A CLINICAL PERSPECTIVE IN THE DIAGNOSIS OF CONGENITAL HEART DISEASE

Abstract

The pediatric clinician enjoys a responsible position in the evaluation and management of cardiac problems in early life. The diagnosis of congenital heart disease is facilitated by an understanding of the functional meaning of cyanosis, the physical work of the heart and its chambers, and the significance of the pulmonary vascular bed. Medical history and physical findings may be interpreted to suggest the presence or absense of a shunt, its predominant direction and gross magnitude, and its effect on volume flow and pressure in the pulmonary circulation. Similarly, many obstructive lesions and anomalous vascular arrangements may be identified, localized and their severity grossly evaluated from historic and physical observations. A malformation is significant to the extent that circulatory function is disturbed. The resulting stresses are manifest as clinical abnormality. Clinical evaluation incorporating appreciation of abnormal function leads logically to differential identification of anatomic alternatives. Innocent murmurs, commonly a cause of needless parental anxiety and iatrogenic cardiac disability, may be confidently identified in large majority by their own physical characteristics. Electrocardiographic and roentgenographic study are essential for complete evaluation. Complex and severe cases may require the skill of a consultant and the assistance of definitive investigative procedures, particularly if the differential diagnosis includes an operable malformation. Indications for cardiac catheterization and angiographic study may vary, but indiscriminate use at any age is discouraged. Even when such methods are necessary, searching clinical appraisal is required in order to define the most profitable direction and optimum time for study. For simpler problems, such procedures may be unnecessary and even misleading as well as significantly hazardous and expensive. Diagnosis is often most difficult and most critical in early infancy, partly because of characteristics of circulatory function peculiar to this period, partly because of the larger number of bizarre, complex and lethal malformations encountered.