Myocardial infarcts in infants and children. I. A necropsy study in congenital heart disease

Abstract

Myocardial infarction is not rare in infants and children. It is common in congenitalheart disease even in the absence of gross coronary anomaly or pathology. Infarcts were found in 33 of 44 hearts in a series including cases of total anomalous venous return, aortic valvular stenosis, pulmonary valvular stenosis, and complete transposition of the great arteries. All hearts of patients older than 3 months showed infarcts, usually located in the subendocardial myocardium and in the papillary muscles of the hypertrophied ventricle. Decreased coronary perfusion and desaturation of systemic blood probably affect both ventricles. The relative coronary insufficiency associated with increased myocardial mass may be responsible for the preferential localization of infarcts in one ventricle: the left in aortic stenosis, the right in pulmonic stenosis and anomalous pulmonary venous return. Only minor coronary artery lesions were found in the series and these did not correlate with the side or severity of infarction. The papillary muscle infarcts may affect the normal function of both atrioventricular valves. A review of electrocardiographic data showed that about half of the infarcts might have been diagnosed clinically. Myocardial infarction is not rare in infants and children. It is common in congenitalheart disease even in the absence of gross coronary anomaly or pathology. Infarcts were found in 33 of 44 hearts in a series including cases of total anomalous venous return, aortic valvular stenosis, pulmonary valvular stenosis, and complete transposition of the great arteries. All hearts of patients older than 3 months showed infarcts, usually located in the subendocardial myocardium and in the papillary muscles of the hypertrophied ventricle. Decreased coronary perfusion and desaturation of systemic blood probably affect both ventricles. The relative coronary insufficiency associated with increased myocardial mass may be responsible for the preferential localization of infarcts in one ventricle: the left in aortic stenosis, the right in pulmonic stenosis and anomalous pulmonary venous return. Only minor coronary artery lesions were found in the series and these did not correlate with the side or severity of infarction. The papillary muscle infarcts may affect the normal function of both atrioventricular valves. A review of electrocardiographic data showed that about half of the infarcts might have been diagnosed clinically.