Background: The Subcutaneous ICD (S-ICD) is safe and effective for sudden cardiac death prevention. However, patients in previous S-ICD studies had fewer comorbidities, less left ventricular dysfunction and received more inappropriate shocks (IAS) than in typical transvenous (TV)-ICD trials. The UNTOUCHED trial was designed to evaluate the IAS rate in a more typical, contemporary ICD patient population implanted with the S-ICD using standardized programming and enhanced discrimination algorithms. Methods: Primary prevention patients with left ventricular ejection fraction (LVEF) ≤ 35% and no pacing indications were included. Generation 2 or 3 S-ICD devices were implanted and programmed with rate-based therapy delivery for rates ≥ 250 beats per minute (bpm) and morphology discrimination for rates ≥200 and < 250 bpm. Patients were followed for 18 months. The primary endpoint was the IAS free rate compared to a 91.6% performance goal, derived from the results for the ICD-only patients in the MADIT-RIT study. Kaplan-Meier analyses were performed to evaluate event-free rates for IAS, all cause shock, and complications. Multivariable proportional hazard analysis was performed to determine predictors of endpoints. Results: S-ICD implant was attempted in 1116 patients and 1111 patients were included in post-implant follow-up analysis. The cohort had a mean age of 55.8±12.4 years, 25.6% women, 23.4% black race, 53.5% with ischemic heart disease, 87.7% with symptomatic heart failure and a mean LVEF of 26.4±5.8%. Eighteen-month freedom from IAS was 95.9% (Lower confidence limit LCL 94.8%). Predictors of reduced incidence of IAS were implanting the most recent generation of device, using the three-incision technique, no history of atrial fibrillation, and ischemic etiology. The 18-month all cause shock free rate was 90.6% (LCL 89.0%), meeting the prespecified performance goal of 85.8%. Conversion success rate for appropriate, discrete episodes was 98.4%. Complication free rate at 18 months was 92.7%. Conclusions: This study demonstrates high efficacy and safety with contemporary S-ICD devices and programming despite the relatively high incidence of co-morbidities in comparison to earlier S-ICD trials. The inappropriate shock rate (3.1% at one year) is the lowest reported for the S-ICD and lower than many TV ICD studies using contemporary programming to reduce IAS. Clinical Trial Registration: URL https://clinicaltrials.gov Unique Identifier NCT02433379

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Background-The Cox Maze procedure for treatment of medically refractory atrial fibrillation (AF) is limited by its complexity and requirement for cardiopulmonary bypass. Long-term follow-up and success using criteria established by the Heart Rhythm Society/European Heart Rhythm Association/European Cardiac Arrhythmia Society consensus statement have not been reported for surgical AF ablation. We describe the results of using a thorascopic approach and radiofrequency energy to perform bilateral pulmonary vein isolation and left atrial ganglionic plexi ablation for treatment of AF. Methods and Results-Forty-five (33 paroxysmal; 12 persistent) consecutive patients underwent thorascopic bilateral radiofrequency pulmonary vein isolation, ganglionic plexi ablation, ligament of Marshall ablation, and left atrial appendage exclusion by a single surgeon. Forty-three patients were prospectively followed without antiarrhythmic drugs for a minimum of 1 year with a 30-day continuous event monitor or pacemaker interrogation at 6 and 12 months. Failure was defined as any atrial tachyarrhythmia of Ͼ30 seconds' duration occurring Ͼ90 days after surgery. Mean follow-up was 516Ϯ181 days (202 to 858 days). Twenty-eight (65%) patients had no atrial tachyarrhythmia Ͼ30 seconds by 1 year, and 15 (35%) patients had atrial tachyarrhythmia recurrences by 1 year. Eight of 15 patients with recurrent AF had catheter ablation resulting in elimination and/or reduction of AF episodes in 7 of 8 patients. Four of 15 patients had AF elimination or reduction with antiarrhythmic drugs alone. Three patients did not benefit from surgery and received rate control only. There were no deaths; 1 phrenic nerve injury and 2 pleural effusions were the only major complications. Conclusions-The single procedure success at 1-year follow-up for surgical pulmonary vein isolation and ganglionic plexi ablation is 65%. Atrial tachyarrhythmia recurrences after surgery are usually responsive to catheter ablation and/or antiarrhythmic drugs.

The implantable-cardioverter defibrillator (ICD) lead is the most vulnerable component of the ICD system. Despite advanced engineering design, sophisticated manufacturing techniques, and extensive bench, pre-clinical, and clinical testing, lead failure (LF) remains the Achilles' heel of the ICD system. ICD LF has a broad range of adverse outcomes, ranging from intermittent inappropriate pacing to proarrhythmia leading to patient mortality. ICD LF is often considered in the context of design or construction defects, but is more appropriately considered in the context of the finite service life of a mechanical component placed in chemically stressful environment and subjected to continuous mechanical stresses. This clinical review summarizes LF mechanisms, assessment, and differential diagnosis of LF, including lead diagnostics, recent prominent lead recalls, and management of LF and functioning, but recalled leads. Despite recent advances in lead technology, physicians will likely continue to need to understand how to manage patients with transvenous ICD leads.