Sequential versus simultaneous biventricular resynchronization for severe XXXX : evaluation by tissue Doppler imaging.

@entity1 @entity712 @entity714 @entity22286 @entity5036 @entity1562 @entity2472
BACKGROUND: Cardiac resynchronization therapy (CRT) by means of simultaneous biventricular pacing improves left ventricular systolic performance and synchrony in @entity1 with @entity712 and @entity5036 . We used tissue tracking and 3D echocardiography to evaluate the impact of sequential CRT with individualized interventricular delay programming. METHODS AND RESULTS: Twenty consecutive @entity1 with severe @entity712 and @entity714 were included. Tissue tracking and 3D echocardiography were carried out before and on the day after pacemaker implantation. Eleven different @entity22286 were examined in each @entity1 . @entity1 were reexamined after 3 months. Simultaneous CRT immediately reduced the extent of @entity1562 displaying delayed @entity2472 (DLC) from 48.6+/-16% to 23.2+/-13% (P<0.01) and increased left ventricular ejection fraction percentage (LVEF%) from 22.4+/-6% to 29.7+/-5% (P<0.01). However, optimum sequential CRT caused a further reduction in the extent of DLC from 23.2+/-13% to 11.1+/-7.2% (P<0.01), with a simultaneous increase in LVEF% (from 29.7+/-5% to 33.9+/-6%, P<0.01). Three months of optimum sequential CRT further improved LVEF% (from 33.6+/-6% to 38.6+/-7.2%, P<0.01). Tissue tracking detected the segments with DLC, and their location determined optimum interventricular delay programming. Compared with simultaneous CRT, sequential CRT increased diastolic filling time by 7+/-2.5%. CONCLUSIONS: Compared with simultaneous CRT, sequential CRT significantly improves left ventricular systolic and diastolic performance. Tissue tracking can be used to select optimum interventricular delay during CRT.
