A comparison of computational algorithms for the Bayesian analysis of clinical trials.

BACKGROUND: Clinical trials are increasingly using Bayesian methods for their design and analysis. Inference in Bayesian trials typically uses simulation-based approaches such as Markov Chain Monte Carlo methods. Markov Chain Monte Carlo has high computational cost and can be complex to implement. The Integrated Nested Laplace Approximations algorithm provides approximate Bayesian inference without the need for computationally complex simulations, making it more efficient than Markov Chain Monte Carlo. The practical properties of Integrated Nested Laplace Approximations compared to Markov Chain Monte Carlo have not been considered for clinical trials. Using data from a published clinical trial, we aim to investigate whether Integrated Nested Laplace Approximations is a feasible and accurate alternative to Markov Chain Monte Carlo and provide practical guidance for trialists interested in Bayesian trial design. METHODS: Data from an international Bayesian multi-platform adaptive trial that compared therapeutic-dose anticoagulation with heparin to usual care in non-critically ill patients hospitalized for COVID-19 were used to fit Bayesian hierarchical generalized mixed models. Integrated Nested Laplace Approximations was compared to two Markov Chain Monte Carlo algorithms, implemented in the software JAGS and stan, using packages available in the statistical software R. Seven outcomes were analysed: organ-support free days (an ordinal outcome), five binary outcomes related to survival and length of hospital stay, and a time-to-event outcome. The posterior distributions for the treatment and sex effects and the variances for the hierarchical effects of age, site and time period were obtained. We summarized these posteriors by calculating the mean, standard deviations and the 95% equitailed credible intervals and presenting the results graphically. The computation time for each algorithm was recorded. RESULTS: The average overlap of the 95% credible interval for the treatment and sex effects estimated using Integrated Nested Laplace Approximations was 96% and 97.6% compared with stan, respectively. The graphical posterior densities for these effects overlapped for all three algorithms. The posterior mean for the variance of the hierarchical effects of age, site and time estimated using Integrated Nested Laplace Approximations are within the 95% credible interval estimated using Markov Chain Monte Carlo but the average overlap of the credible interval is lower, 77%, 85.6% and 91.3%, respectively, for Integrated Nested Laplace Approximations compared to stan. Integrated Nested Laplace Approximations and stan were easily implemented in clear, well-established packages in R, while JAGS required the direct specification of the model. Integrated Nested Laplace Approximations was between 85 and 269 times faster than stan and 26 and 1852 times faster than JAGS. CONCLUSION: Integrated Nested Laplace Approximations could reduce the computational complexity of Bayesian analysis in clinical trials as it is easy to implement in R, substantially faster than Markov Chain Monte Carlo methods implemented in JAGS and stan, and provides near identical approximations to the posterior distributions for the treatment effect. Integrated Nested Laplace Approximations was less accurate when estimating the posterior distribution for the variance of hierarchical effects, particularly for the proportional odds model, and future work should determine if the Integrated Nested Laplace Approximations algorithm can be adjusted to improve this estimation.

Persistence and Adherence to PCSK9 Inhibitor Monoclonal Antibodies Versus Ezetimibe in Real-World Settings.

INTRODUCTION: The cardiovascular disease risk reduction benefits of proprotein convertase subtilisin/kexin type 9 inhibitor monoclonal antibodies (PCSK9i mAb) and ezetimibe are dependent on remaining on treatment and being persistent and adherent. We estimated the percentage of patients on therapy, persistent and adherent at 182 and 365 days among US adults with health insurance who initiated a PCSK9i mAb (n = 16,588) or ezetimibe (n = 83,086) between July 2015 and December 2019. METHODS: Using pharmacy fill claims, being on therapy was defined as having a day of medication supply in the last 60 of 182 and 365 days following treatment initiation, being persistent was defined as not having a gap of 60 days or more between the last day of supply from one prescription fill and the next fill, and being adherent was defined by having medication available to take on ≥ 80% of the 182 and 365 days following treatment initiation. We estimated multivariable-adjusted risk ratios for being persistent and adherent comparing patients initiating PCSK9i mAb versus ezetimibe using Poisson regression. RESULTS: At 182 days following initiation, 80% and 68% were on therapy and 76% and 64% were persistent among patients who initiated a PCSK9i mAb and ezetimibe, respectively. Among patients who were on therapy and persistent at 182 days following initiation, 88% and 81% of those who initiated a PCSK9i mAb and ezetimibe, respectively, were on therapy at 365 days. Among those on therapy and persistent at 182 days following initiation, being persistent and being adherent at 365 days were each more common among PCSK9i mAb versus ezetimibe initiators (persistent: 82% versus 76%, multivariable-adjusted risk ratio 1.07; 95% confidence interval [CI] 1.06-1.08; adherent: 74% versus 71%, multivariable-adjusted risk ratio 1.02; 95% CI 1.01-1.03). CONCLUSIONS: These data suggest approaches to increase persistence and adherence to PCSK9i mAb and ezetimibe should be implemented prior to or within 182 days following treatment initiation.

