Table 1. Baseline Characteristicsa.
| Characteristic | Aficamten (n = 142) | Placebo (n = 140) |
|---|---|---|
| Age, y | 59.2 (12.6) | 59.0 (13.3) |
| Sex, No. (%) | ||
| Female | 56 (39.4) | 59 (42.1) |
| Male | 86 (60.6) | 81 (57.9) |
| Race, No. (%) | ||
| Asian | 29 (20.4) | 25 (17.9) |
| Black or African American | 3 (2.1) | 0 |
| White | 108 (76.1) | 115 (82.1) |
| Otherb | 2 (1.4) | 0 |
| Geographic region, No. (%) | ||
| North America | 49 (34.5) | 45 (32.1) |
| China | 24 (16.9) | 22 (15.7) |
| Europe and Israel | 69 (48.6) | 73 (52.1) |
| Medical history, No. (%) | ||
| Hypertension | 75 (52.8) | 70 (50.0) |
| Family history or known gene variant | 47 (33.1) | 44 (31.4) |
| Family history of HCM | 41 (28.9) | 34 (24.3) |
| Pathogenic sarcomere variant | 24 (16.9) | 25 (17.9) |
| Paroxysmal atrial fibrillation | 21 (14.8) | 20 (14.3) |
| Coronary artery disease | 19 (13.4) | 16 (11.4) |
| Diabetes | 14 (9.9) | 9 (6.4) |
| Permanent atrial fibrillation | 2 (1.4) | 1 (0.7) |
| Background HCM therapy, No. (%) | ||
| β-Blocker | 86 (60.6) | 87 (62.1) |
| Calcium channel blocker | 45 (31.7) | 36 (25.7) |
| Disopyramide | 16 (11.3) | 20 (14.3) |
| None | 19 (13.4) | 22 (15.7) |
| Symptoms | ||
| KCCQ-CSS | 76 (18) | 74 (18) |
| NYHA functional class, No. (%) | ||
| II | 108 (76.1) | 106 (75.7) |
| III | 34 (23.9) | 33 (23.6) |
| IV | 0 | 1 (0.7) |
| Cardiac biomarkers | ||
| Median NT-proBNP (IQR), pg/mL | 818 (377-1630) | 692 (335-1795) |
| Median hs-cTnl (IQR), ng/L | 12.9 (7.6-33.6) | 11.5 (7.7-25.0) |
| Echocardiographic parameters | ||
| Valsalva LVOT-G, mm Hg | 83 (32) | 83 (33) |
| Resting LVOT-G, mm Hg | 55 (27) | 55 (32) |
| LVEF, % | 75 (5.5) | 75 (6.3) |
| LAVI, mL/m2 | 40.1 (12.7) | 40.9 (15.1) |
| Maximal wall thickness, cm | 2.1 (0.3) | 2.1 (0.3) |
| Cardiopulmonary exercise test parameters | ||
| Integrated 2-component exercise performance metric | −0.01 (0.82) | 0.02 (0.75) |
| pVO2, mL/kg/min | 18.4 (4.5) | 18.6 (4.6) |
| Workload, W | 120 (40) | 126 (43) |
| Metabolic equivalents, METS | 5.3 (1.3) | 5.3 (1.3) |
| Ventilatory efficiency throughout exercise (VE/VCO2 slope) | 33.2 (6.4) | 32.9 (6.0) |
Abbreviations: HCM, hypertrophic cardiomyopathy; hs-cTnI, high-sensitivity cardiac troponin I; KCCQ-CSS, Kansas City Cardiomyopathy Questionnaire Clinical Summary Score; LAVI, left atrial volume index; LVEF, left ventricular ejection fraction; LVOT-G, left ventricular outflow tract gradient; NT-proBNP, N-terminal pro–brain natriuretic peptide; NYHA, New York Heart Association; pVO2, peak oxygen uptake; VCO2, carbon dioxide output; VE, minute ventilation.
SI conversion factors: To convert hs-cTnI to micrograms per liter, divide by 1000 and multiply by 1; NT-proBNP to nanograms per liter, multiply by 1.
Percentages may not total 100 because of rounding. Value in parenthesis represents the SD unless otherwise specified.
Race was denoted by the patient as part of baseline characteristics. Other ethnic groups included American Indian or Alaska Native, Native Hawaiian or Other Pacific Islander; multiracial; and not reported.