Management of patients with Arrhythmogenic Right Ventricular Cardiomyopathy in the Nordic countries

Abstract>

Objectives. Diagnostics of patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) are complex, and based on the 2010 Task Force document including different diagnostic modalities. However, recommendations for clinical management and follow-up of patients with ARVC and their relatives are sparse. This paper aims to give a practical overview of management strategies, risk stratification, and selection of appropriate therapies for patients with ARVC and their family members. Design. This paper summarizes follow-up and treatment strategies in ARVC patients in the Nordic countries. The author group represents cardiologists who are actively involved in the Nordic ARVC Registry which was established in 2009, and contains prospectively collected clinical data from more than 590 ARVC patients from Denmark, Norway, Sweden, and Finland. Results. Different approaches of management and follow-up are required in patients with definite ARVC and in genetic-mutation-positive family members. Furthermore, ARVC patients with and without implantable cardioverter defibrillators (ICDs) require different follow-up strategies. Conclusion. Careful follow-up is required in patients with ARVC diagnosis to evaluate the need of anti-arrhythmic therapy and ICD implantation. Mutation-positive family members should be followed regularly for detection of early disease and risk stratification of ventricular arrhythmias.     

Prediction of Life-Threatening Ventricular Arrhythmia in Patients With Arrhythmogenic Cardiomyopathy: A Primary Prevention Cohort Study

Objectives

This study aimed to identify clinical, electrocardiographic (ECG) and cardiac imaging predictors of first-time life-threatening ventricular arrhythmia in patients with arrhythmogenic cardiomyopathy (AC).

The Diagnostic Yield of Brugada Syndrome After Sudden Death With Normal Autopsy

Background

Familial evaluation after a sudden death with negative autopsy (sudden arrhythmic death syndrome; SADS) may identify relatives at risk of fatal arrhythmias.

Right Ventricular Functional Abnormalities in Arrhythmogenic Cardiomyopathy: Association With Life-Threatening Ventricular Arrhythmias

ObjectivesThis study aimed to perform an external validation of the value of right ventricular (RV) deformation patterns and RV mechanical dispersion in patients with arrhythmogenic cardiomyopathy (AC). Secondly, this study assessed the association of these parameters with life-threatening ventricular arrhythmia (VA).BackgroundSubtle RV dysfunction assessed by echocardiographic deformation imaging is valuable in AC diagnosis and risk prediction. Two different methods have emerged, the RV deformation pattern recognition and RV mechanical dispersion, but these have neither been externally validated nor compared.MethodsWe analyzed AC probands and mutation-positive family members, matched from 2 large European referral centers. We performed speckle tracking echocardiography, whereby we classified the subtricuspid deformation patterns from normal to abnormal and assessed RV mechanical dispersion from 6 segments. We defined VA as sustained ventricular tachycardia, appropriate implantable cardioverter-defibrillator therapy, or aborted cardiac arrest.ResultsWe included 160 subjects, 80 from each center (43% proband, 55% women, age 41 ± 17 years). VA had occurred in 47 (29%) subjects. In both cohorts, patients with a history of VA showed abnormal deformation patterns (96% and 100%) and had greater RV mechanical dispersion (53 ± 30 ms vs. 30 ± 21 ms; p < 0.001 for the total cohort). Both parameters were independently associated to VA (adjusted odds ratio: 2.71 [95% confidence interval: 1.47 to 5.00] per class step-up, and 1.26 [95% confidence interval: 1.07 to 1.49]/10 ms, respectively). The association with VA significantly improved when adding RV mechanical dispersion to pattern recognition (net reclassification improvement 0.42; p = 0.02 and integrated diagnostic improvement 0.06; p = 0.01).ConclusionsWe externally validated 2 RV dysfunction parameters in AC. Adding RV mechanical dispersion to RV deformation patterns significantly improved the association with life-threatening VA, indicating incremental value.     

Utility of ECG-gated MDCT to differentiate patients with ARVC/D from patients with ventricular tachyarrhythmias

BackgroundThe accuracy of electrocardiogram-gated CT for diagnosing arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is uncertain.ObjectiveWe propose a comprehensive system for scoring characteristic CT findings to diagnose ARVC/D and discuss its utility.MethodsSeventy-seven patients (mean age, 43.1 years; 48 male) diagnosed with ARVC/D or with suspected ARVC/D on the basis of ventricular tachyarrhythmias underwent CT with and without contrast enhancement. We retrospectively graded characteristic CT findings (fatty tissue, bulging appearance, and dilatation of the right ventricle) as minor (1 point) or major (2 points) and then validated our scoring system’s utility for diagnosing ARVC/D with the use of the modified 2010 Task Force criteria as the reference standard.ResultsWe diagnosed 27 of 77 patients with ARVC/D (23 definite, 4 borderline), observing each CT finding more often in patients with ARVC/D than in patients without ARVC/D: fatty tissue, 74.1% versus 12.0%; bulging appearance, 74.1% versus 34.0%; and RV dilatation, 92.6% versus 44.0%. However, observation of each finding in both groups could cause false positive diagnosis. Recursive partitioning analysis showed the superiority of our CT scoring system over methods that used each CT finding and CT findings without fatty tissue for distinguishing ARVC/D and non-ARVC/D. For overall (definite and borderline) and definite ARVC/D diagnosis, sensitivities were 77.8% and 87.0%, specificities were 96.0% and 94.4%, positive predictive values were 91.3% and 87.0%, negative predictive values were 88.9% and 94.4%, and accuracies were 89.6% and 92.2%, respectively.ConclusionsOur CT scoring system showed excellent diagnostic ability and might aid differentiation of ARVC/D from ventricular tachyarrhythmias.     

Role of genetic testing in arrhythmogenic right ventricular cardiomyopathy/dysplasia

Barahona-Dussault C, Benito B, Campuzano O, Iglesias A, Leung TL, Robb L, Talajic M, Brugada R. Role of genetic testing in arrhythmogenic right ventricular cardiomyopathy/dysplasia.
In a cohort of patients with confirmed or suspected arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D), genetic testing is useful in confirming the diagnosis, particularly in individuals who do not completely fulfil Task Force criteria for the disease, thereby also enabling the adoption of preventive measures in family members. Due to the high percentage of novel mutations that are expected to be identified in ARVC/D, the use of genetic screening technology based on the identification of known mutations seems to have very restricted value. Our results support that the presence of certain genetic variations could play a role in the final phenotype of patients with ARVC/D, where single and compound mutation carriers would have more symptomatic forms of the disease and the polymorphism P366L could be associated to a more benign phenotype.