Haemodynamic vector personalization of a quadripolar left ventricular lead used for cardiac resynchronization therapy: use of surface electrocardiogram and interventricular time delays

Aims The choice of left ventricular pacing configurations (LVPCs) of quadripolar leads used for cardiac resynchronization therapy (CRT) affects haemodynamic response and thus may be a tool for device optimization. The value of surface electrocardiograms and interventricular time delays (IVDs) for optimization is unknown. Methods and results Sixteen patients implanted with a CRT device with a quadripolar LV lead underwent invasive testing of LV dP/dt. QRS durations at baseline (bl) and during biventricular pacing (biv) were measured using different LVPCs (total of 141 LVPCs; 8.8 per patient). Variations in QRS duration during biv were calculated for each patient (Delta QRS) and, when compared with intrinsic QRS duration, for all LVPCs (Delta QRS(LVPC)). Interventricular time delays between the poles of the LV lead were obtained from intracardiac electrograms. Delta IVD was calculated as IVDmax - IVDmin. Parameters were correlated with LV dP/dt. Delta QRS and Delta QRS(LVPC) both significantly correlated with LV dP/dt (P < 0.01). Correlation was found for patients with ischaemic (P < 0.001) and non-ischaemic cardiomyopathy (P < 0.05), and for patients with bl QRS duration >168 ms (P < 0.001), but not,168 ms (P = ns). The LVPC with shortest QRS duration also yielded maximal LV dP/dt in 6 of 16 patients (37.5%), and was equal or better in LV dP/dt in 12 of 16 patients (75%). Delta IVD neither correlated with Delta QRS nor Delta LV dP/dt. Conclusion Delta QRS predicts the maximal value of vector personalization in the individual. Reductions inQRS width, but not IVDs, correlate with acute haemodynamic response. Intraindividually, in 75% of patients, the LVPC with the shortest QRS duration gives equal or superior haemodynamic results when compared with the LVPC with longest QRS duration.