Background-Reduced electrogram amplitude has been shown to correlate with diseased myocardium. We describe a novel individualized approach for catheter ablation of atrial fibrillation (AF) based on low-voltage areas (LVAs) in the left atrium (LA). We sought to assess (1) the incidence of LVAs in patients undergoing AF catheter ablation, (2) the distribution of LVAs within the LA, and (3) the effect of an individualized ablation strategy on long-term rhythm outcomes. Methods and Results-In 178 patients with paroxysmal or persistent AF, LA voltage maps were created during sinus rhythm after circumferential pulmonary vein isolation. Subsequent substrate modification was confined to the presence of LVA (<0.5 mV) and inducible regular atrial tachycardias. LVAs were identified in 35% and 10% of patients with persistent and paroxysmal AF, respectively. The LA roof and the anterior, septal, and posterior wall LA were most often affected. The 12-month atrial tachycardias/AF-free survival was 62% for patients without LVAs and 70% for patients with LVAs and tailored substrate modification (P=0.3). Success rate in a comparison group of 26 LVA patients without further substrate modification was 27%. Conclusions-LVAs can be found at preferred sites in 10% of patients with paroxysmal AF and in 35% of patients with persistent AF. This is the first clinical report describing a consistent voltage-based approach for substrate modification in addition to circumferential pulmonary vein isolation irrespective of AF type. Application of this limited individualized approach may have the potential to compensate for the impaired 12-month outcome of patients with endocardial structural defects. (Circ Arrhythm Electrophysiol. 2014;7:825-833.)

Catheter ablation of frequent PVCs is a low-risk and often effective treatment strategy to eliminate PVCs and associated symptoms. In patients with PVC-induced cardiomyopathy, cardiac function is frequently restored after successful ablation.

AF ablation still has a considerable number of major complications that may be life threatening or may lead to severe residues. Atrial-esophageal fistula is still observed despite continuous systematic methods to prevent it. Stroke, tamponade, and vascular complications are the most frequent major complications. However, in most patients treatment can be conservative and results in complete recovery. Advanced age and congestive heart failure seem to be associated with an increased risk of complications.

Background-Data on the outcomes of ventricular tachycardia (VT) ablation in nonischemic dilated cardiomyopathy (NIDCM) are insufficient. The Heart Center of Leipzig VT (HELP-VT) study was conducted prospectively to compare outcomes after radiofrequency catheter ablation of VT in patients with NIDCM compared with ischemic cardiomyopathy (ICM). Methods and Results-Two hundred twenty-seven patients, 63 with NIDCM and 164 with ICM, presenting with sustained VT were ablated with radiofrequency catheter ablation. Noninducibility of any clinical and nonclinical VT was achieved in 66.7% of NIDCM and in 77.4% of ICM patients. Ablation of the clinical VT only was achieved in 18.3% of ICM and in 22.2% of NIDCM patients. There was no statistically significant difference in short-term outcomes between the 2 groups. At the 1-year follow-up, VT-free survival in NIDCM was 40.5% compared with 57% in ICM. In univariate analysis, the hazard ratio for VT recurrence was significantly higher for NIDCM (1.62; 95% confidence interval, 1.12-2.34; P=0.01). In both the ICM and NIDCM subgroups, procedure failure and incomplete procedural success were independent predictors of VT recurrence. Conclusions-Although the short-term success rates after VT ablation in NIDCM and ICM patients were similar, the longterm outcomes in NIDCM patients were significantly worse. Complete VT noninducibility at the end of the ablation is associated with beneficial long-term outcome in NIDCM. Pursuing compete elimination of all inducible VTs is desirable and may improve the long-term success in NIDCM. (Circulation. 2014;129:728-736.)

Background Recurrent atrial fibrillation (AF) occurs in up to 50 % of patients within 1 year after catheter ablation, and a clinical risk score to predict recurrence remains a critical unmet need. The aim of this study was to (1) develop a simple score for the prediction of rhythm outcome following catheter ablation; (2) compare it with the CHADS2 and CHA2DS2-VASc scores, and (3) validate it in an external cohort. Methods Rhythm outcome between 3 and 12 months after AF catheter ablation were documented. The APPLE score [one point for age>65 years, persistent AF, impaired eGFR (<60 ml/min/1.73 m2), LA diameter ≥43 mm, EF < 50 %] was associated with AF recurrence and was validated in an external cohort in 261 patients with comparable ablation and follow-up. Results In 1145 patients (60 ± 10 years, 65 % male, 62 % paroxysmal AF) the APPLE score showed better prediction of AF recurrences (AUC 0.634, 95 % CI 0.600–0.668, p < 0.001) than CHADS2 (AUC 0.538) and CHA2DS2-VASc (AUC 0.542). Compared to patients with an APPLE score of 0, the odds ratio for AF recurrences was 1.73, 2.79 and 4.70 for APPLE scores 1, 2, or ≥3, respectively (all p < 0.05). In the external validation cohort, the APPLE score showed similar results (AUC 0.624, 95 % CI 0.562–0.687, p < 0.001). Conclusions The novel APPLE score is superior to the CHADS2 and CHA2DS2-VASc scores for prediction of rhythm outcome after catheter ablation. It holds promise as a useful tool to identify patients with low, intermediate, and high risk for AF recurrence.

In this single-centre study, individually tailored substrate modification guided by voltage mapping was associated with a significantly higher arrhythmia-free survival rate compared with a conventional approach applying linear ablation according to AF type.

Localized esophageal ulcer-like lesion is a frequent event after left atrial catheter ablation and can be found in patients whose intraluminal temperature has reached at least 41 degrees C.

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