Background: Randomized trials of therapies that primarily lowered triglycerides have not consistently shown reductions in cardiovascular events. Methods: We performed a systematic review and trial-level meta-regression analysis of 3 classes of lipid-lowering therapies that reduce triglycerides to a greater extent than they do low-density lipoprotein cholesterol (LDL-C): fibrates, niacin, and marine-derived omega-3 fatty acids. Key inclusion criteria were a randomized controlled trial that reported major vascular events. We also incorporated data from a previous meta-regression of 25 statin trials. The main outcome measure was the risk ratio (RR) for major vascular events associated with absolute reductions in lipid parameters. Results: A total of 197 270 participants from 24 trials of nonstatin therapy with 25 218 major vascular events and 177 088 participants from 25 trials of statin therapy with 20 962 major vascular events were included, for a total of 374 358 patients and 46 180 major cardiovascular events. Starting with non–high-density lipoprotein cholesterol, a surrogate for very-low-density lipoproteins and low-density lipoproteins, the RR per 1-mmol/L reduction in non–high-density lipoprotein cholesterol was 0.79 (95% CI, 0.76–0.82; P <0.0001; 0.78 per 40 mg/dL). In a multivariable meta-regression model that included terms for both LDL-C and triglyceride (surrogates for low-density lipoproteins and very-low-density lipoproteins, respectively), the RR was 0.80 (95% CI, 0.76–0.85; P <0.0001) per 1-mmol/L (0.79 per 40 mg/dL) reduction in LDL-C and 0.84 (95% CI, 0.75–0.94; P =0.0026) per 1-mmol/L (0.92 per 40 mg/dL) reduction in triglycerides. REDUCE-IT (Reduction of Cardiovascular Events With Icosapent Ethyl–Intervention Trial) was a significant outlier and strongly influential trial in the meta-regression. When removed, the RRs became 0.79 (95% CI, 0.76–0.83; P <0.0001) per 1-mmol/L (0.78 per 40 mg/dL) reduction in LDL-C and 0.91 (95% CI, 0.81–1.006; P =0.06) per 1-mmol/L (0.96 per 40 mg/dL) reduction in triglycerides. In regard to omega-3 dose, each 1 g/d eicosapentaenoic acid administered was associated with a 7% relative risk reduction in major vascular events (RR, 0.93 [95% CI, 0.91–0.95]; P <0.0001), whereas there was no significant association between the dose of docosahexaenoic acid and the relative risk reduction in major vascular events (RR 0.96 [95% CI, 0.89–1.03]). Conclusions: In randomized controlled trials, triglyceride lowering is associated with a lower risk of major vascular events, even after adjustment for LDL-C lowering, although the effect is less than that for LDL-C and attenuated when REDUCE-IT is excluded. Furthermore, the benefits of marine-derived omega-3 fatty acids, particularly high-dose eicosapentaenoic acid, appear to exceed their lipid-lowering effects.

The discovery of genetic loci associated with complex diseases has outpaced the elucidation of mechanisms of disease pathogenesis. Here we conducted a genome-wide association study (GWAS) for coronary artery disease (CAD) comprising 181,522 cases among 1,165,690 participants of predominantly European ancestry. We detected 241 associations, including 30 new loci. Cross-ancestry meta-analysis with a Japanese GWAS yielded 38 additional new loci. We prioritized likely causal variants using functionally informed fine-mapping, yielding 42 associations with less than five variants in the 95% credible set. Similarity-based clustering suggested roles for early developmental processes, cell cycle signaling and vascular cell migration and proliferation in the pathogenesis of CAD. We prioritized 220 candidate causal genes, combining eight complementary approaches, including 123 supported by three or more approaches. Using CRISPR–Cas9, we experimentally validated the effect of an enhancer in MYO9B, which appears to mediate CAD risk by regulating vascular cell motility. Our analysis identifies and systematically characterizes >250 risk loci for CAD to inform experimental interrogation of putative causal mechanisms for CAD.

