Right ventricular lead location, right-left ventricular lead interaction, and long-term outcomes in cardiac...

The effects of right ventricular (RV) lead location and the combination of RV and left ventricular (LV) lead locations on long-term outcomes in patients receiving cardiac resynchronization therapy with defibrillator (CRT-D) are not well understood.

Our cohort consisted of 743 CRT-D patients from MADIT-CRT. We evaluated long-term death and combined heart failure or death (HF/death) in patients with non-apical RV vs. apical RV leads. We further assessed these long-term outcomes based on the combination of RV and LV leads, termed "RV-LV lead interaction." Patients with non-apical RV and apical LV leads and those with apical RV and non-apical LV leads were described to have "discordant RV and LV leads." Patients with RV and LV leads that were both non-apical or both apical were defined to have "concordant RV and LV leads."

There were no differences in death and HF/death between patients with non-apical RV vs. apical RV leads. However, patients with non-apical RV and apical LV leads had higher mortality risk, relative to those with apical RV and non-apical LV leads (HR = 4.06, 95% CI 1.73-9.53, p = 0.001) as well as those with both leads in the non-apical (HR = 3.82, 95% CI 1.33-10.98, p = 0.013) or apical (HR = 3.40, 95% CI 1.24-9.37, p = 0.018) positions. There was no difference in HF/death by RV-LV lead sub-groups.

Among CRT-D patients, long-term outcomes were similar for non-apical RV and apical RV leads. However, mortality risk was increased with discordant RV and LV leads, when a non-apical RV lead was combined with an apical LV lead.