Mitsuaki Isobe, MD; Toru Oka, MD; Hiroaki Takenaka, MD; Hiroshi Imamura, MD; Osamu Kinoshita, MD; Hiroshi Kasanuki, MD 1 ; Morie Sekiguchi, MD

Abstract
A family with sick sinus syndrome is presented: a mother and her 2 daughters affected with sinus node dysfunc-tion. Electrophysiological studies revealed abnormal atrioventricular conduction in the 2 daughters. All 3 indi-viduals were implanted with a permanent pacemaker to relieve their symptoms. Endomyocardial biopsy from the right ventricle of one daughter showed disarrangement, degeneration, myocyte necrosis and interstitial fibrosis suggestive of myocardial disease.
(Jpn Circ J 1998; 62: 788-790)

Key Words: Atrioventricular block; Cardiomyopathy; Genetic disease; Sick sinus syndrome

Mailing address: Mitsuaki Isobe, MD, The First Department of Internal Medicine, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan. E-mail: isobemi@gipac.shinshu-u.ac.jp