Determination of optimal left ventricular pacing site for cardiac resynchronization therapy by tissue Doppler imaging / 上海第二医科大学学报

ABSTRACT

Objective To investigate whether the left ventricular delayed contraction site determined by tissue Doppler imaging might be an optimal left ventricular lead position for improved outcomes of cardiac resynchronization therapy (CRT) in patients with non-ischemic cardiomyopathy. Methods Thirty-three patients subjected to CRT were selected, and all were performed conventional ultrasound cardiography and tissue Doppler examinations before operation. The left ventricular delayed contraction site was determined according to the interval between the onset of QRS and the peak systolic velocity. Retrograde coronary venography was performed during operation, and the left ventricular lead site was selected according to the left ventricular delayed contraction site determined by tissue Doppler examination before operation. The coronary sinus lead site was determined under the guidance of X ray of dorsaventral, lateral, right anterior oblique and left anterior oblique positions. Patients were divided into group A(n=20, the left ventricular lead site was in line with the delayed contraction site) and group B (n=13, the left ventricular lead site was not in line with the delayed contraction site). Results There was no significant difference in age, NYHA grading, left ventricular end-systolic volume(LVESV), left ventricular ejection fraction(LVEF), pulmonary arterial systolic pressure, QRS width and Ts-SD between the two groups before operation(P> 0.05). Six months after CRT, there was no significant difference in NYHA grading, LVESV and mitral regurgitation(MR) grading between the two groups(P>0.05), while the increase in LVEF and decrease in LVESV of group A were more significant than those of group B (P<0.01). Conclusion In patients with non-ischemic cardiomyopathy, CRT significantly improves left ventricular performance, and the more favourable outcomes are achieved in those pace at the delayed contraction site. Tissue Doppler imaging may help to guide the implant of left ventricular lead.