Pulmonary Hypertension Mnemonic for Effective Learning

An echocardiogram is the best initial diagnostic test for pulmonary hypertension. It can help detect right ventricular hypertrophy or dilation and can estimate pulmonary artery pressures.

Right heart catheterization (RHC) is the best confirmatory test for pulmonary hypertension. This involves a wire introduced from a peripheral vein and guided to the pulmonary artery after which a balloon is inflated at the tip that helps measure the pressure.

A mean pulmonary artery pressure (mPAP) above 20 mmHg at rest is diagnostic of pulmonary hypertesion as mentioned in the proceedings of the 6^th World Symposium on Pulmonary Hypertension. Normal mean pulmonary artery pressure is 10–14 mm Hg.

90% of patients with pulmonary arterial hypertension have an abnormal chest X-ray. Findings include enlarged right atrium, elevated cardiac apex (right heart enlargement sign), enlarged pulmonary arteries, "pruning" of peripheral pulmonary vessels, and an enlarged pulmonary trunk.

Treating the underlying cause of pulmonary hypertesion will help alleviate symptoms and might bring down pulmonary artery pressures. The classification of PH is discussed in a separate Picmonic.

Patients who respond well to vasodilators after an initial vasoreactivity test are often administered calcium channel blockers first.

Endothelin receptor antagonists work by blocking the endothelin-1 receptor. This action inhibits the vasoconstricting effects of endothelin-1. Bosentan, macitentan, and ambrisentan are examples of these drugs.

Prostacyclin (PGI₂) acts as a potent vasodilator on pulmonary and systemic arterial vascular beds, inhibits proliferation of vascular smooth muscle cells, and inhibits platelet aggregation. Epoprostenol and iloprost are prostacyclin analogs that are used for pulmonary arterial hypertension.

Phosphodiesterase type 5 (PDE-5) inhibitors work by inhibiting PDE-5 which normally degrades cGMP. This result in an increasing amount of cGMP thus prolonging the vasodilatory effects of nitric oxide (NO). Sildenafil and tadalafil are well known PDE-5 inhibitors.