Clinical Efficacy Of Optimized Cardiac Resynchronization Therapy With Left Bundle Branch Pacing In Patients With Heart Failure Complicated With Atrioventricular Block

Objective:To compare the short-term clinical efficacy of optimized cardiac resynchronization therapy with left bundle branch pacing(Lot-CRT)and cardiac resynchronization with conventional biventricular pacing(Biv-CRT)in patients with heart failure with atrioventricular block.Methods: This is a single-center,prospective,observational study.From February 2021 to April 2022,patients with heart failure with third degree / high atrioventricular block or atrial fibrillation with atrial ventricular block were recruited in the Department of Cardiovascular Medicine of the First Affiliated Hospital of University of Science and Technology of China(Anhui Provincial Hospital)for Lot-CRT and included in Lot-CRT group.To contrast the effects of Lot-CRT and Biv-CRT,tendentious score 1:1to match the patients who met the enrollment criteria underwent Biv-CRT and included in Biv-CRT group,collected baseline data,surgical data and postoperative follow-up,and analyzed the improvement of conventional ECG,echocardiography,pacing parameters.Echocardiographic indicators include left ventricular ejection fraction(LVEF),left atrial diameter(LAD),left ventricular internal diastolic diameter(LVEDD),left ventricular interal diameter(LVESD),left ventricular systolic end volume(LVESV),left ventricular systolic end volume(LVEDV),mitral regurgitation(MR),tricuspid regurgitation(TR),etc.To evaluate the safety and efficacy of Lot-CRT and Biv-CRT.Results:(1)19 patients were planned to be enrolled,and 16 patients finally successfully completed Lot-CRT.16 patients who received Biv-CRT in the same time period were matched in a 1:1 ratio by tendentious score.During follow-up,there were no deaths in the two groups,and no postoperative complications such as subcutaneous hematoma,lead displacement and ventricular septal perforation occurred.(2)16 patients have finally successfully completed Lot-CRT,including 10 men(62.50%),6 women(37.50%),mean age(70.50 ± 12.38).After treatment,the QRS duration at 6 months was shorter than preoperative(150.40±34.23 ms vs 126.31 ± 28.30)and there was no significant difference between the immediate QRS duration(126.31±28.30 ms vs 126.87±29.20ms).Intraoperative and postoperative threshold,impedance,perception(1.17± 0.49 V /0.24 ms vs 1.08± 0.39 V /0.24 ms,P=0.608;622.50±128.97Ωvs 609.38±121.63Ω,P=0.072;9.38±1.59 m V vs 9.50±1.55 m V,P=0.059).During the follow-up period,the results showed that LVEF increased from baseline 43.19 ± 7.77% to 54.94±6.42%(P< 0.00 l),and LVEDV decreased from baseline 189.00±60.79 mm to 158.00±49.98mm(P<0.001),with statistical differences.LVEDD,LVESD,LAD,LVEDV,TR,and MR decreased from preoperative conditions,but the difference was not significant.(3)After 6 months of follow-up,compared with Biv-CRT group,the reduction of QRS was more obvious in Lot-CRT group(126.87±29.20 ms vs 146.20±19.64 ms,P<0.001),and the improvement of NYHA cardiac function was more obvious(1.88±0.50 vs 2.06±0.85,P<0.001).LVEF increased to higher(54.94±6.42 vs46.75±15.12%,P<0.001),LVEDV decreased to smaller(158.00±49.98 ml vs175.19±50.28 ml,P<0.05).Conclusion: Lot-CRT is safe and effective,with stable pacing parameters,which can shorten the QRS time limit,improve the left ventricular ejection fraction.Not inferior to conventional CRT in improving patient cardiac function.