Table 1

Baseline Clinical and Procedural Characteristics of the Study Population According to Year of Implantation

Overall
(n = 176)
Group I
(n = 82)
Group II
(n = 94)
p Value
Age, yrs43.3 ± 16.842.5 ± 15.344.0 ± 18.20.46
Male118 (67.0)62 (75.6)56 (59.6)0.02
Spontaneous type 1 ECG pattern37 (21.0)28 (34.1)9 (9.6)<0.01
Aborted SCD25 (14.2)15 (18.3)10 (10.6)0.15
Syncope105 (59.7)39 (47.6)66 (70.2)<0.01
Asymptomatic46 (26.1)28 (34.1)18 (19.1)0.01
Family history of SCD90 (51.1)47 (57.3)43 (45.7)0.13
Previous atrial arrhythmias24 (13.6)14 (17.1)10 (10.6)0.22
Previous SND9 (5.1)6 (7.3)3 (3.2)0.31
Inducible on EPS72 (43.6)58 (75.3)14 (15.9)<0.01
SCN5A mutation23 (21.9)13 (21.7)10 (22.2)0.95
Abdominal implantation19 (10.8)6 (7.3)13 (13.8)0.19
Epicardial lead placement8 (4.5)3 (3.7)5 (5.3)0.73

Values are mean ± SD or n (%). Group I included patients who underwent ICD placement before 2005, and group II included patients who underwent ICD placement during or after 2005.

ECG = electrocardiographic; EPS = electrophysiologic study; ICD = implantable cardioverter-defibrillator; SCD = sudden cardiac death; SND = sinus node dysfunction.

  • Percents refer to patients who underwent EPS and genetic testing.