Complete Atrioventricular Block Complicating Mitral Infective Endocarditis Caused by Streptococcus Agalactiae.
BACKGROUND Infective endocarditis (IE) involving the mitral valve can but rarely lead to complete atrioventricular block (CAVB). CASE REPORT A 74-year-old man with a history of infective endocarditis caused by Streptococcus gordonii (S. gordonii) presented to our emergency room with fever and loss of appetite, which had lasted for 5 days. On admission, results of serologic tests pointed to severe infection. Electrocardiography showed normal sinus rhythm with first-degree atrioventricular block and incomplete right bundle branch block, and transthoracic echocardiography and transesophageal echocardiography revealed severe mitral regurgitation caused by posterior leaflet perforation and 2 vegetations (5 mm and 6 mm) on the tricuspid valve. The patient was initially treated with ceftriaxone and gentamycin because blood and cutaneous ulcer cultures yielded S. agalactiae. On hospital day 2, however, sudden CAVB requiring transvenous pacing occurred, and the patient's heart failure and infection worsened. Although an emergent surgery is strongly recommended, even in patients with uncontrolled heart failure or infection, surgery was not performed because of the Child-Pugh class B liver cirrhosis. Despite intensive therapy, the patient's condition further deteriorated, and he died on hospital day 16. On postmortem examination, a 2×1-cm vegetation was seen on the perforated posterior mitral leaflet, and the infection had extended to the interventricular septum. Histologic examination revealed extensive necrosis of the AV node. CONCLUSIONS This rare case of CAVB resulting from S. agalactiae IE points to the fact that in monitoring patients with IE involving the mitral valve, clinicians should be aware of the potential for perivalvular extension of the infection, which can lead to fatal heart block.
Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
Masaru
M
Arai
Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
Koichi
K
Nagashima
Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
Mahoto
M
Kato
Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
Naotaka
N
Akutsu
Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
Misa
M
Hayase
Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
Kanako
K
Ogura
Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
Yukino
Y
Iwasawa
Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
Yoshihiro
Y
Aizawa
Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
Yuki
Y
Saito
Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
Yasuo
Y
Okumura
Department of Pathology, Nihon University School of Medicine, Tokyo, Japan.
Haruna
H
Nishimaki
Department of Pathology, Nihon University School of Medicine, Tokyo, Japan.
Shinobu
S
Masuda
Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
Astushi
A
Hirayama
D000368:Aged; D054537:Atrioventricular Block / Q000175:diagnosis / Q000209:etiology*; D004697:Endocarditis, Bacterial / Q000150:complications* / Q000473:pathology; D017809:Fatal Outcome; D006801:Humans; D008297:Male; D013290:Streptococcal Infections / Q000150:complications* / Q000473:pathology; D013292:Streptococcus agalactiae