Percutaneous Coronary Revascularization Strategies After Myocardial Infarction: A Systematic Review and Network Meta-Analysis.

BACKGROUND: Complete revascularization with percutaneous coronary intervention improves outcomes compared with culprit revascularization following myocardial infarction (MI) with multivessel coronary artery disease. An all-cause mortality reduction has never been demonstrated. Debate also remains regarding the optimal timing of complete revascularization (immediate or staged), and method of evaluation of nonculprit lesions (physiology or angiography). OBJECTIVES: This study aims to perform an updated systematic review with frequentist and Bayesian network meta-analyses including the totality of randomized data investigating revascularization strategies in patients presenting with MI and multivessel coronary artery disease. METHODS: The primary comparison tested complete vs culprit revascularization. Timing and methods of achieving complete revascularization were assessed. The prespecified primary outcome was all-cause mortality. Outcomes were expressed as relative risk (RR) (95% CI). RESULTS: Twenty-four eligible trials randomized 16,371 patients (weighted mean follow-up: 26.4 months). Compared with culprit revascularization, complete revascularization reduced all-cause mortality in patients with any MI (RR: 0.85; 95% CI: 0.74-0.99; P = 0.04). Cardiovascular mortality, MI, major adverse cardiac events and repeat revascularization were also significantly reduced. In patients presenting with ST-segment elevation myocardial infarction, the point estimate for all-cause mortality with complete revascularization was RR: 0.91 (95% CI: 0.78-1.05; P = 0.18). Rates of stent thrombosis, major bleeding, and acute kidney injury were similar. Immediate complete revascularization ranked higher than staged complete revascularization for all endpoints. CONCLUSIONS: Complete revascularization following MI reduces all-cause mortality, cardiovascular mortality, MI, major adverse cardiac events, and repeat revascularization. There may be benefits to immediate complete revascularization, but additional head-to-head trials are needed.

Genetically proxied low-density lipoprotein cholesterol lowering via PCSK9-inhibitor drug targets and risk of congenital malformations.

AIMS: Current guidelines advise against the use of lipid-lowering drugs during pregnancy. This is based only on previous observational evidence demonstrating an association between statin use and congenital malformations, which is increasingly controversial. In the absence of clinical trial data, we aimed to use drug-target Mendelian randomization to model the potential impact of fetal LDL-lowering, overall and through PCSK9 drug targets, on congenital malformations. METHODS AND RESULTS: Instrumental variants influencing LDL levels overall and through PCSK9-inhibitor drug targets were extracted from genome-wide association study (GWAS) summary data for LDL on 1 320 016 individuals. Instrumental variants influencing circulating PCSK9 levels (pQTLs) and liver PCSK9 gene expression levels (eQTLs) were extracted, respectively, from a GWAS on 10 186 individuals and from the genotype-tissue expression project. Gene-outcome association data was extracted from the 7th release of GWAS summary data on the FinnGen cohort (n = 342 499) for eight categories of congenital malformations affecting multiple systems. Genetically proxied LDL-lowering through PCSK9 was associated with higher odds of malformations affecting multiple systems [OR 2.70, 95% confidence interval (CI) 1.30-5.63, P = 0.018], the skin (OR 2.23, 95% CI 1.33-3.75, P = 0.007), and the vertebral, anorectal, cardiovascular, tracheo-esophageal, renal, and limb association (VACTERL) (OR 1.51, 95% CI 1.16-1.96, P = 0.007). An association was also found with obstructive defects of the renal pelvis and ureter, but this association was suggestive of horizontal pleiotropy. Lower PCSK9 pQTLs were associated with the same congenital malformations. CONCLUSION: These data provide genetic evidence supporting current manufacturer advice to avoid the use of PCSK9 inhibitors during pregnancy.

Using genetic techniques to mimic the effects of PCSK9-inhibitors, a group of lipid-lowering medications, this study provides evidence to support recommendations to avoid the use of these medications in pregnancy due to potential risk of multiple malformations in the newborn.This study provides genetic evidence to support potential associations of PCSK9-inhibitor medications with newborn malformations affecting multiple organ systems, the skin, and a cluster of structural defects simultaneously affecting the spine, anus/rectum, heart, throat, kidneys, arms and legs.There was also weaker evidence of an association of PCSK9-inhibitor medications with newborn malformations resulting in blockages of the kidneys and urine system, though the evidence was less certain for these than for the other malformations.

Placebo Control and Blinding in Randomized Trials of Procedural Interventions: A Systematic Review and Meta-Regression.

