Which of the following clinical pathophysiologic manifestations are consistent with a large ventricular septal defect (VSD)?
I. The majority of the blood flow are shunted from left right to right left.
II. Shunting typically occurs during ventricular diastole, which causes left atrial enlargement.
III. Chest radiography reveals an enlarged cardiac silhouette and increased pulmonary vascular markings, increasing pulmonary blood flow.
IV. Thickening and fibrosing of the pulmonary veins develop, decreasing pulmonary artery pressure.

Question

Quizplus · Accepted Answer

The pathophysiology of the VSD depends upon its size. Small VSDs, particularly those within the muscular septum, may close spontaneously and remain asymptomatic. Large and unrestrictive (i.e., there is no pressure difference between the right and left ventricle) creates a large left-to-right shunt and pulmonary arterial hypertension. Because, unlike ASDs, the pulmonary artery pressure in the presence of an unrestrictive VSD is equal to that in the aorta, patients with unrestrictive VSD may develop signs of pulmonary overcirculation and pulmonary edema more quickly than one with an ASD, even when the shunt fraction is the same. Over time, patients with unrestrictive and unrepaired VSDs may develop muscularization of the pulmonary arteries, which may lead to pulmonary hypertension. If the pulmonary vascular resistance nears that of the systemic vascular resistance, the left-to-right shunt may reverse to a right-to-left shunt, a condition known as Eisenmenger syndrome.

Which of the Following Clinical Pathophysiologic Manifestations Are Consistent with a Large