Safety and efficiency of pacing at right ventricular outflow versus at ventricular cardiac apex / 中华心血管病杂志

<p><b>OBJECTIVE</b>To compare the safety and efficiency of pacing at right ventricular outflow versus right ventricular apex.</p><p><b>METHOD</b>Patients were divided into two groups: pacing at ventricular cardiac apex (common pacing group, n = 22) and pacing at right ventricular outflow tract (uncommon pacing group, n = 18).</p><p><b>RESULTS</b>Impedance and amplitude of R-wave were similar during implantation between the two groups (all P > 0.05). The pacing threshold and electric current were significant higher in uncommon group than those in common pacing group (all P < 0.05), however, these differences disappeared at 1 month post pacemaker implantation (all P > 0.05). The mean QRS duration tended to be shorter in uncommon pacing group compared to that in common pacing group (P > 0.05). There was no pacemaker associated adverse effect in both groups.</p><p><b>CONCLUSION</b>The safety and efficiency of pacing at right ventricular outflow was similar as those of pacing at right ventricular apex.</p>

Report on initiating clinical research for electrical and mechanical synchronism of selective region pacing in the right ventricular / 中华心血管病杂志

<p><b>OBJECTIVE</b>To verify the electric synchronism, mechanic synchronism and hemodynamics of selective site pacing.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>The results showed that CO and CI were lower while pacing in RVA, but they were not significant different (P>0.05). 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 (P<0.01). Vector velocity imaging showed that mechanical synchronism was better while pacing in RVOT than that in RVA.</p><p><b>CONCLUSION</b>Pacing in RVOT seems better than pacing in traditional RVA, and the operation was no more difficult than the traditional operation.</p>