The Research On The Single Left Ventricular Pacing By Rate Adaptive AV Delay To Achieve The Systolic Resynchronization

Graduate student:Zhao Lulu Tutor:Zhao Ling Pu LijingPurposeIn this study, a dual-chamber pacemakers use single left ventricular pacing though rate adaptive AV delay to realize CRT which track the right physiological PR interval, to clarify that dual-chamber pacemaker therapy CHF efficacy with rate adaptive AV delay is superior or alternatively the three-chamber pacemakers which are widely used.MethodSelected from May 2013 to March 2015 admitted to the First Affiliated Hospital of Kunming Medical University, in line with ACC/AHA guidelines CRT Ⅰ class indications and successfully implanted CRT-P/D in patients with chronic congestive heart failure 64 cases, including Dilated Cardiomyopathy in 54 cases,10 cases of Ischemic Cardiomyopathy. Patients who met the inclusion criteria entered the study, given optimal medical therapy and implantation of a pacemaker, selected 32 patients who used single left ventricular pacing by rate adaptive AV delay to realize cardiac resynchronization group as the study group, according to baseline data to evaluate the situation, in strict accordance with a gender, NYHA classification, heart failure reason, QRS interval, etc, the 32 patients of the standard biventricular pacing ground to realize cardiac resynchronization therapy as the control group. After the successful clinical match,the patients went to the research and the clinical follow-up. Patients in the study group used the echocardiography index and electrocardiogram QRS duration to monitor, taking into account the premise of the atrioventricular node, set the current maximum of the aortic blood flow velocity time integral (AVVTI), left ventricular ejection fraction (LVEF), and refer the separation of the E, A peak, the minimum of the mitral regurgitation area, the narrowest QRS duration on electrocardiogram corresponding AV delay (AVD) for the optimization AVD.We based on the Holter to collect the relationship between the heart changes and the PR interval changes, thanset the optimum individualized AV delay (AVD), and programmed into the pacemaker and open rate adaptive AV delay that allows the rate adaptive AV delay single ventricular pacing group keeps track of the left AVD physiological right atrioventricular the PR interval. The patients who implanted standard double ventricular pacing pacemaker used the echocardiography indexes and QRS duration to monitor and to optimize the pacemaker. In the clinical follow-up, the two groups need the follow-up after 1-.3 and 6 months,and 1 year. We needed to compare Holter QRS wave duration,and cardiac ultrasound echocardiographic evaluation index [twelve segments peak time standard deviation (TS-SD12), the main pulmonary artery before ejection time difference (IVMD)], blood flow before EA peak spacing, aortic velocity time integral (AVVTI), the maximum change rate of left ventricular pressure (MRdp/dt) and conventional echocardiographic indicators (left ventricular end-diastolic diameter, left ventricular ejection fraction and mitral regurgitation area, etc.), while the NYHA grade of cardiac function,6-minute walk test, Minnesota Heart Failure Quality of Life (MN), readmission rates and survival rates,etc. to clarify that dual-chamber pacemaker therapy CHF efficacy with rate adaptive AV delay is superior or alternatively the three-chamber pacemakers which are widely used.Using SPSS 17.0 statistical analysis of the data package, P<0.05 was considered statistically significant sentence.Result1. In the study, the average follow-up was 7.86±3.67 (months), rate adaptive AV delay by single left ventricular pacing group,32 patients were implanted dual chamber pacemaker (left ventricular+right atrium) or plant the three-chamber pacemaker (left ventricular+right ventricle+right atrium)which closed the right ventricular pacing function, reservations perception and defibrillation capabilities, standard dual chamber pacing group of 28 patients implanted CRT-D and 4 cases implantation of CRT-P, no major surgical complications, pacemaker can work properly. Rate adaptive AV delay by single ventricular pacing group was significantly shorter programmed to optimize the time required for standard biventricular pacing group (20.00±4.00min and 52.00±8.00min, P<0.001), CRT life expectancy by frequency adaptive AV delay longer single ventricular pacing group (7.80±030 years and 4.50±0 20 years, P<0.0001.), minimum 7.50 years, up to 8.10 years;expected annual treatment costs through rate adaptive AV delay single ventricular pacing group lower (13000±1000yuan and 22000±2000 yuan, P<0.001).2. The optimal AV delay period of rate adaptive AV delay by single left ventricular pacing group was 120.60-140.00ms, longer than the standard biventricular pacing group (105.00-121.00ms), the difference was statistically significant (P<0.05).3. The QRS wave duration in patient of the rate adaptive AV delay by single left ventricular pacing group was shorter than the standard biventricular pacing group (136.00±10.00ms and 142.00±11.00ms, P<0.05); the frequency adaptive Room Delayed single ventricular chamber pacing group, the followed-up QRS duration was significantly shorter than the preoperative (136.00±10.00ms and 188.00±21.00ms, P<0.05).4. Cardiac resynchronization indicators,the interventricular mechanical delay time in the rate adaptive AV delay by single left ventricular pacing group is shorter than the standard biventricular pacing group (64.20±12.80ms and 72.30±13.60, P<0.05), the difference was statistically significant; EA peak period (208.00±56.00 and 220.00±52.00, P> 0.05), left ventricular 12-segment peak time standard deviation (87.00±21.00 and 98.00±.26.00, P> 0.05), the difference was not statistically significant.5. The AVVTI in the rate adaptive AV delay by single left ventricular pacing group is bigger than the data in the standard biventricular pacing group (21.80±2.30cm and 20.60±2.10cm, P<0.05), mitral regurgitation area is smaller (3.10±110 cm2 and 3.70±1.20 cm2, P<0.05), the differences were statistically significant; between the two groups of left ventricular end-diastolic diameter (67.20±10.90mm and 70.30± 10.50mm, P> 0.05), left ventricular ejection fraction (35.00±4.00% and 34.00± 3.00%, P> 0.05),differences were not statistically significant.6. The 6-minute walk test datas in the two groups were 515.00±58.00m and 490.00± 46.00m, P> 0.05; Minnesota quality of life scores in two groups were 27.96±10.77 points and 25.71±15.93points, P> 0.05, the differences were not statistically significant.In conclusion① The rate adaptive AV delay by single left ventricular pacing can realize the cardiac resynchronization therapy more physiological, safety, and feasibl, comparing with the traditional cardiac resynchronization therapy② The rate adaptive AV delay by single left ventricular pacing can realize the cardiac resynchronization therapy can improve the clinical symptoms of heart failure, the acute echocardiography hemodynamic index, the effect is not inferior to standard biventricular pacing.③ The rate adaptive AV delay by single left ventricular pacing can realize the cardiac resynchronization therapy can prolong battery life, reduce treatment costs, simplify pacemaker optimization program, with promotion prospects.