title: Definition of inseparably fused ventricular myocardium in thoracopagus: fetal echocardiographic utility and pathologic refinement.
abstract: Correlative echocardiographic and pathological findings in a thoracopagus with conjoined hearts are reported. One twin had tricuspid atresia with discordant atrioventricular connections and concordant ventriculoarterial connections. The morphologic right ventricle was hypoplastic and there was a large muscular ventricular septal defect. The other twin had hypoplasia of the mitral valve anulus and left ventricle with double-outlet right ventricle and pulmonary valve atresia. The tricuspid valve was severely insufficient in part because of a large orifice and redundant, elongated leaflets with abnormal chordal attachments. The left ventricles of these two twins shared a perforated common "free wall" with at least two large defects allowing mixing of the circulations at that level. Not all anatomic details were established conclusively by fetal echocardiography; however, sufficient diagnostic information was obtained to support a decision not to aggressively resuscitate these twins after elective cesarean delivery at 31 weeks' gestation.
authors.affiliation: Department of Pediatrics, University of Nebraska Medical Center, Omaha 68198.
authors.forename: D A
authors.initials: DA
authors.lastname: Danford
authors.forename: B M
authors.initials: BM
authors.lastname: McManus
authors.forename: S M
authors.initials: SM
authors.lastname: Nielsen
authors.forename: M G
authors.initials: MG
authors.lastname: Levine
authors.forename: H W
authors.initials: HW
authors.lastname: Needelman
mesh_terms: D000328:Adult; D004452:Echocardiography; D005260:Female; D005318:Fetal Heart / Q000002:abnormalities* / Q000000981:diagnostic imaging; D006330:Heart Defects, Congenital / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy; D014428:Twins, Conjoined / Q000473:pathology*; D016216:Ultrasonography, Prenatal