You are invited by your consultant to study data recorded from right heart catheterization.
Which one of the following is true?
A. The transpulmonary gradient is the difference between mean pulmonary artery pressure (mPAP) and mean pulmonary wedge pressure (mPWP)Transpulmonary gradient (TPG) is given by mPAP – mPWP and is normally <12 mmHg. Pulmonary vascular resistance is given by TPG divided by CO. A PWP >15 mmHg indicates left atrial hypertension. A vasodilator challenge is performed with inhaled nitric oxide to identify the small subset of patients with pulmonary arterial hypertension who will benefit from long-term calcium-channel blockade. A portion of those with an initially positive response (dmPAP ≥10 mmHg to ≤40 mmHg with d/normal CO) will become refractory to vasodilator provocation (and therefore calcium-channel blockade) in the future.