Rationale and design for the randomized placebo-controlled double-blind trial studying the effect of single antiplatelet therapy (clopidogrel) versus dual antiplatelet therapy (clopidogrel/acetylsalicylic acid) on the occurrence of atherothrombotic events following lower extremity peripheral transluminal angioplasty (CLEAR-PATH)

RATIONALE

Antiplatelet therapy (APT) is the standard of care after endovascular revascularization (EVR) in patients with peripheral artery disease (PAD). APT aims to prevent both major adverse cardiovascular events (MACE) and major adverse limb events (MALE). Nonetheless, the rates of MACE and MALE after EVR remain high. In coronary artery and cerebrovascular disease, dual APT (DAPT)compared to acetylsalicylic acid alone has been proven to reduce MACE without increasing the risk of major bleeding when applied for a restricted number of weeks. However, within the PAD population, insufficient data are available to understand the potential attributable effect of DAPT over single APT (SAPT). Therefore, prospective randomized studies in targeted study populations are warranted.

TRIAL DESIGN

CLEAR-PATH is a Dutch multicenter, double-blind, placebo-controlled, randomized trial comparing SAPT (clopidogrel 75 mg plus placebo) with DAPT (clopidogrel 75 mg plus acetylsalicylic acid 80 mg) in patients with PAD undergoing EVR. CLEAR-PATH includes a time-to-event analysis with a follow-up of one year. The primary composite efficacy endpoint consists of all-cause mortality, nonfatal stroke, nonfatal myocardial infarction, severe limb ischemia, (indication for) re-intervention due to any symptomatic restenosis, re-occlusion, or due to acute limb ischemia, and major amputation. The primary safety endpoint contains major bleeding following the Thrombolysis in Myocardial Infarction classification. The enrolment started in August 2022. In total 450 primary efficacy outcome events are required which expectedly amounts to 1696 subjects. Recruitment will take approximately 36 months.

CONCLUSION

CLEAR-PATH will assess the efficacy and safety of DAPT compared to SAPT following EVR in PAD patients.

TRIAL REGISTRATION NUMBER

NL80009.041.21.

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.

Bleeding risk by intensity of anticoagulation in critically ill patients with COVID-19: A retrospective cohort study

BACKGROUND

Studies report hypercoagulability in coronavirus disease 2019 (COVID-19), leading many institutions to escalate anticoagulation intensity for thrombosis prophylaxis.

OBJECTIVE

To determine the bleeding risk with various intensities of anticoagulation in critically ill patients with COVID-19 compared with other respiratory viral illnesses (ORVI).

PATIENTS/METHODS

This retrospective cohort study compared the incidence of major bleeding in patients admitted to an intensive care unit (ICU) within a single health system with COVID-19 versus ORVI. In the COVID-19 cohort, we assessed the effect of anticoagulation intensity received on ICU admission on bleeding risk. We performed a secondary analysis with anticoagulation intensity as a time-varying covariate to reflect dose changes after ICU admission.

RESULTS

Four hundred and forty-three and 387 patients were included in the COVID-19 and ORVI cohorts, respectively. The hazard ratio of major bleeding for the COVID-19 cohort relative to the ORVI cohort was 1.26 (95% confidence interval [CI]: 0.86-1.86). In COVID-19 patients, an inverse-probability treatment weighted model found therapeutic-intensity anticoagulation on ICU admission had an adjusted hazard ratio of bleeding of 1.55 (95% CI: 0.88-2.73) compared with standard prophylactic-intensity anticoagulation. However, when anticoagulation was assessed as a time-varying covariate and adjusted for other risk factors for bleeding, the adjusted hazard ratio for bleeding on therapeutic-intensity anticoagulation compared with standard thromboprophylaxis was 2.59 (95% CI: 1.20-5.57).

CONCLUSIONS

Critically ill patients with COVID-19 had a similar bleeding risk as ORVI patients. When accounting for changes in anticoagulation that occurred in COVID-19 patients, therapeutic-intensity anticoagulation was associated with a greater risk of major bleeding compared with standard thromboprophylaxis.

Assessing the Risks of Bleeding vs Thrombotic Events in Patients at High Bleeding Risk After Coronary Stent Implantation: The ARC-High Bleeding Risk Trade-off Model

Importance

Patients who are candidates for percutaneous coronary intervention (PCI) and are at high bleeding risk constitute a therapeutic challenge because they often also face an increased risk of thrombotic complications.

Objectives

To develop and validate models to predict the risks of major bleeding (Bleeding Academic Research Consortium [BARC] types 3 to 5 bleeding) and myocardial infarction (MI) and/or stent thrombosis (ST) for individual patients at high bleeding risk and provide assistance in defining procedural strategy and antithrombotic regimens.

Design, Setting, and Participants

This prognostic study used individual patient data from 6 studies conducted from July 1, 2009, to September 5, 2017, for 6641 patients at more than 200 centers in Europe, the US, and Asia who underwent PCI and were identified as being at high bleeding risk using the Academic Research Consortium criteria. In 1 year of follow-up (excluding periprocedural events), individual patient risks of MI and/or ST and major bleeding were evaluated using 33 baseline variables. To validate these models, a subgroup of 1458 patients at high bleeding risk from the ONYX ONE trial were analyzed. Statistical analysis was performed from February 1, 2019, to April 30, 2020.

Exposures

All patients underwent PCI with bare metal, drug-coated, or drug-eluting stent implants.

