A comprehensive multi-index cardiac magnetic resonance-guided assessment of atrial fibrillation substrate prior to ablation: Prediction of long-term outcomes.

Multiple cardiac magnetic resonance (CMR)-derived indices of atrial fibrillation (AF) substrate have been shown in isolation to predict long-term outcome following catheter ablation. Left atrial (LA) fibrosis, LA volume, LA ejection fraction (EF), left ventricular ejection fraction (LVEF), LA shape (sphericity) and pulmonary vein anatomy have all been shown to correlate with late AF recurrence. This study aimed to validate and assess the relative contribution of multiple indices in a long-term single-center study. Eighty-nine patients (53% paroxysmal AF, 73% male) underwent comprehensive CMR study before first-time AF ablation (median follow-up 726 days [IQR: 418-1010 days]). The 3D late gadolinium-enhanced acquisition (1.5T, 1.3 × 1.3 × 2 mm) was quantified for fibrosis; LA volume and sphericity were assessed on manual segmentation at atrial diastole; LAEF and LVEF were quantified on multislice cine imaging. AF recurred in 43 patients (48%) overall (31 at 1 year). In the recurrence group, LA fibrosis was higher (42% vs 29%; hazard ratio [HR]: 1.032; P = .002), left atrial ejection fraction (LAEF) lower (25% vs 34%; HR: 0.063; P = .016) and LVEF lower (57% vs 63%; HR: 0.011; P = .008). LA volume (135 vs 124 mL) and sphericity (0.819 vs 0.822) were similar. Multivariate Cox regression analysis was adjusted for age and sex (Model 1), additionally AF type (Model 2) and combined (Model 3). In Models 1 and 2, LA fibrosis, LAEF, and LVEF were independently associated with outcome, but only LA fibrosis was independent in Model 3 (HR: 1.021; P = .022). LAEF, LVEF, and LA fibrosis differed significantly in the AF recurrence cohort. However, on combined multivariate analysis only LA fibrosis remained independently associated with outcome.

Chubb H ，Karim R ，Mukherjee R ，Williams SE ，Whitaker J ，Harrison J ，Niederer SA ，Staab W ，Gill J ，Schaeffter T ，Wright M ，O'Neill M ，Razavi R ... -  《-》

The association of baseline left atrial structure and function measured with cardiac magnetic resonance and pulmonary vein isolation outcome in patients with drug-refractory atrial fibrillation.

Prognostic significance of left atrial (LA) function in patients with atrial fibrillation (AF) is poorly defined. To examine the association of LA function measured with cardiac magnetic resonance (CMR) feature-tracking and AF recurrence following catheter ablation. One hundred and twenty-one AF patients (72% paroxysmal, mean age 59 ± 10 years) were enrolled. Baseline LA function was measured by calculating passive, active, and total emptying fractions (LAEF) and analysis of global longitudinal strain and strain rates. Patients were followed up for recurrence of AF or atrial tachycardia (AT). Hazard ratios for recurrence were calculated using Cox proportional models adjusted for potential clinical confounders, type of AF, left ventricular ejection fraction, AF duration, LA volume, and late gadolinium enhancement (LGE). During a mean follow-up of 18 ± 9 months, 52 patients (43%) experienced recurrent AF/AT. Patients with recurrent AF/AT had higher baseline LA volume index and lower LA passive, and total LAEF (P < .05 for all). The baseline peak LA strain and strain rates in all phases of LA function were lower in the AF/AT recurrence group (P < .01 for all). In multivariable analysis total LAEF, peak LA strain, and systolic and late diastolic strain rates were associated with recurrence. Both peak LA strain and total LAEF improved prediction of recurrent AT/AF compared to the baseline clinical model, including LA LGE (C statistic 0.82 vs 0.77, P < .05 for both total LAEF and peak LA strain). LA reservoir function was independently associated with recurrent AF/AT after PVI and can additionally improve risk stratification in patients undergoing PVI.

Habibi M ，Lima JAC ，Gucuk Ipek E ，Zimmerman SL ，Zipunnikov V ，Spragg D ，Ashikaga H ，Rickard J ，Marine JE ，Berger RD ，Calkins H ，Nazarian S ... -  《-》

Left atrial geometry and outcome of atrial fibrillation ablation: results from the multicentre LAGO-AF study.

