Evaluation of coronary microvascular dysfunction using magnetocardiography: A new application to an old technology.

Background: In patients with angina and non-obstructive coronary artery disease (ANOCA), diagnosis of coronary microvascular dysfunction (CMD) remains an unmet need. Magnetocardiography (MCG), is a rest-based, non-invasive scan that can detect weak electrophysiological changes that occur at the early phase of ischemia. Objective: This study assessed the ability of MCG to detect CMD in ANOCA patients as compared to reference standard, invasive coronary flow reserve (CFR). Methods: Patients with ANOCA and invasive coronary physiologic assessment using intracoronary flow measurements with Doppler and thermodilution methods were enrolled. CMD was defined dichotomously as an invasive CFR < 2.0 by Doppler or thermodilution assessment. Noninvasive 36-channel 90-s MCG scan was performed and quantitative assessment of four distinct MCG features was completed. We evaluated the diagnostic performance of 2 or more abnormal MCG features to detect CMD in the overall cohort and performed a subgroup analysis in the subset of patients with Doppler CFR assessment. Results: Among 79 ANOCA patients, 25 were CMD positive and 54 patients were CMD negative by CFR. Using invasive CFR as reference, MCG had an ROC AUC of 0.66 with a sensitivity of 68 % and specificity of 65 % for the detection of CMD. In the subgroup with Doppler CFR assessment, MCG had an ROC AUC of 0.76 with a sensitivity of 75 % and specificity of 77 %. Conclusions: In ANOCA patients, MCG demonstrates the ability to detect CMD using a 90-second non-invasive scan without the need for an intravenous stressor or ionizing radiation. Further investigations are needed to validate an MCG-based diagnostic pathway for CMD.

Comparative Cardiovascular Benefits of Bempedoic Acid and Statin Drugs.

BACKGROUND: In the CLEAR (Cholesterol Lowering via Bempedoic Acid, an ACL-Inhibiting Regimen) Outcomes trial, treatment of statin-intolerant patients with bempedoic acid produced a 21% decrease in low-density lipoprotein cholesterol (LDL-C) relative to placebo and a 13% relative reduction in the risk of major adverse cardiovascular events. OBJECTIVES: This study sought to determine whether the relationship between LDL-C lowering and cardiovascular benefit achieved with bempedoic acid resembles that observed with statins when standardized per unit change in LDL-C. METHODS: To compare the treatment effect of bempedoic acid with statins, the methodology of the Cholesterol Treatment Trialists' Collaboration (CTTC) was applied to outcomes among the 13,970 patients enrolled in the CLEAR Outcomes trial. The CTTC endpoint of "major vascular event" was a composite of coronary heart disease death, nonfatal myocardial infarction, fatal or nonfatal stroke, or coronary revascularization. HRs for CTTC-defined endpoints were normalized to 1 mmol/L differences in LDL-C levels between bempedoic acid and placebo groups. RESULTS: A first major vascular event occurred in 703 (10.1%) patients in the bempedoic acid group and 816 (11.7%) patients in the placebo group (HR: 0.85; 95% CI: 0.77-0.94). When normalized per 1 mmol/L reduction in LDL-C, the HR was 0.75 (95% CI: 0.63-0.90), comparable to the rate ratio of 0.78 reported for statins in the CTTC meta-analysis. Normalized risk reductions were similar for bempedoic acid and statins for the endpoints of major coronary events, nonfatal myocardial infarction, and coronary revascularization. CONCLUSIONS: Cardiovascular risk reduction with bempedoic acid is similar to that achieved with statins for a given absolute magnitude of LDL-C lowering. (Evaluation of Major Adverse Cardiovascular Events in Participants With, or at High Risk for, Cardiovascular Disease Who Are Statin Intolerant Treated with Bempedoic Acid [ETC-1002] or Placebo [CLEAR Outcomes]; NCT02993406).

Single Ascending and Multiple-Dose Trial of Zerlasiran, a Short Interfering RNA Targeting Lipoprotein(a): A Randomized Clinical Trial.

