Atherosclerosis evaluation and cardiovascular risk estimation using coronary computed tomography angiography.

Clinical risk scores based on traditional risk factors of atherosclerosis correlate imprecisely to an individual's complex pathophysiological predisposition to atherosclerosis and provide limited accuracy for predicting major adverse cardiovascular events (MACE). Over the past two decades, computed tomography scanners and techniques for coronary computed tomography angiography (CCTA) analysis have substantially improved, enabling more precise atherosclerotic plaque quantification and characterization. The accuracy of CCTA for quantifying stenosis and atherosclerosis has been validated in numerous multicentre studies and has shown consistent incremental prognostic value for MACE over the clinical risk spectrum in different populations. Serial CCTA studies have advanced our understanding of vascular biology and atherosclerotic disease progression. The direct disease visualization of CCTA has the potential to be used synergistically with indirect markers of risk to significantly improve prevention of MACE, pending large-scale randomized evaluation.

Rivaroxaban for Prevention of Thrombotic Events, Hospitalization, and Death in Outpatients With COVID-19: A Randomized Clinical Trial.

BACKGROUND: COVID-19 (coronavirus disease 2019) is associated with heightened risks of venous and arterial thrombosis and hospitalization due to respiratory failure. To assess whether prophylactic anticoagulation can safely reduce the frequency of venous and arterial thrombosis, hospitalization, and death in nonhospitalized patients with symptomatic COVID-19 and at least one thrombosis risk factor, we conducted the PREVENT-HD double-blind, placebo-controlled randomized trial (A Study of Rivaroxaban to Reduce the Risk of Major Venous and Arterial Thrombotic Events, Hospitalization and Death in Medically Ill Outpatients With Acute, Symptomatic COVID-19] Infection). METHODS: PREVENT-HD was conducted between August 2020 and April 2022 at 14 US integrated health care delivery networks. A virtual trial design used remote informed consent and clinical monitoring and facilitated data collection through electronic health record integration with a cloud-based research platform. Nonhospitalized patients with symptomatic COVID-19 and at least one thrombosis risk factor were enrolled and randomly assigned to either 10 mg of oral rivaroxaban or placebo daily for 35 days. The primary efficacy outcome was time to first occurrence of a composite of symptomatic venous thromboembolism, myocardial infarction, ischemic stroke, acute limb ischemia, non-central nervous system systemic arterial embolism, hospitalization, or death through day 35. The principal safety end point was International Society on Thrombosis and Hemostasis critical-site or fatal bleeding. The last study visit was on day 49. RESULTS: The study was terminated prematurely because of enrollment challenges and a lower-than-expected blinded pooled event rate. A total of 1284 patients underwent randomization with complete accrual of primary events through May 2022. No patients were lost to follow-up. The primary efficacy outcome occurred in 22 of 641 in the rivaroxaban group and 19 of 643 in the placebo group (3.4% versus 3.0%; hazard ratio, 1.16 [95% CI, 0.63-2.15]; P=0.63). No patient in either group experienced critical-site or fatal bleeding. One patient receiving rivaroxaban had a major bleed. CONCLUSIONS: The study was terminated prematurely after enrollment of 32% of planned accrual because of recruitment challenges and lower-than-expected event rate. Rivaroxaban prescribed for 35 days in nonhospitalized patients with symptomatic COVID-19 at risk for thrombosis did not appear to reduce a composite end point of venous and arterial thrombotic events, hospitalization, and death. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT04508023.

Novel Tissue Factor Inhibition for Thromboprophylaxis in COVID-19: Primary Results of the ASPEN-COVID-19 Trial.

