Developments in Exercise Capacity Assessment in Heart Failure Clinical Trials and the Rationale for the Design of METEORIC-HF

Proteomic analysis of cardiorespiratory fitness for prediction of mortality and multisystem disease risks

Despite the wide effects of cardiorespiratory fitness (CRF) on metabolic, cardiovascular, pulmonary and neurological health, challenges in the feasibility and reproducibility of CRF measurements have impeded its use for clinical decision-making. Here we link proteomic profiles to CRF in 14,145 individuals across four international cohorts with diverse CRF ascertainment methods to establish, validate and characterize a proteomic CRF score. In a cohort of around 22,000 individuals in the UK Biobank, a proteomic CRF score was associated with a reduced risk of all-cause mortality (unadjusted hazard ratio 0.50 (95% confidence interval 0.48-0.52) per 1 s.d. increase). The proteomic CRF score was also associated with multisystem disease risk and provided risk reclassification and discrimination beyond clinical risk factors, as well as modulating high polygenic risk of certain diseases. Finally, we observed dynamicity of the proteomic CRF score in individuals who undertook a 20-week exercise training program and an association of the score with the degree of the effect of training on CRF, suggesting potential use of the score for personalization of exercise recommendations. These results indicate that population-based proteomics provides biologically relevant molecular readouts of CRF that are additive to genetic risk, potentially modifiable and clinically translatable.

Iron Deficiency in Heart Failure: A Scientific Statement from the Heart Failure Society of America

Iron deficiency is present in approximately 50% of patients with symptomatic heart failure and is independently associated with worse functional capacity, lower quality of, life and increased mortality. The purpose of this document is to summarize current knowledge of how iron deficiency is defined in heart failure and its epidemiology and pathophysiology, as well as pharmacological considerations for repletion strategies. This document also summarizes the rapidly expanding array of clinical trial evidence informing when, how, and in whom to consider iron repletion.

The medical treatment of cardiogenic shock

Cardiogenic shock (CS) is a leading cause of mortality worldwide. CS presentation and management in the current era have been widely depicted in epidemiological studies. Its treatment is codified and relies on medical care and extracorporeal life support (ECLS) in the bridge to recovery, chronic mechanical device therapy, or transplantation. Recent improvements have changed the landscape of CS. The present analysis aims to review current medical treatments of CS in light of recent literature, including addressing excitation-contraction coupling and specific physiology on applied hemodynamics. Inotropism, vasopressor use, and immunomodulation are discussed as pre-clinical and clinical studies have focused on new therapeutic options to improve patient outcomes. Certain underlying conditions of CS, such as hypertrophic or Takotsubo cardiomyopathy, warrant specifically tailored management that will be overviewed in this review.

KCCQ total symptom score, clinical outcome measures, and adverse events associated with omecamtiv mecarbil for heart failure with reduced ejection fraction: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Omecamtiv mecarbil (OM) is a direct myosin activator that augments left ventricular systolic function. This review compares OM to placebo by evaluating its effect on clinical outcomes and adverse events in patients with heart failure with reduced left ventricular ejection fraction.

METHODS AND RESULTS

A literature search of multiple databases for randomized controlled trials (RCTs) investigating OM versus placebo was undertaken. Six RCTs comprising 9596 patients were included. Use of OM was associated with a reduced risk of stroke (RR: 0.69; 95% CI 0.52-0.92). There was no significant mean difference (MD) change in the KCCQ total symptom score (MD: 1.82, 95% CI - 1.33 to 4.97), all-cause death (RR: 1.00; 95% CI 0.93-1.07), hospital readmissions (RR: 0.96; 95% CI 0.90-1.03), myocardial infarction (RR: 1.05; 95% CI 0.83-1.33), cardiovascular death (RR: 1.01; 95% CI 0.92-1.10), heart failure (HF) events (RR: 0.95; 95% CI 0.89-1.02), or a composite of cardiovascular death or HF events (RR: 0.97; 95% CI 0.93-1.02). In addition, OM was associated with an increased risk of dizziness (RR: 1.25; 95% CI 1.04-1.50) and hypotension (RR: 1.17; 95% CI 1.01-1.36). Other adverse events including ventricular tachyarrhythmias, (RR: 0.95; 95% CI 0.82-1.11), supraventricular tachyarrhythmias and atrial fibrillation/flutter (RR: 0.73; 95% CI 0.46-1.18), dyspnea (RR: 1.00; 95% CI 0.86-1.18), and acute renal injury (RR: 0.88; 95% CI 0.60-1.27) were not significant.

