Background - Atrial fibrillation (AF) recurrence following catheter ablation remains high. Recent studies have shown a relation between epicardial adipose tissue (EAT) and AF. EAT secretes several pro- and anti-inflammatory adipokines that directly interact with the adjacent myocardium. The aim of the current study was to evaluate whether posterior left atrial (LA) adipose tissue attenuation, as marker of inflammation, is related to AF recurrences after catheter ablation. Methods - Consecutive patients with symptomatic AF referred for first AF catheter ablation who underwent CT were included. The total EAT and posterior LA adipose tissue were manually traced and adipose tissue was automatically recognized as tissue with Hounsfield units (HU) between -195 and -45. The attenuation value of the posterior LA adipose tissue was assessed and the population divided according to the mean HU value (-96.4 HU). Results - In total, 460 patients (66% male, age 61 ± 10 years) were included in the analysis. After a median follow-up of 18 months (IQR 6-32), 168 (37%) patients had AF recurrence. Patients with higher attenuation (≥-96.4 HU) of the posterior LA adipose tissue showed higher AF recurrence rates compared to patients with lower attenuation (<-96.4 HU) (log-rank test p=0.046). Univariate analysis showed an association between AF recurrence and higher posterior LA adipose tissue attenuation (≥-96.4 HU) (p<0.05). On multivariable analysis posterior LA adipose tissue attenuation (HR 1.26; 95% CI 0.90-1.76; p=0.181) remained a promising predictor of AF recurrence following catheter ablation. Conclusions - Posterior LA adipose tissue attenuation is a promising predictor of AF recurrence in patients who undergo catheter ablation. Higher adipose tissue attenuation might signal increased local inflammation and serve as an imaging biomarker of increased risk of AF recurrence.

IntroductionThe role of the spatial relationship between the left superior pulmonary vein (LSPV) and left atrial appendage (LAA) is unknown. We sought to evaluate whether an abutting LAA and LSPV play a role in AF recurrence after catheter ablation for paroxysmal AF.MethodsConsecutive patients, who underwent initial point-by-point radiofrequency catheter ablation for paroxysmal AF at the Heart and Vascular Center of Semmelweis University, Budapest, Hungary, between January of 2014 and December of 2017, were enrolled in the study. All patients underwent pre-procedural cardiac CT to assess left atrial (LA) and pulmonary vein (PV) anatomy. Abutting LAA-LSPV was defined as cases when the minimum distance between the LSPV and LAA was less than 2 mm.ResultsWe included 428 patients (60.7 ± 10.8 years, 35.5% female) in the analysis. AF recurrence rate was 33.4%, with a median recurrence-free time of 21.2 (8.8–43.0) months. In the univariable analysis, female sex (HR = 1.45; 95%CI = 1.04–2.01; p = 0.028), LAA flow velocity (HR = 1.01; 95%CI = 1.00–1.02; p = 0.022), LAA orifice area (HR = 1.00; 95%CI = 1.00–1.00; p = 0.028) and abutting LAA-LSPV (HR = 1.53; 95%CI = 1.09–2.14; p = 0.013) were associated with AF recurrence. In the multivariable analysis, abutting LAA-LSPV (adjusted HR = 1.55; 95%CI = 1.04–2.31; p = 0.030) was the only independent predictor of AF recurrence.ConclusionAbutting LAA-LSPV predisposes patients to have a higher chance for arrhythmia recurrence after catheter ablation for paroxysmal AF.

