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The First Year Experience with the Dual Chamber ICD

In July 1997, a dual chamber pacemaker combined with a tiered therapy implantable cardioverter defibrillator (ICD) first became available in the United States. We report the first‐year experience of one center in the United States with this dual chamber ICD. Of a total of 174 ICDs, 95 (55%) were dual chamber devices and 79 (45%) were single chamber. New dual chamber ICD insertions averaged 57.4 ± 8.9 minutes, though there was a learning curve as the last 30 implants averaged 45.1 ± 6.1 minutes with a negative slope to the regression line of procedure duration (−0.52, P < 0.05). New single chamber ICD implants were 18.5 minutes quicker (38.9 ± 7.2 minutes). The most challenging implants were dual chamber upgrades (mean procedure duration 64.9 ± 15.8 minutes), especially if there was a previously implanted pacemaker and ICD at separate sites. Indications for a new dual chamber device were grouped into classic pacemaker indications (52.5%), which comprised the Class I ACC/AHA guidelines, ICD‐specific indications (24.6%), and other (23.0%). In the 34 patients undergoing dual chamber upgrade, the classic and ICD‐specific groups were equal (47.0% each). Complications were rare (2.8%), though 3 (8.8%) of 34 undergoing a dual chamber upgrade developed late infections requiring explanation. In its first year, the dual chamber ICD has become a common device at our institution comprising 55% of new implants. As experience grows, we anticipate similar usage at most institutions.