Cardiomyopathy in cystic fibrosis: lymphoedema of the heart with focal myocardial fibrosis.

Cardiomyopathy in cystic fibrosis (CF) is an unusual heart disease, mainly characterized by a multifocal fibrosis of the left ventricle. The disorder chiefly occurs in the age group of 1-2 years and leads to fatal cardiac failure. The causal pathogenesis of the disease has not been discovered up to now. In two cases of CF-associated cardiomyopathy we found an oedema (mainly lymphoedema) of the myo- and epicardium and a lymph stasis in lymph vessels and lymph nodes of the heart. Based on a comparative study using animal models we speculate that a) CF may be complicated by a disorder of cardiac lymph circulation, and b) chronic cardiac lymphoedema of the heart in CF can cause focal myocardial damage with fibrosis.