Associations between neutrophil-lymphocyte ratio and monocyte to high-density lipoprotein ratio with left atrial spontaneous echo contrast or thrombus in patients with non-valvular atrial fibrillation.

BACKGROUND: The importance of inflammation in thrombosis is increasingly appreciated. Neutrophil-lymphocyte ratio (NLR) and monocyte to high-density lipoprotein ratio (MHR) are important indicators of systemic inflammation. This study aimed to investigate the associations between NLR and MHR with left atrial appendage thrombus (LAAT) and spontaneous echo contrast (SEC) in patients with non-valvular atrial fibrillation. METHODS: This retrospective, cross-sectional study enrolled 569 consecutive patients with non-valvular atrial fibrillation. Multivariable logistic regression analysis was used to investigate independent risk factors of LAAT/SEC. Receiver operating characteristic (ROC) curves were used to evaluate the specificity and sensitivity of NLR and MHR in predicting LAAT/SEC. Subgroup and Pearson correlation analyses were used to assess the correlations between NLR and MHR with the CHA2DS2-VASc score. RESULTS: Multivariate logistic regression analysis showed that NLR (OR: 1.49; 95%CI: 1.173-1.892) and MHR (OR: 2.951; 95%CI: 1.045-8.336) were independent risk factors for LAAT/SEC. The area under the ROC curve of NLR (0.639) and MHR (0.626) was similar to that of the CHADS2 score (0.660) and CHA2DS2-VASc score (0.637). Subgroup and Pearson correlation analyses showed significant but very weak associations between NLR (r = 0.139, P < 0.05) and MHR (r = 0.095, P < 0.05) with the CHA2DS2-VASc score. CONCLUSION: Generally, NLR and MHR are independent risk factors for predicting LAAT/SEC in patients with non-valvular atrial fibrillation.

Impact on right ventricular performance in patients undergoing permanent pacemaker implantation: Left bundle branch pacing versus right ventricular septum pacing.

BACKGROUND: The novel method of left bundle branch pacing (LBBP) has been reported to achieve better electrical and mechanical synchrony in the left ventricle than conventional right ventricular pacing (RVP). However, its effects on right ventricle (RV) performance are still unknown. METHODS: Consecutive patients undergoing dual-chamber pacemaker (PM) implantation for sick sinus syndrome (SSS) with normal cardiac function and a narrow QRS complex were recruited for the study. The pacing characteristics and echocardiogram parameters were measured to evaluate RV function, interventricular and RV synchrony, and were compared between ventricular pacing-on and native-conduction modes. RESULTS: A total of 84 patients diagnosed with SSS and an indication for pacing therapy were enrolled. Forty-two patients (50%; mean age 65.50 ± 9.30 years; 35% male) underwent successful LBBP and 42 patients (50%; mean age 69.26 ± 10.08 years; 33% male) RVSP, respectively. Baseline characteristics were similar between the two groups. We found no significant differences in RV function [RV-FAC (Fractional Area Change)%, 47.13 ± 5.69 versus 48.60 ± 5.83, p = .069; Endo-GLS (Global Longitudinal Strain)%, -28.88 ± 4.94 versus -29.82 ± 5.35, p = .114; Myo-GLS%, -25.72 ± 4.75 versus -25.72 ± 5.21, p = .559; Free Wall St%, 27.40 ± 8.03 versus -28.71 ± 7.34, p = .304] between the native-conduction and LBBP capture modes, while the RVSP capture mode was associated with a significant reduction in the above parameters compared with the native-conduction mode (p < .0001). The interventricular synchrony in the LBBP group was also superior to the RVSP group significantly. CONCLUSION: LBBP is a pacing technique that seems to associate with a positive and protective impact on RV performance.

Remarkable response to cardiac resynchronization therapy via left bundle branch pacing in patients with true left bundle branch block.

