Table 1.

Baseline Characteristics

	Group A (n=16 230)	Group B (n=7973)	P Value
Age at GE, y	71.3±11.6	68.8±12.5	<0.001
Male sex, %	70.9	76.9	<0.001
Time of first battery implant, y	5.4±1.3	5.3±1.2	<0.001
Device type, %			<0.001
Single‐chamber ICD	21.4	25.5
Dual‐chamber ICD	34.0	37.4
Biventricular ICD	44.6	37.1
Tachytherapy device programming, %			<0.001
1 zone	27.7	20.6
2 zones	51.5	53.4
3 zones	20.8	26.0
VT dectection rate, bpm	174±14	172±16	<0.001
VF detection rate, bpm	202±17	203±18	<0.001
Afib burden >5%*, %	24.5	31.9	<0.001
RV pacing >5%, %	42.9	47.0	<0.001
LV pacing >95%*, %	75.9	61.8	<0.001
DFT performed at GE, %	69.7	68.3	0.025

Afib indicates atrial fibrillation; bpm, beats per minute; DFT, defibrillation threshold testing; GE, generator exchange; ICD, implantable cardioverter‐defibrillator; LV, left ventricle; RV, right ventricle; VF, ventricular fibrillation; VT, ventricular tachycardia.

^*Among patients with atrial leads.

^*Among patients with cardiac resynchronization devices.