Analysis Of The Necessity Of Right Ventricular Backup Electrode In Permanent His Bundle Pacing

Objective Evaluating the necessity of the right ventricular backup electrode in His bundle pacing(HBP)patients who need high ratio ventricular pacing.Methods We enrolled all the patients successfully underwent permanent his bundle pacing in cardiology department of The General Hospital of Shenyang Military Region from Mar.2016 to Dec.2017.Patients who pacing tested by 5.0V/0.5ms after surgery showed selected his bundle pacing(SHBP)were implanted a right ventrical(RV)backup electrode;Patients who pacing tested by 5.0V/0.5ms after surgery showed non-selected his bundle pacing(NSHBP)also be implanted a right ventrical backup electrode,when their RV pacing threshold is higher than 1.5V/0.5ms;otherwise,NSHBP patients.whose RV pacing threshold is lower than 1.5V/0.5ms,didn't implanted a right ventrical backup electrode.Patients who asked for a right ventrical backup electrode were all implanted.We designed a self-control study to compare their HBP capture threshold and RV capture threshold for NSHBP between intraoperative and postoperative followed up,what's more.RV backup electrode work status were observed.Results Among the 82 patients who need high ratio ventricular pacing,25 patients are atrial fibrillation(AF)with slow ventricular rate patients,and the others are advanced AV block patients with narrow QRS complex.ALL the 28 SHBP patients were implanted RV back up electrode,while only 8 in 54 NSHBP patients implanted.82 patients' HBP average capture threshold post operation was 1.19V±0.86V/0.5ms,and 2 patients need higher capture threshold more than 2.5V/0.5ms at implantation.All the 28 SHBP patients average HB capture threshold was 1.22±0.85V/0.5ms,while NSHBP group is 1.17 ± 0.81V/0.5ms.RV average capture threshold of the 54 NSHBP patients was 0.86mV±0.15mV.Separately,1 month.3 months,6 months and 12 months average HBP capture threshold of the 28 SHBP patients was 1.20±0.82V/0.5ms?1.22±0.83 V/0.5ms?1.23±0.86V/0.5ms?1.25±0.79V/0.5ms,there were no difference between the followed lm/3m/6m/12m postoperative and intraoperative after paired t test(P>0.05).Average HB capture threshold of the 54 NSHBP patients at each follow up time was 1.18±0.79V/0.5ms?1.20±0.83V/0.5ms?1.22 ± 0.88V/0.5ms?1.24±0.82V/0.5ms.while RV capture threshold,separately,was 0.85V±0.52V/0.5ms?0.89V ± 0.53V/0.5ms?0.93V ±0.61 V/0.5ms?0.92V±0.52V/0.5ms,which showed a negative result too(P>0.05).During the whole 12 months follow up,a significant increase(>1.0V/0.5ms)in HB pacing thresholds occurred in 4 patients,but only 1 patient in SHBP group(3.6%)recorded RV back up electrode pacing,and pacing ratio was less than 1%.No pacing record was recorded in 8 NSHBP patients who implanted RV back up electrode.There was no lead dislodgment during follow-up and no complication related to HBP procedure in the all 82 patients.Conclusion Permanent his bundle pacing is feasible safety and stable.RV back up electrode is not essential for NSHBP patient who has an acceptable HBP and RV capture threshold in the operation;while it is recommended for all SHBP patients in our center.