from the carotid plaque (both CEA and CAS). Postprocedural stroke can be caused by thrombo-embolisation but seems to have a primarily hemodynamic origin. Besides thrombotic occlusion of the carotid artery, cerebral hyperperfusion syndrome (CHS) due to extensively increased cerebral revascularization is the most reported pathophysiological mechanism of postprocedural stroke. Multiple technical improvements have attempted to lower the risk of periprocedural stroke. The introduction of antiplatelet therapy (APT) has significantly reduced the risk of thromboembolic events in patients with carotid stenosis. Over the years, recommendations regarding APT changed. While for a long time APT was discontinued prior to surgery because of a fear of increased bleeding risk, nowadays continuation of APT during carotid intervention (aspirin monotherapy or even dual APT including clopidogrel) is found to be safe and effective. In CAS patients, dual APT up to three months' postprocedural is considered best. Stent design and cerebral protection devices (CPD) for CAS procedure are continuously under development. Trials have suggested a benefit of closed-cell stent design over open-cell stent design in order to reduce procedural stroke, while the benefit of CPD during stenting is still a matter of debate. Although CPD reduce the risk of procedural stroke, a higher number of new ischemic brain lesions detected on diffusion weighted imaging was found in patients treated with CPD. In patients undergoing CEA under general anesthesia, adequate use of cerebral monitoring (EEG and transcranial Doppler [TCD]) has reduced the number of intraoperative stroke by detecting embolization and thereby guiding the surgeon to adjust his technique or to selectively shunt the carotid artery. In addition, TCD is able to adequately identify and exclude patients at risk for CHS. For CAS, the additional value of periprocedural cerebral monitoring to prevent strokes needs urgent attention. In conclusion, this review provides an overview of the pathophysiological mechanism of stroke following carotid revascularization (both CAS and CEA) and of the technical improvements that have contributed to reducing this stroke risk.

Comorbidities in clinical practice. Algorithms for diagnostics and treatment

.

Prognostic impact of residual stenosis after percutaneous coronary intervention in patients with ischemic heart failure - A report from the CHART-2 study

BACKGROUND

Complete revascularization with PCI is not always achieved in patients with ischemic HF. Therefore, this study aimed to elucidate the prognostic impact of residual coronary stenosis (RS) after percutaneous coronary intervention (PCI) in patients with ischemic heart failure (HF).

METHODS

We analyzed a total of 1307 patients with symptomatic HF and a history of PCI registered in our Chronic Heart Failure Analysis and Registry in the Tohoku District-2 (CHART-2) Study. RS that was defined as the presence of ≥70% luminal stenosis in major coronary arteries at the last coronary angiography.

RESULTS

Among the study population, 851 patients (65.1%) had RS. During a median follow-up period of 3.2 years, patients with RS had higher all-cause mortality than those without it even after propensity score matching (21.9 vs. 11.6%, log-rank P = 0.027). Multivariable Cox hazard analysis also showed the negative impact of RS on all-cause death in ischemic HF patients [hazard ratio (HR):1.62, 95% confidence interval (CI): 1.07-2.46, P = 0.024]. Importantly, when divided all subjects into three subgroups by left ventricular ejection fraction (LVEF) [LVEF < 40% (HFrEF), LVEF 40-49% (HFmrEF), and LVEF ≥ 50% (HFpEF)], inverse probability of treatment weighted method provided a similar result that RS after PCI was an independent risk factor for death in the HFpEF [HR(95%CI); 1.94(1.22-3.09), P < 0.01] and HFmrEF [4.47(1.13-14.98), P < 0.01] groups, but not in the HFrEF group [1.20(0.59-2.43), P = 0.62].

CONCLUSIONS

These results indicate that RS after PCI could aggravate long-term prognosis of ischemic HF patients with moderate- to well-preserved EF, but not those with reduced EF.