CONCLUSION

OM is generally well tolerated. We identified a reduced risk of stroke with use of OM. However, there was no improvement in other clinical outcomes or quality of life. Study protocol was registered in PROSPERO international prospective register of systematic reviews (CRD42022348423).

Effect of Omecamtiv Mecarbil on Exercise Capacity in Chronic Heart Failure With Reduced Ejection Fraction: The METEORIC-HF Randomized Clinical Trial

IMPORTANCE

Exercise limitation is a cardinal manifestation of heart failure with reduced ejection fraction (HFrEF) but is not consistently improved by any of the current guideline-directed medical therapies.

OBJECTIVE

To determine whether omecamtiv mecarbil, a novel direct myosin activator that improves cardiac performance and reduces the risk for cardiovascular death or first HF event in HFrEF, can improve peak exercise capacity in patients with chronic HFrEF.

DESIGN, SETTING, AND PARTICIPANTS

Phase 3, double-blind, placebo-controlled randomized trial of patients with HFrEF (left ventricular ejection fraction ≤35%), New York Heart Association class II-III symptoms, N-terminal pro-B-type natriuretic peptide level of 200 pg/mL or greater, and baseline peak oxygen uptake (V̇o2) of 75% or less of predicted. Patients were randomized in a 2:1 ratio (omecamtiv mecarbil to placebo) between March 2019 and May 2021 at 63 sites in North America and Europe, with the last patient visit occurring on November 29, 2021.

INTERVENTIONS

Omecamtiv mecarbil (n = 185) or matching placebo (n = 91), given orally twice daily at a dose of 25 mg, 37.5 mg, or 50 mg based on target plasma levels, for 20 weeks.

MAIN OUTCOMES AND MEASURES

The primary end point was a change in exercise capacity (peak V̇o2) from baseline to week 20. Secondary end points included total workload, ventilatory efficiency, and daily physical activity as determined by accelerometry.

RESULTS

Among 276 patients who were randomized (median age, 64 years; IQR, 55-70 years; 42 women [15%]), 249 (90%) completed the trial. The median left ventricular ejection fraction was 28% (IQR, 21-33) and the median baseline peak V̇o2 was 14.2 mL/kg/min (IQR, 11.6-17.4) in the omecamtiv mecarbil group and 15.0 mL/kg/min (IQR, 12.0-17.2) in the placebo group. Mean change in peak V̇o2 did not differ significantly between the omecamtiv mecarbil and placebo groups (mean, -0.24 mL/kg/min vs 0.21 mL/kg/min; least square mean difference, -0.45 mL/kg/min [95% CI, -1.02 to 0.13]; P = .13). Adverse events included dizziness (omecamtiv mecarbil: 4.9%, placebo: 5.5%), fatigue (omecamtiv mecarbil: 4.9%, placebo: 4.4%), heart failure events (omecamtiv mecarbil: 4.9%, placebo: 4.4%), death (omecamtiv mecarbil: 1.6%, placebo: 1.1%), stroke (omecamtiv mecarbil: 0.5%, placebo: 1.1%), and myocardial infarction (omecamtiv mecarbil: 0%, placebo: 1.1%).

CONCLUSIONS AND RELEVANCE

In patients with chronic HFrEF, omecamtiv mecarbil did not significantly improve exercise capacity over 20 weeks compared with placebo. These findings do not support the use of omecamtiv mecarbil for treatment of HFrEF for improvement of exercise capacity.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03759392.