Clinical outcomes of the AdaptResponse trial – Authors' reply

Abstract

whether the position of the left ventricular pacing is necessarily optimal. The left ventricular pacing lead position is important in relation to the clinical and mechanical response to CRT. Both lead placement, guided by cardiac imaging, 2 and positioning, determined by the electrical latency in intracardiac electrograms, 3 effectively improve the CRT response. The paced morphology of the electrograms recorded by the CRT device can reveal the effectiveness of the pacing. A highly effective CRT pacing rate is associated with a high prevalence of CRT responders and low risk of hospitalisation for heart failure. 4 We would like to know how the investigators determined the position of their left ventricular pacing leads for an effective adaptive CRT response. Alternatively, the investigators could have had the option of using multipolar leads, such as quadripolar leads, which do not require optimal lead positioning. Quadripolar leads are known to be associated with lower all­cause mortality than conventional bipolar leads. 5 We declare no competing interests.