Table 1 Baseline characteristics

	n = 181	(%)
Age, mean (SD)	44 (17) years
Gender (male)	112	62
Ejection fraction (%), mean (SD)	68 (10)
Left ventricular outflow tract gradient at implant (n = 170), mean (SD)	25.56 (33.47) mm Hg
Septal thickness at implant (n = 166), mean (SD)	20.49 (6.66) mm
ICD indication
Primary prevention	155	86
Family history of sudden cardiac arrest	87	56*
Septal hypertrophy	25	16*
Syncope	62	40*
Non-sustained ventricular tachycardia	64	42*
Other	5	3*
<2 risk factor	82	54*
⩾2 risk factors	71	46*
Secondary prevention	26	14
Defibrillation threshold testing at implant (n = 174), mean (SD)	14 (5) J
Dual chamber ICD	108	60
Single chamber ICD	65	36
Epicardial ICD	8	4
Sinus node dysfunction	12	7
Heart block	17	9
Myectomy	72	40
Septal ablation	10	6
Atrial fibrillation	79	44
Creatinine, mean (SD)	1.09 (0.26) mg/dl
Medications
Diuretics	32	18
Beta blockers	119	66
Calcium-channel blockers	41	23
ACE inhibitors	15	8
Angiotensin-receptor blockers	4	2
Nitrates (long-acting)	1	1
Digoxin	7	4
Class IA antiarrhythmic drugs	11	6
Class IB antiarrhythmic drugs	0	0
Class IC antiarrhythmic drugs	2	1
Class III antiarrhythmic drugs	20	12