Antithrombotics in stable peripheral artery disease

Patients with peripheral artery disease (PAD) are at high risk for ischemic cardiovascular complications. While single antiplatelet therapy (SAPT), predominantly aspirin, has long been the standard antithrombotic treatment in stable PAD, there have now been greater than 40,000 PAD patients randomized to varying antiplatelet and/or anticoagulant regimens. In this review, we provide a summary of the current evidence for antithrombotics in stable PAD, focusing on the rates of major adverse cardiovascular events (MACE), major adverse limb events (MALE), and major bleeding. SAPT has a limited role in the treatment of asymptomatic PAD, particularly in the absence of concomitant coronary artery disease. In symptomatic PAD, SAPT is effective in preventing MACE, though treatment with a thienopyridine appears marginally superior to aspirin. Dual antiplatelet therapy (DAPT) suggests benefit over SAPT in reducing MACE and MALE, though studies to date are not conclusive and/or are associated with excess major bleeding. Combining moderate to high intensity vitamin K antagonists with antiplatelet therapy does not reduce MACE or MALE and increases life-threatening bleeding. Rivaroxaban 2.5 mg BID in addition to aspirin reduces the incidence of both MACE and MALE as compared to aspirin alone, without increasing life-threatening bleeding. This regimen is associated with a reduced severity of MALE when it does occur. Comparisons across antithrombotic trials in PAD are challenging given the heterogeneity of patient populations and the differing assessment of outcomes. The vascular medicine practitioner can reduce ischemic cardiac and limb events, as well as minimize life-threatening bleeding, by choosing the optimal antithrombotic regimen in their PAD patients.

2018 update of expert consensus statement on antiplatelet therapy in East Asian patients with ACS or undergoing PCI

East Asians are the most populous race in the world and their health status is an important global issue. Compared with Caucasian populations, East Asian patients have a different benefit/risk ratio when using antithrombotic treatment. Despite this observation, treatment strategies in East Asian patients are mostly based on the American and European guidelines. Despite a lower platelet inhibitory response to clopidogrel, East Asian patients show a similar or even a lower rate of ischemic event occurrence and higher bleeding risk compared with Caucasian patients. For potent P2Y₁₂ inhibitors (ticagrelor and prasugrel), East Asian patients have shown less favorable net clinical benefits compared with Caucasian patients, which may be related to differences in pharmacokinetic/pharmacodynamic profiles and therapeutic zone of antiplatelet effect. This updated consensus mainly focuses on state-of-the-art and current controversies in the East Asian population. In addition, when East Asian patients are administered potent P2Y₁₂ receptor inhibitors, the strategies and ongoing trials to overcome the related hurdles are discussed.

Anticoagulation risk assessment for patients with non-valvular atrial fibrillation and venous thromboembolism: A clinical review

Non-valvular atrial fibrillation and venous thromboembolism anticoagulation risk assessment tools have been increasingly utilized to guide implementation and duration of anticoagulant therapy. Anticoagulation significantly reduces stroke and recurrent venous thromboembolism risk, but comes at the cost of increased risk of major and clinically relevant non-major bleeding. The decision for anticoagulation in high-risk patients is complicated by the fact that many risk factors associated with increased thromboembolic risk are simultaneously associated with increased bleeding risk. Traditional risk assessment tools rely heavily on age, sex, and presence of cardiovascular comorbidities, with newer tools additionally taking into account changes in risk factors over time and novel biomarkers to facilitate more personalized risk assessment. These tools may help counsel and inform patients about the risks and benefits of starting or continuing anticoagulant therapy and can identify patients who may benefit from more careful management. Although the ability to predict anticoagulant-associated hemorrhagic risk is modest, ischemic and bleeding risk scores have been shown to add significant value to therapeutic management decisions. Ultimately, further work is needed to optimally implement accurate and actionable risk stratification into clinical practice.

Efficacy and Safety of the Use of Non-vitamin K Antagonist Oral Anticoagulants in Patients with Ischemic Heart Disease: A Meta-Analysis of Phase III Randomized Trials

BACKGROUND

There are conflicting published data on non-vitamin K antagonist oral anticoagulants (NOACs), with varying evidence of benefit or harm in acute coronary syndrome (ACS) and non-ACS cohorts. To explore the efficacy and safety of NOAC use in patients with ischemic heart disease (IHD), we conducted a meta-analysis of phase III randomized controlled trials (RCTs).

METHODS

We systematically searched the Cochrane Library, PubMed, and Embase databases. A random-effect model was selected to pool the effect measurement estimates (hazard ratios [HRs] and 95% confidence intervals [CIs]).

