Background: Despite improvements in cardiac resynchronization therapy (CRT) implantation techniques, a significant minority of CRT attempts are unsuccessful. Inability to cannulate the coronary sinus (CS) because of difficult anatomy is a major reason for unsuccessful CRT implantation. Direct visualization of intracardiac structures during the implant may facilitate access into the CS. The present study describes CRT implantation with the aid of an endocardial visualization catheter (EVC).
Methods: Fifty-eight consecutive patients (mean age 72 +/- 12 years; ejection fraction 26.2% +/- 7.0%; New York Heart Association [NYHA] class 2.9) underwent CRT implantation using a steerable fiberoptic EVC (Acumen Medical, Inc., Sunnyvale, CA).
Results: The EVC was able to visualize the CS ostium in all cases. The CS was successfully cannulated in 57 (98.3%) of 58 patients. The time from vascular access to CS visualization was 6 +/- 5 minutes, and the total time to CS access was 8 +/- 6 minutes. Successful left ventricle (LV) lead implantation was accomplished in 55 (94.8%) of 58 patients. Three patients who had a previous history of failed LV lead implantation were successfully implanted using the EVC.
Conclusion: Fiberoptic imaging of intracardiac structures during CRT implantation may be performed rapidly in a wide range of patients with an EVC. The ability to visualize right atrial anatomy may aid CS access and LV lead implantation.