BACKGROUND: Thrombo-inflammation is central to COVID-19-associated coagulopathy. TF (tissue factor), a driver of disordered coagulation and inflammation in viral infections, may be a therapeutic target in COVID-19. The safety and efficacy of the novel TF inhibitor rNAPc2 (recombinant nematode anticoagulation protein c2) in COVID-19 are unknown. METHODS: ASPEN-COVID-19 was an international, randomized, open-label, active comparator clinical trial with blinded end point adjudication. Hospitalized patients with COVID-19 and elevated D-dimer levels were randomized 1:1:2 to lower or higher dose rNAPc2 on days 1, 3, and 5 followed by heparin on day 8 or to heparin per local standard of care. In comparisons of the pooled rNAPc2 versus heparin groups, the primary safety end point was major or nonmajor clinically relevant International Society of Thrombosis and Haemostasis bleeding through day 8. The primary efficacy end point was proportional change in D-dimer concentration from baseline to day 8, or discharge if before day 8. Patients were followed for 30 days. RESULTS: Among 160 randomized patients, median age was 54 years, 43.1% were female, and 38.8% had severe baseline COVID-19. There were no significant differences between rNAPc2 and heparin in bleeding or other safety events. Overall, median change in D-dimer was -16.8% (interquartile range, -45.7 to 36.8; P=0.41) with rNAPc2 treatment and -11.2% (-36.0 to 34.4; P=0.91) with heparin (Pintergroup=0.47). In prespecified analyses, in severely ill patients, D-dimer levels tended to increase more within the heparin (median, 29.0% [-14.9 to 145.2]; P=0.02) than the rNAPc2 group (median, 25.9% [-49.1 to 136.4]; P=0.14; Pintergroup=0.96); in mildly ill patients, D-dimer levels were reduced within each group with a numerically greater reduction with rNAPc2 versus heparin (rNAPc2 median, -32.7% [-44.7 to 4.3]; P=0.007 and heparin median, -16.8% [-36.0 to 0.5]; P=0.008, Pintergroup=0.34). CONCLUSIONS: rNAPc2 treatment in hospitalized patients with COVID-19 was well tolerated without excess bleeding or serious adverse events but did not significantly reduce D-dimer more than heparin at day 8. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT04655586.

Reduction in Acute Limb Ischemia With Rivaroxaban Versus Placebo in Peripheral Artery Disease After Lower Extremity Revascularization: Insights From VOYAGER PAD.

BACKGROUND: Patients with peripheral artery disease (PAD) are at heightened risk of acute limb ischemia (ALI), a thrombotic event associated with amputation, disability, and mortality. Previous lower extremity revascularization (LER) is associated with increased ALI risk in chronic PAD. However, the pattern of risk, clinical correlates, and outcomes after ALI early after LER are not well-studied, and effective therapies to reduce ALI post-LER are lacking. METHODS: The VOYAGER PAD trial (Vascular Outcomes Study of ASA [Acetylsalicylic Acid] Along With Rivaroxaban in Endovascular or Surgical Limb Revascularization for PAD; rNCT02504216) randomized patients with PAD undergoing LER to rivaroxaban 2.5 mg twice daily or placebo on a background of low-dose aspirin. The primary outcome was a composite of ALI, major amputation of vascular cause, myocardial infarction, ischemic stroke, or cardiovascular death. ALI was prospectively ascertained and adjudicated by a blinded committee. The cumulative incidence of ALI was calculated using Kaplan-Meier estimates, and Cox proportional hazards models were used to generate hazard ratios and associated CIs. Analyses were performed as intention-to-treat. RESULTS: Among 6564 patients followed for a median of 2.3 years, 382 (5.8%) had a total of 508 ALI events. In placebo patients, the 3-year cumulative incidence of ALI was 7.8%. After multivariable modeling, previous LER, baseline ankle-brachial index <0.50, surgical LER, and longer target lesion length were associated with increased risk of ALI. Incident ALI was associated with subsequent all-cause mortality (hazard ratio [HR], 2.59 [95% CI, 1.98-3.39]) and major amputation (HR, 24.87 [95% CI, 18.68-33.12]). Rivaroxaban reduced ALI relative to placebo by 33% (absolute risk reduction, 2.6% at 3 years; HR, 0.67 [95% CI, 0.55-0.82]; P=0.0001), with benefit starting early (HR, 0.45 [95% CI, 0.24-0.85]; P=0.0068 at 30 days). Benefit was present for severe ALI (associated with death, amputation, or prolonged hospitalization and intensive care unit stay, HR, 0.58 [95% CI, 0.40-0.83]; P=0.003) and regardless of LER type (surgical versus endovascular revascularization, P interaction=0.42) or clopidogrel use (P interaction=0.59). CONCLUSIONS: After LER for symptomatic PAD, ALI is frequent, particularly early after LER, and is associated with poor prognosis. Low-dose rivaroxaban plus aspirin reduces ALI after LER, including ALI events associated with the most severe outcomes. The benefit of rivaroxaban for ALI appears early, continues over time, and is consistent regardless of revascularization approach or clopidogrel use.