Medical calculators derived synthetic cohorts: a novel method for generating synthetic patient data.

This study shows that we can use synthetic cohorts created from medical risk calculators to gain insights into how risk estimations, clinical reasoning, data-driven subgrouping, and the confidence in risk calculator scores are connected. When prediction variables aren't evenly distributed in these synthetic cohorts, they can be used to group similar cases together, revealing new insights about how cohorts behave. We also found that the confidence in predictions made by these calculators can vary depending on patient characteristics. This suggests that it might be beneficial to include a "normalized confidence" score in future versions of these calculators for healthcare professionals. We plan to explore this idea further in our upcoming research.

Socioeconomic Disparities in Women's Cardiovascular Health in the United States and Canada.

Cardiovascular disease has been the leading cause of death in the United States and Canada for decades. Although it affects millions of people across a multitude of backgrounds, notable disparities in cardiovascular health are observed among women and become more apparent when accounting for race and socioeconomic status. Although intrinsic sex-specific physiologic differences predispose women to poorer outcomes, social determinants of health (SDOH) and biases at both the individual provider and the larger health care system levels play an equal, if not greater, role. This review examines socioeconomic disparities in women compared with men regarding cardiovascular risk factors, treatments, and outcomes. Although various at-risk subpopulations exist, we highlight the impact of SDOH in specific populations, including patients with disabilities, transgender persons, and South Asian and Indigenous populations. These groups are underrepresented in studies and experience poorer health outcomes owing to structural barriers to care. These findings emphasise the significance of understanding the interplay of different socioeconomic factors and how their stacking can negatively affect women's cardiovascular health. To address these disparities, we propose a multipronged approach to augment culturally sensitive and patient-centred care. This includes increased cardiovascular workforce diversity, inclusion of underrepresented populations into analyses of cardiovascular metrics, and greater utilisation of technology and telemedicine to improve access to health care. Achieving this goal will necessitate active participation from patients, health care administrators, physicians, and policy makers, and is imperative in closing the cardiovascular health gap for women over the coming decades.

Influenza Vaccine Immune Response in Patients With High-Risk Cardiovascular Disease: A Secondary Analysis of the INVESTED Randomized Clinical Trial.

Importance: High-dose trivalent compared with standard-dose quadrivalent influenza vaccine did not significantly reduce all-cause mortality or cardiopulmonary hospitalizations in patients with high-risk cardiovascular disease in the INVESTED trial. Whether humoral immune response to influenza vaccine is associated with clinical outcomes is unknown. Objective: To examine the antibody response to high-dose trivalent compared with standard-dose quadrivalent inactivated influenza vaccine and its associations with clinical outcomes. Design, Setting, and Participants: This secondary analysis is a prespecified analysis of the immune response substudy of the randomized, double-blind, active-controlled INVESTED trial, which was conducted at 157 sites in the United States and Canada over 3 influenza seasons between September 2016 and January 2019. Antibody titers were determined by hemagglutination inhibition assays at randomization and 4 weeks during the 2017-2018 and 2018-2019 seasons. Eligibility criteria included recent acute myocardial infarction or heart failure hospitalization and at least 1 additional risk factor. Data were analyzed from February 2023 to June 2023. Main Outcomes and Measures: Mean antibody titer change, seroprotection (antibody titer level ≥1:40) and seroconversion (≥4-fold increase in titer) at 4 weeks, and the association between seroconversion status and the risk for adverse clinical outcomes. Interventions: High-dose trivalent or standard-dose quadrivalent inactivated influenza vaccine, with revaccination up to 3 seasons. Results: Antibody data were available for 658 of 5260 randomized participants (12.5%; mean [SD] age, 66.2 [11.4] years; 507 male [77.1%], 151 female [22.9%]; 348 with heart failure [52.9%]). High-dose vaccine was associated with an increased magnitude in antibody titers for A/H1N1, A/H3N2, and B-type antigens compared with standard dose. More than 92% of all participants achieved seroprotection for each of the contained antigens, while seroconversion rates were higher in participants who received high-dose vaccine. Seroconversion for any antigen was not associated with the risk for cardiopulmonary hospitalizations or all-cause mortality (hazard ratio, 1.09; 95% CI, 0.79-1.53; P = .59), irrespective of randomized treatment (P = .38 for interaction). Conclusions and Relevance: High-dose vaccine elicited a more robust humoral response in patients with heart failure or prior myocardial infarction enrolled in the INVESTED trial, with no association between seroconversion status and the risk for cardiopulmonary hospitalizations or all-cause mortality. Vaccination to prevent influenza remains critical in high-risk populations. Trial Registration: ClinicalTrials.gov Identifier: NCT02787044.

