Table 1.
Baseline characteristics of 1080 patients studied
| FS at initial evaluation | p Value | ||
| >25% | ⩽25% | ||
| Number of patients | 1054 (97.6%) | 26 (2.4%) | NA |
| Men/women | 643/411 | 18/9 | 0.7 |
| Age (years) | 42 (15) (16–88) | 49 (14) (18–73) | 0.03 |
| Age at diagnosis (years) | 38 (16) (3–88) | 38 (19) (5–73) | 0.9 |
| Follow up (months) | 59 (49) (0–307) | 42 (40) (0–119) | 0.04 |
| VF | 19 (1.8%) | 0 (0.0%) | NA |
| AF | 129 (12.2%) | 9 (34.6%) | 0.006 |
| Exertional chest pain | 300 (28.5%) | 6 (23.1%) | 0.5 |
| NYHA class | |||
| I | 666 (63.2%) | 13 (50.0%) | 0.2 |
| II | 359 (34.1%) | 10 (38.5%) | 0.7 |
| III–IV | 29 (2.8%) | 3 (11.5%) | 0.07 |
| Family history of HCM | 464 (44.0%) | 10 (38.5%) | 0.6 |
| Family history of SCD | 313 (29.7%) | 10 (38.5%) | 0.3 |
| Palpitations | 272 (25.8%) | 9 (34.6%) | 0.3 |
| Syncope | 158 (15.0%) | 5 (19.2%) | 0.6 |
| Abnormal BP response | 264 (25.0%) | 5 (19.2%) | 0.7 |
| Non-sustained VT | 182 (17.3%) | 7 (26.9%) | 0.09 |
| Severe LVH | 100 (9.5%) | 0 | 0.2 |
| Wigle | 4.6 (2.7) (0–10) | 2.3 (2.5) (0–8) | <0.0001 |
| MLVWT (mm) | 20.3 (6.1) (8–49) | 18.2 (4.2) (13–25) | 0.07 |
| Pattern | |||
| ASH | 674 (63.9%) | 12 (46.2%) | 0.04 |
| Concentric | 301 (28.6%) | 10 (38.5%) | 0.3 |
| Apical | 45 (4.3%) | 2 (7.7%) | 0.3 |
| Other/not measurable | 34 (3.2%) | 2 (7.7%) | NA |
| LVOTG | 280 (26.6%) | 0 | 0.0005 |
| LVEDD (mm) | 43.8 (5.8) (24–65) | 51.5 (10.6) (32–82) | 0.001 |
| LVESD (mm) | 24.9 (5.6) (10–45) | 41.0 (9.0) (24–61) | <0.0001 |
| FS (%) | 43.1 (8.2) (26–72) | 20.2 (5.2) (9–25) | <0.0001 |
| LA diameter (mm) | 43.0 (7.9) (20–75) | 51.3 (9.2) (34–73) | <0.0001 |
| Medication/procedures during follow up | |||
| Amiodarone | 307 (29.1%) | 10 (38.5%) | 0.3 |
| β Blocker | 427 (40.5%) | 6 (23.1%) | 0.07 |
| Calcium antagonist | 286 (27.1%) | 3 (11.5%) | 0.8 |
| Disopyramide | 116 (11.0%) | 1 (3.8%) | 0.3 |
| Sotalol | 76 (7.2%) | 2 (7.7%) | 0.7 |
| Diuretic | 195 (18.5%) | 13 (50.0%) | <0.0001 |
| ACE inhibitor | 82 (7.8%) | 13 (50.0%) | <0.0001 |
| Pacemaker | 95 (9.0%) | 3 (11.5%) | 0.7 |
| ICD | 53 (5.0%) | 1 (3.8%) | 1 |
| Myectomy/ablation | 41 (3.9%) | 0 | NA |
Data are mean (SD (range) or number (%).
ACE, angiotensin converting enzyme; AF, atrial fibrillation; ASH, symmetrical septal hypertrophy; BP, blood pressure during exercise; FS, fractional shortening; HCM, hypertrophic cardiomyopathy; ICD, implantable cardioverter-defibrillator; LA, left atrial; LVEDD, left ventricular end diastolic diameter (mm); LVESD, left ventricular end systolic diameter; LVH, left ventricular hypertrophy; LVOTG, left ventricular outflow tract gradient ⩾30 mm Hg; MLVWT, maximum left ventricular wall thickness; NA, not applicable; NYHA, New York Heart Association functional class; SCD, sudden cardiac death; VF, ventricular fibrillation before evaluation; VT, ventricular tachycardia.