Rationale and design of a study to assess the safety and efficacy of rNAPc2 in COVID-19: the Phase 2b ASPEN-COVID-19 trial.

BACKGROUND: The interaction between thrombosis and inflammation appears central to COVID-19-associated coagulopathy and likely contributes to poor outcomes. Tissue factor is a driver of disordered coagulation and inflammatory signaling in viral infections and is important for viral replication; therefore, tissue factor may be an important therapeutic target in COVID-19. STUDY DESIGN: ASPEN-COVID-19 (NCT04655586) is a randomized, prospective open-label blinded endpoint (PROBE), active comparator Phase 2b trial to evaluate the safety and efficacy of recombinant Nematode Anticoagulant Protein c2 (rNAPc2), a potent tissue factor inhibitor, in patients hospitalized with COVID-19 with elevated D-dimer levels. This report describes the design of the Phase 2b dose ranging and proof of concept study. Participants are randomly assigned, in a 1:1:2 ratio, to lower or higher dose rNAPc2 by subcutaneous injection on days 1, 3, and 5 or to heparin according to local standard of care; randomization is stratified by baseline D-dimer level (at 2X upper limit of normal). The primary efficacy endpoint for Phase 2b is proportional change in D-dimer concentration from baseline to Day 8 or day of discharge, whichever is earlier. The primary safety endpoint is major or non-major clinically relevant bleeding through Day 8. Phase 2b enrollment began in December 2020 and is projected to complete ∼160 participants by Q4 2021. CONCLUSIONS: ASPEN-COVID-19 will provide important data on a novel therapeutic approach that may improve outcomes in hospitalized COVID-19 patients beyond available anticoagulants by targeting tissue factor, with potential effects on not only thrombosis but also inflammation and viral propagation.

LEGACY: Phase 2a Trial to Evaluate the Safety, Pharmacokinetics, and Pharmacodynamic Effects of the Anti-EL (Endothelial Lipase) Antibody MEDI5884 in Patients With Stable Coronary Artery Disease.

OBJECTIVE: Functional HDL (high-density lipoprotein) particles that facilitate cholesterol efflux may be cardioprotective. EL (endothelial lipase) hydrolyzes phospholipids promoting catabolism of HDL and subsequent renal excretion. MEDI5884 is a selective, humanized, monoclonal, EL-neutralizing antibody. We sought to determine the safety, pharmacokinetics, and pharmacodynamic effects of multiple doses of MEDI5884 in patients with stable coronary artery disease. Approach and Results: LEGACY was a phase 2a, double-blind, placebo-controlled, parallel-design trial that randomized 132 patients with stable coronary artery disease receiving high-intensity statin therapy to 3 monthly doses of 1 of 5 dose levels of MEDI5884 (50, 100, 200, 350, or 500 mg SC) or matching placebo. The primary end point was the safety and tolerability of MEDI5884 through the end of the study (day 151). Additional end points included change in HDL cholesterol and cholesterol efflux from baseline to day 91, hepatic uptake of cholesterol at day 91, changes in various other lipid parameters. The incidence of adverse events was similar between the placebo and MEDI5884 groups. In a dose-dependent manner, MEDI5884 increased HDL cholesterol up to 51.4% (P<0.0001) and global cholesterol efflux up to 26.2% ([95% CI, 14.3-38.0] P<0.0001). MEDI5884 increased HDL particle number up to 14.4%. At the highest dose tested, an increase in LDL (low-density lipoprotein) cholesterol up to 28.7% (P<0.0001) and apoB (apolipoprotein B) up to 13.1% (P=0.04) was observed with MEDI5884. However, at the potential target doses for future studies, there was no meaningful increase in LDL cholesterol or apoB. CONCLUSIONS: Inhibition of EL by MEDI5884 increases the quantity and quality of functional HDL in patients with stable coronary artery disease on high-intensity statin therapy without an adverse safety signal at the likely dose to be used. These data support further clinical investigation. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03351738.

