A case of type 3 Ehlers-Danlos syndrome with associated mitral valve prolapse, right bundle-branch block, and left anterior fascicular block was studied, including His bundle electrocardiography and echocardiography. Mitral valve prolapse and HV prolongation were reported. The present study suggests that the basic underlying collagen defect in this syndrome is responsible for these findings, and that the association may be more widespread in the syndrome than currently acknowledged. The possibility also is considered that the connective tissue abnormalities of Ehlers-Danlos syndrome involving the heart may be the cause of some cases of idiopathic conduction system disease or valvular insufficiency.
(Arch Intern Med 137:1227-1231, 1977)