RESULTS

Three RCTs with 39,492 enrolled IHD patients were included. Compared with placebo, NOACs were associated with reduced risks of major adverse cardiac events (MACE) (HR 0.83, 95% CI 0.76-0.90), cardiovascular death (HR 0.82, 95% CI 0.72-0.93), and myocardial infarction (HR 0.87, 95% CI 0.78-0.97) accompanied by increased risks of major bleeding (HR 2.46, 95% CI 1.42-4.26), but not fatal bleeding (HR 1.35, 95% CI 0.76-2.39) or intracranial hemorrhage (HR 2.19, 95% CI 0.91-5.27). Subgroup analysis revealed that NOACs were associated with an increased risk of major bleeding in patients who received dual antiplatelet therapy compared with patients who received single antiplatelet therapy (3.01, 1.82-4.98 vs. 1.66, 1.37-2.03; P for interaction 0.03) and patients with ACS compared with patients with non-ACS (3.27, 2.16-4.95 vs. 1.66, 1.36-2.02; P for interaction 0.004).

CONCLUSIONS

In patients with IHD, NOACs confer protection against thrombosis-related complications, but at the cost of an increased hazard of major bleeding. NOACs plus a single antiplatelet drug seem to be a good choice for patients with IHD.

Inhibitory mechanisms of very low-dose rivaroxaban in non-ST-elevation myocardial infarction

Very low-dose (VLD) factor Xa (FXa) inhibition, in combination with acetylsalicylic acid (ASA) and clopidogrel, is associated with improved outcomes in patients with acute coronary syndrome (ACS) with a tolerable bleeding risk profile. To date, there are no data documenting platelet inhibition and the anticoagulatory effects of VLD FXa inhibition on top of guideline-adherent dual-antiplatelet therapy (DAPT) in patients with ACS. Patients with non-ST-elevation myocardial infarction (NSTEMI) receiving oral DAPT (ASA + clopidogrel, n = 20; or ASA + ticagrelor, n = 20) were prospectively enrolled in a nonrandomized study. Coagulation- and platelet-dependent thrombin generation (TG), measured by means of the calibrated automated thrombogram, were significantly decreased after in vitro and in vivo addition of rivaroxaban. As shown by a total thrombus-formation analysis approach, rivaroxaban treatment led to a significantly decreased coagulation-dependent (AR-chip) thrombus formation in patients treated with ASA plus P2Y₁₂ inhibitor (clopidogrel/ticagrelor), whereas the pure platelet-dependent (PL-chip) thrombus formation was not affected at all. Adjunctive rivaroxaban therapy was not associated with significant differences in platelet aggregation assessed by light-transmission aggregometry (LTA). Nevertheless, according to fluorescence-activated cell sorter analysis, VLD rivaroxaban treatment resulted in a significantly reduced expression of platelet HMGB-1, whereas P-selectin exposure was not affected. Furthermore, an enhanced effect of rivaroxaban on total thrombus formation and TG was observed in particular in clopidogrel nonresponder patients defined as adenosine 5'-diphosphate-induced LTA ≥40%. VLD rivaroxaban reduces thrombus formation and platelet-dependent TG in patients with ACS receiving DAPT, which can be of potential ischemic benefit. This trial was registered at www.clinicaltrials.gov as #NCT01417884.

Direct Oral Anticoagulants in Addition to Antiplatelet Therapy for Secondary Prevention after Acute Coronary Syndromes: a Review

PURPOSE OF REVIEW

As the management of acute coronary syndrome (ACS) continues to evolve, many old practices proved to be of a little benefit and other approaches established the new pillars of modern medicine. Treating ACS patients with dual antiplatelet therapy (DAPT) for a year by combining aspirin and a P2Y12 inhibitor (clopidogrel, ticagrelor, or prasugrel) has resulted in better outcomes and is currently the standard of therapy. However, owing to the persistent activation of the coagulation cascade, patients may continue to experience recurrent ischemia and high mortality rates despite compliance with the dual antiplatelet therapy. Research is underway to establish new treatment modalities for secondary prevention post-ACS, including the use of the novel direct oral anticoagulants (DOACs).