Improvement in walking impairment following surgical and endovascular revascularization: Insights from VOYAGER PAD.

BACKGROUND: Peripheral artery disease (PAD) affects 200 million people worldwide and is associated with impaired quality of life, increased morbidity, and mortality. Supervised exercise therapy (SET) and lower-extremity revascularization (LER) are both proven strategies to improve patient symptoms. Short and long-term functional outcomes after LER for symptomatic PAD in a large, international cohort have not previously been described. METHODS: The VOYAGER PAD trial (ClinicalTrials.gov identifier: NCT02504216) enrolled subjects after LER for symptomatic PAD (Rutherford category 2-6). Participants completed the Walking Impairment Questionnaire (WIQ) at baseline, 1, 3 and 6 months, and every 6 months thereafter. The primary outcome analysis was degree of difficulty walking two blocks at each of the aforementioned time points. Difficulty walking three blocks and climbing one flight of stairs at these time points was also analyzed. Data about supervised and home exercise therapy before or after revascularization were not collected in the VOYAGER PAD trial. RESULTS: Of the 5614 VOYAGER PAD participants completing the WIQ at baseline, three-quarters presented with claudication and one-quarter with critical limb ischemia. Of these, the majority (62% with claudication and 74% with CLI) reported inability or much difficulty walking two blocks prior to LER. Walking improved after LER regardless of revascularization strategy, but one-fifth with claudication and one-third with CLI reported continued inability or much difficulty walking two blocks 1 month after LER. Participants who reported improved walking ability 1 month after LER experienced a durable functional result out to 3 years. Although the proportion of participants reporting significant baseline difficulty climbing one flight of stairs or walking three blocks differed, the trend in immediate and sustained improvement after LER was similar to that observed for walking two blocks. CONCLUSION: In this large, international cohort undergoing LER for symptomatic PAD, nearly two-thirds reported inability or much difficulty walking two blocks at baseline. Although many participants reported improved walking ability after LER, a substantial proportion remained severely disabled. These observations may help motivate providers, patients, and medical systems to improve awareness and engagement in SET referral after LER.

Low-dose rivaroxaban plus aspirin in older patients with peripheral artery disease undergoing acute limb revascularization: insights from the VOYAGER PAD trial.

AIMS: In this secondary analysis of the VOYAGER trial, rivaroxaban 2.5 mg twice/day plus aspirin 100 mg/day was assessed in older adults. Advanced age is associated with elevated bleeding risk and unfavourable net benefit for dual antiplatelet therapy in chronic coronary artery disease. The risk-benefit of low-dose rivaroxaban in patients ≥75 years with peripheral artery disease (PAD) after lower extremity revascularization (LER) has not been described. METHODS AND RESULTS: The primary endpoint was a composite of acute limb ischaemia, major amputation, myocardial infarction, ischaemic stroke, or cardiovascular death. The principal safety outcome was thrombolysis in myocardial infarction (TIMI) major bleeding analysed by the pre-specified age cut-off of 75 years. Of 6564 patients randomized, 1330 (20%) were >75 years. Absolute 3-year Kaplan-Meier cumulative incidence rates for primary efficacy (23.4% vs. 19.0%) and safety (3.5% vs. 1.5%) endpoints were higher in elderly vs. non-elderly patients. Efficacy of rivaroxaban (P-interaction 0.83) and safety (P-interaction 0.38) was consistent irrespective of age. The combination of intracranial and fatal bleeding was not increased in patients >75 years (2 rivaroxaban vs. 8 placebo). Overall, benefits (absolute risk reduction 3.8%, number needed to treat 26 for the primary endpoint) exceeded risks (absolute risk increase 0.81%, number needed to harm 123 for TIMI major bleeding). CONCLUSION: Patients ≥75 years with PAD are at both heightened ischaemic and bleeding risk after LER. No excess harm with respect to major, intracranial or fatal bleeding was seen in older patients yet numerically greater absolute benefits were observed. This suggests that low-dose rivaroxaban combined with aspirin should be considered in PAD after LER regardless of age.

