Drug-Refractory Ventricular Tachycardias Following Myocarditis: Endocardial and Epicardial Radiofrequency Catheter Ablation

BACKGROUND: -Ventricular tachycardia (VT) is a significant therapeutic challenge in patients with myocarditis. This study aimed to assess the efficacy and safety of radiofrequency catheter ablation (RFCA) of VT in pts with myocarditis. METHODS AND RESULTS: -We enrolled 20 patients (15 males, age 42 [28-52] years) with a history of biopsy-proven viral myocarditis and drug-refractory VT; 5 patients presented with electrical storm. The median left ventricular ejection fraction was 55 (45-60)%. All patients underwent endocardial RFCA with an irrigated catheter, using contact electroanatomical mapping. Recurrence of sustained VT after endocardial RFCA was treated with additional epicardial RFCA. Endocardial RFCA was acutely successful in 14 patients (70%), while in the remaining 6 (30%) clinical VT was successfully ablated by epicardial RFCA. In one patient, hemodynamic instability required an intraaortic balloon pump to complete RFCA. No major complication occurred during or after RFCAs. Over a median follow-up time of 28 (11-48) months, 18 patients (90%) remained free of sustained VT; two patients (10%, both with baseline LVEF 64 35%) died of acute heart failure unrelated to ventricular arrhythmias. CONCLUSIONS: -In patients with myocarditis, RFCA of drug-refractory VT is feasible, safe and effective. Epicardial RFCA should be considered as an important therapeutic option to increase success rate

Near zero fluoroscopic exposure during catheter ablation of supraventricular arrhythmias:the no-party multicentre randomized trial

Abstract Aims: Aim of this study was to compare a minimally fluoroscopic radiofrequency catheter ablation with conventional fluoroscopy-guided ablation for supraventricular tachycardias (SVTs) in terms of ionizing radiation exposure for patient and operator and to estimate patients’ lifetime attributable risks associated with such exposure. Methods and results: We performed a prospective, multicentre, randomized controlled trial in six electrophysiology (EP) laboratories in Italy. A total of 262 patients undergoing EP studies for SVT were randomized to perform a minimally fluoroscopic approach (MFA) procedure with the EnSiteTMNavXTM navigation system or a conventional approach (ConvA) procedure. The MFA was associated with a significant reduction in patients’ radiation dose (0 mSv, iqr 0–0.08 vs. 8.87 mSv, iqr 3.67–22.01; P < 0.00001), total fluoroscopy time (0 s, iqr 0–12 vs. 859 s, iqr 545–1346; P < 0.00001), and operator radiation dose (1.55 vs. 25.33 µS per procedure; P < 0.001). In the MFA group, X-ray was not used at all in 72% (96/134) of cases. The acute success and complication rates were not different between the two groups (P = ns). The reduction in patients’ exposure shows a 96% reduction in the estimated risks of cancer incidence and mortality and an important reduction in estimated years of life lost and years of life affected. Based on economic considerations, the benefits of MFA for patients and professionals are likely to justify its additional costs. Conclusion: This is the first multicentre randomized trial showing that a MFA in the ablation of SVTs dramatically reduces patients’ exposure, risks of cancer incidence and mortality, and years of life affected and lost, keeping safety and efficacy. Trial registration: clinicaltrials.gov Identifier: NCT01132274