RECENT FINDINGS

Multiple trials have been conducted to evaluate the use of DOACs for the secondary prevention after ACS. Recent emerging data showed that the addition of rivaroxaban in a very low dose of 2.5 mg twice daily to the regular DAPT regimen after ACS is beneficial in the reduction of major cardiovascular events, including recurrent myocardial infarction (MI) and strokes. On the other hand, other DOACs, including apixaban, did not show similar efficacy and did not improve the cardiovascular outcomes. Patients who experience an ACS continue to suffer long-term consequences and thromboembolic complications. Many studies have shown that after the initial ACS event, patients remain in a hypercoagulable state and are more prone to recurrent ischemic attacks including stroke, recurrent MI, or unstable angina (UA). With the objective of seeking better outcomes, it is imperative to explore more aggressive anticoagulation strategies in ACS patients. In this article, we discuss the progress that was made and the limitations we face regarding the role of different anticoagulants in this setting.

[Interventional angiology : Endovascular treatment of chronic and acute limb ischemia]

The development of new technologies and techniques has significantly advanced the field of endovascular peripheral interventions for chronic and acute limb ischemia over the last 20 years. Nowadays, the majority of patients with symptomatic peripheral arterial occlusive disease can be treated percutaneously using an endovascular first approach as a minimally invasive alternative to classical bypass surgery. Balloon angioplasty and stent implantation are the mainstays of endovascular interventions. For reconstruction of complex aortoiliac occlusions covered stents are frequently used. Patency rates after femoropopliteal interventions have been improved by the introduction of drug-eluting balloon and stent technologies. Advances in material and access techniques now enable the successful endovascular treatment of more complex infrapopliteal stenoses and occlusions.

Sortilin levels are associated with peripheral arterial disease in type 2 diabetic subjects

BACKGROUND

Sortilin is a 95-kDa protein which has recently been linked to circulating cholesterol concentration and lifetime risk of developing significant atherosclerotic disease. Sortilin is found inside different cell types and circulating in blood. Higher circulating sortilin concentration has been found in patients with coronary atherosclerosis compared to control subjects. Sortilin concentration is influenced by statin therapy.

METHODS

We enrolled statin-naïve subjects with type 2 diabetes mellitus and we performed a cross-sectional study to evaluate the association between sortilin levels and the presence of clinically significant lower limb peripheral artery disease (PAD) in a population of statin-free diabetic subjects.

RESULTS

Out of the 154 patients enrolled in our study, 80 patients were free from PAD, while 74 had clinically significant PAD. Sortilin concentration was significantly higher in the latter group compared to the former (1.61 ± 0.54 ng/mL versus 0.67 ± 0.30 ng/mL, P < 0.01) and there was a trend toward increased sortilin levels as disease severity increased. The association of sortilin levels with PAD remained after adjusting for major risk factors in a multivariate analysis.

CONCLUSIONS

We showed that sortilin is significantly and independently associated with the presence of lower limb PAD in a statin-free diabetic population and it may be a promising marker for clinically significant atherosclerosis of the lower limbs. Further studies are needed to confirm this finding and to evaluate its clinical usefulness.

Direct oral anticoagulants and vitamin K antagonists are linked to differential profiles of cardiac function and lipid metabolism

BACKGROUND

Experimental data indicate that direct acting oral anticoagulants (DOAC) and vitamin K antagonists (VKA) may exert differential effects on cardiovascular disease.

METHODS

Data from the prospective, observational, single-center MyoVasc Study were used to examine associations of DOAC as compared to VKA with subclinical markers of cardiovascular disease, cardiac function, and humoral biomarkers in heart failure (HF).

RESULTS

Multivariable analysis adjusted for age, sex, traditional cardiovascular risk factors, comorbidities, and medications with correction for multiple testing demonstrated that DOAC therapy was among all investigated parameters an independent significant predictor of better diastolic function (E/E': β - 0.24 [- 0.36/- 0.12]; P < 0.0001) and higher levels of ApoA1 (β + 0.11 g/L [0.036/0.18]; P = 0.0038) compared to VKA therapy. In propensity score-weighted analyses, the most pronounced differences between DOAC and VKA-based therapy were also observed for E/E' (∆ - 2.36) and ApoA1 (∆ + 0.06 g/L). Sensitivity analyses in more homogeneous subsamples of (i) individuals with AF and (ii) individuals with asymptomatic HF confirmed the consistency and robustness of these findings. In the comparison of factor IIa and Xa-directed oral anticoagulation, no differences were observed regarding cardiac function (E/E' ratio: β_{IIa inhibitor} - 0.22 [- 0.36/- 0.08] vs. β_{Xa inhibitor} - 0.24 [- 0.37/- 0.11]) and lipid metabolism (ApoA1: β_{IIa inhibitor} 0.10 [0.01/0.18] vs. β_{Xa inhibitor} 0.12 [0.04/0.20]) compared to VKA therapy.

