Multicentre experience with the second-generation subcutaneous implantable cardioverter defibrillator and the intermuscular two-incision implantation technique.

INTRODUCTION: The recently developed second-generation subcutaneous implantable cardioverter defibrillator (S-ICD) and the intermuscular two-incision implantation technique demonstrate potential favorable features that reduce inappropriate shocks and complications. However, data concerning large patient populations are lacking. The aim of this multicentre prospective study was to evaluate the safety and outcome of second-generation S-ICD using the intermuscular two-incision technique in a large population study. METHODS AND RESULTS: The study population included 101 consecutive patients (75% male; mean age, 45 ± 13 years) who received second-generation S-ICD (EMBLEM; Boston Scientific, Marlborough, MA) implantation using the intermuscular two-incision technique as an alternative to the standard implantation technique. Twenty nine (29%) patients were implanted for secondary prevention. Twenty four (24%) patients had a previously implanted transvenous ICD. All patients were implanted without any procedure-related complications. Defibrillation testing was performed in 80 (79%) patients, and ventricular tachycardia was successfully converted at less than or equal to 65 J in 98.75% (79/80) of patients without pulse generator adjustments. During a median follow-up of 21 ± 10 months, no complications requiring surgical revision or local or systemic device-related infections were observed. Ten patients (9.9%) received appropriate and successful shocks for ventricular arrhythmias. Three (2.9%) patients experienced inappropriate shocks due to oversensing the cardiac signal (n = 1), noncardiac signal (n = 1), and a combination of both cardiac and noncardiac signals (n = 1), with one patient requiring device explantation. No patients required device explantation due to antitachycardia pacing indications. CONCLUSIONS: According to our multicentre study, second-generation S-ICD implanted with the intermuscular two-incision technique is an available safe combination and appears to be associated with a low risk of complications, such as inappropriate shocks.

Ultrasound-guided serratus anterior plane block for subcutaneous implantable cardioverter defibrillator implantation using the intermuscular two-incision technique.

PURPOSE: Operative anaesthetic requirements and perioperative discomfort are barriers to wide adoption of the subcutaneous implantable cardioverter defibrillator (S-ICD) system, especially when the intermuscular technique is used because of the greater amount of tissue dissection. The procedure is most commonly performed under general anaesthesia (GA). There is growing interest in transitioning away from the routine use of GA and towards several alternative anaesthesia modalities for the S-ICD implant procedure without the involvement of an anaesthesiologist. We assessed the feasibility of ultrasound-guided serratus anterior plane block (US-SAPB) in patients undergoing S-ICD implantation with the intermuscular two-incision technique. METHODS: The study population included 38 consecutive patients (84% male; median, 53 [46-62] years) who received S-ICD implantation using the intermuscular two-incision technique. All procedures were performed under US-SAPB and conscious sedation without the involvement of an anaesthesiologist. RESULTS: The average procedure time was 67 ± 14 min. No patient experienced significant haemodynamic changes or oxygen desaturation during the period of the US-SAPB procedure and sedation; there was no need for pharmacological interventions. The entire procedure was well tolerated without discomfort or complications and with no need for GA, except in one (2.6%) patient who received GA with a laryngeal mask airway. Patients always remained able to respond appropriately to neurological monitoring during the S-ICD implantation procedure. There were no procedure-related complications. CONCLUSIONS: US-SAPB and the intermuscular two-incision technique may be a promising safe and feasible combination for S-ICD implantation, overcoming the potential barrier to wider S-ICD adoption in clinical practice.

Subcutaneous implantable cardioverter defibrillator in patients with arrhythmogenic right ventricular cardiomyopathy: Results from an Italian multicenter registry.

BACKGROUND: Despite expanding indication of the subcutaneous implantable cardioverter defibrillator (S-ICD) in clinical practice, limited data exists on safety and efficacy of S-ICD in arrhythmogenic right ventricular cardiomyopathy (ARVC) patients. The aim of this multicenter study was to evaluate the safety and efficacy of S-ICD in ARVC patients. METHODS: The study population included 44 consecutive patients with definite ARVC diagnosis according to the 2010 ITF criteria (57% male, mean age 37 ±â€¯17 years [range 10-75 years]) who received an S-ICD. Eighteen (41%) patients were implanted for secondary prevention. RESULTS: At implant, all inducible patients (34/44) had conversion of ventricular fibrillation at 65 J. No early complications occurred. During a median follow-up of 12 months (7-19), 3 (6.8%) patients experienced complications requiring surgical revision. No local or systemic device-related infections were observed. Six patients (14%) received a total of 61 appropriate and successful shocks on ventricular arrhythmias. Six (14%) patients experienced 8 inappropriate shocks for oversensing of cardiac signal (4 cases) and non-cardiac signal (4 cases) with one patient requiring device explantation. No patients had the device explanted due to the need for antitachycardia pacing. CONCLUSIONS: The study shows that S-ICD provides safe and effective therapy for termination of both induced and spontaneous malignant ventricular tachyarrhythmias with high energy shocks in ARVC patients, but the risk of inappropriate shocks and complications needing surgical revision should be considered.