Importance: Lipoprotein(a) is a causal risk factor for atherosclerotic cardiovascular disease (ASCVD) and calcific aortic stenosis, with no pharmacological treatments approved by regulatory authorities. Objectives: To assess the safety and tolerability of zerlasiran, a short interfering RNA targeting hepatic synthesis of apolipoprotein(a), and effects on serum concentrations of lipoprotein(a). Design, Setting, and Participants: Single- and multiple-dose study in healthy participants and patients with stable ASCVD, respectively, with lipoprotein(a) serum concentrations greater than 150 nmol/L, conducted at 7 research sites in the US, the Netherlands, UK, and Australia between November 18, 2020, and February 8, 2023, with last follow-up on August 23, 2023. Interventions: Participants were randomized to receive (1) a single subcutaneous dose of placebo (n = 8), zerlasiran 300 mg (n = 6) or 600 mg (n = 6); or (2) 2 doses of placebo (n = 9), zerlasiran 200 mg (n = 9) at a 4-week interval or 300 mg (n = 9) or 450 mg (n = 9) at an 8-week interval. Main Outcomes Measures: The primary outcome was safety and tolerability. Secondary outcomes included serum levels of zerlasiran and effects on lipoprotein(a) serum concentrations. Results: Among 37 patients in the multiple-dose group (mean age, 56 [SD, 10.4] years; 15 [42%] women), 36 completed the trial. Among 14 participants with extended follow-up after single doses, 13 completed the trial. There were no serious adverse events. Median baseline lipoprotein(a) concentrations in the multiple-dose group were 288 (IQR, 199-352) nmol/L. Median changes in lipoprotein(a) concentration at 365 days after single doses were 14% (IQR, 13% to 15%) for the placebo group, -30% (IQR, -51% to -18%) for the 300 mg of zerlasiran group, and -29% (IQR, -39% to -7%) for the 600-mg dose group. After 2 doses, maximal median changes in lipoprotein(a) concentration were 19 (IQR, -17 to 28) nmol/L for the placebo group, -258 (IQR, -289 to -188) nmol/L for the 200 mg of zerlasiran group, -310 (IQR, -368 to -274) nmol/L for the 300-mg dose group, and -242 (IQR, -343 to -182) nmol/L for the 450-mg dose group, with maximal median percent change of 7% (IQR, -4% to 21%), -97% (IQR, -98% to -95%), -98% (IQR, -99% to -97%), and -99% (IQR, -99% to -98%), respectively, attenuating to 0.3% (IQR, -2% to 21%), -60% (IQR, -71% to -40%), -90% (IQR, -91% to -74%), and -89% (IQR, -91% to -76%) 201 days after administration. Conclusions: Zerlasiran was well tolerated and reduced lipoprotein(a) concentrations with infrequent administration. Trial Registration: ClinicalTrials.gov Identifier: NCT04606602.

A Technology-Assisted Web Application for Consumer Access to a Nonprescription Statin Medication.

BACKGROUND: Although statins reduce adverse cardiovascular outcomes, less than one-half of eligible patients receive treatment. A nonprescription statin has the potential to improve access to statins. OBJECTIVES: This study sought to assess concordance between clinician and consumer assessment of eligibility for nonprescription statin treatment using a technology assisted self-selection Web application (Web App) and evaluate effect on low-density lipoprotein cholesterol (LDL-C) levels. METHODS: This study was a prospective actual use 6-month study to evaluate use of a Web App to qualify participants without a medical background for a moderate-intensity statin based on current guidelines. Participants entered demographic information, cholesterol values, blood pressure, and concomitant medications into the Web App, resulting in 3 possible outcomes: "do not use," "ask a doctor," and "OK to use." RESULTS: The study included 1,196 participants, with a median age of 63 years (Q1-Q3: 57-68 years); 39.6% were women, 79.3% were White, 11.7% were Black, and 4.1% had limited literacy. Mean LDL-C was 139.6 ± 28.3 mg/dL and the median calculated 10-year risk of atherosclerotic cardiovascular disease was 10.1% (Q1-Q3: 7.3%-14.0%). Initial Web App self-selection resulted in an outcome concordant with clinician assessment in 90.7% (95% CI: 88.9%-92.3%) of participants, and 98.1% (95% CI: 97.1%-98.8%) had a concordant final use outcome during treatment. Mean percent change in LDL-C was -35.5% (95% CI: -36.6% to -34.3%). Serious adverse events occurred in 27 (2.3%) participants, none related to the study drug. CONCLUSIONS: In this actual use study, a technology-assisted Web App allowed >90% of consumers to correctly self-select for statin use and achieve clinically important LDL-C reductions. (Technology-Assisted Cholesterol Trial in Consumers [TACTiC]; NCT04964544).