Bisbal F ，Alarcón F ，Ferrero-de-Loma-Osorio A ，González-Ferrer JJ ，Alonso C ，Pachón M ，Tizón H ，Cabanas-Grandío P ，Sanchez M ，Benito E ，Teis A ，Ruiz-Granell R ，Pérez-Villacastín J ，Viñolas X ，Arias MA ，Vallés E ，García-Campo E ，Fernández-Lozano I ，Villuendas R ，Mont L ... -  《-》

Conventional versus 3-D Echocardiography to Predict Arrhythmia Recurrence After Atrial Fibrillation Ablation.

Arrhythmia recurrence after atrial fibrillation (AF) ablation remains high and requires repeat interventions in a substantial number of patients. We assessed the value of conventional and 3-D echocardiography to predict AF recurrence. Consecutive patients undergoing AF ablation by means of pulmonary vein isolation were included in a prospective registry. Echocardiograms were obtained prior to the ablation procedure, and analyzed offline in a standardized manner, including 3-D left atrial (LA) volumetry and determination of LA function and sphericity. The primary endpoint, AF recurrence (>30 seconds) between 3 to 12 months after AF ablation, was independently adjudicated. We included 276 patients (73% male, mean age 59.9 ± 9.9 years). Paroxysmal and persistent AF were present in 178 (64%) and 98 (36%) patients, respectively. Mean left ventricular ejection fraction and indexed LA volume in 3-D (LAVI) were 52 ± 12% and 42 ± 13 mL/m2 , respectively. AF recurrence was observed in 110 (40%) patients after a single procedure. Median (interquartile range) time to AF recurrence was 123 (92; 236) days. In multivariable Cox regression models, the only predictors for AF recurrence were the minimal, maximal, and indexed 3-D LA volumes, P = 0.024, P = 0.016, and P = 0.014, respectively. Quartile specific analysis of 3-D LAVI showed an HR of 1.885 (95%CI 1.066-3.334; P for trend = 0.015) for the highest compared to the lowest quartile. Our results show the important role of LA volume for the long-term freedom from arrhythmia after AF ablation. These data also highlight the potential of 3-D echocardiography in this context and may facilitate patient selection for AF ablation.

Bossard M ，Knecht S ，Aeschbacher S ，Buechel RR ，Hochgruber T ，Zimmermann AJ ，Kessel-Schaefer A ，Stephan FP ，Völlmin G ，Pradella M ，Sticherling C ，Osswald S ，Kaufmann BA ，Conen D ，Kühne M ... -  《-》

Relationship between atrial scar on cardiac magnetic resonance and pulmonary vein reconnection after catheter ablation for paroxysmal atrial fibrillation.

Pulmonary vein (PV) reconnection is frequent in patients showing atrial fibrillation (AF) recurrence after PV isolation (PVI). Its detection with cardiac magnetic resonance (CMR) may help predict outcome and guide redo procedures. We assessed the relationship between scar on CMR and PV reconnection after catheter ablation for paroxysmal AF. Fifty-one patients with paroxysmal AF underwent CMR before PVI using either a conventional single-electrode catheter (N = 28) or a circular multielectrode catheter (N = 23). At 3 months, a second CMR study was performed, followed by a systematic electrophysiological procedure to look for PV reconnection, regardless of AF recurrence. Preablation fibrosis and postablation scar were quantified and mapped from late gadolinium-enhanced CMR. CMR results were compared to the distribution and extent of PV reconnection. CMR and electrophysiological findings were compared between catheter types. Three months after successful PVI, scar gaps were found in 39 (76%) patients, and 78 (39%) veins. Electrical PV reconnection was detected in 45 (88%) patients, and 99 (50%) veins. The extent of PV reconnection related closely to the number of gaps (R = 0.55; P < .001), and to scar burden (R = -0.63; P < .001). However, the agreement was only fair for the localization of PV reconnection (k = 0.37; P < .001), scar gaps particularly lacking sensitivity in areas of pre-existing fibrosis. The circular catheter was associated with shorter procedures (P < .001), more scar (P = .01), less gaps (P = .01), and less reconnected veins (P = .03). PV reconnection is extremely frequent after PVI. CMR scar imaging accurately predicts its extent, but poorly predicts its location. Multielectrode circular catheters induce more complete ablation.

Jefairi NA ，Camaioni C ，Sridi S ，Cheniti G ，Takigawa M ，Nivet H ，Denis A ，Derval N ，Mathilde Merle ，Laurent F ，Montaudon M ，Sacher F ，Hocini M ，Haissaguerre M ，Jais P ，Cochet H ... -  《-》