Introduction There are no consistently confirmed predictors of atrial fibrillation (AF) recurrence after catheter ablation. Therefore, we aimed to study whether left atrial appendage volume (LAAV) and function influence the long‐term recurrence of AF after catheter ablation, depending on AF type. Methods AF patients who underwent point‐by‐point radiofrequency catheter ablation after cardiac computed tomography (CT) were included in this analysis. LAAV and LAA orifice area were measured by CT. Uni‐ and multivariable Cox proportional hazard regression models were performed to determine the predictors of AF recurrence. Results In total, 561 AF patients (61.9 ± 10.2 years, 34.9% females) were included in the study. Recurrence of AF was detected in 40.8% of the cases (34.6% in patients with paroxysmal and 53.5% in those with persistent AF) with a median recurrence‐free time of 22.7 (9.3–43.1) months. Patients with persistent AF had significantly higher body surface area‐indexed LAV, LAAV, and LAA orifice area and lower LAA flow velocity, than those with paroxysmal AF. After adjustment left ventricular ejection fraction (LVEF) <50% (HR = 2.17; 95% CI = 1.38–3.43; p < .001) and LAAV (HR = 1.06; 95% CI = 1.01–1.12; p = .029) were independently associated with AF recurrence in persistent AF, while no independent predictors could be identified in paroxysmal AF. Conclusion The current study demonstrates that beyond left ventricular systolic dysfunction, LAA enlargement is associated with higher rate of AF recurrence after catheter ablation in persistent AF, but not in patients with paroxysmal AF.

Objective To assess whether anthropometrics, clinical risk factors, and coronary artery calcium score (CACS) can predict the need of further testing after coronary CT angiography (CTA) due to non-diagnostic image quality and/or the presence of significant stenosis. Methods Consecutive patients who underwent coronary CTA due to suspected coronary artery disease (CAD) were included in our retrospective analysis. We used multivariate logistic regression and receiver operating characteristics analysis containing anthropometric factors: body mass index, heart rate, and rhythm irregularity (model 1); and parameters used for pre-test likelihood estimation: age, sex, and type of angina (model 2); and also added total calcium score (model 3) to predict downstream testing. Results We analyzed 4120 (45.7% female, 57.9 ± 12.1 years) patients. Model 3 significantly outperformed models 1 and 2 (area under the curve, 0.84 [95% CI 0.83–0.86] vs. 0.56 [95% CI 0.54–0.58] and 0.72 [95% CI 0.70–0.74], p < 0.001). For patients with sinus rhythm of 50 bpm, in case of non-specific angina, CACS above 435, 756, and 944; in atypical angina CACS above 381, 702, and 890; and in typical angina CACS above 316, 636, and 824 correspond to 50%, 80%, and 90% probability of further testing, respectively. However, higher heart rates and arrhythmias significantly decrease these cutoffs (p < 0.001). Conclusion CACS significantly increases the ability to identify patients in whom deferral from coronary CTA may be advised as CTA does not lead to a final decision regarding CAD management. Our results provide individualized cutoff values for given probabilities of the need of additional testing, which may facilitate personalized decision-making to perform or defer coronary CTA. Key Points • Anthropometric parameters on their own are insufficient predictors of downstream testing. Adding parameters of the Diamond and Forrester pre-test likelihood test significantly increases the power of prediction. • Total CACS is the most important independent predictor to identify patients in whom coronary CTA may not be recommended as CTA does not lead to a final decision regarding CAD management. • We determined specific CACS cutoff values based on the probability of downstream testing by angina-, arrhythmia-, and heart rate–based groups of patients to help individualize patient management.

Background - The left atrial appendage (LAA) has been regarded as an important source of cardiac thrombus formation and appears important in the contribution to thrombo-embolism in patients with atrial fibrillation (AF). Our aim was to evaluate the relationship between LAA morphology and previous stroke and/or transient ischemic attack (TIA) in two large and distinct patient cohorts with and without known AF. Methods - The study population consisted of patients with and without drug-refractory AF who underwent computed tomography (CT) prior to transcatheter AF ablation, or clinically indicated for suspected coronary artery disease (CAD). The CT data were used for volumetric assessment of the left atrium (LA) and LAA and to determine LAA morphology. The LAA was classified by 3 readers in consensus as chicken wing, swan, cauliflower or windsock, based on predefined morphology classification criteria. Results - In total, 1813 patients (mean age 59 ± 11 years, 42% female) who underwent CT were included in this analysis (908 patients with AF and 905 patients without known AF). Swan LAA morphology was independently associated with prior stroke/TIA in the overall study population (OR 3.40, P <0.001), and in patients with (OR 2.88, P = 0.012) and without known AF (OR 3.96, P = 0.011). Conclusions - Swan morphology of the LAA is independently associated with prior stroke and/or TIA in patients with known AF, as well as in patients not previously diagnosed with AF.