European Association of Cardio-Thoracic Surgery (EACTS) expert consensus statement on perioperative myocardial infarction after cardiac surgery.

Cardiac surgery may lead to myocardial damage and release of cardiac biomarkers through various mechanisms such as cardiac manipulation, systemic inflammation, myocardial hypoxia, cardioplegic arrest and ischaemia caused by coronary or graft occlusion. Defining perioperative myocardial infarction (PMI) after cardiac surgery presents challenges, and the association between the current PMI definitions and postoperative outcomes remains uncertain. To address these challenges, the European Association of Cardio-Thoracic Surgery (EACTS) facilitated collaboration among a multidisciplinary group to evaluate the existing evidence on the mechanisms, diagnosis and prognostic implications of PMI after cardiac surgery. The review found that the postoperative troponin value thresholds associated with an increased risk of mortality are markedly higher than those proposed by all the current definitions of PMI. Additionally, it was found that large postoperative increases in cardiac biomarkers are prognostically relevant even in absence of additional supportive signs of ischaemia. A new algorithm for PMI detection after cardiac surgery was also proposed, and a consensus was reached within the group that establishing a prognostically relevant definition of PMI is critically needed in the cardiovascular field and that PMI should be included in the primary composite outcome of coronary intervention trials.

Adherence to clinical practice guidelines for pulmonary valve intervention after tetralogy of Fallot repair: A nationwide cohort study.

Objectives: To determine guideline adherence pertaining to pulmonary valve replacement (PVR) referral after tetralogy of Fallot (TOF) repair. Methods: Children and adults with cardiovascular magnetic resonance imaging scans and at least moderate pulmonary regurgitation were prospectively enrolled in the Comprehensive Outcomes Registry Late After TOF Repair (CORRELATE). Individuals with previous PVR were excluded. Patients were classified according to presence (+) versus absence (-) of PVR and presence (+) versus absence (-) of contemporaneous guideline satisfaction. A validated score (specific activity scale [SAS]) classified adult symptom status. Results: In total, 498 participants (57% male, mean age 32 ± 14 years) were enrolled from 14 Canadian centers (2013-2020). Mean follow-up was 3.8 ± 1.8 years. Guideline criteria for PVR were satisfied for the majority (n = 422/498, 85%), although referral for PVR occurred only in a minority (n = 167/498, 34%). At PVR referral, most were asymptomatic (75% in SAS class 1). One participant (0.6%) received PVR without meeting criteria (PVR+/indication-). The remainder (n = 75/498, 15%) did not meet criteria for and did not receive PVR (PVR-/indication-). Abnormal cardiovascular imaging was the most commonly cited indication for PVR (n = 61/123, 50%). The SAS class and ratio of right to left end-diastolic volumes were independent predictors of PVR in a multivariable analysis (hazard ratio, 3.33; 95% confidence interval, 1.92-5.8, P < .0001; hazard ratio, 2.78; 95% confidence interval, 2.18-3.55, P < .0001). Conclusions: Although a majority of patients met guideline criteria for PVR, only a minority were referred for intervention. Abnormal cardiovascular imaging was the most common indication for referral. Further research will be necessary to establish the longer-term clinical impact of varying PVR referral strategies.

Outcomes According to Coronary Revascularization Modality in the ISCHEMIA Trial.