Subcutaneous Implantable Cardioverter-Defibrillator in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia: A Transatlantic Experience.

Background Despite growing use of the subcutaneous implantable cardioverter-defibrillator (S- ICD ), its clinical role in arrhythmogenic right ventricular cardiomyopathy/dysplasia ( ARVC /D) patients remains undefined. We aim to elucidate the cardiac phenotype, implant characteristics, and long-term efficacy regarding appropriate therapy and complications in ARVC /D patients with an S- ICD implant. Methods and Results A transatlantic cohort of ARVC /D patients who underwent S- ICD implantation was analyzed for clinical characteristics, S- ICD therapy, and long-term outcome including device-related complications. The cohort included 29 patients (52% male, 76% probands, 59% with ARVC /D-associated mutation, 59% primary prevention [no prior sustained ventricular arrhythmias], and 45% first-generation S- ICD devices). At implant, all inducible patients (27/29) had conversion of induced ventricular fibrillation. Two patients (7%) had superficial infections of the incision site that were treated conservatively. Over a median follow-up of 3.16 years (interquartile range: 2.21-4.51 years), all episodes (6 patients, 4% per year) of sustained ventricular arrhythmias were appropriately detected and treated. Six patients (21%) experienced 39 inappropriate shocks, with 3 requiring device explantation. Oversensing of noncardiac signal (n=4; especially myopotentials) and cardiac signal (n=4) was the most frequent etiology. No lead or device dislodgement, infection, skin erosion, or explantation related to need for antitachycardia pacing was noted. Conclusions S- ICD can effectively treat both induced and spontaneous ventricular arrhythmias in patients with ARVC /D. The rate of inappropriate shocks, although considerable, is comparable to that in ARVC /D patients treated with transvenous ICD s. When they occurred, inappropriate shocks were primarily due to cardiac and, uniquely, noncardiac oversensing. We suggest potential strategies for minimizing inappropriate therapy.

Implantable cardioverter defibrillator therapy in young patients with cardiomyopathies and channelopathies: a single Italian centre experience.

AIMS: This study was designed to prospectively evaluate the risk-benefit ratio of implantable cardioverter defibrillator (ICD) therapy in young patients with cardiomyopathies and channelopathies. METHODS AND RESULTS: The study population included 96 consecutive patients [68 men, median age 27 (22-32) years] with cardiomyopathies, such as arrhythmogenic right ventricular cardiomyopathy (n = 35), dilated cardiomyopathy (n = 17), hypertrophic cardiomyopathy (n = 15), Brugada syndrome (n = 14), idiopathic ventricular fibrillation (n = 5), left ventricular noncompaction (n = 4), long-QT syndrome (n = 4) and short-QT syndrome (n = 2), who were 18-35 years old at the time of ICD implantation. During a mean follow-up of 72.6 ±â€Š53.3 months, one patient with end-stage hypertrophic cardiomyopathy died because of acute heart failure, and 11 patients underwent orthotopic heart transplantation. Twenty patients (20.8%) had a total of 38 appropriate ICD interventions (4%/year), and 26 patients (27.1%) experienced a total of 49 adverse ICD-related events (5.4%/year), including 23 inappropriate ICD interventions occurring in nine patients (9.4%) and 26 device-related complications requiring surgical revision occurring in 20 patients (20.8%). Lead failure/fracture requiring lead extraction was the most common complication (n = 9). A threshold for ICD therapy less than 300 ms was associated with a borderline significant lower probability of inappropriate ICD interventions (hazard ratio = 0.2; 95% confidence interval 0.02-1.2; P = 0.07), whereas underweight status was an independent predictor of device-related complications (hazard ratio = 5.4; 95% confidence interval 1.5-19.4; P = 0.01). CONCLUSION: In young patients with cardiomyopathies and channelopathies, ICD therapy provided life-saving protection by effectively terminating life-threatening ventricular arrhythmias. However, because ICD-related adverse events are common, the risk/benefit ratio should be carefully assessed when considering ICD implantation in young people.