Main Outcomes and Measures

Forward, stepwise multivariable proportional hazards models were used to identify highly significant predictors of MI and/or ST and BARC types 3 to 5 bleeding.

Results

A total of 6641 patients (4384 men [66.0%]; median age, 77.9 years [interquartile range, 70.0-82.6 years]) were included in this study. Over 365 days, nonperiprocedural MI and/or ST occurred in 350 patients (5.3%), and BARC types 3 to 5 bleeding occurred in 381 patients (5.7%). Eight independent baseline predictors of risk of MI and/or ST and 8 predictors for risk of BARC types 3 to 5 bleeding were identified. Four of these predictors were in both risk models. Both risk models showed moderate discrimination: C statistic = 0.69 for predicting MI and/or ST and 0.68 for predicting BARC types 3 to 5 bleeding. Applying these same models to the validation cohort gave a similar strength of discrimination (C statistic = 0.74 for both MI and/or ST and BARC types 3-5 bleeding). Patients with MI and/or ST had a mortality hazard ratio of 6.1 (95% CI, 4.8-7.7), and those with BARC types 3 to 5 bleeding had a mortality hazard ratio of 3.7 (95% CI, 2.9-4.8) compared with patients free of both events. Taking these data into account, the risk scores facilitate investigation of the individual patient trade-off between these 2 risks: 2931 patients (44.1%) at high bleeding risk in the 6 studies had a greater risk of MI and/or ST than of BARC 3 to 5 bleeding, 1555 patients (23.4%) had a greater risk of BARC 3 to 5 bleeding than of MI and/or ST, and 2155 (32.4%) had a comparable risk of both events.

Conclusions and Relevance

In a large cohort of patients at high bleeding risk undergoing PCI, 2 prognostic models have been developed to identify individual patients' risk of major coronary thrombotic and bleeding events. In future clinical practice, using an application on a smartphone to evaluate the trade-off between these 2 quantifiable risks for each patient may help clinicians choose the most appropriate revascularization strategy and tailor the duration and intensity of antithrombotic regimens.

Characterization of cardiovascular clinical events and impact of event adjudication on the treatment effect of darapladib versus placebo in patients with stable coronary heart disease: Insights from the STABILITY trial

BACKGROUND

Clinical Endpoint Classification (CEC) in clinical trials allows FOR standardized, systematic, blinded, and unbiased adjudication of investigator-reported events. We quantified the agreement rates in the STABILITY trial on 15,828 patients with stable coronary heart disease.

METHODS

Investigators were instructed to report all potential events. Each reported event was reviewed independently by 2 reviewers according to prespecified processes and prespecified end point definitions. Concordance between reported and adjudicated cardiovascular (CV) events was evaluated, as well as event classification influence on final study results.

RESULTS

In total, CEC reviewed 7,096 events: 1,064 deaths (696 CV deaths), 958 myocardial infarctions (MI), 433 strokes, 182 transient ischemic attacks, 2,052 coronary revascularizations, 1,407 hospitalizations for unstable angina, and 967 hospitalizations for heart failure. In total, 71.8% events were confirmed by CEC. Concordance was high (>80%) for cause of death and nonfatal MI and lower for hospitalization for unstable angina (25%) and heart failure (50%). For the primary outcome (composite of CV death, MI, and stroke), investigators reported 2,086 events with 82.5% confirmed by CEC. The STABILITY trial treatment effect of darapladib versus placebo on the primary outcome was consistent using investigator-reported events (hazard ratio 0.96 [95% CI 0.87-1.06]) or adjudicated events (hazard ratio 0.94 [95% CI 0.85-1.03]).

CONCLUSIONS

The primary outcome results of the STABILITY trial were consistent whether using investigator-reported or CEC-adjudicated events. The proportion of investigator-reported events confirmed by CEC varied by type of event. These results should help improve event identification in clinical trials to optimize ascertainment and adjudication.

Impact of bleeding assessment and adjudication methodology on event rates and clinical trial outcomes: insights from the HORIZONS-AMI trial

AIMS

Bleeding is a major safety outcome in cardiovascular trials. The present study assessed the impact of the adjudication process of bleeding events on three-year outcomes in the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial.

METHODS AND RESULTS

HORIZONS-AMI enrolled 3,602 patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention. An independent CEC reviewed 445 potential bleeding events identified from three sources: 339 site-reported (SR), 35 CEC-identified, and 71 database (DB)-triggered events based on programmatic identification of a decline in haemoglobin of ≥3 g/dL or in haematocrit by ≥9%; of those, 383/445 (86.1%) met the protocol definition of major bleeding. By multivariable analysis, CEC-confirmed bleeding was an independent predictor of cardiovascular death (hazard ratio [HR] 2.84, 95% confidence interval [CI]: 1.81-4.45, p<0.0001) and all-cause death (HR 2.70, 95% CI: 1.92-3.79, p<0.0001) at three years. Non-CEC-confirmed bleeding was also a predictor of cardiovascular death (HR 3.45, 95% CI: 1.47-8.11, p=0.005) and all-cause death (HR 2.41, 95% CI: 1.11-5.23, p=0.03) at three years.

CONCLUSIONS

In the HORIZONS-AMI trial, adjudication of bleeding via a centralised CEC process resulted in identification of a larger number of events than were SR. All CEC-confirmed bleeding events were independently predictive of three-year cardiovascular and all-cause mortality. The association of non-CEC-confirmed bleeding with mortality merits further investigation.