title: Epidemiological and morphological studies of double-chambered right ventricle in dogs.
abstract: The double-chambered right ventricle (DCRV) is a rare congenital cardiac disease in dogs, and its detailed epidemiological and morphological features are not clearly understood. By investigating the profile, clinical signs, and characteristics of examination findings of eleven dogs with DCRV by means of a retrospective study, we attempted to clarify the epidemiology and morphology of the condition. The study group consisted of nine males and two females. Breeds included Pug (n=3), Miniature Dachshund (n=1), French Bull-dog (n=1), Shiba (n=1), and Retrievers (n=5). The attachment site of the anomalous muscular bundle was continuous with the cardiac apex in nine dogs, and it was attached to the right ventricle free wall in the other two dogs. In dogs with DCRV, at least one of the following conditions was present concurrently: congenital or acquired tricuspid valve regurgitation (TR), ventricular septal defect, and atrial septal defect. Also, the pressure difference between the two chambers increased over time, and progressive right-sided heart failure was observed. In summary, DCRV occurs in small breeds of dog as well as in large breeds of dog and it may be more prevalent in males. The existence of two types of DCRV in dogs was established. Dog with DCRVs will have a high incidence of concurrent cardiac abnormalities. Concurrent TR may be either congenital or acquired. DCRV is a congenital disorder, but the clinical condition progresses as the dog develops.
authors.affiliation: Department of Veterinary Surgery, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Fuchu, Tokyo, Japan. shinndou@lake.ocn.ne.jp
authors.forename: Ryuji
authors.initials: R
authors.lastname: Fukushima
authors.forename: Ryou
authors.initials: R
authors.lastname: Tanaka
authors.forename: Shuji
authors.initials: S
authors.lastname: Suzuki
authors.forename: Rina
authors.initials: R
authors.lastname: Hamabe
authors.forename: Noboru
authors.initials: N
authors.lastname: Machida
authors.forename: Shu
authors.initials: S
authors.lastname: Nakao
authors.forename: Yuto
authors.initials: Y
authors.lastname: Saida
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Takashima
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Matsumoto
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Koyama
authors.forename: Hisashi
authors.initials: H
authors.lastname: Hirose
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Yamane
mesh_terms: D000818:Animals; D004283:Dog Diseases / Q000175:diagnosis* / Q000453:epidemiology / Q000628:therapy; D004285:Dogs; D004452:Echocardiography / Q000662:veterinary; D004562:Electrocardiography / Q000662:veterinary; D005260:Female; D006330:Heart Defects, Congenital / Q000175:diagnosis / Q000453:epidemiology / Q000628:therapy / Q000662:veterinary*; D006352:Heart Ventricles / Q000002:abnormalities* / Q000000981:diagnostic imaging; D008297:Male; D011859:Radiography; D012189:Retrospective Studies; D016896:Treatment Outcome