BACKGROUND: Left bundle branch pacing (LBBP) has been suggested as an alternative means to deliver cardiac resynchronization therapy (CRT). HYPOTHESIS: LBBP may deliver resynchronization therapy along with an advantage over traditional biventricular (BiV) pacing in clinical outcomes. METHODS: Heart failure patients who presented LBBB morphology according to Strauss's criteria and received successful CRT procedure were enrolled in the present study. Propensity score matching was applied to match patients into LBBP-CRT group and BiV-CRT group. Then, the electrographic data, the echocardiographic data and New York heart association (NYHA) class were compared between the groups. RESULTS: Twenty-one patients with successful LBBP procedure and another 21 matched patients with successful BiV-CRT procedure were finally enrolled in the study. The QRS duration (QRSd) was narrowed from 167.7 ± 14.9 ms to 111.7 ± 12.3 ms (P < .0001) in the LBBP-CRT group and from 163.6 ± 13.8 ms to 130.1 ± 14.0 ms (P < .0001) in the BiV-CRT group. A trend toward better left ventricular ejection fraction (LVEF) was recorded in the LBBP-CRT group (50.9 ± 10.7% vs 44.4 ± 13.3%, P = .12) compared to that in the BiV-CRT group at the 6-month follow-up. A trend toward better echocardiographic response was documented in patients receiving LBBP-CRT procedure (90.5% vs 80.9%, P = .43) and more super CRT response was documented in the LBBP-CRT group (80.9% vs 57.1%, P = .09) compared to that in the BiV-CRT group. CONCLUSIONS: LBBP-CRT can dramatically improve the electrical synchrony in heart failure patients with LBBB. Meanwhile, compared with the traditional BiV-CRT, it has a tendency to significantly improve LVEF and enhance the NYHA cardiac function scores.

Feasibility and stability of left bundle branch pacing in patients after prosthetic valve implantation.

BACKGROUND: Left bundle branch pacing (LBBP) has emerged as a promising pacing modality for preventing pacing induced cardiomyopathy in patients complicated with conduction abnormalities (CAs) after prosthetic valve (PV) implantation. OBJECTIVE: The present study aimed to evaluate the safety and feasibility of LBBP in this patient population. METHODS: LBBP was attempted in 20 patients complicated with atrioventricular block after PV implantation. Surface, intracardiac electrical measurements, and echocardiographic data were documented. Lead parameters and complications were routinely tracked at implantation and each follow-up visit. RESULTS: LBBP was successful in 90% (18/20) participants. The paced QRS duration and the stimulus to left ventricular activation time were 106.8 ± 6.8 ms and 65.5 ± 5.4 ms, respectively. Left bundle branch (LBB) potential was recorded in 61.1% (11/18) patients who succeeded in LBBP. During the procedure, the mean unipolar myocardium capture threshold was 0.51 ± 0.15 V@0.4 ms while the unipolar bundle capture threshold was 0.84 ± 0.51 V@0.4 ms. The mean fluoroscopic exposure time and the radiation dose were 13.0 ± 9.2 min and 81.7 ± 8.3 mGy, respectively. The average follow-up period was 10.4 ± 5.9 months (range 3-23 months). Pacing parameters remained stable and no significant lead-related complications occurred during the whole observation period. CONCLUSIONS: LBBP was safe and feasible in patients with PVs. Acceptable and stable pacing parameters could be expected during the procedure and the follow-ups.

Short-term and intermediate-term performance and safety of left bundle branch pacing.

INTRODUCTION: Left bundle branch pacing (LBBP) is a promising new method for patients with pacing indications. This study aims to evaluate the safety and feasibility of LBBP in a relatively longer time span. METHODS AND RESULTS: A total of 164 patients were recruited for LBBP in this study. Among these patients, 148 patients had pacing indications due to symptomatic bradycardia while the other 16 patients had indications for cardiac resynchronization therapy (CRT). LBBP was successful in 89.0% (146/164) of all recruited patients. Intracardiac and surface electrographic parameters and image data were documented during the LBBP procedure. The mean paced QRS duration (pQRSD) and the mean stimulus to left ventricular activation time (stim-LVAT) was 106.0 ± 12.9 ms and 64.4 ± 13.7 ms respectively. Left bundle branch (LBB) potentials were recorded in 89 patients. Forty-three of whom had sick sinus syndrome (SSS), and 46 had atrioventricular block (AVB). The presence of LBB potential was more common in patients with SSS (82.7% vs 57.5%, P = .002). No significant differences in pQRSD, stim-LVAT, or capture threshold were detected between patient groups with or without LBB potential. Patients were followed up at 1 month, 3 months, 6 months, and 1 year after the procedure. Pacing parameters and the echocardiographic data remained stable within a mean follow-up period of 8.6 ± 4.3 months. No serious complication caused by this procedure was found in this study. CONCLUSIONS: Successful LBBP carried an aspect of short pQRSD and stim-LVAT while the LBB potential was not the prerequisite and necessary feature. The LBBP procedure had a high success rate with satisfied and stable lead parameters during short and intermediate-term observations.

