A randomized study of haemodynamic effects and left ventricular dyssynchrony in right ventricular apical vs. high posterior septal pacing in cardiac resynchronization therapy

The effect on left ventricular (LV) systolic function and LV dyssynchrony by alternative right ventricular (RV) lead position in cardiac resynchronization therapy (CRT) is unclear. In the present study, RV apical (RV-A) was compared with RV high posterior septal (RV-HS) lead position in CRT. In 85 consecutive CRT patients (mean age 66 11 years) the RV lead placement was randomized to RV-A (n 43) or RV-HS (n 42). The LV lead was targeted to the latest activated LV segment (concordant LV lead), identified by two-dimensional speckle tracking radial strain (ST-RS) echocardiography. Concordant LV leads were obtained in 72, similar in RV-A and RV-HS (79 vs. 64; P 0.13). Six months after CRT, no difference was found in LV reverse remodelling (reduction of LV end-systolic volume epsilon 15) according to RV-A and RV-HS leads [26 (65) vs. 25 (64); P 0.93]. Superior LV reverse remodelling was observed in concordant LV leads compared with discordant LV leads [41 (73) vs. 10 (43); P 0.01]. At 6-month follow-up, LV reverse dyssynchrony (reduction of anteroseptal to posterior delay epsilon 50) using ST-RS imaging was similar in RV-A and RV-HS [25 (63) vs. 24 (62); P 0.93]. More LV reverse dyssynchrony was found in concordant LV leads vs. discordant LV leads [39 (70) vs. 10 (43); P 0.03]. A concordant LV lead was an independent predictor of LV reverse remodelling (odds ratio, 3.65; P 0.01) and LV reverse dyssynchrony (odds ratio, 4.22; P 0.02) 6 months after CRT. RV-A and RV-HS in CRT demonstrated similar LV reverse remodelling and LV reverse dyssynchrony at 6-month follow-up. Concordant LV leads provided superior LV reverse remodelling and LV reverse dyssynchrony. Trial registration: NCT01035489.