Search

Background: Pulmonary vein isolation is the cornerstone of catheter ablation in patients with atrial fibrillation (AF). However, with advanced left atrial (LA) structural changes, additional targeted catheter ablation of low‐voltage zones (LVZs) has produced favorable results. Therefore, with the advent of single‐shot techniques, it would be helpful to predict the presence of LVZs before an ablation procedure. Objective: We hypothesized that computed tomography (CT)‐derived left atrial volume index (LAVI), in combination with other objective parameters, could be used to develop a score able to predict the presence of LVZs. Methods: In a large cohort of patients undergoing their first AF ablations, comprehensive echocardiographic evaluations and cardiac CT were performed. During the electrophysiological studies, LA geometry and electroanatomic voltage maps were created. LVZs were defined as areas ≥1 cm2 with bipolar peak‐to‐peak voltage amplitudes ≤0.5 mV. Results: In a derivation cohort of 374 patients, predictors of LVZs were identified by regression analysis and used to build the Zentralklinik Bad Berka and University of L'Aquila (ZAQ) score (age ≥65 years; female sex; and CT‐LAVI ≥57 mL/m2). The ZAQ score of 2 points accurately identified the presence and the extent of LVZs (area under the curve [AUC], 0.809; 95% confidence interval [CI], 0.758‐0.861; P <.001 and 3 [interquartile range, IQR, 1.5‐4.5] vs 7 cm2 [IQR 4‐9]; P =.001). In a validation cohort of 103 patients, the predictive value of the score was confirmed (AUC, 0.793; 95% CI, 0.709‐0.878; P <.001 and 4 [IQR, 2‐7] vs 11.5 cm2 [IQR, 8‐16.5]; P =.001). Conclusions: The ZAQ score identifies LVZs and may be useful for planning the ablation strategy ahead of time. [ABSTRACT FROM AUTHOR]

Multipoint LV Pacing Improves Mid-Term CRT Response Introduction Cardiac resynchronization therapy (CRT) with multipoint left ventricular (LV) pacing in a single coronary sinus branch improves acute LV function. We hypothesized that multipoint pacing (MPP) can improve midterm echocardiographic and clinical response compared with conventional CRT. Methods and Results Consecutive patients receiving a CRT implant (Unify Quadra MP™ or Quadra Assura MP™ CRT-D and Quartet™ LV lead, St. Jude Medical, Sylmar, CA, USA) were randomized to receive biventricular (BiV) pacing with either conventional LV pacing (CONV group) or MPP (MPP group). For each patient, an optimal pacing configuration for the assigned pacing mode was programmed based on intraoperative pressure-volume (PV) loop measurements. A clinical evaluation and transthoracic echocardiogram were performed before implant (BASELINE) and at 3 months postimplant and analyzed by a blinded observer. A reduction in end-systolic volume (ESV) of ≥15% relative to BASELINE was prospectively defined as response to CRT. Forty-four patients (NYHA Class III, EF 29 ± 6%, QRS duration 152 ± 17 milliseconds) were enrolled and randomized. One patient in the MPP group was lost to follow-up and excluded from further analysis. After 3 months, 11 of 22 (50%) CONV patients and 16 of 21 (76%) MPP patients were classified as responders. ESV reduction, EF increase, and NYHA class reduction relative to BASELINE were significantly greater in the MPP group than in the CONV group (ESV: −21.0 ± 13.9 vs. −12.6 ± 11.1%, P = 0.03; EF: +9.8 ± 5.1 vs. +2.0 ± 7.8 percentage points, P < 0.001; ΔNYHA: −1.05 ± 0.22 vs. −0.72 ± 0.46 functional classes, P = 0.006). Conclusion PV loop optimized BiV pacing with MPP resulted in an improved rate of response to CRT. [ABSTRACT FROM AUTHOR]