The Cardiac Society of Australia and New Zealand Position Statement on the Diagnosis and Management of Arrhythmogenic Right Ventricular Cardiomyopathy (2019 Update)

Arrhythmogenic right ventricular cardiomyopathy characterized by recurrent syncope during exercise: A case report

BACKGROUND

Arrhythmogenic right ventricular (RV) cardiomyopathy is a rare and currently underrecognized cardiomyopathy characterized by the replacement of RV myocardium by fibrofatty tissue. It may be asymptomatic or symptomatic (palpitations or syncope) and may induce sudden cardiac death, especially during exercise. To prevent adverse events such as sudden cardiac death and heart failure, early diagnosis and treatment of arrhythmogenic RV cardiomyopathy (ARVC) are crucial. We report a patient with ARVC characterized by recurrent syncope during exercise who was successfully treated with combined endocardial and epicardial catheter ablation.

CASE SUMMARY

A 43-year-old man was referred for an episode of syncope during exercise. Previously, the patient experienced two episodes of syncope without a firm etiological diagnosis. An electrocardiogram obtained at admission indicated ventricular tachycardia originating from the inferior wall of the right ventricle. The ventricular tachycardia was terminated with intravenous propafenone. A repeat electrocardiogram showed a regular sinus rhythm with negative T waves and a delayed S-wave upstroke from leads V1 to V4. Cardiac magnetic resonance imaging showed RV free wall thinning, regional RV akinesia, RV dilatation and fibrofatty infiltration (RV ejection fraction of 38%). An electrophysiological study showed multiple inducible ventricular tachycardia as of a focal mechanism from the right ventricle. Endocardial and epicardial voltage mapping demonstrated scar tissue in the anterior wall, free wall and posterior wall of the right ventricle. Late potentials were also recorded. The patient was diagnosed with ARVC and treated with combined endocardial and epicardial catheter ablation with a very satisfactory follow-up result.

CONCLUSION

Clinicians should be aware of ARVC, and further workup, including imaging with multiple modalities, should be pursued. The combination of epicardial and endocardial catheter ablation can lead to a good outcome.

Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) Probably Caused by DSG2 p.Val149Ile Mutation as Genetic Background When Carrying with Heterozygous PRRT2 p.Arg217ProfsTer8 Mutation: A Case Report

Background

ARVC is a rare genetic-related disease characterized by fibrous fat replacement in the ventricular myocardium, caused by mutations in genes encoding for the desmosomal proteins, such as the desmoglein-2 gene (DSG2). It is reported in the literature that other genetic factors may play a role in disease penetrance. Herein, we report a Chinese proband with ARVC, which was probably caused by DSG2 p.Val149Ile mutation as genetic background when carrying heterozygous PRRT2 p.Arg217ProfsTer8 mutation.

Case Presentation

A 17-year-old male with a history of paroxysmal kinesigenic dyskinesia (PKD) presented to the hospital for syncope induced by ventricular tachycardia. According to relevant clinical data and the diagnostic criteria of ARVC, a precise positive diagnosis of ARVC was finally made. Gene testing revealed that the patient carried a DSG2 heterozygous missense mutation (NM_001943: exon5: c.445G>A, p.Val149Ile) as well as frameshift mutation of PRRT2 (NM_001256442: exon2: p. Arg217Profs Ter8).

Conclusion

This is the first time to report a Chinese proband with ARVC and a history of PKD carrying both DSG2 p. val149ile mutation and PRRT2 p. Arg217ProfsTer8 mutation, which can provide a new direction for gene screening of patients with ARVC and further supplements for its diagnostic criteria.