Isao Shiraishi1, Kunihiro Nishimura2, Heima Sakaguchi2, Tadaaki Abe2, Masataka Kitano2, Kenichi Kurosaki2, Hitoshi Kato2, Toshio Nakanishi2, Hiroyuki Yamagishi2, Koichi Sagawa2, Yoshihiko Ikeda2, Takayuki Morisaki2, Takaya Hoashi2, Koji Kagisaki2, Hajime Ichikawa2. 1. From the Department of Pediatric Cardiology, National Cerebral and Cardiovascular Center, Osaka, Japan (I.S., H.S., T.A., M.K., K. Kurosaki); the Department of Preventive Cardiology, National Cerebral and Cardiovascular Center, Osaka, Japan (K.N.); the Department of Cardiology, National Center for Child Health and Development, Tokyo, Japan (H.K.); the Department of Pediatric Cardiology, Tokyo Women's Medical University, Tokyo, Japan (T.N.); the Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan (H.Y.); the Department of Cardiology, Fukuoka Children's Hospital, Fukuoka, Japan (K.S.); the Department of Clinical Pathology, National Cerebral and Cardiovascular Center, Osaka, Japan (Y.I.); the Department of Bioscience and Genetics, National Cerebral and Cardiovascular Center, Osaka, Japan (T.M.); and the Department of Pediatric Cardiac Surgery, National Cerebral and Cardiovascular Center, Osaka, Japan (T.H., K. Kagisaki, H.I.). shiraishi.isao.hp@ncvc.go.jp. 2. From the Department of Pediatric Cardiology, National Cerebral and Cardiovascular Center, Osaka, Japan (I.S., H.S., T.A., M.K., K. Kurosaki); the Department of Preventive Cardiology, National Cerebral and Cardiovascular Center, Osaka, Japan (K.N.); the Department of Cardiology, National Center for Child Health and Development, Tokyo, Japan (H.K.); the Department of Pediatric Cardiology, Tokyo Women's Medical University, Tokyo, Japan (T.N.); the Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan (H.Y.); the Department of Cardiology, Fukuoka Children's Hospital, Fukuoka, Japan (K.S.); the Department of Clinical Pathology, National Cerebral and Cardiovascular Center, Osaka, Japan (Y.I.); the Department of Bioscience and Genetics, National Cerebral and Cardiovascular Center, Osaka, Japan (T.M.); and the Department of Pediatric Cardiac Surgery, National Cerebral and Cardiovascular Center, Osaka, Japan (T.H., K. Kagisaki, H.I.).
Abstract
BACKGROUND: Recently, infant cases of acute heart failure attributable to rupture of the mitral chordae tendineae have been reported. However, little is known about the pathogenesis and clinical course of this condition. METHODS AND RESULTS: Ninety-five children with rupture of mitral chordae tendineae were identified in nationwide surveys of Japan diagnosed from 1995 to 2013. The clinical manifestations, management strategies, and prognosis were investigated. Eighty-one (85%) patients were between 4 and 6 months (median, 5 months) of age. In 63 (66%) patients, rupture occurred during the spring or summer. The underlying conditions before rupture included Kawasaki disease (10 cases), maternally derived anti-SSA antibodies (2 cases), and infective endocarditis (1 case). Surgery was performed in 80 patients (94 operations), and the final operations included plasty of mitral chordae in 52 cases and mechanical valve replacement in 26 cases. The histopathologic examinations of the mitral valves and chordae (n=28) revealed inflammatory reactions with predominant mononuclear cell infiltration in 18 cases (64%) and increased fibrous and myxoid tissue in 11 cases (39%), suggesting that nonbacterial infectious or autoimmune endocarditis and myxoid changes are involved in the pathogenesis. Eight patients (8.4%) died before (n=6) and shortly after (n=2) the operation, and significant neurological complications persisted in 10 cases (11%). CONCLUSIONS: Acute heart failure attributable to rupture of the mitral chordae tendineae in infants is a unique disease resulting from diverse causes. This condition should be recognized as a significant cardiovascular disorder that may cause sudden onset of cardiogenic shock and death in infants.
BACKGROUND: Recently, infant cases of acute heart failure attributable to rupture of the mitral chordae tendineae have been reported. However, little is known about the pathogenesis and clinical course of this condition. METHODS AND RESULTS: Ninety-five children with rupture of mitral chordae tendineae were identified in nationwide surveys of Japan diagnosed from 1995 to 2013. The clinical manifestations, management strategies, and prognosis were investigated. Eighty-one (85%) patients were between 4 and 6 months (median, 5 months) of age. In 63 (66%) patients, rupture occurred during the spring or summer. The underlying conditions before rupture included Kawasaki disease (10 cases), maternally derived anti-SSA antibodies (2 cases), and infective endocarditis (1 case). Surgery was performed in 80 patients (94 operations), and the final operations included plasty of mitral chordae in 52 cases and mechanical valve replacement in 26 cases. The histopathologic examinations of the mitral valves and chordae (n=28) revealed inflammatory reactions with predominant mononuclear cell infiltration in 18 cases (64%) and increased fibrous and myxoid tissue in 11 cases (39%), suggesting that nonbacterial infectious or autoimmune endocarditis and myxoid changes are involved in the pathogenesis. Eight patients (8.4%) died before (n=6) and shortly after (n=2) the operation, and significant neurological complications persisted in 10 cases (11%). CONCLUSIONS:Acute heart failure attributable to rupture of the mitral chordae tendineae in infants is a unique disease resulting from diverse causes. This condition should be recognized as a significant cardiovascular disorder that may cause sudden onset of cardiogenic shock and death in infants.