Hemodynamic Events during the Development of Cyanosis and Heart Failure in a Patient with Large Ventricular Septal Defect
A patient with large ventricular septal defect experienced cardiac failure in childhood but improved and participated vigorously in competitive athletics during adolescence. Subsequently exertional dyspnea gradually developed, followed by increasing cyanosis and cardiac failure.
Repeated cardiac catheterizations during the latter period showed that cardiac output into both the pulmonary and the systemic circuits gradually fell to very low levels while vascular resistance rose progressively. The ratios of flows, pressures, and resistances in the two circuits did not change. Left-to-right shunting always predominated. Right atrial pressure rose but pulmonary artery "wedge" pressure remained unaltered.
Progressive reduction in output from both sides of the heart explained the appearance of reduced arterial oxygen saturation, increased cyanosis, and the manifestations of cardiac failure.
- © 1964 American Heart Association, Inc.