Long-term Effects Of Pacing With Right Apical Outflow Tract And Apical Pacing On Patients

Objective The study contrasted long-term effects of heart function and cardiac structure between right ventricular septum pacing and right ventricular apex pacing in patients with complete atrioventricular block,to further improve the understanding of the long-term effects of different pacemaker sites.Then provided long-term clinical evidence to guide the clinical selection of advantage pacemaker sites.Methods This is a retrospective analysed the patients with complete atrioventricular block who were implanted permanent atrioventricular double chamber pacemaker for the first time in the Department of Cardiology of the Affiliated Hospital of Qingdao University during January 2004 and December 2008.By December 2017,there were 118 cases completed the collection of medical history information.They were divided into two groups according to the location of ventricular electrode: the outflow tract septal pacing group(RVOT group)and the apical pacing group(RVA group).There were 49 cases in RVOT group with 5 of death while 69 cases in RVA group with 12 of death.A total of 102 patients underwent pacemaker replacement in the hospital during that time.The RVOT group had44 cases(female n=20,45.5%),and the RVA group had 58 cases(female n=30,51.7%).The average age at the time of pacemaker implantation was 67.44 + 8.85 years old,the average observation time was 3251.65 + 510.327 days.Compare the two groups differences between before pacemaker implantation and the cardiac pacemaker replacement,in NYHA heart function classification,left ventricular ejection fraction(LVEF),left atrial diameter(LAD),left ventricular systolic diameter(LVESD),left ventricular diastolic diameter(LVEDD),the per capita annual hospital stay because of the heart failure and the influence on mitral regurgitation.The subgroup analysis of the changes in the NYHA heart function classification,LVEF,LAD,LVESD,LVEDD was carried out by the sex,the age and the grade of NYHA classification.According to the subgroup analysis of NYHA classification,the EF value of the patients with poor initial cardiac function(grade Ⅱ)in the apical pacing group was significantly lower than that in the pacemaker replacement group.Results There was no significant difference in all-cause mortality between the two groups during the study period,and the mortality of heart failure in RVOT group was lower than that in RVA group.Group RVOT after implantation of NYHA classification,LVEF,LVESD,LVEDD and the change of per capita hospitalization days were better than that of RVA group,and the left atrial size,mitral regurgitation was not statistically significant.According to the subgroup analysis of age and sex,there was no significant difference in the subgroup analysis of NYHA grade,LVEF,LAD,LVESD,LVEDD after implantation.Conclusion Right ventricular outflow tract septum pacing can reduce heart failure mortality compared with interventricular pacing.In the long-term influence,Right ventricular outflow tract septum pacing can reduce the damage to cardiac systolic function and ventricular structure changes,and also reduce hospitalization for heart failure.Pacing at the same pacing site patients in different age or sex does no different affect.Therefore,age and sex are not the reference basis for the selection of dominant pacing sites.The NYHA classification of cardiac function before pacemaker installation can be used as the basis for the selection of dominant pacing sites.Patients with poor cardiac function should benefit from ventricular septal pacing.