Pulmonary arterial capacitance

Pulmonary arterial capacitance is an important predictor of mortality in heart failure with a preserved ejection fraction.

Al-Naamani et al. JACC: Heart Failure 2015;3(6):467-74.

Several definitions are explained in the introduction of this article.

Pulmonary hypertension secondary left heart disease is defined as mean PAP > 25 mmHg and mean PAWP > 15 mmHg.

Transpulmonary gradient > 12 mmHg is considered "disproportionate" increase in mean PAP relative to mean PAWP.

These two groups (disproportionate vs. proportionate increase in mPAP) may be better discriminated by diastolic pressure gradient > or = 7 mmHg vs. < 7 mmHg (ref:  Vachiery JL et al. Pulmonary hypertension due to left heart disease. JACC 2013 Dec;62(25 Suppl):D100-8).