Hegde, Sheila M

Background This study aims to characterize right ventricular dysfunction (RVD) in heart failure (HF) with preserved ejection fraction and understand the cumulative prognostic value of abnormal RV echocardiographic parameters in HF with preserved ejection fraction. Methods and Results Data from 809 patients in the PARAGON‐HF (Prospective Comparison of Angiotensin Receptor–Neprilysin Inhibitor With Angiotensin‐Receptor Blocker Global Outcomes in HF With Preserved Ejection Fraction) echocardiographic substudy (55% women, mean age 74±8 years) were analyzed. Correlates of RVD (defined as tricuspid annular plane systolic excursion <1.7 cm, fractional area change <35% or absolute RV free wall longitudinal strain <20%) were identified using multivariable logistic regression models. We further assessed the prognostic value of the number of abnormal RV parameters (0, 1, ≥2) on total HF hospitalizations (HFH) and cardiovascular death, total HFH, first HFH or cardiovascular death, all‐cause death, and cardiovascular death. RVD was identified in 461 (57%) patients. Correlates of RVD included older age, higher heart rate, atrial fibrillation/flutter, greater left ventricle wall thickness, higher N‐terminal pro‐B‐type natriuretic peptide levels, lower systolic blood pressure, and lower left ventricle absolute global longitudinal strain. These results were consistent across sexes, except atrial fibrillation/flutter and LV wall thickness, which were associated with a higher risk of RVD in men but not in women. Participants with ≥2 abnormal RV parameters had a significantly higher adjusted risk of total HFH and cardiovascular death (rate ratio, 2.13 [95% CI, 1.13–4.01]), first HFH or cardiovascular death, all‐cause death, and cardiovascular death. Conversely, an isolated abnormal RV parameter was not associated with a worse outcome. Conclusions RV measures may underestimate the burden of RVD in HF with preserved ejection fraction when considered in isolation. Clinicians should consider multiple dimensions to comprehensively assess RV function in patients with HF with preserved ejection fraction.

Background The phase 2 PIONEER‐HCM (Phase 2 Open‐label Pilot Study Evaluating Mavacamten in Subjects With Symptomatic Hypertrophic Cardiomyopathy and Left Ventricular Outflow Tract Obstruction) study showed that mavacamten improved left ventricular outflow tract gradients, exercise capacity, and symptoms in patients with obstructive hypertrophic cardiomyopathy (HCM), but the results of longer‐term treatment are less well described. We report interim results from the PIONEER‐OLE (PIONEER Open‐Label Extension) study, the longest‐term study of mavacamten in patients with symptomatic obstructive HCM. Methods and Results Patients who previously completed PIONEER‐HCM (n=20) were eligible to enroll in PIONEER‐OLE. Patients received oral mavacamten, 5 mg once daily (starting dose), with individualized dose titration at week 6. Evaluations included serial monitoring of safety, echocardiography, Kansas City Cardiomyopathy Questionnaire–Overall Summary Score, and serum NT‐proBNP (N‐terminal pro‐B‐type natriuretic peptide) levels. Thirteen patients enrolled and received mavacamten (median study duration at data cutoff, 201 weeks). Most patients (92.3%) received β‐blockers concomitantly. Treatment‐emergent adverse events were predominantly mild/moderate. One patient had an isolated reduction in left ventricular ejection fraction to 47%, which recovered and remained normal with continued treatment at a reduced dose. At week 180, mavacamten was associated with New York Heart Association class improvements from baseline (class II to I, n=9; class III to II, n=1; and unchanged, n=2), sustained reductions in left ventricular outflow tract gradients (mean [SD] change from baseline: resting, −50 [55] mm Hg; Valsalva, −70 [41] mm Hg), and serum NT‐proBNP levels (median [interquartile range] change from baseline: −498 [−2184 to −76] ng/L), and improved Kansas City Cardiomyopathy Questionnaire–Overall Summary Score (mean [SD] change from baseline: +17 [16]). Conclusions This long‐term analysis supports the continued safety and effectiveness of mavacamten for >3 years in obstructive HCM. Registration URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03496168.