arrhythmogenic right ventricular cardiomyopathy

Imagine a section of healthy muscle wall slowly being replaced by fat and fibrous scar, like good cloth being patched with stiff, frayed material. In arrhythmogenic right ventricular cardiomyopathy this happens mainly in the right ventricle: muscle cells die and are replaced by fatty and scar tissue. The patchy, electrically irritable wall becomes a launchpad for dangerous fast rhythms.

It is largely a genetic disease, often caused by mutations in the proteins (desmosomes) that glue heart-muscle cells together; under repeated mechanical stress these weak junctions fail and cells are lost. Because the changes favour electrical chaos, the first sign can be palpitations, fainting during exertion, or even sudden cardiac death in a young, otherwise healthy person — frequently an athlete.

Over time the right ventricle can enlarge and weaken, and the left ventricle may be involved too, so the older name emphasising only the right side is somewhat narrow. Management focuses on preventing sudden death — restricting intense exercise, using antiarrhythmic drugs, performing ablation, and often implanting a defibrillator — and on screening family members who may carry the same gene.