Abstract 14622: Cardiac Resynchronization Therapy in Patients With RBBB in the Ontario ICD Registry; Assessment of Contemporary Practice and Outcomes.
Background: Cardiac Resynchronization Therapy (CRT) can improve outcomes in heart failure patients with prolonged QRS duration. Accumulating data suggests that patients with LBBB are most likely to respond; in contrast patients with RBBB may not benefit at all. The objectives of our study were to document the contemporary practice of CRT-D use in patients with RBBB and assess outcomes in comparison to patients receiving non-CRT ICDS
Methods: The Ontario ICD database is a prospective, multicenter, population-based clinical outcomes registry of all newly implanted defibrillator patients at 18 centers in Ontario, Canada. The Ministry of Health mandates that all ICD implants are recorded. We examined baseline characteristics and 45-day complications and long-term outcomes, in patients with RBBB, implanted between February 2007 and March 2010. Complications were categorized as major or minor.
Results: Among 7288 patients, 340 had RBBB. 101/340 (29.7%) were implanted with CRT-D and 239/340 (70.3%) were implanted with ICD. Independent predictors of receiving CRT-D were LV-EF, QRS width and NYHA class. Major complications occurred more frequently (11.9%) in RBBB patients receiving CRT-D compared to RBBB patients receiving ICD (5.4%, p=0.03). This was primarily lead dislodgement and pocket infection. Long-term risk-adjusted outcomes (mortality and heart failure hospitalizations) are being collected and will be presented at the meeting.
Conclusions: CRT-D implantation is common (29.7%) in patients with RBBB. Major complications occurred more frequently (11.9%) in RBBB patients receiving CRT-D compared to RBBB patients receiving ICD (5.4%). Risk adjusted long-term outcome data is awaited, but it is possible that the risk/benefit ratio may argue against the use of CRT in these patients.
- © 2010 by American Heart Association, Inc.