Long-term follow-up of atrioventricular delay optimization in patients with biventricular pacing

Abstract

Background: Atrioventricular (AV) delay optimization may be important in patients with biventricular pacing and the optimal AV delay can be predicted using Doppler echocardiography and the formula: optimal AV delay = AV delay-the interval between the end of A wave and complete closure of the mitral valve when the AV delay is set at slightly prolonged AV delay. Methods and Results: In the present study the efficacy of this method was evaluated in 5 patients (67.4±8.0 (SD) years old) with biventricular pacing. Cardiac output (CO) and diastolic filling time were measured by Doppler echocardiography. When the AV delay was set at the predicted optimal AV delay -25 ms, the predicted optimal AV delay (133±66 ms) and predicted optimal AV delay +25 ms, the respective CO were 4.5±0.9, 5.3±1.0, 4.8±1.0 L/min (p<0.05, ANOVA) and the diastolic rilling times were 364±100, 373±105, 335±84 ms (p<0.05, ANOVA). Congestive heart failure improved from New York Heart Association class 3.6±0.5 to 1.4±0.5 (p<0.001). Conclusions: AV delay optimization is important in patients with biventricular pacing and can be easily achieved by the new method.