CONCLUSION

This study provides the first evidence for differential, non-conventional associations of oral anticoagulants on cardiac function and lipid metabolism in humans. The potentially beneficial effect of DOACs in the highly vulnerable population of HF individuals needs to be further elucidated and may have implications for individually tailored anticoagulation therapy.

Advances in Antithrombotic Therapy

Thrombosis remains a major cause of morbidity and mortality. Consequently, advances in antithrombotic therapy are needed to reduce the disease burden. This article focuses on 2 such advances. First, the prevention of atherothrombosis in patients with coronary or peripheral artery disease, which has been enhanced by the finding that the combination of low-dose rivaroxaban plus aspirin is superior to aspirin alone for prevention of recurrent ischemic events. However, this benefit comes at the cost of increased bleeding albeit not fatal bleeding. To overcome this problem, the second advance is the identification of factor XI as a target for new anticoagulants that are potentially safer than those currently available.

Comparison of Frequency of Ischemic Stroke in Patients With Versus Without Coronary Heart Disease and Without Atrial Fibrillation

Recent trials of antithrombotic therapy in patients with coronary artery disease (CAD) have demonstrated substantial reductions in ischemic stroke. Our aim was to examine ischemic stroke risk in patients with CAD and to identify those at highest risk. We examined ischemic stroke risk in patients without atrial fibrillation who underwent coronary angiography between 2004 and 2012. Patients were stratified according to presence or absence of CAD and further stratified by extent of CAD (0 vessel disease [VD], 1 VD, 2 VD, 3 VD, and diffuse VD). End points were composites of ischemic stroke, transient ischemic attack (TIA), and systemic embolism, as well as major adverse cardiovascular and cerebrovascular events (MACCE) defined as cardiac death, myocardial infarction, plus ischemic stroke, TIA, and systemic embolism. Adjusted incidence rate ratios (IRRs) were estimated. A total of 68,829 patients were included, 25,032 had 0 VD, 4,736 had diffuse VD, 18,471 had 1 VD, 10,588 had 2 VD, and 10,002 had 3 VD. Median follow-up was 4.0 years. CAD extent was associated with an increased risk of stroke, TIA, and systemic embolism (1 VD: adjusted IRR 1.02, 95% confidence interval [CI] 0.90 to 1.16; diffuse VD: adjusted IRR 1.22, 95% CI 1.02 to 1.47; 2 VD: adjusted IRR 1.28, 95% CI 1.12 to 1.45; 3 VD: adjusted IRR 1.37, 95% CI 1.20 to 1.55) compared with patients with 0 VD. Presence and extent of CAD were also associated with MACCE. In conclusion, CAD is associated with an increased risk of stroke, TIA, and systemic embolism and MACCE in patients without atrial fibrillation, and patients with coronary multi-VD are at highest risk and may be candidates for treatment strategies aiming at reducing ischemic stroke incidence.

Trends in management and outcome of patients with non-ST elevation acute coronary syndromes and peripheral arterial disease

OBJECTIVE

Patients with non ST-segment elevation acute coronary syndromes (NSTE-ACS) and peripheral arterial disease (PAD) present a worse prognosis compared to those without PAD. We sought to describe contemporary trends of in-hospital management and outcome of patients admitted for NSTE-ACS with associated PAD.

METHODS

We analyzed data from 6 Italian nationwide registries, conducted between 2001 and 2014, including consecutive NSTE-ACS patients.

RESULTS

Out of 15,867 patients with NSTE-ACS enrolled in the 6 registries, 2226 (14.0%) had a history of PAD. As compared to non-PAD patients, those with PAD had significantly more risk factors and comorbidities (all p < 0.0001) that increased over time. Patients with PAD underwent less frequently coronary angiography (72.0% vs 79.2%, p < 0.0001) and percutaneous coronary intervention (PCI, 42.9% vs 51.8%, p < 0.0001), compared to patients without PAD. Over the years, a progressive and similar increase occurred in the rates of invasive procedures both in patients with and without PAD (both p for trend <0.0001). The crude in-hospital mortality rate did not significantly change over time (p for trend = 0.83). However, as compared to 2001, the risk of death was significantly lower in all other studies performed at different times, after adjustment for multiple comorbidities.. At multivariable analysis, PAD on admission was an independent predictor of in-hospital mortality [odds ratio (OR): 1.75; 95% confidence intervals (CI): 1.35-2.27; p < 0.0001].