BACKGROUND: In the ISCHEMIA (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches) trial, the risk of ischemic events was similar in patients with stable coronary artery disease treated with an invasive (INV) strategy of angiography and percutaneous coronary intervention (PCI) or surgical (coronary artery bypass grafting [CABG]) coronary revascularization and a conservative (CON) strategy of initial medical therapy. OBJECTIVES: The authors analyzed separately the outcomes of INV patients treated with PCI or CABG. METHODS: Patients without preceding primary outcome events were categorized as INV-PCI or INV-CABG from the time of revascularization. The ISCHEMIA primary outcome (composite of cardiovascular death, protocol-defined myocardial infarction or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest) was used. RESULTS: Among INV-CABG patients, primary outcome events occurred in 84 of 512 (16.4%) at a median follow-up of 2.85 years; 48 events (57.1%) occurred within 30 days after CABG, including 40 procedural MIs. Among INV-PCI patients, primary outcome events occurred in 147 of 1,500 (9.8%) at median follow-up of 2.94 years; 31 of which (21.1%) occurred within 30 days after PCI, including 24 procedural MIs. In comparison, 352 of 2,591 CON patients (13.6%) had primary outcome events at a median follow-up of 3.2 years, 22 of which (6.3%) occurred within 30 days of randomization. The adjusted primary outcome risks were higher after both CABG and PCI within 30 days (HR: 16.25 [95% CI: 11.44-23.07] and HR: 2.99 [95% CI: 1.97-4.53]) and lower thereafter (0.63 [95% CI: 0.44-0.89] and 0.66 [95% CI: 0.53-0.82]). CONCLUSIONS: In ISCHEMIA, early revascularization by PCI and CABG was associated with higher early risks and lower long-term risks of cardiovascular events compared with CON. The early risk was greatest after CABG, owing to protocol-defined procedural MIs.

Development and Validation of the CANHEART Population-Based Laboratory Prediction Models for Atherosclerotic Cardiovascular Disease.

BACKGROUND: Prediction of atherosclerotic cardiovascular disease (ASCVD) in primary prevention assessments exclusively with laboratory results may facilitate automated risk reporting and improve uptake of preventive therapies. OBJECTIVE: To develop and validate sex-specific prediction models for ASCVD using age and routine laboratory tests and compare their performance with that of the pooled cohort equations (PCEs). DESIGN: Derivation and validation of the CANHEART (Cardiovascular Health in Ambulatory Care Research Team) Lab Models. SETTING: Population-based cohort study in Ontario, Canada. PARTICIPANTS: A derivation and internal validation cohort of adults aged 40 to 75 years without cardiovascular disease from April 2009 to December 2015; an external validation cohort of primary care patients from January 2010 to December 2014. MEASUREMENTS: Age and laboratory predictors measured in the outpatient setting included serum total cholesterol, high-density lipoprotein cholesterol, triglycerides, hemoglobin, mean corpuscular volume, platelets, leukocytes, estimated glomerular filtration rate, and glucose. The ASCVD outcomes were defined as myocardial infarction, stroke, and death from ischemic heart or cerebrovascular disease within 5 years. RESULTS: Sex-specific models were developed and internally validated in 2 160 497 women and 1 833 147 men. They were well calibrated, with relative differences less than 1% between mean predicted and observed risk for both sexes. The c-statistic was 0.77 in women and 0.71 in men. External validation in 31 697 primary care patients showed a relative difference less than 14% and an absolute difference less than 0.3 percentage points in mean predicted and observed risks for both sexes. The c-statistics for the laboratory models were 0.72 for both sexes and were not statistically significantly different from those for the PCEs in women (change in c-statistic, -0.01 [95% CI, -0.03 to 0.01]) or men (change in c-statistic, -0.01 [CI, -0.04 to 0.02]). LIMITATION: Medication use was not available at the population level. CONCLUSION: The CANHEART Lab Models predict ASCVD with similar accuracy to more complex models, such as the PCEs. PRIMARY FUNDING SOURCE: Canadian Institutes of Health Research.

Digital Tool-Assisted Hospitalization Detection in the Tailored Antiplatelet Initiation to Lessen Outcomes due to Decreased Clopidogrel Response After Percutaneous Coronary Intervention Study Compared to Traditional Site-Coordinator Ascertainment: Intervention Study.

