ORIGINAL ARTICLE Acute Progressive Mitral Regurgitation Resulting From Chordal Rupture in Infants Hiroko Asakai • Yukihiro Kaneko • Masahide Kaneko • Yasushi Misaki • Ikuya Achiwa • Yasutaka Hirata • Hitoshi Kato Received: 9 November 2010 / Accepted: 9 February 2011 / Published online: 2 March 2011 Ó Springer Science+Business Media, LLC 2011 Abstract This report describes six previously healthy infants with acute mitral valve chordal rupture. Although their initial symptoms were mild respiratory distress and fever, all the infants presented with acute progressive left heart failure and required urgent surgical repair. Mitral valve annuloplasty and mitral valve replacement were performed (for three patients each). Two patients died, both of whom had cardiac arrest and required resuscitation before surgery. Histologic examination of excised mitral valve leaflets showed infiltration of gram-positive bacteria in these two patients. All the patients were 4–6 months old, which may suggest underlying congenital factors. The authors believe early diagnosis and surgery are crucial as a life-saving measure for infants with acute mitral valve chordal rupture. Keywords Acute mitral regurgitation Á Infants Á Mitral valve chordal rupture In adults, postischemic papillary muscle rupture frequently results in acute mitral regurgitation and life-threatening cardiac failure. The literature contains very few reports describing pediatric cases of spontaneous mitral valve chordal rupture [1, 2, 3, 5, 7, 8, 9, 12, 13]. Therefore, the etiology and clinical course for infants are less well understood than for adults. Most frequently, the rapid progression of disease after the onset of initial symptoms results in severe acute congestive heart failure. We report the cases of six infants who presented with acute mitral regurgitation associated with chordal rupture. Patients and Methods We retrospectively reviewed the medical records for all cases of acute mitral regurgitation due to chordal rupture in infants at our institution from 2003 to 2009. Six infants (four boys and two girls) were identified and included in this study. The median age of the infants was 5.3 months (range, 4–6 months), and their mean body weight was 6.7 kg (range, 6.0–7.2 kg). The follow-up period ranged from 10 months to 7 years (median, 12 months). Interestingly, four of the six infants had hospital stays during the years 2008 and 2009. The collected data included age, clinical findings before surgery, echocardiographic data, operative findings, and the infant’s condition at follow-up evaluation. The echo- cardiographic information included the severity of mitral regurgitation, the presence and localization of mitral valve prolapse, the left ventricular diastolic diameter, and the ejection fraction. Results The clinical manifestations and the examination results of the patients at admission are shown in Table 1. All the patients were previously healthy infants, and only one patient (case 3) had a history of Kawasaki disease, 3 weeks before the onset of mitral regurgitation. This patient did not exhibit cardiac complications, such as coronary artery lesions, during the acute phase of illness. Almost all the patients presented with fever and mild respiratory distress but were initially in good general condition. H. Asakai Á Y. Kaneko Á M. Kaneko Á Y. Misaki Á I. Achiwa Á Y. Hirata Á H. Kato (&) Division of Cardiology and Pediatric Cardiovascular Surgery, National Medical Center for Children and Mothers, 2-10-1 Okura, Setagaya-ku, Tokyo 157-8535, Japan e-mail: kato-ht@ncchd.go.jp 123 Pediatr Cardiol (2011) 32:634–638 DOI 10.1007/s00246-011-9939-2