Publique en esta revista
Información de la revista
Vol. 64. Núm. 6.
Páginas 537-538 (Junio 2011)
Descargar PDF
Más opciones de artículo
Vol. 64. Núm. 6.
Páginas 537-538 (Junio 2011)
Acceso a texto completo
Prenatal Hypertrophic Cardiomyopathy and Neonatal Noonan Syndrome: an Association to Remember
Miocardiopatía hipertrófica intraútero y síndrome de Noonan neonatal: una asociación a recordar
Antonio Sánchez Andrésa,
Autor para correspondencia

Corresponding author:
, Ana Moriano Gutiérreza, José Ignacio Carrasco Morenoa
a Sección de Cardiología Pediátrica, Hospital Infantil La Fe, Valencia, Spain
Información del artículo
Texto completo
Descargar PDF
Figuras (2)
Texto completo

To the Editor,

We present the case of a girl diagnosed with prenatal hypertrophic cardiomyopathy in week 32 of gestation. In this first pregnancy for an older woman, the fetus had a thickened nuchal fold at the 12-week screening; amniocentesis revealed a normal 46, XX karyotype and polyhydramnios. She was born at 38 weeks of gestation with no complications. She was admitted for study, and physical examination revealed dysmorphic and somewhat coarse features, macrocephaly and macrosomia, wide chest and short limbs, low-set ears, wide nasal bridge, hypertelorism, antimongoloid slanting eyes, carp mouth with a marked philtrum and high arched palate, low rear hairline, and a short, wide neck (Figure 1); she also had a variable ejection systolic heart murmur in the first few hours of life. The electrocardiogram (Figure 1) showed biventricular hypertrophy with repolarization changes. A chest X-ray (Figure 1) showed moderate cardiomegaly, and an echocardiogram (Figure 2) confirmed the diagnosis of hypertrophic cardiomyopathy with severe obstruction in the left ventricular outflow tract. Treatment was begun with propranolol, and the patient has remained free of cardiac symptoms or arrhythmias. Screening tests for metabolic diseases were normal, and a molecular genetic test for Noonan's syndrome confirmed a KRAS gene mutation. The family study showed the parents were negative.

Figure 1. Phenotype described. X-ray cardiomegaly. Electrocardiographic alterations.

Figure 2. Echocardiogram: ventricular hypertrophy. Severe subaortic obstruction.

Noonan's syndrome is associated with a wide variety of signs and symptoms due to multi-organ involvement. It has some very characteristic signs, such as short stature, while others, although less striking, also can lead to suspicion of the diagnosis. These include a short, wide neck; ears set low and towards the rear, hypertelorism with antimongoloid slanting eyes, epicanthus, ptosis, retromicrognathia and a wide philtrum. There can also be chest and back deformities, joint laxity, chryptorchidism, delayed puberty, coagulation problems, etc. Most patients have normal intelligence, although 15% to 35% have slight retardation, and language problems are common.1

Mutations have been described in 4 genes: PTPN11 (50%), SOS1 (20%), RAF1 (15%) and KRAS (5%); between 10% and 15% are idiopathic.2 In the 35 cases of KRAS mutation, phenotype was more severe than in the other genes.3

Heart defects are very common in this syndrome and their severity varies. The most common are stenotic pulmonary valves (60%) and hypertrophic cardiomyopathies (HCM) (20%). HCM is a primary disease of the heart muscle characterized by hypertrophy of one (generally left) or both ventricles with no cardiac or systemic disease to justify it. Although most cases are idiopathic, several disorders must be ruled out in newborns, the most common being diabetic fetopathies. It may be associated with polymalformation syndromes such as Noonan,4 LEOPARD, Beckwith-Weidemann, or Barth syndromes, and with metabolic diseases, and it is necessary to rule out deposit diseases (glycogenosis, mucopolysaccharidosis, oligosaccharidosis, sphingolipidosis, etc.), energy metabolism disorders (fatty acid oxidative deficiency and carnitine deficiency) and neuromuscular syndromes (Friedrich ataxia5).

The age of presentation of HCM varies greatly and depends above all on the causal mutation, although in many cases this is part of the disease's natural evolution; in older patients, it develops with varying intensities.6 Echocardiography provides a definitive diagnosis, and electrocardiogram monitoring is necessary for the early detection of ventricular arrhythmias, which are sometimes precursors of episodes of sudden cardiac death (SCD), the main cause of mortality. The earlier the age of presentation, the higher the risk of SCD, as these patients also have worse treatment options.7

Beginning pharmacological treatment is recommended in asymptomatic children with obstructive SCD and significant left ventricular outflow tract gradients, and an appropriate stratification of the risk of SCD must be carried out and genetic advice given to parents.8

Corresponding author:

Van der Burgt I..
Noonan syndrome..
Orphanet J Rare Dis. , 14 (2007), pp. 2-4
Gibson W..
Noonan syndrome in a premature infant with hypertrophic cardiomyopathy and death in infancy..
J Natl Med Assoc. , 97 (2005), pp. 805-807
Lo FS, Lin JL, Kuo MT, Chiu PC, Shu SG, Chao MC, et al., et al.
Noonan syndrome caused by germline KRAS mutation in Taiwan: report of 2 patients and a review of the literature..
Eur J Pediatr. , 168 (2009), pp. 919-923
Faienza MF, Giordani L, Ferraris M, Bona G, Cavallo L..
PTPN11 gene mutation and severe neonatal hypertrophic cardiomyopathy: what is the link?..
Pediatr Cardiol. , 30 (2009), pp. 1012-1015
Bonnet D, de Lonlay P, Gautier I..
Efficiency of metabolic screening in childhood cardiomyopathies..
Eur Heart J. , 19 (1998), pp. 790-793
Zubeldia Sánchez J, Cabrera Duro A, Sánchez Obregon M, Pilar Uribe J, Sarrionandia Uribelarrea M, Sebastian Ruiz MJ, et al., et al.
Cardiopathy in Noonan syndrome. Review of 29 cases..
An Esp Pediatr. , 30 (1989), pp. 104-108
Sonesson SE, Fouron JC, Lessard M..
Intrauterine diagnosis and evolution of a cardiomyopathy in a fetus with Noonan's syndrome..
Acta Paediatr. , 81 (1992), pp. 368-370
Colan SD, Lipshultz SE..
Epidemiology and causes-specific outcome of hypertrophic cardiomyopathy in children..
Circulation. , 115 (2007), pp. 773-781
Revista Española de Cardiología

Suscríbase a la newsletter

Ver histórico de newsletters
Opciones de artículo
es en

¿Es usted profesional sanitario apto para prescribir o dispensar medicamentos?

Are you a health professional able to prescribe or dispense drugs?