Noninvasive Imaging of Cardiac Venous Anatomy With 64-Slice Multi-Slice Computed Tomography and Noninvasive Assessment of Left Ventricular Dyssynchrony by 3-Dimensional Tissue Synchronization Imaging in Patients With Heart Failure Scheduled for Cardiac Re

Objectives of this study were to perform a prospective head-to-head comparison between multi-slice computed tomography (MSCT) venography and invasive venography in cardiac resynchronization therapy (CRT) candidates as well as to evaluate the relation between left ventricular (LV) lead position and effect on LV dyssynchrony and immediate response to CRT. Twenty-one consecutive heart failure patients scheduled for CRT implantation were prospectively enrolled to undergo 64-slice MSCT to visualize the venous system, invasive venography during device implantation, and tri-plane tissue synchronization imaging (TSI) before and after implantation. Excellent agreement between MSCT and invasive venography was noted. No significant differences were observed between both techniques regarding vessel diameters. In 12 patients, a match was observed between the area of latest mechanical activation (on TSI) and LV lead position. These patients showed a significant decrease in LV dyssynchrony (43 ± 7 ms to 11 ± 9 ms, p <0.0001) with acute reduction in LV end-systolic volume (188 ± 54 ml to 162 ± 48 ml, p <0.01) and improvement in LV ejection fraction (22% ± 9% to 34% ± 9%, p <0.01). Patients with a mismatch between area of latest activation and LV lead position remained dyssynchronous without improvement in LV function. In conclusion, visualization of major tributaries of the coronary sinus was comparable between invasive venography and MSCT venography. Optimal LV lead positioning in a vein draining the area of latest mechanical activation (determined from tri-plane TSI) resulted in acute improvement of LV dyssynchrony and systolic function after CRT implantation.