Fulminant Biventricular Desmoplakin Cardiomyopathy With a Myocarditis-Like Presentation

Desmoplakin (DSP) cardiomyopathy is an inherited cardiomyopathy that may present with a myocarditis-like phenotype, delaying diagnosis and risk stratification.

A previously healthy 23-year-old man developed rapidly progressive heart failure following 2 months of intermittent fever. Evaluation revealed severe biventricular systolic dysfunction (left ventricular ejection fraction, 11%), ventricular ectopy with nonsustained ventricular tachycardia, and cardiac magnetic resonance showing extensive circumferential subepicardial ring-like fibrosis. Infectious, autoimmune, inflammatory, infiltrative, and toxic causes were excluded. Whole-exome sequencing identified a likely pathogenic truncating DSP variant (c.2521C>T; p.Gln841Ter). Despite guideline-directed therapy and anticoagulation for right ventricular thrombi, he developed refractory ventricular tachycardia and died of electrical storm.

DSP cardiomyopathy can mimic acute myocarditis and carries substantial arrhythmic and heart failure risk.

Myocarditis-like presentations with ventricular arrhythmias should prompt evaluation for DSP cardiomyopathy. Early genetic diagnosis may facilitate timely arrhythmic and advanced heart failure risk stratification.