Clinical Characteristics And Genetic Screening Of Arrhythmogenic Right Ventricular Cardiomyopathy

PARTâ… : Clinical Characteristics of Arrhythmogenic Right Ventricular CardiomyopathyObjective:Arrhythmogenic right ventricular cardiomyopathy(ARVC) is an inherited cardiomyopathy characterized by right ventricular dysfunction and ventricular arrhythmias.The purpose of this study was to describe the presentation,clinical features,survival,and natural history of ARVC in Chinese patients.Methods and Results:The patient population included 64 ARVC patients(39male; median age 42 years).The most common presenting symptoms were palpitations, dyspnea in 77%and 26%of patients,respectively.55 patients presented as ventricular arrhythmia or syncope,while 9 patients presented as heart dysfunction.The median time between first presentation and diagnosis was 8.2 years.25 patients received radiofrequency catheter ablation(RFCA),of which 22 patients achieved immediate success.Implantable cardioverter defibrillators(ICD) were implanted in 4 patients,2 of whom received an appropriate ICD discharge.2 patients had a heart surgery.33 patients were solely on drug therapy.3 patients died at presentation and one during follow-up,all due to heart failure.Conclusion:There is a wide variation in presentation and course of ARVC patients. Diagnosis is often delayed.Premature ventricular beats interval dispersion(PVCID) in patients with multifocal premature ventricular beats is more remarkable,and these patients is more likely to accompany ventricular tachycardia though with a slower tachycardia rate.Patients with heart dysfunction had a higher mortality rate.Sotalol has the best efficacy among all anti-arrhythmic drugs.RFCA is effective in selected patients.Patients with a larger PVCID or lower ejection fraction(EF) are more refractory to therapy. PARTâ…¡: Genetic Screening of Arrhythmogenic Right Ventricular CardiomyopathyObjective:Desmosome gene mutations have been reported in patients with arrhythmogenic right ventricular cardiomyopathy(ARVC).However,there are hardly any genetic studies in Asians.This study studied desmosome gene mutations in ARVC patients in China.Methods:2 familial and 10 sporadic ARVC patients were reviewed and genomic DNA was obtained from peripheral blood samples.Mutation screening in plakophilin-2(JUP),desmoglein-2(DSG2) and desmocollin-2(DSC2) genes was performed using polymerase chain reaction(PCR) and DNA sequencing techniques.Results:Among the 12 patients,mutations in the desmosome genes were identified in 11 of the 12 patients(11 with a DSG2 mutation and 3 with a JUP mutation).All mutations were novel(two patients had a DSG2 double mutation).The mutation types were all missense.Conclusion:Patients with ARVC in China had similar cardiac manifestations as reported in the Western literature.Nearly all patients had desmosome gene missense mutations.