Endocardial Left Ventricular Pacing across the Inter-Ventricular Septum for Cardiac Resynchronization Therapy - Clinical Results of a pilot study.
Gamble JHP., Herring N., Ginks MR., Rajappan K., Bashir Y., Betts TR.
BACKGROUND: Cardiac Resynchronization Therapy (CRT) is an effective treatment for selected patients with heart failure, but can be limited by the inability to place the left ventricular (LV) lead via the coronary sinus. OBJECTIVE: We have developed an alternative approach, placing the LV lead endocardially via an interventricular septal puncture; this study was designed to assess the feasibility and safety of this technique. METHODS: All patients were anticoagulated with warfarin (INR 2.5-3.5). A superior approach ventricular transseptal puncture using radiofrequency energy was performed. An active-fixation pacing lead was delivered to the mapped site of latest electrical activation on the endocardial LV. RESULTS: 20 patients were recruited, 15 with failed transvenous LV lead placement and 5 non-responders to CRT. Age was 67±12, 80% male, QRS duration 157±14ms, ischemic 45%, NYHA class 2.9±0.4, LV ejection fraction (LVEF) 28±7% (mean±SD). The procedure was successful in all with no serious complications Clinical composite score improved at 6 months in 65%, and worsened in 35%. LVEF improved >5% in 88%, from 28±7% to 41±9%. 6-minute walking distance improved >10% in 64%, from 248 ± 125 to 316 ± 109m. One patient suffered a lacunar ischemic stroke after 5 months with partial neurological recovery, associated with labile INRs. After 2.0±1.0 years follow-up, three patients have died, (two pneumonia, one heart failure), and two patients have suffered transient ischemic attacks. CONCLUSION: LV endocardial pacing via interventricular septal puncture in patients in whom standard CRT is not possible is similarly effective and durable, with significant but potentially acceptable risks.