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Background: The ability of a genetic risk score to predict risk in established cardiovascular disease and identify individuals who derive greater benefit from PCSK9 (proprotein convertase subtilisin/kexin type 9) inhibition has not been established. Methods: We studied 14 298 patients with atherosclerotic cardiovascular disease from the FOURIER trial (Further Cardiovascular Outcomes Researh With PCSK9 Inhibition in Subjects With Elevated Risk). A 27–single-nucleotide polymorphism genetic risk score defined low (quintile 1), intermediate (quintiles 2–4), and high (quintile 5) genetic risk. Patients were also categorized by major atherosclerotic risk factors including diabetes mellitus, hypertension, low-density lipoprotein cholesterol ≥100 mg/dl, and smoking; multiple (≥2) risk factors was considered high clinical risk. Outcomes consisted of major coronary events (coronary heart death, myocardial infarction, or coronary revascularization) and major vascular events (major coronary events and ischemic stroke). Median follow-up was 2.3 years. Results: After we adjusted for clinical factors, the genetic risk score was associated with risk for both major vascular events ( P trend =0.005) and major coronary events ( P trend <0.0001). Individuals with intermediate and high genetic risk scores had 1.23- and 1.65-fold increased hazard for major coronary events, respectively. Elevated genetic risk was additive to major atherosclerotic risk factors and identified patients more likely to benefit from evolocumab. There was no benefit for major vascular events in patients without multiple clinical risk factors or high genetic risk (hazard ratio [HR], 1.02; absolute risk reduction [ARR], −0.2%, P =0.86). In contrast, there was a 13% relative risk reduction (HR, 0.87 [0.75–0.998], P =0.047) and a 1.4% ARR in patients with multiple clinical risk factors but without high genetic risk and a 31% relative risk reduction (HR, 0.69 [0.55–0.86], P =0.0012), and 4.0% ARR in patients with high genetic risk, irrespective of clinical risk ( P trend for HR=0.017, ARR P trend =0.004). Patients with high genetic risk who received evolocumab had event rates similar to patients with a low burden of both genetic and clinical risk. Conclusion: Patients without multiple clinical risk factors or high genetic risk had a low event rate and did not appear to derive benefit from evolocumab over 2.3 years. Conversely, patients with multiple clinical risk factors but without high genetic risk had intermediate risk and intermediate risk reduction. Patients with high genetic risk, regardless of clinical risk, had a high event rate and derived the greatest relative and absolute benefit from evolocumab, which mitigated this risk.

Aims Childhood-onset hypertrophic cardiomyopathy (HCM) is far less common than adult-onset disease, thus natural history is not well characterized. We aim to describe the characteristics and outcomes of childhood-onset HCM. Methods and results We performed an observational cohort study of 7677 HCM patients from the Sarcomeric Human Cardiomyopathy Registry (SHaRe). Hypertrophic cardiomyopathy patients were stratified by age at diagnosis [&lt;1 year (infancy), 1–18 years (childhood), &gt;18 years (adulthood)] and assessed for composite endpoints reflecting heart failure (HF), life-threatening ventricular arrhythmias, atrial fibrillation (AF), and an overall composite that also included stroke and death. Stratifying by age of diagnosis, 184 (2.4%) patients were diagnosed in infancy; 1128 (14.7%) in childhood; and 6365 (82.9%) in adulthood. Childhood-onset HCM patients had an ∼2%/year event rate for the overall composite endpoint, with ventricular arrhythmias representing the most common event in the 1st decade following baseline visit, but HF and AF becoming more common by the end of the 2nd decade. Sarcomeric variants were more common in childhood-onset HCM (63%) and carried a worse prognosis than non-sarcomeric disease, including a greater than two-fold increased risk of HF [HRadj 2.39 (1.36–4.20), P = 0.003] and 67% increased risk of the overall composite outcome [HRadj 1.67 (1.16–2.41), P = 0.006]. When compared with adult-onset HCM, childhood-onset was 36% more likely to develop life-threatening ventricular arrhythmias [HRadj 1.36 (1.03–1.80)] and twice as likely to require transplant or ventricular assist device [HRadj 1.99 (1.23–3.23)]. Conclusion Patients with childhood-onset HCM are more likely to have sarcomeric disease, carry a higher risk of life-threatening ventricular arrythmias, and have greater need for advanced HF therapies. These findings provide insight into the natural history of disease and can help inform clinical risk stratification.

