Physiology, diagnosis and clinical profile of the hypoplastic left heart syndrome

• Published in: Progress in pediatric cardiology 1996-02, Vol.5 (1), p.19-22
• Main Author: Rosenthal, Amnon
• Format: Article
• Language: English
• Subjects: Clinical profile; Hypoplasia; Infant; Physiology
• ISSN: 1058-9813; 1558-1519
• DOI: 10.1016/1058-9813(95)00145-X

Whereas multiple and different cardiac abnormalities may be accompanied by hypoplasia of the left heart, the postnatal pathophysiologic changes which accompany these abnormalities are very similar. In the fetus, hypoplasia of the left ventricle does not result in any complications, but the post-natal physiologic changes lead to severe hemodynamic and circulatory complications which in the absence of treatment are fatal. The major physiologic changes are those related to the decrease in pulmonary vascular resistance, spontaneous constriction or closure of the ductus arteriosus, and restriction of the obligatory left-to-right shunt which must exist through an interatrial communication. The clinical features are closely related to the dominance and severity of the physiologic changes and the balance between the systemic and pulmonary vascular resistance. Presentation may be with respiratory distress, congestive heart failure, vascular collapse, or less frequently with severe cyanosis. The presence of mild hypoxemia, normal or reduced Pa CO 2 and very low pH are characteristic features of infants with hypoplastic left heart syndrome. Early post-natal detection of these infants may be enhanced by screening all newborns discharged from the nursery with measurement of systemic arterial oxygen saturations by a pulse volume oximeter.