Implantable cardioverter-defibrillators (ICDs) have conventionally been implanted in an operating room under general anesthesia. This study was performed to evaluate ICD implantation without general anesthesia by 2 electrophysiologists in an electrophysiology laboratory. Between February and September 1994, 27 consecutive patients (22 men and 5 women, mean age 59 +/- 15 years) who underwent ICD implantation by 2 electrophysiologists were included in this study. Fourteen patients received biphasic waveform ICDs, and the remaining 13 had monophasic waveform devices. All patients received local anesthesia and intravenous sedation for implantation. Implantation was successful in 23 of 27 patients at first attempt (11 of 11 with biphasic and 12 of 16 with monophasic waveform ICDs, respectively). Of 4 patients in whom implantation was initially unsuccessful, 3 subsequently received biphasic devices and 1 had improved defibrillation threshold ( < or = 26 J) on repeat testing after amiodarone withdrawal. Mean implantation time was 128 +/- 51 minutes, with 132 +/- 35 minutes under sedation. Patients who received biphasic versus monophasic waveform ICDs had no significant differences in mean sedation or implantation time. Minor complications occurred in 2 patients (7%): 1 minor abdominal pocket hematoma and 1 incision-site cellulitis. Mean time from implantation to discharge was 2.5 +/- 2.1 days. During late follow-up (n = 23; mean 12.4 +/- 5.8 weeks), all devices were functioning appropriately. In conclusion, this report demonstrates that ICD implantation can be successfully and safely performed by a team of 2 electrophysiologists using local anesthesia and intravenous sedation.(ABSTRACT TRUNCATED AT 250 WORDS)