Electrophysiological findings and long-term outcomes of percutaneous ablation of atrial arrhythmias after surgical ablation for atrial fibrillation

OBJECTIVES: Percutaneous ablation (PA) for relapsing atrial tachyarrhythmias after surgical ablation is an emerging therapy. The aim of this study is to report the electrophysiological findings and the procedural long-term outcomes of reablation, in this particular clinical setting. METHODS: We retrospectively analysed all patients who were readmitted to our centre for relapsing atrial arrhythmias after surgical ablation for atrial fibrillation (AF). RESULTS: From 2000 to 2011, 36 patients with previous surgical ablation of AF received additional percutaneous management. Seven patients had had biatrial Maze, 18 left atrial ablation lesion set and 11 pulmonary vein isolation. Energy sources involved were unipolar radiofrequency (RF) (n = 13), bipolar RF (n = 19), combined bipolar RF and cryoenergy (n = 2), cryoenergy (n = 1) and high intensity focused ultrasound (n = 1). The median time to reablation was 34 months (interquartile range: 10-66). The relapsing arrhythmias were left atrial tachycardia (n = 17), AF (n = 15), right atrial flutter (n = 2), right atrial tachycardia (n = 1) and biatrial atrial tachycardia (n = 1). Origin of re-entrant circuits was perimitral (n = 27), around pulmonary veins (PV) including posterior left atrium (n = 15) and cavotricuspid isthmus (n = 3). Twenty-seven (75%) patients had left isthmus catheter ablation and 11 (30%) reablation of PV. Eighteen out of the 27 perimitral circuits were in patients with previous left-atrial Maze; in 17 patients the mitral line was performed with bipolar RF only, without the addition of cryoenergy. The importance of an appropriate energy source is also underlined by the prevalence of gaps in PV isolation that occurred for two-thirds of patients treated using unipolar RF only, which has been discontinued since 2001. Ten patients (27%) needed more than 1 PA for relapsing arrhythmia. At the last follow-up of 97 ± 42 months, freedom from arrhythmias was 53% after single PAs and 67% after more than one procedure. No morbidity, mortality or strokes were recorded during the follow-up. CONCLUSIONS: Percutaneous treatment of highly symptomatic patients with unsuccessful previous surgical ablation is feasible, and relatively effective at the late follow-up. A multidisciplinary approach significantly improves the outcomes in these challenging patients

Patients with Cardiac Implantable Electronic Device Undergoing Radiation Therapy: Insights from a Ten-Year Tertiary Center Experience

Background: The number of patients with cardiac implantable electronic devices (CIEDs) receiving radiotherapy (RT) is increasing. The management of CIED-carriers undergoing RT is challenging and requires a collaborative multidisciplinary approach. Aim: The aim of the study is to report the real-world, ten-year experience of a tertiary multidisciplinary teaching hospital. Methods: We conducted an observational, real-world, retrospective, single-center study, enrolling all CIED-carriers who underwent RT at the San Raffaele University Hospital, between June 2010 and December 2021. All devices were MRI-conditional. The devices were programmed to an asynchronous pacing mode for patients who had an intrinsic heart rate of less than 40 beats per minute. An inhibited pacing mode was used for all other patients. All tachyarrhythmia device functions were temporarily disabled. After each RT session, the CIED were reprogrammed to the original settings. Outcomes included adverse events and changes in the variables that indicate lead and device functions. Results: Between June 2010 and December 2021, 107 patients were enrolled, among which 63 (58.9%) were pacemaker carriers and 44 (41.1%) were ICD carriers. Patients were subjected to a mean of 16.4 (±10.7) RT sessions. The most represented tumors in our cohort were prostate cancer (12; 11%), breast cancer (10; 9%) and lung cancer (28; 26%). No statistically significant changes in device parameters were recorded before and after radiotherapy. Generator failures, power-on resets, changes in pacing threshold or sensing requiring system revision or programming changes, battery depletions, pacing inhibitions and inappropriate therapies did not occur in our cohort of patients during a ten-year time span period. Atrial arrhythmias were recorded during RT session in 14 patients (13.1%) and ventricular arrhythmias were observed at device interrogation in 10 patients (9.9%). Conclusions: Changes in device parameters and arrhythmia occurrence were infrequent, and none resulted in a clinically significant adverse event

Long-Term Follow-Up of Catheter Ablation for Premature Ventricular Complexes in the Modern Era: The Importance of Localization and Substrate

Background: Large-scale studies evaluating long-term recurrence rates in both idiopathic and non-idiopathic PVC catheter ablation (CA) patients have not been reported. Objective: To evaluate the efficacy and safety of idiopathic and non-idiopathic PVC CA, investigating the predictors of acute and long-term efficacy. Methods: This retrospective multicentric study included 439 patients who underwent PVC CA at three institutions from April-2015 to December-2021. Clinical success at 6 months’ follow-up, defined as a reduction of at least 80% of the pre-procedural PVC burden, was deemed the primary outcome. The secondary aims of the study were: clinical success at the last available follow-up, predictors of arrhythmic recurrences at long-term follow-up, and safety outcomes. Results: The median age was 51 years, with 24.9% patients being affected suffering from structural heart disease. The median pre-procedural PVC burden was 20.1%. PVCs originating from the RVOT were the most common index PVC observed (29.1%), followed by coronary cusp (CC) and non-outflow tract (OT) LV PVCs (23.1% and 19.0%). The primary outcome at 6 months was reached in 85.1% cases, with a significant reduction in the 24 h% PVC burden (−91.4% [−83.4; −96.7], p < 0.001); long-term efficacy was observed in 82.1% of cases at almost 3-year follow-up. The presence of underlying structural heart disease and non-OT LV region origin (aHR 1.77 [1.07–2.93], p = 0.027 and aHR = 1.96 [1.22–3.14], p = 0.005) was independently associated with recurrences. Conclusion: CA of both idiopathic and non-idiopathic PVCs showed a very good acute and long-term procedural success rate, with an overall low complication. Predictors of arrhythmic recurrence at follow-up were underlying structural heart disease and non-OT LV origin

Inflammation as a Predictor of Recurrent\ua0Ventricular Tachycardia After Ablation in Patients With Myocarditis

Little is known about the risk stratification of patients with myocarditis undergoing ventricular tachycardia (VT) ablation