Rationale and design for the study of rivaroxaban to reduce thrombotic events, hospitalization and death in outpatients with COVID-19: The PREVENT-HD study.

BACKGROUND: COVID-19 is associated with both venous and arterial thrombotic complications. While prophylactic anticoagulation is now widely recommended for hospitalized patients with COVID-19, the effectiveness and safety of thromboprophylaxis in outpatients with COVID-19 has not been established. STUDY DESIGN: PREVENT-HD is a double-blind, placebo-controlled, pragmatic, event-driven phase 3 trial to evaluate the efficacy and safety of rivaroxaban in symptomatic outpatients with laboratory-confirmed COVID-19 at risk for thrombotic events, hospitalization, and death. Several challenges posed by the pandemic have necessitated innovative approaches to clinical trial design, start-up, and conduct. Participants are randomized in a 1:1 ratio, stratified by time from COVID-19 confirmation, to either rivaroxaban 10 mg once daily or placebo for 35 days. The primary efficacy end point is a composite of symptomatic venous thromboembolism, myocardial infarction, ischemic stroke, acute limb ischemia, non-central nervous system systemic embolization, all-cause hospitalization, and all-cause mortality. The primary safety end point is fatal and critical site bleeding according to the International Society on Thrombosis and Haemostasis definition. Enrollment began in August 2020 and is expected to enroll approximately 4,000 participants to yield the required number of end point events. CONCLUSIONS: PREVENT-HD is a pragmatic trial evaluating the efficacy and safety of the direct oral anticoagulant rivaroxaban in the outpatient setting to reduce major venous and arterial thrombotic events, hospitalization, and mortality associated with COVID-19.

Impact of chronic kidney disease on hemoglobin among patients with peripheral artery disease treated with P2Y12 inhibitors: Insights from the EUCLID trial.

Patients with chronic kidney disease may develop new or more severe anemia when treated with antiplatelet agents due to blood loss in conjunction with impaired erythropoiesis. Because anemia independently predicts limb amputation and mortality among patients with peripheral artery disease (PAD), we evaluated the relationship between estimated glomerular filtration rate (eGFR) and hemoglobin (Hb) levels in the EUCLID trial in which patients with symptomatic PAD were randomized to ticagrelor or clopidogrel. At baseline, 9025, 1870, and 1000 patients had eGFR ⩾ 60, 45-59, and < 45 mL/min/1.73 m2, respectively. The mean fall in Hb during the trial was 0.46 ± 1.68 g/dL and did not differ by baseline eGFR category, although Hb fall ⩾ 10% was more frequent among patients with lower eGFR (p for trend < 0.0001). On-study treatment with iron, erythropoiesis-stimulating agents, and/or red blood cell transfusion was reported for 479 (5.3%), 165 (8.8%), and 129 (12.9%) patients in the three eGFR categories, respectively (p for trend < 0.0001). After adjustment for baseline and post-randomization effects, those not receiving anemia treatment had a smaller reduction in Hb from baseline than those receiving anemia treatment (p < 0.0001). Other determinants of Hb reduction included absence of on-study myocardial infarction, coronary or peripheral revascularization, residence outside North America, male sex, and baseline eGFR. We conclude that among patients with PAD treated with P2Y12 inhibitors, lower baseline eGFR was associated with a greater reduction in Hb. ClinicalTrials.gov Identifier: NCT01732822.