Evaluation of cardiac synchrony in left bundle branch pacing: Insights from echocardiographic research.

AIM: The aim of this study is to assess if left bundle branch pacing (LBBP) can preserve physiological cardiac synchrony and deliver favorable hemodynamic effects. METHODS: Consecutive patients undergoing dual chamber pacemaker implantation for sick sinus syndrome (SSS) and a normal cardiac function with a narrow QRS complex were recruited for the study. Electrocardiogram and echocardiographic examinations were performed during ventricular pacing-on and native-conduction modes. The QRS duration (QRSd), systolic dyssynchrony index (SDI), and the standard deviation of time-to-peak contraction velocity in left ventricular (LV) 12 segments (Tsd-12-LV) were measured to evaluate LV synchrony. The stroke volume (SV) and the degree of atrioventricular valvular regurgitation were also assessed. RESULTS: A total of 40 patients underwent LBBP, while another 38 patients underwent right ventricular septum pacing (RVSP) as control group. Baseline characteristics were similar between the two groups. With LBBP, the paced QRSd was slightly wider than the intrinsic QRSd (101.03 ± 8.79 ms vs 91.06 ± 14.17 ms, P < .0001) while the LV mechanical synchrony during LBBP pacing mode was similar to that of native-conduction mode (SDI, 3.14 ± 2.49 vs 2.70 ± 1.68, P = 0.129; Tsd-12-LV, 26.43 ± 15.55 vs 25.61 ± 16.07, P = .671) in the LBBP group. The LV synchrony in the LBBP group was superior to the RVSP group significantly. No significant differences in SV (64.08 ± 16.97 mL vs 65.45 ± 18.68 mL, P = .241) or the degree of atrioventricular valvular regurgitation were noted between LBBP capture and native-conduction modes. CONCLUSION: LBBP could preserve satisfactory LV synchrony and result in favorable hemodynamic effects.

Sustained localized reentry within the left atrial appendage as a mechanism of recurrent arrhythmia following atrial fibrillation ablation.

The current study investigated the electrophysiological characteristics and radiofrequency ablation in patients with localized reentry within the left atrial appendage during repeated ablation for recurrent atrial fibrillation (AF). A total of 76 patients (21 paroxysmal, 55 persistent) undergoing repeated catheter ablation for recurrent AF were enrolled in this study. Local reentry tachycardia within the left atrial appendage (LAA) was identified through combining activation and entrainment mapping. Left atriography was performed prior to radiofrequency ablation to identify the focus in the LAA. Three patients (1 paroxysmal, 2 persistent) with sustained atrial tachycardias (ATs) were identified during repeated ablation in this cohort. Combined activation and entrainment mapping were applied to localize the reentry. Postpacing interval-tachycardia cycle length differences were <30 msec at the possible site of reentry in varying segments with macro-reentry. This difference was only determined at the base of LAA for local reentry within the LAA. All 3 patients were free of atrial arrhythmias without any complications at the 6-month follow-up following the ablation in the LAA. Combining activation and entrainment mapping were necessary in approaching ATs within the LAA. Performing entrainments in opposite segments of possible loops were valuable in precluding macro-reentry. Focal ablation was safe and effective in this cohort. Therefore localized reentry within the LAA was not uncommon during repeat AF ablation. The present study may thus provide valuable information for clinicians to manage this type of arrhythmia.