BACKGROUND: Accurate, timely ascertainment of clinical end points, particularly hospitalizations, is crucial for clinical trials. The Tailored Antiplatelet Initiation to Lessen Outcomes Due to Decreased Clopidogrel Response after Percutaneous Coronary Intervention (TAILOR-PCI) Digital Study extended the main TAILOR-PCI trial's follow-up to 2 years, using a smartphone-based research app featuring geofencing-triggered surveys and routine monthly mobile phone surveys to detect cardiovascular (CV) hospitalizations. This pilot study compared these digital tools to conventional site-coordinator ascertainment of CV hospitalizations. OBJECTIVE: The objectives were to evaluate geofencing-triggered notifications and routine monthly mobile phone surveys' performance in detecting CV hospitalizations compared to telephone visits and health record reviews by study coordinators at each site. METHODS: US and Canadian participants from the TAILOR-PCI Digital Follow-Up Study were invited to download the Eureka Research Platform mobile app, opting in for location tracking using geofencing, triggering a smartphone-based survey if near a hospital for ≥4 hours. Participants were sent monthly notifications for CV hospitalization surveys. RESULTS: From 85 participants who consented to the Digital Study, downloaded the mobile app, and had not previously completed their final follow-up visit, 73 (85.8%) initially opted in and consented to geofencing. There were 9 CV hospitalizations ascertained by study coordinators among 5 patients, whereas 8 out of 9 (88.9%) were detected by routine monthly hospitalization surveys. One CV hospitalization went undetected by the survey as it occurred within two weeks of the previous event, and the survey only allowed reporting of a single hospitalization. Among these, 3 were also detected by the geofencing algorithm, but 6 out of 9 (66.7%) were missed by geofencing: 1 occurred in a participant who never consented to geofencing, while 5 hospitalizations occurred among participants who had subsequently turned off geofencing prior to their hospitalization. Geofencing-detected hospitalizations were ascertained within a median of 2 (IQR 1-3) days, monthly surveys within 11 (IQR 6.5-25) days, and site coordinator methods within 38 (IQR 9-105) days. The geofencing algorithm triggered 245 notifications among 39 participants, with 128 (52.2%) from true hospital presence and 117 (47.8%) from nonhospital health care facility visits. Additional geofencing iterative improvements to reduce hospital misidentification were made to the algorithm at months 7 and 12, elevating the rate of true alerts from 35.4% (55 true alerts/155 total alerts before month 7) to 78.7% (59 true alerts/75 total alerts in months 7-12) and ultimately to 93.3% (14 true alerts/5 total alerts in months 13-21), respectively. CONCLUSIONS: The monthly digital survey detected most CV hospitalizations, while the geofencing survey enabled earlier detection but did not offer incremental value beyond traditional tools. Digital tools could potentially reduce the burden on study coordinators in ascertaining CV hospitalizations. The advantages of timely reporting via geofencing should be weighed against the issue of false notifications, which can be mitigated through algorithmic refinements.

Effect of therapeutic-dose heparin on severe acute kidney injury and death in noncritically ill patients hospitalized for COVID-19: a prespecified secondary analysis of the ACTIV4a and ATTACC randomized trial.

Background: Acute kidney injury (AKI) in patients with COVID-19 is partly mediated by thromboinflammation. In noncritically ill patients with COVID-19, therapeutic-dose anticoagulation with heparin increased the probability of survival to hospital discharge with reduced use of cardiovascular or respiratory organ support. Objectives: We investigated whether therapeutic-dose heparin reduces the incidence of AKI or death in noncritically ill patients hospitalized for COVID-19. Methods: We report a prespecified secondary analysis of the ACTIV4a and ATTACC open-label, multiplatform randomized trial of therapeutic-dose heparin vs usual-care pharmacologic thromboprophylaxis on the incidence of severe AKI (≥2-fold increase in serum creatinine or initiation of kidney replacement therapy (KDIGO stage 2 or 3) or all-cause mortality in noncritically ill patients hospitalized for COVID-19. Bayesian statistical models were adjusted for age, sex, D-dimer, enrollment period, country, site, and platform. Results: Among 1922 enrolled, 23 were excluded due to pre-existing end stage kidney disease and 205 were missing baseline or follow-up creatinine measurements. Severe AKI or death occurred in 4.4% participants assigned to therapeutic-dose heparin and 5.5% assigned to thromboprophylaxis (adjusted relative risk [aRR]: 0.72; 95% credible interval (CrI): 0.47, 1.10); the posterior probability of superiority for therapeutic-dose heparin (relative risk < 1.0) was 93.6%. Therapeutic-dose heparin was associated with a 97.7% probability of superiority to reduce the composite of stage 3 AKI or death (3.1% vs 4.6%; aRR: 0.64; 95% CrI: 0.40, 0.99) compared to thromboprophylaxis. Conclusion: Therapeutic-dose heparin was associated with a high probability of superiority to reduce the incidence of in-hospital severe AKI or death in patients hospitalized for COVID-19.

