The Feasibility Of Achieving Cardiac Resynchronization Therapy Base On Right Atrial-left Ventricular Interval With Dual Chamber Pacemaker

Objective:To explore the feasibility of achieving cardiac resynchronization therapy base on Right atrial-Left ventricular(RAS-LVS)interval optimized Atrial-ventricular interval in congestive heart failure(CHF)patients planted with dual chamber pacemaker.Methods:Selected from admitted to the First Affiliated Hospital of Kunming Medical University,in line with ACC/AHA guidelines CRT I class indications and successfully implanted dual chamber pacemaker in patients with chronic congestive heart failure 11 cases.Patients who met the inclusion criteria entered the study.According to RAS-LVS interval by measured after the extended atrial-ventricular integral(AVI),optimize AVI base on this interval in the echocardiographic index and under the monitoring of duration of QRS,left ventricular ejection fraction(LVEF),standard deviation of time intervals of the 12 left ventricular segments(Ts-SD12),duration of QRS complex,aortic valvula velocity time integral(AVVTI),interventri-cular mechanical delay(IVMD),mitral regurgitation area(MRA),and above of all were compared between pre-and post operation with dual chamber pacemaker.Calculation of left ventricular priority coefficient(?= the optimization of AVI/RAS-LVS interval).Results:The duration of QRS complex(135±11ms vs 187±21ms,P<0.05),MRA(3.10±1.12cm2 vs 4.28±1.25cm2,P<0.05),IVMD(65.2±11.29ms vs 82.64±14.74ms,P<0.05),were significantly less than that's of pre-operation.AVVTI(22.84±2.15cm vs 16.43±2.31cm,P<0.05)and LVEF(37.2±3.88%vs 27.61 ±4.20%,P<0.05)were greater than that's of pre-operation.Conclusions:It can achieve Cardiac resynchronization therapy base on RAS-LVS interval in CHF patients planted with dual chamber pacemaker,and the most suitable AVI is 55%of RAS-LVS interval.