Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is a rare, inherited cardiomyopathy characterized by ventricular arrhythmias, sudden cardiac death, and right ventricular ...dysfunction. Since the first major description of this disease, much has been learned about ARVD/C. One of the main breakthroughs was the discovery that mutations in desmosomal proteins are the most frequent genetic basis of ARVD/C. Today, genetic testing plays an important role in both the diagnosis of ARVD/C and cascade family screening. Much has also been learned concerning the optimal approaches to diagnosis. The 2010 Task Force Diagnostic criteria for ARVD/C represent the standard for diagnosis today. We have also learned much about the importance of proband status and the 24-h PVC count to assess sudden death risk, and the importance of exercise both in the development of ARVD/C in susceptible individuals and in defining the course of the disease. From a treatment perspective, placement of ICDs in specific subsets of patients with ARVD/C who are at increased risk of sudden death is important. The techniques of VT ablation have also evolved over time and are valuable components of our management strategies for the ARVD/C patient today. This review will provide an update on ARVD/C, with specific attention to some of the contributions to this field reported by the Johns Hopkins ARVD/C Program. (Circ J 2015; 79: 901–913)
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiomyopathy characterized by ventricular arrhythmias and an increased risk of sudden cardiac death. Although structural ...abnormalities of the right ventricle predominate, it is well recognized that left ventricular involvement is common, particularly in advanced disease, and that left-dominant forms occur. The pathological characteristic of ARVC is myocyte loss with fibrofatty replacement. Since the first detailed clinical description of the disorder in 1982, significant advances have been made in understanding this disease. Once the diagnosis of ARVC is established, the single most important clinical decision is whether a particular patient's sudden cardiac death risk is sufficient to justify placement of an implantable cardioverter-defibrillator. The importance of this decision reflects the fact that ARVC is a common cause of sudden death in young people and that sudden death may be the first manifestation of the disease. This decision is particularly important because these are often young patients who are expected to live for many years. Although an implantable cardioverter-defibrillator can save lives in individuals with this disease, it is also well recognized that implantable cardioverter-defibrillator therapy is associated with both short- and long-term complications. Decisions about the placement of an implantable cardioverter-defibrillator are based on an estimate of a patient's risk of sudden cardiac death, as well as their preferences and values. The primary purpose of this article is to provide a review of the literature that concerns risk stratification in patients with ARVC and to place this literature in the framework of the 3 authors' considerable lifetime experiences in caring for patients with ARVC. The most important parameters to consider when determining arrhythmic risk include electric instability, including the frequency of premature ventricular contractions and sustained ventricular arrhythmia; proband status; extent of structural disease; cardiac syncope; male sex; the presence of multiple mutations or a mutation in TMEM43; and the patient's willingness to restrict exercise and to eliminate participation in competitive or endurance exercise.
Objectives This study sought to determine how exercise influences penetrance of arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) among patients with desmosomal mutations. Background ...Although animal models and anecdotal evidence suggest that exercise is a risk factor for ARVD/C, there have been no systematic human studies. Methods Eighty-seven carriers (46 male; mean age, 44 ± 18 years) were interviewed about regular physical activity from 10 years of age. The relationship of exercise with sustained ventricular arrhythmia (ventricular tachycardia/ventricular fibrillation VT/VF), stage C heart failure (HF), and meeting diagnostic criteria for ARVD/C (2010 Revised Task Force Criteria TFC) was studied. Results Symptoms developed in endurance athletes (N = 56) at a younger age (30.1 ± 13.0 years vs. 40.6 ± 21.1 years, p = 0.05); they were more likely to meet TFC at last follow-up (82% vs. 35%, p < 0.001) and have a lower lifetime survival free of VT/VF (p = 0.013) and HF (p = 0.004). Compared with those who did the least exercise per year (lowest quartile) before presentation, those in the second (odds ratio OR: 6.64, p = 0.013), third (OR: 16.7, p = 0.001), and top (OR: 25.3, p < 0.0001) quartiles were increasingly likely to meet TFC. Among 61 individuals who did not present with VT/VF, the 13 subjects experiencing a first VT/VF event over a mean follow-up of 8.4 ± 6.7 years were all endurance athletes (p = 0.002). Survival from a first VT/VF event was lowest among those who exercised most (top quartile) both before (p = 0.036) and after (p = 0.005) clinical presentation. Among individuals in the top quartile, a reduction in exercise decreased VT/VF risk (p = 0.04). Conclusions Endurance exercise and frequent exercise increase the risk of VT/VF, HF, and ARVD/C in desmosomal mutation carriers. These findings support exercise restriction for these patients.