Temporal Association Among Influenza-Like Illness, Cardiovascular Events, and Vaccine Dose in Patients With High-Risk Cardiovascular Disease: Secondary Analysis of a Randomized Clinical Trial.

Importance: Influenza-like illness (ILI) activity has been associated with increased risk of cardiopulmonary (CP) events during the influenza season. High-dose trivalent influenza vaccine was not superior to standard-dose quadrivalent vaccine for reducing these events in patients with high-risk cardiovascular (CV) disease in the Influenza Vaccine to Effectively Stop Cardio Thoracic Events and Decompensated Heart Failure (INVESTED) trial. Objective: To evaluate whether high-dose trivalent influenza vaccination is associated with benefit over standard-dose quadrivalent vaccination in reducing CP events during periods of high, local influenza activity. Design, Setting, and Participants: This study was a prespecified secondary analysis of INVESTED, a multicenter, double-blind, active comparator randomized clinical trial conducted over 3 consecutive influenza seasons from September 2016 to July 2019. Follow-up was completed in July 2019, and data were analyzed from September 21, 2016, to July 31, 2019. Weekly Centers for Disease Control and Prevention (CDC)-reported, state-level ILI activity was ascertained to assess the weekly odds of the primary outcome. The study population included 3094 patients with high-risk CV disease from participating centers in the US. Intervention: Participants were randomized to high-dose trivalent or standard-dose quadrivalent influenza vaccine and revaccinated for up to 3 seasons. Main Outcomes and Measures: The primary outcome was the time to composite of all-cause death or CP hospitalization within each season. Additional measures included weekly CDC-reported ILI activity data by state. Results: Among 3094 participants (mean [SD] age, 65 [12] years; 2309 male [75%]), we analyzed 129 285 person-weeks of enrollment, including 1396 composite primary outcome events (1278 CP hospitalization, 118 deaths). A 1% ILI increase in the prior week was associated with an increased risk in the primary outcome (odds ratio [OR], 1.14; 95% CI, 1.07-1.21; P < .001), CP hospitalization (OR, 1.13; 95% CI, 1.06-1.21; P < .001), and CV hospitalization (OR, 1.12; 95% CI, 1.04-1.19; P = .001), after adjusting for state, demographic characteristics, enrollment strata, and CV risk factors. Increased ILI activity was not associated with all-cause death (OR, 1.00; 95% CI, 0.88-1.13; P > .99). High-dose compared with standard-dose vaccine did not significantly reduce the primary outcome, even when the analysis was restricted to weeks of high ILI activity (OR, 0.88; 95% CI, 0.65-1.20; P = .43). Traditionally warmer months in the US were associated with lower CV risk independent of local ILI activity. Conclusions and Relevance: In this secondary analysis of a randomized clinical trial, ILI activity was temporally associated with increased CP events in patients with high-risk CV disease, and a higher influenza vaccine dose did not significantly reduce temporal CV risk. Other seasonal factors may play a role in the coincident high rates of ILI and CV events. Trial Registration: ClinicalTrials.gov Identifier: NCT02787044.

STICH3C: Rationale and Study Protocol.