Importance: Unlike medications, procedural interventions are rarely trialed against placebo prior to becoming accepted in clinical practice. When placebo-controlled trials are eventually conducted, procedural interventions may be less effective than previously believed. Objective: To investigate the importance of including a placebo arm in trials of surgical and interventional procedures by comparing effect sizes from trials of the same procedure that do and do not include a placebo arm. Data Sources: Searches of MEDLINE and Embase identified all placebo-controlled trials for procedural interventions in any specialty of medicine and surgery from inception to March 31, 2019. A secondary search identified randomized clinical trials assessing the same intervention, condition, and end point but without a placebo arm for paired comparison. Study Selection: Placebo-controlled trials of anatomically site-specific procedures requiring skin incision or endoscopic techniques were eligible for inclusion; these were then matched to trials without placebo control that fell within prespecified limits of heterogeneity. Data Extraction and Synthesis: Random-effects meta-regression, with placebo and blinding as a fixed effect and intervention and end point grouping as random effects, was used to calculate the impact of placebo control for each end point. Data were analyzed from March 2019 to March 2020. Main Outcomes and Measures: End points were examined in prespecified subgroups: patient-reported or health care professional-assessed outcomes, quality of life, pain, blood pressure, exercise-related outcomes, recurrent bleeding, and all-cause mortality. Results: Ninety-seven end points were matched from 72 blinded, placebo-controlled trials (hereafter, blinded) and 55 unblinded trials without placebo control (hereafter, unblinded), including 111 500 individual patient end points. Unblinded trials had larger standardized effect sizes than blinded trials for exercise-related outcomes (standardized mean difference [SMD], 0.59; 95% CI, 0.29 to 0.89; P < .001) and quality-of-life (SMD, 0.32; 95% CI, 0.11 to 0.53; P = .003) and health care professional-assessed end points (SMD, 0.40; 95% CI, 0.18 to 0.61; P < .001). The placebo effect accounted for 88.1%, 55.2%, and 61.3% of the observed unblinded effect size for these end points, respectively. There was no significant difference between unblinded and blinded trials for patient-reported end points (SMD, 0.31; 95% CI, -0.02 to 0.64; P = .07), blood pressure (SMD, 0.26; 95% CI, -0.10 to 0.62; P = .15), all-cause mortality (odds ratio [OR], 0.23; 95% CI, -0.26 to 0.72; P = .36), pain (SMD, 0.03; 95% CI, -0.52 to 0.57; P = .91), or recurrent bleeding events (OR, -0.12; 95% CI, -1.11 to 0.88; P = .88). Conclusions and Relevance: The magnitude of the placebo effect found in this systematic review and meta-regression was dependent on the end point. Placebo control in trials of procedural interventions had the greatest impact on exercise-related, quality-of-life, and health care professional-assessed end points. Randomized clinical trials of procedural interventions may consider placebo control accordingly.

Intravascular Imaging-Guided Versus Angiography-Guided Percutaneous Coronary Intervention: A Systematic Review and Meta-Analysis of Randomized Trials.

BACKGROUND: Despite the initial evidence supporting the utility of intravascular imaging to guide percutaneous coronary intervention (PCI), adoption remains low. Recent new trial data have become available. An updated study-level meta-analysis comparing intravascular imaging to angiography to guide PCI was performed. This study aimed to evaluate the clinical outcomes of intravascular imaging-guided PCI compared with angiography-guided PCI. METHODS AND RESULTS: A random-effects meta-analysis was performed on the basis of the intention-to-treat principle. The primary outcomes were major adverse cardiac events, cardiac death, and all-cause death. Mixed-effects meta-regression was performed to investigate the impact of complex PCI on the primary outcomes. A total of 16 trials with 7814 patients were included. The weighted mean follow-up duration was 28.8 months. Intravascular imaging led to a lower risk of major adverse cardiac events (relative risk [RR], 0.67 [95% CI, 0.55-0.82]; P<0.001), cardiac death (RR, 0.49 [95% CI, 0.34-0.71]; P<0.001), stent thrombosis (RR, 0.63 [95% CI, 0.40-0.99]; P=0.046), target-lesion revascularization (RR, 0.67 [95% CI, 0.49-0.91]; P=0.01), and target-vessel revascularization (RR, 0.60 [95% CI, 0.45-0.80]; P<0.001). In complex lesion subsets, the point estimate for imaging-guided PCI compared with angiography-guided PCI for all-cause death was a RR of 0.75 (95% CI, 0.55-1.02; P=0.07). CONCLUSIONS: In patients undergoing PCI, intravascular imaging is associated with reductions in major adverse cardiac events, cardiac death, stent thrombosis, target-lesion revascularization, and target-vessel revascularization. The magnitude of benefit is large and consistent across all included studies. There may also be benefits in all-cause death, particularly in complex lesion subsets. These results support the use of intravascular imaging as standard of care and updates of clinical guidelines.

Catheter Ablation for Ventricular Tachycardia After MI: A Reconstructed Individual Patient Data Meta-analysis of Randomised Controlled Trials.

Background: The prognostic impact of ventricular tachycardia (VT) catheter ablation is an important outstanding research question. We undertook a reconstructed individual patient data meta-analysis of randomised controlled trials comparing ablation to medical therapy in patients developing VT after MI. Methods: We systematically identified all trials comparing catheter ablation to medical therapy in patients with VT and prior MI. The prespecified primary endpoint was reconstructed individual patient assessment of all-cause mortality. Prespecified secondary endpoints included trial-level assessment of all-cause mortality, VT recurrence or defibrillator shocks and all-cause hospitalisations. Prespecified subgroup analysis was performed for ablation approaches involving only substrate modification without VT activation mapping. Sensitivity analyses were performed depending on the proportion of patients with prior MI included. Results: Eight trials, recruiting a total of 874 patients, were included. Of these 874 patients, 430 were randomised to catheter ablation and 444 were randomised to medical therapy. Catheter ablation reduced all-cause mortality compared with medical therapy when synthesising individual patient data (HR 0.63; 95% CI [0.41-0.96]; p=0.03), but not in trial-level analysis (RR 0.91; 95% CI [0.67-1.23]; p=0.53; I2=0%). Catheter ablation significantly reduced VT recurrence, defibrillator shocks and hospitalisations compared with medical therapy. Sensitivity analyses were consistent with the primary analyses. Conclusion: In patients with postinfarct VT, catheter ablation reduces mortality.