Catheter ablation of atrial fibrillation (AF) is now an important therapeutic modality for patients with AF. There is considerable evidence available from several prospective randomized trials ...demonstrating that catheter ablation of AF is superior to antiarrhythmic drug therapy in controlling AF and that AF ablation improves quality of life substantially. This is especially true for patients with paroxysmal AF without other severe comorbidities. Catheter ablation is indicated for treatment of patients with symptomatic AF in whom one or more attempts at class 1 or 3 antiarrhythmic drug therapy have failed. Although current guidelines state that is appropriate to perform catheter ablation as a first-line therapy in selected patients, in our clinical practice this is rare. This reflects a number of important realities concerning the field of AF ablation. Catheter ablation of AF is a challenging and complex procedure, which is not free of the risk of potentially life-threatening complications, such as an atrio-oesophageal fistula, stroke, and cardiac tamponade. Although these major complications are rare and their rate is falling, they must be considered by both patients and physicians. The progress made and the new developments on the horizon in the field of AF catheter ablation are remarkable. When radiofrequency catheter ablation was first introduced in the late 1980s, few would have predicted that catheter ablation of AF would emerge as the most commonly performed ablation procedure in most major hospitals.
Catheter ablation of atrial fibrillation is typically performed with uninterrupted anticoagulation with warfarin or interrupted non-vitamin K antagonist oral anticoagulant therapy. Uninterrupted ...anticoagulation with a non-vitamin K antagonist oral anticoagulant, such as dabigatran, may be safer; however, controlled data are lacking. We investigated the safety of uninterrupted dabigatran versus warfarin in patients undergoing ablation of atrial fibrillation.
In this randomized, open-label, multicenter, controlled trial with blinded adjudicated end-point assessments, we randomly assigned patients scheduled for catheter ablation of paroxysmal or persistent atrial fibrillation to receive either dabigatran (150 mg twice daily) or warfarin (target international normalized ratio, 2.0 to 3.0). Ablation was performed after 4 to 8 weeks of uninterrupted anticoagulation, which was continued during and for 8 weeks after ablation. The primary end point was the incidence of major bleeding events during and up to 8 weeks after ablation; secondary end points included thromboembolic and other bleeding events.
The trial enrolled 704 patients across 104 sites; 635 patients underwent ablation. Baseline characteristics were balanced between treatment groups. The incidence of major bleeding events during and up to 8 weeks after ablation was lower with dabigatran than with warfarin (5 patients 1.6% vs. 22 patients 6.9%; absolute risk difference, -5.3 percentage points; 95% confidence interval, -8.4 to -2.2; P<0.001). Dabigatran was associated with fewer periprocedural pericardial tamponades and groin hematomas than warfarin. The two treatment groups had a similar incidence of minor bleeding events. One thromboembolic event occurred in the warfarin group.
In patients undergoing ablation for atrial fibrillation, anticoagulation with uninterrupted dabigatran was associated with fewer bleeding complications than uninterrupted warfarin. (Funded by Boehringer Ingelheim; RE-CIRCUIT ClinicalTrials.gov number, NCT02348723 .).
