Personalized pulmonary vein isolation with very high-power short-duration lesions guided by left atrial wall thickness: the QDOT-by-LAWT randomized trial.

AIMS: Pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF) using very high-power short-duration (vHPSD) radiofrequency (RF) ablation proved to be safe and effective. However, vHPSD applications result in shallower lesions that might not be always transmural. Multidetector computed tomography-derived left atrial wall thickness (LAWT) maps could enable a thickness-guided switching from vHPSD to the standard-power ablation mode. The aim of this randomized trial was to compare the safety, the efficacy, and the efficiency of a LAWT-guided vHPSD PVI approach with those of the CLOSE protocol for PAF ablation (NCT04298177). METHODS AND RESULTS: Consecutive patients referred for first-time PAF ablation were randomized on a 1:1 basis. In the QDOT-by-LAWT arm, for LAWT ≤2.5 mm, vHPSD ablation was performed; for points with LAWT > 2.5 mm, standard-power RF ablation titrating ablation index (AI) according to the local LAWT was performed. In the CLOSE arm, LAWT information was not available to the operator; ablation was performed according to the CLOSE study settings: AI ≥400 at the posterior wall and ≥550 at the anterior wall. A total of 162 patients were included. In the QDOT-by-LAWT group, a significant reduction in procedure time (40 vs. 70 min; P < 0.001) and RF time (6.6 vs. 25.7 min; P < 0.001) was observed. No difference was observed between the groups regarding complication rate (P = 0.99) and first-pass isolation (P = 0.99). At 12-month follow-up, no significant differences occurred in atrial arrhythmia-free survival between groups (P = 0.88). CONCLUSION: LAWT-guided PVI combining vHPSD and standard-power ablation is not inferior to the CLOSE protocol in terms of 1-year atrial arrhythmia-free survival and demonstrated a reduction in procedural and RF times.

Personalized pulmonary vein antrum isolation guided by left atrial wall thickness for persistent atrial fibrillation.

AIMS: Pulmonary vein (PV) antrum isolation proved to be effective for treating persistent atrial fibrillation (PeAF). We sought to investigate the results of a personalized approach aimed at adapting the ablation index (AI) to the local left atrial wall thickness (LAWT) in a cohort of consecutive patients with PeAF. METHODS AND RESULTS: Consecutive patients referred for PeAF first ablation were prospectively enrolled. The LAWT three-dimensional maps were obtained from pre-procedure multidetector computed tomography and integrated into the navigation system. Ablation index was titrated according to the local LAWT, and the ablation line was personalized to avoid the thickest regions while encircling the PV antrum. A total of 121 patients (69.4% male, age 64.5 ± 9.5 years) were included. Procedure time was 57 min (IQR 50-67), fluoroscopy time was 43 s (IQR 20-71), and radiofrequency (RF) time was 16.5 min (IQR 14.3-18.4). The median AI tailored to the local LAWT was 387 (IQR 360-410) for the anterior wall and 335 (IQR 300-375) for the posterior wall. First-pass PV antrum isolation was obtained in 103 (85%) of the right PVs and 103 (85%) of the left PVs. Median LAWT values were higher for PVs without first-pass isolation as compared to the whole cohort (P = 0.02 for left PVs and P = 0.03 for right PVs). Recurrence-free survival was 79% at 12 month follow-up. CONCLUSION: In this prospective study, LAWT-guided PV antrum isolation for PeAF was effective and efficient, requiring low procedure, fluoroscopy, and RF time. A randomized trial comparing the LAWT-guided ablation with the standard of practice is in progress (ClinicalTrials.gov, NCT05396534).

Un nuevo método no invasivo en la valoración integral de la fibrilación auricular por tomografía cardíaca / A novel, non-invasive, integral imaging assessment in atrial fibrillation by cardiac tomography

Resumen Objetivo: Analizar la utilidad clínica y la viabilidad de la tomografía cardíaca multidetector (TCMD) en la valoración de pacientes con fibrilación auricular (FA). Material y métodos: Estudio prospectivo de casos y controles en 84 sujetos (54 con FA y 30 controles). La morfología de la orejuela izquierda (OI) se clasificó en cactus, ala de pollo, manga de viento y coliflor. La presencia de trombo en la OI, el antecedente de accidente cerebrovascular y la escala CHA2DS2-VASc se compararon con parámetros obtenidos por TCMD. Resultados: La fracción de expulsión de la aurícula izquierda (FEAI) y la fracción de expulsión de la orejuela izquierda (FEOI) fueron más bajas en los individuos con FA (p < 0.001). El volumen indexado de la aurícula izquierda (VIAI) fue mayor en los pacientes con FA (p < 0.001). Se observó una correlación inversa entre la FEAI y el VIAI (r = -0.38, p < 0.001). La morfología tipo coliflor fue la más frecuente en enfermos con FA, mientras que la de tipo cactus predominó en los controles. La de tipo coliflor fue la más relacionada con presencia de trombos (p < 0.01), así como una calificación CHA2DS2-VASc alta. La velocidad de flujo fue menor en los pacientes con FA (p < 0.001). Conclusión: La TCMD es un método novedoso y no invasivo para una valoración integral en la FA. Los resultados de este estudio podrían mejorar la precisión, la utilidad clínica y el análisis de estratificación del riesgo en la FA. Los autores proponen incluir este nuevo método en la valoración integral del riesgo tromboembólico en pacientes con FA.

Abstract Objective: To analyze the clinical utility and feasibility of the multidetector cardiac tomography (MDCT) in multi-parametric imaging assessment in atrial fibrillation (AF) patients. Material and methods: Prospective case-control study in 84 subjects (54 AF subjects and 30 healthy subjects). Left atrial appendage (LAA) morphology was classified as: cactus, chicken wing, wind sock, cauliflower. Intra-cardiac thrombus, stroke history and CHA2DS2-VASC scale were compared to cardiac MDCT atrial imaging assessment. Results: Left atrial ejection fraction (LAEF) and LAA ejection fraction (LAAEF) were lower in AF subjects (p < 0.001), left atrial volume index (LAVI) was higher in AF subjects (p < 0.001). An inverse correlation between LAEF and LAVI was found (r = −0.38, p < 0.001). Cauliflower LAA morphology frequency was higher in AF subjects, whereas cactus LAA morphology frequency was higher in controls. Cauliflower LAA morphology was associated with thrombus presence (p < 0.01) as well as a higher CHA2DS2-VASc score. Flow velocity were lower in AF subject compared to controls (p < 0.001). Conclusion: MDCT is a novel, non-invasive, worldwide available method for an integral assessment in AF. Our results could improve precision, clinical utility and risk stratification analysis in AF. Our proposal is to include this new method into the global cardiovascular and thrombotic risk assessment in AF patients.