Feasibility and safety of new simplified left bundle branch area pacing via nine-partition method / 中华心血管病杂志

Objective: To investigate the efficacy and safety of left bundle branch area pacing (LBBaP) with the new simplified approach (nine-partition method). Methods: A total of 118 patients with clinical indications and received pacemaker implantation from December 1, 2018 to December 31, 2019 in Beijing Anzhen Hospital were enrolled. LBBaP was performed with the nine-partition method (in the right anterior oblique 30° position, the ventriculogram was divided into nine partitions and the initial implant sites were located in the lower base 1/3 partitions). In X-ray image, the 3830 lead is located in the left bundle branch area, the unipolar pacing QRS wave is in the form of right bundle branch block, and the peak time from stimulation to left ventricular activation<90 ms is defined as successful operation. The clinical characters, such as the methods of venipuncture, electrode parameters, operation duration, fluoroscopy duration, the peak time from stimulation to left ventricular, pacemaker types, surgical success rate, complications, and immediate postoperative ECG parameters were collected. The patients were followed up after the operation, and the electrode parameters and postoperative complications were recorded. Results: This study is a retrospective study. There were 62 (52.5%) male patients in this cohort, the average age was (65.9±13.4) years old,and there were 49(41.5%) sick sinus syndrome, 6(5.1%) abnormal sinus node and atrioventricular node simultaneously, 63(53.4%) atrioventricular block, 26(22.0%) atrial fibrillation, 20(16.9%) cardiomyopathy; the baseline duration of QRS was (109.21±39.03) ms. Successful LBBaP was achieved in 109 patients with"nine-partition method"and the success rate was 92.4%; 104 patients (95.5%) were axillary vein puncture, 5 (4.6%) were subclavian vein puncture; the operation duration was (80.3±23.0) min, the fluoroscopy duration was (12.29±5.13) min; the QRS duration after LBBaP was (116.36±18.11) ms. The threshold of the left bundle branch (LBB) lead was (0.92±0.63) V, the R wave amplitude was (10.60±5.04) mV and the impedance was (798.71±194.90) Ω. In 1 V pacing, the peak time from stimulation to left ventricular activation was (67.91±12.15) ms, and in 5 V pacing was (67.52±12.45) ms; 1 case (0.9%) with a single-chamber pacemaker implanted, 106 cases (97.3%) with dual-chamber pacemaker and 2 cases (1.8%) with three-chamber pacemakers. There were no hematomas, pneumothorax, hemothorax, electrode dislocation, infection, and capsular hemorrhage and other serious surgery-related complications during the operation. A total of 97 patients (89.0%) were followed up for (6.21±2.90) months. The electrode parameters of all patients were stable and no complications observed. Conclusions: The LBBaP with nine-partition method is a simple, safe and effective physiological pacing approach. However, its long-term effect still needs to be further verified.

Evaluation of cardiac synchrony in patients with permanent left bundle branch area pacing by tissue Doppler imaging / 中华超声影像学杂志

Objective To compare and analyze the synchrony of cardiac contraction when left bundle branch area pacing ( LBBP ) using tissue Doppler imaging ( TDI ) . Methods T wenty‐four patients with LBBP and 20 patients with right ventricular pacing ( RVP ) were enrolled in the study . Among them , 35 cases were diagnosed as sick sinus syndrome ( SSS ) and 9 cases were diagnosed as Ⅱ or Ⅲ degree atrioventricular block ( AVB) before operation . Echocardiographic images were collected with ventricular pacemaker‐on ,and patients with SSS in LBBP group under the condition of pacemaker program control also collected the image of self‐conduction . TDI was used to measure time of the peak velocity ( T s ) of myocardial contraction in the left ventricular 12 segments ,right ventricle 2 segments ,and atrial 3 walls .The difference between the basal segment of left ventricular lateral wall and right ventricular free wall ( T s‐LV‐RV ) ,the mean value of the right ventricular 2 segments ( T s‐2‐RV ) ,the average( T s‐12‐LV ) and standard deviation ( T sd‐12‐LV ) of the left ventricular 12 segments ,and the difference in peak systolic time among 3 walls T AL‐R ,T AI‐R ,T AL‐I were calculated . Results Compared with the RVP pacing state ,the parameters of left ventricular systolic synchrony in LBBP pacing were shortened ,and the difference was statistically significant ( P ＜ 0 .05 ) . T here was no significant difference in parameters of left ventricular/right ventricular systolic synchrony and cardiac function between the LBBP group and the self‐conduction status ( P＞0 .05) . Conclusions Left ventricular systolic synchrony is superior to RVP in LBBP pacing ,and left/right ventricular systolic synchrony and cardiac function are not different from self‐conduction . LBBP is a new physiological pacing . TDI is able to quantitatively assess cardiac systolic synchrony .