Trends and Outcomes Associated With Bariatric Surgery and Pharmacotherapies With Weight Loss Effects Among Patients With Heart Failure and Obesity.

BACKGROUND: Utilization patterns of bariatric surgery among older patients with heart failure (HF), and the associations with cardiovascular outcomes, are not well known. METHODS: Medicare beneficiaries with HF and at least class II obesity from 2013 to 2020 were identified with Medicare Provider Analysis and Review 100% inpatient files and Medicare 5% outpatient files. Patients who underwent bariatric surgery were matched to controls in a 1:2 ratio (matched on exact age, sex, race, body mass index, HF encounter year, and HF hospitalization rate pre-surgery/matched period). In an exploratory analysis, patients prescribed pharmacotherapies with weight loss effects (semaglutide, liraglutide, naltrexone-bupropion, or orlistat) were identified and matched to controls with a similar strategy in addition to HF medical therapy data. Cox models evaluated associations between weight loss therapies (as a time-varying covariate) and mortality risk and HF hospitalization rate (calculated as the rate of HF hospitalizations following index HF encounter per 100 person-months) during follow-up. RESULTS: Of 298 101 patients with HF and body mass index ≥35 kg/m2, 2594 (0.9%) underwent bariatric surgery (45% men; mean age, 56.2 years; mean body mass index, 51.5 kg/m2). In propensity-matched analyses over a median follow-up of 4.7 years, bariatric surgery was associated with lower risk of all-cause mortality (HR, 0.55 [95% CI, 0.49-0.63]; P<0.001), greater reduction in HF hospitalization rate (rate ratio, 0.72 [95% CI, 0.67-0.77]; P<0.001), and lower atrial fibrillation risk (HR, 0.78 [95% CI, 0.65-0.93]; P=0.006). Use of pharmacotherapies with weight loss effects was low (4.8%), with 96.3% prescribed GLP-1 (glucagon-like peptide-1) agonists (semaglutide, 23.6%; liraglutide, 72.7%). In propensity-matched analysis over a median follow-up of 2.8 years, patients receiving pharmacotherapies with weight loss effects (versus matched controls) had a lower risk of all-cause mortality (HR, 0.82 [95% CI, 0.71-0.95]; P=0.007) and HF hospitalization rate (rate ratio, 0.87 [95% CI, 0.77-0.99]; P=0.04). CONCLUSIONS: Bariatric surgery and pharmacotherapies with weight loss effects are associated with a lower risk of adverse outcomes among older patients with HF and obesity; however, overall utilization remains low.

Sex-Specific Prognosis of Left Ventricular Size and Function Following Repair of Degenerative Mitral Regurgitation.

BACKGROUND: Prior studies have demonstrated worse long-term outcomes for women after surgery for severe mitral regurgitation (MR). The current Class I indications for surgery for severe degenerative MR use cutoffs of left ventricular end-systolic dimension (LVESD) and left ventricular ejection fraction (EF) that do not account for known sex-related differences. OBJECTIVES: The primary objective of this study was to assess long-term mortality following mitral valve repair in women compared with men on the basis of preoperative left ventricular systolic dimensions and EF. METHODS: Consecutive patients who underwent isolated mitral valve repair for degenerative MR at a single institution between 1994 and 2016 were screened. Adjusted HRs for all-cause mortality were compared according to baseline LVESD, LVESD indexed to body surface area (LVESDi), and EF for men and women. RESULTS: Among 4,589 patients, 1,825 were women (40%), and after a median follow-up period of 7.2 years, 344 patients (7.5%) had died. The risk for mortality for women increased from the baseline hazard at an LVESD of 3.6 cm, whereas an inflection point for increased risk with LVESD was not evident in men. Regarding LVESDi, the risk for women increased at 1.8 cm/m2 compared with 2.1 cm/m2 in men. For EF, women and men had a similar inflection point (58%); however, mortality was higher for women as EF decreased. CONCLUSIONS: After mitral valve repair, women have a higher risk for all-cause mortality at lower LVESD and LVESDi and higher EF. These results support consideration of sex-specific thresholds for LVESDi in surgical decision making for patients with severe MR.

