Eisenmenger syndrome is characterized by which hemodynamic change?

Eisenmenger syndrome is characterized by which hemodynamic change?

• A. Development of a right-to-left shunt due to pulmonary hypertension without shunt reversal
• B. Reversal of left-to-right shunt due to pulmonary vascular remodeling
• C. Isolated pulmonary hypertension without shunt changes
• D. Spontaneous closure of the septal defect

Answer: (B)

Eisenmenger syndrome centers on a reversal of the flow across a congenital defect due to remodeling of the pulmonary vessels. When a large left-to-right shunt (such as from a VSD, PDA, or ASD) causes high blood flow and pressure in the lungs, the pulmonary vessels progressively hypertrophy and narrow (medial hypertrophy and intimal hyperplasia). This raises pulmonary vascular resistance until it exceeds systemic vascular resistance, flipping the shunt to right-to-left. That reversal is the hallmark, leading to systemic desaturation and cyanosis. So, the best description is the reversal of the left-to-right shunt caused by pulmonary vascular remodeling increasing pulmonary resistance. The other ideas—pulmonary hypertension without shunt reversal, spontaneous closure of the defect, or isolated pulmonary hypertension without shunt changes—don’t capture the defining feature of Eisenmenger.

Eisenmenger syndrome centers on a reversal of the flow across a congenital defect due to remodeling of the pulmonary vessels. When a large left-to-right shunt (such as from a VSD, PDA, or ASD) causes high blood flow and pressure in the lungs, the pulmonary vessels progressively hypertrophy and narrow (medial hypertrophy and intimal hyperplasia). This raises pulmonary vascular resistance until it exceeds systemic vascular resistance, flipping the shunt to right-to-left. That reversal is the hallmark, leading to systemic desaturation and cyanosis.

So, the best description is the reversal of the left-to-right shunt caused by pulmonary vascular remodeling increasing pulmonary resistance. The other ideas—pulmonary hypertension without shunt reversal, spontaneous closure of the defect, or isolated pulmonary hypertension without shunt changes—don’t capture the defining feature of Eisenmenger.