Table 1

 Baseline characteristics of 1080 patients studied

FS at initial evaluationp Value
>25%⩽25%
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.
Number of patients1054 (97.6%)26 (2.4%)NA
Men/women643/41118/90.7
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
VF19 (1.8%)0 (0.0%)NA
AF129 (12.2%)9 (34.6%)0.006
Exertional chest pain300 (28.5%)6 (23.1%)0.5
NYHA class
    I666 (63.2%)13 (50.0%)0.2
    II359 (34.1%)10 (38.5%)0.7
    III–IV29 (2.8%)3 (11.5%)0.07
Family history of HCM464 (44.0%)10 (38.5%)0.6
Family history of SCD313 (29.7%)10 (38.5%)0.3
Palpitations272 (25.8%)9 (34.6%)0.3
Syncope158 (15.0%)5 (19.2%)0.6
Abnormal BP response264 (25.0%)5 (19.2%)0.7
Non-sustained VT182 (17.3%)7 (26.9%)0.09
Severe LVH100 (9.5%)00.2
Wigle4.6 (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
    ASH674 (63.9%)12 (46.2%)0.04
    Concentric301 (28.6%)10 (38.5%)0.3
    Apical45 (4.3%)2 (7.7%)0.3
    Other/not measurable34 (3.2%)2 (7.7%)NA
LVOTG280 (26.6%)00.0005
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
    Amiodarone307 (29.1%)10 (38.5%)0.3
    β Blocker427 (40.5%)6 (23.1%)0.07
    Calcium antagonist286 (27.1%)3 (11.5%)0.8
    Disopyramide116 (11.0%)1 (3.8%)0.3
    Sotalol76 (7.2%)2 (7.7%)0.7
    Diuretic195 (18.5%)13 (50.0%)<0.0001
    ACE inhibitor82 (7.8%)13 (50.0%)<0.0001
    Pacemaker95 (9.0%)3 (11.5%)0.7
    ICD53 (5.0%)1 (3.8%)1
    Myectomy/ablation41 (3.9%)0NA