[Report on initiating clinical research for electrical and mechanical synchronism of selective region pacing in the right ventricular]

To verify the electric synchronism, mechanic synchronism and hemodynamics of selective site pacing.Pacing in the right ventricular cardiac apex (RVA), the right ventricular His bundle region (His), and the septum of right ventricular high-positioned outflow tract (RVOT), CO and CI were recorded. The electrical synchronism was assessed by observing the width and shape in a 12-lead surface ECG. The mechanical synchronism was estimated by using the VVI (vector velocity imaging) technology of the Acuson Sequia 512.The results showed that CO and CI were lower while pacing in RVA, but they were not significant different (P0.05). The QRS width: (124 +/- 5.3) ms while pacing in His, (144 +/- 7.1) ms while pacing in RVOT and (156 +/- 8.6) ms while pacing in RVA. The QRS width while pacing in His and in RVOT were narrower than in RVA and there were significant differences (P0.01). Vector velocity imaging showed that mechanical synchronism was better while pacing in RVOT than that in RVA.Pacing in RVOT seems better than pacing in traditional RVA, and the operation was no more difficult than the traditional operation.