The Bilitch ICD Registry includes 1,869 patients from 13 medical centers enrolled between March 1982 and April 1992. Of these, 95 patients had their units removed and not immediately replaced (77 males/18 females mean age 54.9 +/- 13.0 years, range 10-76). The mean duration of implanted ICD was 19.5 +/- 18.2 months, mean ejection fraction 30.1 +/- 11.7%. Coronary artery disease was present in 55 patients, absent in 30, and unknown in 10. The presenting clinical event was sudden death in 35 patients, symptomatic ventricular tachycardia in 34, other causes in 6, and unknown in 20. Reasons for ICD removal were: infection in 33 patients, cardiac transplant in 32, elective in 20, following battery depletion in 7, lead system failure in 2, and inappropriate shock in 1. Of all groups who had their ICD removed, the patients who had removal for cardiac transplantation had the highest incidence of appropriate ICD discharges while the device was implanted (43.8%). Of the 63 nontransplanted patients seven were lost to follow-up while alive. Of the 56 remaining, 17 died (1 cause unknown, 6 noncardiac, 3 sudden, 1 arrhythmic, 6 nonsudden nonarrhythmic cardiac death), 7 had an ICD reimplanted, and 32 are alive and well without an ICD. Follow-up for the 32 cardiac transplant patients: 2 were lost to follow-up while alive, 2 died of nonsudden nonarrhythmic death, and 28 are alive and well. The survival of patients who had their ICD removed and not reimplanted was not different from that of patients who never had their ICD removed up to 2 years.(ABSTRACT TRUNCATED AT 250 WORDS)