American Board of Internal Medicine (ABIM) Certification Practice Exam

How is pulmonary hypertension related to left-sided heart disease classified?

1. Group 1

2. Group 2

3. Group 3

4. Group 4

The correct answer is: Group 2

Pulmonary hypertension secondary to left-sided heart disease is classified as Group 2. This classification is grounded in the etiology of pulmonary hypertension where it is understood to occur due to elevated pressures in the left heart leading to elevated pressures in the pulmonary circulation. Specifically, conditions such as left ventricular dysfunction or valvular heart disease can contribute to this type of pulmonary hypertension. In Group 2, there are measurable hemodynamic changes characterized by an elevated pulmonary artery pressure as a consequence of increased left atrial pressure. This classification also encompasses changes that arise from conditions like heart failure and mitral stenosis, where the left heart's inability to accommodate blood leads to congestion and consequently affects the pulmonary arteries. The other groups of pulmonary hypertension are designated based on different underlying mechanisms: Group 1 is for pulmonary arterial hypertension due to factors intrinsic to the pulmonary vasculature, Group 3 pertains to pulmonary hypertension associated with lung diseases and/or hypoxia, while Group 4 involves pulmonary embolism-related conditions. Thus, the classification highlights the underlying cause of pulmonary hypertension, solidifying left-sided heart disease as a significant contributor to the development of Group 2 pulmonary hypertension.