CONCLUSIONS

Over the 14 years of observation, patients with PAD and NSTE-ACS exhibited worsening baseline characteristics and a progressive increase in invasive procedures. Whereas crude in-hospital mortality did not change over time, we observed a significant reduction in comorbidity-adjusted mortality, as compared to 2001.

Do We Need Potent Intravenous Antiplatelet Inhibition at the Time of Reperfusion During ST-Segment Elevation Myocardial Infarction?

Acute myocardial infarction (MI) is still a large source of morbidity and mortality worldwide. Although early reperfusion therapy has been prioritized in the modern era of percutaneous coronary intervention and thrombolysis, attempts at incremental improvements in clinical outcomes by reducing MI size have not been successful so far. Herein, we review the studies that have evaluated immediate-onset antiplatelet therapy as attempts to improve meaningful clinical outcomes in ST-segment elevation MI (STEMI). Unfortunately, many of the adjunctive pharmacotherapies have proven to be disappointing. Recent studies performed in the background of routine oral administration of P2Y₁₂ adenosine receptor inhibitors, which may take several hours to take full effect, and aspirin have largely shown no improvement in outcomes, despite an earlier onset of antiplatelet activity of the investigative agents. Further progress in improving outcomes during STEMI may depend on exploring therapeutics that modulate the pathophysiology of microvascular damage during ischemia-reperfusion injury, a phenomenon whose effects evolve over hours to days. We speculate that the dynamic nature of the no-reflow phenomenon may be an explanation for these disappointing results with the intravenous antiplatelet agents. We hope that appreciation for what has not worked in this domain may direct future research efforts to focus on novel pathways. Myocardial ischemia and reperfusion injury are very much still a lingering issue. Despite significant improvements in door-to-balloon times, rates of in-hospital mortality for STEMI remain unchanged. Outcomes following successfully reperfused STEMI are likely determined by the initial size of myocardial necrosis (ie, cardiomyocyte death during the period of ongoing ischemia), patency of the infarct-related epicardial coronary artery, possible reperfusion injury, the microvascular no-reflow phenomenon, and adverse remodeling after infarction.

[Treatment with oral anticoagulants in older patients: Should warfarin still be prescribed?]

Vitamin-K antagonists (VKA) have been the standard for oral anticoagulation. However, they carry several problems in older patients: frequent bleeding complications, complex management, risk of interactions with multiple drugs. Two classes of direct oral anticoagulants (DOA) are currently available in France: (a) direct thrombin inhibitors: dabigatran; and (b) direct factor Xa inhibitors: rivaroxaban, apixaban and others. Their management is easier: quickly effective after administration, they are given at fixed doses and do not need regular laboratory monitoring. Several randomized trials have shown that DOA are non-inferior to VKA for treating venous thromboembolic disease (prophylactic or curative treatment) and atrial fibrillation (prevention of associated embolisms). DOA might be also effective for long-term treatment of coronary disease, in some cases. No trial has specifically studied older patients. In the context of atrial fibrillation, subgroup analysis show similar results between patients above and below 75-years-old. Lower doses of dabigatran and apixaban should be used in many older people. All DOA are eliminated at least partly by kidneys. Their dose must be reduced in moderate renal failure (filtration glomerular rate (FGR) 30 to 50mL/min) and they are contraindicated in older patients with severe renal failure (FGR<30mL/min). DOA also have other problems: (a) important drug interactions are still possible, (b) the clinical application of specific coagulation tests need to be defined, (c) their safety in some subgroups of elderly patients, very different from patients included in clinical trials, is not known.

Anti-platelet and anti-coagulant therapy in peripheral arterial disease prior to surgical intervention

OBJECTIVE

Peripheral artery disease is a major clinical co-morbidity that can significantly affect quality of life, especially in the presence of diabetes mellitus and older age. The focus of this literature review is on medical management, through anti-platelet and anti-coagulation, of peripheral artery disease prior to undergoing surgical or endovascular management.

