The Application Of The Quadripolar Left Ventricular Lead In Cardiac Resynchronization Therapy

Objectives:Chronic heart failure is one of the difficult problems in the treatment of cardiovascular diseases. For the chronic heart failure of cardiac non-synchronization, cardiac resynchronization therapy (CRT) can effectively improve the symptoms and prognosis of patients, but there are still some problems related to complications and non response. The application experience of the foreign countries and the preliminary application results in our hospital show that the quadripolar left ventricular lead is superior to the conventional bipolar lead, and has a great clinical application prospect, so it has important practical and long-term significance. In this study, we evaluated the clinical application of the quadripolar left ventricular lead in CRT by case control.Methods:30 patients with indications for CRT were divided into quadripolar (15) and bipolar (15) patients by the left ventricular lead. Before the operation, the functional status of the patients was evaluated according to the heart function classification of New York Heart Association (NYHA). Record ECG and drug use. Left ventricular end-diastolic diameter (LVEDD), left ventricular ejection fraction (LVEF), left atrial diameter (LAD) and three-dimensional ultrasonic synchrony (16-SD) were recorded by echocardiography. The surgical procedure was performed with conventional left clavicle vein puncture. Make pouch after the success of the puncture. The coronary sinus angiography was used to select the target vessels. After implantation of left ventricular lead, the right ventricular and atrial leads were implanted respectively. Finally, the pacemaker is connected and fixed. Record the data of the electrode lead program control, left ventricular lead implantation time, X-ray exposure time and total operation time, the location of the target vessels implanted in the left ventricular lead, the post pacing ECG, the related complications and so on.1 month after the operation was performed echocardiography evaluation and optimization. The atrioventricular delay (AV Delay) and the interventricular delay (VV Delay) were optimized according to the aortic velocity time integral (AVTI). According to three-dimensional ultrasound indexes, the left ventricular synchrony in patients was evaluated by using the maximum difference of the ECG Q wave starting point of 16 myocardial segments in each segment of the minimum volume point (16-SD). The quadripolar lead group was optimized according to regulation of pacing vector. Guide patients for drug optimization. Guide patients drug optimization. The response of CRT was evaluated 6 months after operation. Follow up regularly and record the patient’s heart function, pacing program control report, electrocardiogram, echocardiography, related complications and drug use. Statistical analysis was used to compare the differences between the two groups in the aspects of safety, hemodynamics, synchronization, efficacy and complications.Results:(1) There was no significant difference between the two groups in preoperative baseline, implantation time of left ventricular lead, X-ray exposure time, total operative time, and the location of the target vessel (P>0.05). The success rate of the two groups was 100%. (2) Two groups of target vein were mostly located in the left ventricular posterior wall. The pacing vector of the quadripolar lead group is much more than that of the bipolar lead group (100.0% Vs 53.5%, P<0.01). (3) 1 month after operation, the optimized program control showed that the AVTI and 16-SD were significantly improved after optimization, and the optimization of the quadripolar lead group was better than that of the bipolar lead group (P<0.05). The results of 1 month after operation showed that there was no significant difference between the two groups in the improvement of LVEDD and LVEF (P>0.05). At 6 months postoperatively, the LVEDD of the two groups were significantly improved (P<0.05), and the LVEF of the quadripolar lead group was better than that of the bipolar lead group (P<0.05), while the LVEDD was similar in the two groups. There were 8 patients with no response to CRT in 6 months after operation, and no response of CRT was 26.67%. Among them, there are 3 cases in the quadripolar lead group and 5 cases in the bipolar lead group. There was no death case. There was no obvious difference between the two groups. (4) There were five cases of phrenic nerve stimulation (PNS) in the operations of two groups.2 cases occurred in the quadripolar lead group, and the target vessel was not adjusted by changing the pacing vector.3 cases occurred in the bipolar lead group.1 case were resolved by adjusting the original target location.2 cases were replaced by target vein. Follow up to 6 months after operation, the quadripolar lead group did not appear PNS. Bipolar lead group appeared in 2 cases of PNS,1 case of the control of the process control to reduce the output and increase the pulse width was resolved, the other 1 case through the second operation. There was no dislocation and high threshold in the two groups. Conclusions:The left ventricular quadripolar lead and the bipolar lead are equally safe. The hemodynamic, synchronism and short-term clinical effect of the quadripolar left ventricular lead is better than that of the bipolar lead. And it may help to reduce the phrenic nerve stimulation of to avoid the complications of the second operation.