Cardiomyopathy in Noonan's syndrome. Report of 3 cases.

Cardiovascular malformations in patients with a Turner's phenotype and a normal chromosomal karyotype (Noonan's syndrome) have been reported in several recent publications (Noonan and Ehmke, I963; Chaves-Carballo and Hayles, I966; Celermajer, Bowdler, and Cohen, I968; Noonan, I968). Congenital heart disease is present in 48 per cent (Smith, I970) of the patients, the most common abnormality being valvar pulmonary stenosis (Chaves-Carballo and Hayles, I966; Noonan, 1968). Supravalvar and pulmonary arterial branch stenosis (Nora and Sinha, I968), atrial septal defect (ChavesCarballo and Hayles, I966; Noonan, I968), and a persistent ductus arteriosus (Chaves-Carballo and Hayles, I966; Noonan, I968) are also frequently observed. Other infrequent cardiac lesions include aortic valvar stenosis (Chaves-Carballo and Hayles, I966; Nora and Sinha, I968), Ebstein's malformation (Wright, Sumnuitt, and Ainger, I968), ventricular septal defect (Chaves-Carballo and Hayles, I966), tetralogy of Fallot (Chaves-Carballo and Hayles, I966), truncus arteriosus (Warkany, 197I), and coarctation of the aorta (Chaves-Carballo and Hayles, I966). Eccentric left ventricular hypertrophy has been recently described (Ehlers et al., 1972) in familial and sporadic cases of Turner's phenotype with normal karyotype. This report extends these observations further and describes obstructive and nonobstructive hypertrophic cardiomyopathy in patients with Noonan's syndrome.