Pulsed field ablation uses electrical pulses to cause nonthermal irreversible electroporation and induce cardiac cell death. Pulsed field ablation may have effectiveness comparable to traditional ...catheter ablation while preventing thermally mediated complications.
The PULSED AF pivotal study (Pulsed Field Ablation to Irreversibly Electroporate Tissue and Treat AF) was a prospective, global, multicenter, nonrandomized, paired single-arm study in which patients with paroxysmal (n=150) or persistent (n=150) symptomatic atrial fibrillation (AF) refractory to class I or III antiarrhythmic drugs were treated with pulsed field ablation. All patients were monitored for 1 year using weekly and symptomatic transtelephonic monitoring; 3-, 6-, and 12-month ECGs; and 6- and 12-month 24-hour Holter monitoring. The primary effectiveness end point was freedom from a composite of acute procedural failure, arrhythmia recurrence, or antiarrhythmic escalation through 12 months, excluding a 3-month blanking period to allow recovery from the procedure. The primary safety end point was freedom from a composite of serious procedure- and device-related adverse events. Kaplan-Meier methods were used to evaluate the primary end points.
Pulsed field ablation was shown to be effective at 1 year in 66.2% (95% CI, 57.9 to 73.2) of patients with paroxysmal AF and 55.1% (95% CI, 46.7 to 62.7) of patients with persistent AF. The primary safety end point occurred in 1 patient (0.7%; 95% CI, 0.1 to 4.6) in both the paroxysmal and persistent AF cohorts.
PULSED AF demonstrated a low rate of primary safety adverse events (0.7%) and provided effectiveness consistent with established ablation technologies using a novel irreversible electroporation energy to treat patients with AF.
URL: https://www.
gov; Unique identifier: NCT04198701.
Abstract
Arrhythmogenic cardiomyopathy (ACM) is a heritable cardiomyopathy characterized by frequent ventricular arrhythmias and progressive ventricular dysfunction. Risk of sudden cardiac death is ...elevated in ACM patients and can be the presenting symptom particularly in younger individuals and athletes. This review describes current understanding of the genetic architecture of ACM and molecular mechanisms of ACM pathogenesis. We consider an emerging threshold model for ACM inheritance in which multiple factors including pathogenic variants in known ACM genes, genetic modifiers, and environmental exposures, particularly exercise, are required to reach a threshold for disease expression. We also review best practices for integrating genetics—including recent discoveries—in caring for ACM families and emphasize the utility of genotype for both management of affected individuals and predictive testing in family members.
Objectives The purpose of this study was to provide a systematic multicenter survey on the incidence and causes of death occurring in the setting of or as a consequence of catheter ablation (CA) of ...atrial fibrillation (AF). Background CA of AF is considered to be generally safe. However, serious complications, including death, have been reported. Methods Using a retrospective case series, data relevant to the incidence and cause of intra- and post-procedural death occurring in patients undergoing CA of AF between 1995 and 2006 were collected from 162 of 546 identified centers worldwide. Results Thirty-two deaths (0.98 per 1,000 patients) were reported during 45,115 procedures in 32,569 patients. Causes of deaths included tamponade in 8 patients (1 later than 30 days), stroke in 5 patients (2 later than 30 days), atrioesophageal fistula in 5 patients, and massive pneumonia in 2 patients. Myocardial infarction, intractable torsades de pointes, septicemia, sudden respiratory arrest, extrapericardial pulmonary vein (PV) perforation, occlusion of both lateral PVs, hemothorax, and anaphylaxis were reported to be responsible for 1 death each, while asphyxia from tracheal compression secondary to subclavian hematoma, intracranial bleeding, acute respiratory distress syndrome, and esophageal perforation from an intraoperative transesophageal echocardiographic probe were causes of 1 late death each. Conclusions Death is a complication of CA of AF, occurring in 1 of 1,000 patients. Knowledge of possible precipitating causes is key to operators and needs to be considered during decision making with patients.
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