skip to main content

DSP Truncating Variant Management — EECC MCQ

Instant feedback + full explanation. One question, done properly.

HardCardiomyopathyDSP Truncating Variant ManagementEECC

A 55-year-old man with suspected arrhythmogenic cardiomyopathy presents with palpitations. ECG shows T-wave inversion in V1-V3 and epsilon waves. CMR shows fibrofatty replacement of the RV with aneurysmal dilatation. Genetic testing reveals a DSP (desmoplakin) truncating variant. How does this genotype affect management?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: C — DSP truncating variants are associated with a high arrhythmic risk and LV involvement (arrhythmogenic LV cardiomyopathy/ALVC phenotype) — ICD should be considered at a lower LVEF threshold than standard DCM due to the arrhythmogenic genotype classification

Desmoplakin (DSP) truncating variants are among the most important desmosomal mutations, associated with a distinct phenotype: (1) left-dominant or biventricular arrhythmogenic cardiomyopathy (ALVC/biventricular AC) — not just classic ARVC; (2) high arrhythmic risk disproportionate to LV dysfunction (similar to LMNA, FLNC, PLN — 'arrhythmogenic genotypes'); (3) characteristic ring-like subepicardial LGE on CMR; (4) may present with acute myocarditis-like episodes. The 2023 ESC Cardiomyopathy Guidelines classify DSP alongside LMNA, FLNC, PLN, and RBM20 as genotypes where standard LVEF-based ICD thresholds are insufficient. ICD should be considered at LVEF >35% when additional risk factors (NSVT, extensive LGE, syncope) are present. Exercise restriction and cascade genetic screening are recommended.

Reference: ESC (2023): Cardiomyopathies Guidelines