Impact of Bempedoic Acid on Total Cardiovascular Events: A Prespecified Analysis of the CLEAR Outcomes Randomized Clinical Trial.

Importance: The ATP citrate lyase (ACL) inhibitor, bempedoic acid, reduces low-density lipoprotein cholesterol (LDL-C) level and major adverse cardiovascular events (MACE) by 13% in patients at high cardiovascular risk with intolerance of statin and high-intensity statin medications. The effects of bempedoic acid on total cardiovascular events remain unknown. Objective: To determine the impact of bempedoic acid on the total incidence of MACE. Design, Setting, and Participants: Included in this prespecified analysis of the Cholesterol Lowering via Bempedoic Acid, an ACL-Inhibiting Regimen (CLEAR) Outcomes trial were patients with, or at high risk for, cardiovascular disease, with hypercholesterolemia and inability to take guideline-recommended statins. Study data were analyzed from December 2016 to November 2022. Interventions: Patients were randomly assigned to treatment with bempedoic acid or placebo daily. Main Outcomes and Measures: The primary end point was the time to first event for a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or coronary revascularization (MACE-4). The key secondary end point was time to first event for cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke (MACE-3). This prespecified analysis compared the total number of cardiovascular events in the treatment groups. Results: A total of 13 970 patients (mean [SD] age, 65 [9] years; 7230 male [51.8%]) were included in the study. A total of 9764 participants (69.9%) had prior atherosclerotic cardiovascular disease and a baseline LDL-C level of 139 mg/dL; treatment with bempedoic acid resulted in a 21% reduction in LDL-C level and a 22% reduction in high-sensitivity C-reactive protein (hsCRP) level at 6 months. Median (IQR) follow-up was 3.4 (3.1-3.9) years. A total of 1746 positively adjudicated first MACE-4 events and 915 additional MACE events in 612 patients were recorded, with coronary revascularization representing 32.8% (573 of 1746) of first events and 69.4% (635 of 915) of additional events. For the total incidence of cardiovascular events, treatment with bempedoic acid was associated with a reduction in risk of MACE-4 (hazard ratio [HR], 0.80; 95% CI, 0.72-0.89; P <.001), MACE-3 (HR, 0.83; 95% CI, 0.73-0.93; P = .002), myocardial infarction (HR, 0.69; 95% CI, 0.58-0.83; P < .001), and coronary revascularization (HR, 0.78; 95% CI, 0.68-0.89; P <.001), although no statistically significant difference was observed for stroke (HR, 0.80; 95% CI, 0.63-1.03). A lower HR for protection with bempedoic acid was observed with increasing number of MACE events experienced by patients. Conclusion and Relevance: Lowering LDL-C level with bempedoic acid reduced the total number of cardiovascular events in patients with high cardiovascular risk, statin therapy intolerance, and elevated LDL-C levels.

Nonstatin therapy to reduce low-density lipoprotein cholesterol and improve cardiovascular outcomes.

Atherosclerotic cardiovascular disease (ASCVD) is a leading cause of morbidity and mortality, with low-density lipoprotein (LDL) cholesterol being a causative risk factor. Though statins have a decades-long track record of efficacy and safety, nonstatin agents may be used to reduce LDL cholesterol as an adjunct or alternative to statin therapy. Several new nonstatin medications have been approved in recent years, with robust data from clinical trials supporting their use in atherosclerotic disease. This review addresses the indications, evidence, and important prescribing considerations for using nonstatin lipid-lowering therapy and proposes a practical approach for determining when to initiate nonstatin therapy.

Coronary spasm and vasomotor dysfunction as a cause of MINOCA.

Increasing evidence has shown that coronary spasm and vasomotor dysfunction may be the underlying cause in more than half of myocardial infarctions with non-obstructive coronary arteries (MINOCA) as well as an important cause of chronic chest pain in the outpatient setting. We review the contemporary understanding of coronary spasm and related vasomotor dysfunction of the coronary arteries, the pathophysiology and prognosis, and current and emerging approaches to diagnosis and evidence-based treatment.