METHOD

Extensive electronic literature search performed in four major databases (PubMed, SCOPUD, Embase and Ovid) to identify the published randomized and non-randomized studies that compared and discussed the management of peripheral artery disease with different anti-thrombotic agents.

RESULTS

A total of 17 studies were identified to meet the inclusion criteria of this review. Among them, 4 were systematic review and meta-analyses, 1 was observational study and 12 were randomized controlled trials. The reported outcomes in each study are summarized and reported separately within this review.

CONCLUSION

Peripheral artery disease is a complex and multifactorial clinical condition. The use of dual anti-platelets, such as aspirin and clopidogrel, are the key in preventing major cardiovascular events as well as stroke and death. Utilization of anti-coagulation such as direct oral anti-coagulants' as additional parameters for the prevention of disease progression, is paramount. Eventually, the choice of either dual-antiplatelet therapy or combined anti-coagulation with anti-platelets should be carefully considered, particularly following the most recent published debatable studies.

Cost-effectiveness of low-dose rivaroxaban and aspirin versus aspirin alone in people with peripheral or carotid artery disease: An Australian healthcare perspective

Aims

Peripheral artery disease affects 1.2% of the population globally and is associated with an increased risk of atherothrombotic cardiovascular events, major adverse limb events and mortality. The Cardiovascular Outcomes for People Using Anti-coagulation Strategies (COMPASS) trial demonstrated positive results of rivaroxaban plus aspirin therapy compared to aspirin therapy alone in those with peripheral artery disease or carotid artery disease. We sought to estimate the cost-effectiveness from the Australian healthcare system perspective.

Methods and results

A Markov model was developed to simulate the experiences of a hypothetical population of 1000 individuals with peripheral artery disease or carotid artery disease, profiled on the COMPASS trial, treated with rivaroxaban plus aspirin therapy versus aspirin therapy alone. With each annual cycle, individuals were at risk of having non-fatal cardiovascular disease events, major adverse limb events, or dying. Individuals were also at risk of non-fatal major bleeding. The model had a lifetime time horizon. Costs and utilities were sourced from the literature and discounted at 5.0% annually. Rivaroxaban plus aspirin therapy prevented 143 non-fatal cardiovascular disease events, 118 major adverse limb events and 10 deaths compared to aspirin therapy alone. Conversely, 156 additional major non-fatal bleeds were accrued. With an additional 256 quality-adjusted life years gained, at an additional cost of AUD$6,858,103, the incremental cost-effectiveness ratio was AUD$26,769 (discounted) per quality-adjusted life year gained, which is below Australia’s arbitrary willingness to pay threshold of AUD$50,000.

Conclusion

In those with peripheral artery disease or carotid artery disease, rivaroxaban plus aspirin therapy is effective and cost-effective in the prevention of recurrent cardiovascular disease compared to aspirin therapy alone.

Influence of age on the pharmacokinetics, pharmacodynamics, efficacy, and safety of rivaroxaban

OBJECTIVE

Atrial fibrillation, peripheral and coronary artery disease, and venous thromboembolism are major risk factors for stroke, disability, and death in the rapidly growing older (≥ 65 years.) population. In the absence of clear guidelines on the appropriate use of the newer non-vitamin K antagonist oral anticoagulants in this population, this study specifically reviews the available literature for rivaroxaban and the impact of age that may affect the pharmacokinetics, pharmacodynamics, efficacy, and safety of this anticoagulant.

METHODS

This review includes a summary of data obtained from the available literature concerning both older healthy subjects and older patients with various aspects of cardiovascular disease enrolled in rivaroxaban clinical trials and data from real world evidence studies.

RESULTS

Evaluation of the clinical pharmacology in healthy, older adults reveal no clinically relevant effect of age on rivaroxaban pharmacokinetics and pharmacodynamics. Population pharmacokinetic studies in older patients with thromboembolic diseases suggest a moderate effect of increasing age on rivaroxaban clearance, albeit not clinically significant. Additionally, sub-group analyses from large, phase 3 clinical trials demonstrate consistent efficacy and safety in the older patient population vs the overall population. These findings are further supported by real-world evidence studies.

CONCLUSION

A favorable clinical profile with rivaroxaban was observed across age sub-groups, supporting the premise that dosing in older adults does not necessitate adjustment. However, it is prudent that a cautious and individualized approach is taken for treatment with any anticoagulant in older adults.