Background: Genetic loss-of-function variants in ANGPTL3 are associated with lower levels of plasma lipids. Vupanorsen is a hepatically targeted antisense oligonucleotide that inhibits Angiopoietin-like 3 (ANGPTL3) protein synthesis. Methods: Adults with non-high-density lipoprotein cholesterol (non-HDL-C) ≥100 mg/dL and triglycerides 150 to 500 mg/dL on statin therapy were randomized in a double-blind fashion to placebo or 1 of 7 vupanorsen dose regimens (80, 120, or 160 mg SC every 4 weeks, or 60, 80, 120, or 160 mg SC every 2 weeks). The primary end point was placebo-adjusted percentage change from baseline in non-HDL-C at 24 weeks. Secondary end points included placebo-adjusted percentage changes from baseline in triglycerides, low-density lipoprotein cholesterol (LDL-C), apolipoprotein B (ApoB), and ANGPTL3. Results: Two hundred eighty-six subjects were randomized: 44 to placebo and 242 to vupanorsen. The median age was 64 (interquartile range, 58-69) years, 44% were female, the median non-HDL-C was 132.4 (interquartile range, 118.0-154.1) mg/dL, and the median triglycerides were 216.2 (interquartile range, 181.4-270.4) mg/dL. Vupanorsen resulted in significant decreases from baseline over placebo in non-HDL-C ranging from 22.0% in the 60 mg every 2 weeks arm to 27.7% in the 80 mg every 2 weeks arm (all P <0.001 for all doses). There were dose-dependent reductions in triglycerides that ranged from 41.3% to 56.8% (all P <0.001). The effects on LDL-C and ApoB were more modest (7.9%-16.0% and 6.0%-15.1%, respectively) and without a clear dose-response relationship‚ and only the higher reductions achieved statistical significance. ANGPTL3 levels were decreased in a dose-dependent manner by 69.9% to 95.2% (all P <0.001). There were no confirmed instances of significant decline in renal function or platelet count with vupanorsen. Injection site reactions and >3x elevations of alanine aminotransferase or aspartate aminotransferase were more common at higher total monthly doses (up to 33.3% and 44.4%, respectively), and there was a dose-dependent increase in hepatic fat fraction (up to 76%). Conclusions: Vupanorsen administered at monthly equivalent doses from 80 to 320 mg significantly reduced non-HDL-C and additional lipid parameters. Injection site reactions and liver enzyme elevations were more frequent at higher doses, and there was a dose-dependent increase in hepatic f at fraction.

Rapid progress of the discovery of genetic loci associated with common, complex diseases has outpaced the elucidation of mechanisms pertinent to disease pathogenesis. To address relevant barriers for coronary artery disease (CAD), we combined genetic discovery analyses with downstream characterization of likely causal variants, genes, and biological pathways. Specifically, we conducted a genome-wide association study (GWAS) comprising 181,522 cases of CAD among 1,165,690 participants. We detected 241 associations, including 54 associations and 30 loci not previously linked to CAD. Next, we prioritized likely causal variants using functionally-informed fine-mapping, yielding 42 associations with fewer than five variants in the 95% credible set. Combining eight complementary predictors, we prioritized 185 candidate causal genes, including 94 genes supported by three or more predictors. Similarity-based clustering underscored a role for early developmental processes, cell cycle signaling, and vascular proliferation in the pathogenesis of CAD. Our analysis identifies and systematically characterizes risk loci for CAD to inform experimental interrogation of putative causal mechanisms for CAD.

IMPORTANCE Lipid management typically focuses on levels of low-density lipoprotein cholesterol (LDL-C) and, to a lesser extent, triglycerides (TG). However, animal models and genetic studies suggest that the atherogenic particle subpopulations (LDL and very-low-density lipoprotein [VLDL]) are both important and that the number of particles is more predictive of cardiac events than their lipid content. OBJECTIVE To determine whether common measures of cholesterol concentration, TG concentration, or their ratio are associated with cardiovascular risk beyond the number of apolipoprotein B (apoB)-containing lipoproteins. DESIGN, SETTING, AND PARTICIPANTSThis prospective cohort analysis included individuals from the population-based UK Biobank and from 2 large international clinical trials, FOURIER and IMPROVE-IT. The median (IQR) follow-up was 11.1 (10.4-11.8) years in UK Biobank and 2.5 (2.0-4.7) years in the clinical trials. Two populations were studied in this analysis: 389 529 individuals in the primary prevention group who were not taking lipid-lowering therapy and 40 430 patients with established atherosclerosis who were receiving statin treatment.EXPOSURES ApoB, non-high-density lipoprotein cholesterol (HDL-C), LDL-C, and TG. MAIN OUTCOME AND MEASURES The primary study outcome was incident myocardial infarction (MI).RESULTS Of the 389 529 individuals in the primary prevention group, 224 097 (58%) were female, and the median (IQR) age was 56.0 (49.5-62.5) years. Of the 40 430 patients with established atherosclerosis, 9647 (24%) were female, and the median (IQR) age was 63 (56.2-69.0) years. In the primary prevention cohort, apoB, non-HDL-C, and TG each individually were associated with incident MI. However, when assessed together, only apoB was associated (adjusted hazard ratio [aHR] per 1 SD, 1.27; 95% CI, 1.15-1.40; P < .001). Similarly, only apoB was associated with MI in the secondary prevention cohort. Adjusting for apoB, there was no association between the ratio of TG to LDL-C (a surrogate for the ratio of TG-rich lipoproteins to LDL) and risk of MI, implying that for a given concentration of apoB-containing lipoproteins, the relative proportions of particle subpopulations may no longer be a predictor of risk. CONCLUSIONS AND RELEVANCEIn this cohort study, risk of MI was best captured by the number of apoB-containing lipoproteins, independent from lipid content (cholesterol or TG) or type of lipoprotein (LDL or TG-rich). This suggests that apoB may be the primary driver of atherosclerosis and that lowering the concentration of all apoB-containing lipoproteins should be the focus of therapeutic strategies.