BACKGROUND: Coronary artery bypass grafting (CABG) is the recommended mode of revascularization in patients with ischemic left ventricular dysfunction (iLVSD) and multivessel disease. However, contemporary percutaneous coronary intervention (PCI) outcomes have improved with the integration of novel technologies and refinement of revascularization strategies, and PCI is often used in clinical practice in this population. There is a lack of evidence from randomized trials comparing contemporary state-of-the-art PCI versus CABG for the treatment of iLVSD and multivessel disease. This was the impetus for the STICH3C trial (Canadian CABG or PCI in Patients With Ischemic Cardiomyopathy), described here. METHODS: The STICH3C trial is a prospective, unblinded, international, multicenter trial with an expected sample size of 754 participants from ≈45 centers. Patients with multivessel/left main coronary artery disease and iLVSD with left ventricular ejection fraction ≤40% considered by the local Heart Team appropriate for and amenable to revascularization by both modes of revascularization will be randomized in a 1:1 ratio to state-of-the-art PCI or CABG. RESULTS: The primary end point is the composite of death from any cause, stroke, spontaneous myocardial infarction, urgent repeat revascularization, or heart failure readmission, summarized as a time-to-event outcome. The key hierarchical end point is time to death and frequency of hospitalizations for heart failure. The key safety outcome is a composite of major adverse events. Disease-specific quality-of-life and health economics measures will be compared between groups. Participants will be followed for a median of 5 years, with a minimum follow-up of 4 years. CONCLUSIONS: STICH3C will directly inform patients, clinicians, and international practice guidelines about the efficacy and safety of CABG versus PCI in patients with iLVSD. The results will provide novel and broad evidence, including clinical events, health status, and economic assessments, to guide care for patients with iLVSD and severe coronary artery disease. REGISTRATION: URL: https://clinicaltrials.gov/; Unique identifier: NCT05427370.

Dealing With Nonproportional Hazards in Coronary Revascularisation Studies.

The Cox proportional hazards model is one of the most popular statistical tools to model time to event outcomes without the need for specifying the hazards or survival time distributions. The Cox model requires that the ratio of the hazards of the occurrence of the outcome for any 2 individuals remains constant during the entire follow-up. Studies comparing coronary revascularisation strategies, however, might be prone to violations of proportionality by the crossing of the hazard functions over time. Early increases in the risk of cardiovascular outcomes are commonly observed when comparing coronary artery bypass grafting vs percutaneous coronary intervention, whereas decreased risk might be observed later during the follow-up. The same is valid for comparisons between invasive vs conservative coronary revascularisation strategies. In these situations, the statistical power of the Cox model is reduced, and hazard ratios might not be an informative summary measure of treatment effect. In this article, we discuss methods to identify and account for nonproportionality. We illustrate the use of these methods in a case study based on reconstructed data from a coronary revascularisation clinical trial. And finally, we review the cardiovascular literature to estimate how the proportionality assumption has been reported in coronary revascularisation studies recently.

Incident CHD and ischemic stroke associated with lipoprotein(a) by levels of Factor VIII and inflammation.

BACKGROUND: Inflammation and coagulation may contribute to the increased risk for atherosclerotic cardiovascular disease (ASCVD) associated with high lipoprotein(a). The association of lipoprotein(a) with ASCVD is stronger in individuals with high versus low high-sensitivity C-reactive protein (hs-CRP), a marker of inflammation. OBJECTIVES: Determine the association of lipoprotein(a) with incident ASCVD by levels of coagulation Factor VIII controlling for hs-CRP. METHODS: We analyzed data from 6,495 men and women 45 to 84 years of age in the Multi-Ethnic Study of Atherosclerosis (MESA) without prevalent ASCVD at baseline (2000-2002). Lipoprotein(a) mass concentration, Factor VIII coagulant activity, and hs-CRP were measured at baseline and categorized as high or low (≥75th or <75th percentile of the distribution). Participants were followed for incident coronary heart disease (CHD) and ischemic stroke through 2015. RESULTS: Over a median follow-up of 13.9 years, there were 390 CHD and 247 ischemic stroke events. The hazard ratio (95%CI) for CHD associated with high lipoprotein(a) (≥40.1 versus <40.1 mg/dL) including adjustment for hs-CRP among participants with low and high Factor VIII was 1.07 (0.80-1.44) and 2.00 (1.33-3.01), respectively (p-value for interaction 0.016). The hazard ratio (95%CI) for CHD associated with high lipoprotein(a) including adjustment for Factor VIII was 1.16 (0.87-1.54) and 2.00 (1.29-3.09) among participants with low and high hs-CRP, respectively (p-value for interaction 0.042). Lp(a) was not associated with ischemic stroke regardless of Factor VIII or hs-CRP levels. CONCLUSION: High lipoprotein(a) is a risk factor for CHD in adults with high levels of hemostatic or inflammatory markers.