Table 4.
Phenotypes in Carriers of Pathogenic/Likely Pathogenic Variants Associated with Hypertrophic Cardiomyopathy
| Carriers (N=30) | Noncarriers (N=150) | P value | |
|---|---|---|---|
| Demographics | |||
| Age, years | 71.2 ± 10.0 | 71.2 ± 9.9 | NA |
| Female | 9 (30%) | 45 (30%) | |
| Genetic ancestry | |||
| European | 29 (97%) | 145 (97%) | |
| African | 1 (3%) | 1 (3%) | |
| Imaging | |||
| Individuals with TTE or CMR | 29 (97%) | 123 (82%) | 0.05 |
| Unexplained LVH ≥1.5 cm | 6 (21%) | 0 | 3×10 −5 |
| Unexplained LVH ≥1.3 cm | 8 (28%) | 0 | 7×10 −7 |
| Unexplained LVH ≥1.3 cm or secondary LVH ≥1.8 cm | 19 (66%) | 14 (11%) | 8×10 −9 |
| Peak LVOT gradient ≥30 mmHg | 7 (24%) | 1 (1%) | 0.0001 |
| Systolic anterior motion of mitral valve leaflets | 4 (14%) | 0 | 0.001 |
| Mitral regurgitation | 9 (31%) | 20 (16%) | 0.1 |
| Diastolic dysfunction | 21 (72%) | 91 (76%) | 0.8 |
| Individuals with CMR | 3 (10%) | 22 (15%) | 0.8 |
| Late gadolinium enhancement | 3 (100%) | 15 (68%) | 0.5 |
| Maximal left ventricular wall thickness, cm | 1.8 ± 0.6 | 1.4 ± 0.3 | 1×10 −6 |
| Left atrial diameter, cm | 5.0 ± 0.8 | 4.5 ± 0.8 | 0.005 |
| Left ventricular ejection fraction, % | 43 ± 14 | 49 ± 13 | 0.03 |
| Electrocardiogram | |||
| Individuals with electrocardiogram | 26 (87%) | 142 (95%) | 0.1 |
| Left ventricular hypertrophy | 6 (23%) | 7 (5%) | 0.006 |
| T wave inversions | 15 (58%) | 26 (18%) | 7×10 −5 |
| Left bundle branch block | 4 (15%) | 8 (6%) | 0.09 |
| Right bundle branch block | 1 (4%) | 24 (17%) | 0.1 |
| Intraventricular conduction delay | 4 (15%) | 5 (4%) | 0.03 |
| QRS interval, ms | 106 ± 31 | 104 ± 25 | 0.8 |
| Arrhythmias | |||
| Atrial fibrillation/flutter | 17 (57%) | 57 (38%) | 0.07 |
| Nonsustained ventricular tachycardia | 11 (37%) | 18 (12%) | 0.002 |
| Sustained ventricular tachycardia or VF | 6 (20%) | 17 (11%) | 0.2 |
| Sudden cardiac arrest | 4 (13%) | 6 (4%) | 0.06 |
| Other findings | |||
| Family history of sudden cardiac arrest | 4 (13%) | 1 (1%) | 0.003 |
| Syncope | 13 (43%) | 13 (9%) | 2×10 −5 |
| Heart failure | 22 (73%) | 68 (45%) | 0.009 |
| Implantable cardioverter-defibrillator | 9 (30%) | 17 (11%) | 0.02 |
| Septal reduction therapy | 6 (20%) | 0 | 1×10 −5 |
| Alcohol septal ablation | 2 (33%) | NA | NA |
| Surgical myectomy | 4 (67%) | ||
| Heart transplantation | 5 (17%) | 4 (3%) | 0.007 |
| Individuals with histopathology | 6 (20%) | 2 (1%) | 0.0003 |
| Findings consistent with HCM | 5 (83%) | 0 | 0.1 |
| Obstructive coronary artery disease | 14 (47%) | 100 (67%) | 0.06 |
Continuous measures are described as mean ± standard deviation and are compared using the two-sided Student’s t-test. Categorical variables are described as N (%) and are compared using Fisher’s exact test. P values in bold indicate p <0.05. CMR, cardiac magnetic resonance imaging; HCM, hypertrophic cardiomyopathy; LVH, left ventricular hypertrophy; LVOT, left ventricular outflow tract; NA, not applicable; TTE, echocardiogram; VF, ventricular fibrillation.