単たん心しん室しつMeanings1noununiventricular heart; single ventricle defectmedicineMedical term for a congenital heart defect where the heart has only one functional ventricle.単たん心しん室しつは先せん天てん性せい心しん疾しっ患かんの一ひとつです。Univentricular heart is one of the congenital heart diseases.