Misclassification of Pulmonary Hypertension Due to Reliance on Pulmonary Capillary Wedge Pressure Rather Than Left Ventricular End-Diastolic Pressure

摘要

Background: Pulmonary arterial hypertension (PAH) is typically distinguished from pulmonarynvenous hypertension (PVH) by documenting a pulmonary capillary wedge pressure (PCWP) < 15nmm Hg. However, PCWP has uncertain utility in establishing PAH. We sought to determine thencalibration, discrimination, and diagnostic accuracy of PCWP, using simultaneously measured leftnventricular end-diastolic pressure (LVEDP) as the “gold standard.”nMethods: We examined hemodynamic data from the 11,523 unique patients undergoing simul-ntaneous right-heart and left-heart catheterization at a large academic center from 1998 to 2007.nResults: Among 4,320 patients (37.5%) with pulmonary hypertension (PH) [mean pulmonarynartery pressure, > 25 mm Hg], hemodynamic data were complete for 3,926 patients (90.9%). Ofnthese, 580 patients (14.8%) met the criteria for PAH with a PCWP < 15 mm Hg, but 310 of thesenpatients (53.5%) had an LVEDP > 15 mm Hg. Such discrepancies remained common amongnpatients with a pulmonary vascular resistance > 3 Wood units and those being catheterizednspecifically to evaluate PH. PCWP provided moderate discrimination between patients with highnvs normal LVEDP (area under the receiver operating characteristic curve, 0.84; 95% confidenceninterval, 0.81 to 0.86) but was poorly calibrated to LVEDP (Bland-Altman limits of agreement,nu0001 15.2 to 9.5 mm Hg; Hosmer-Lemeshow goodness-of-fit u00022nstatistic, 155.4; p < 0.0001).nConclusions: Roughly half of the patients presumed to have PAH based on PCWP may be foundnto have PVH based on LVEDP. Reliance on PCWP may result in the dangerous or cost-ineffectivenuse of pulmonary vasodilators for patients with left-heart disease. Furthermore, without assessingnLVEDP, investigators may include patients with left-heart disease in therapeutic trials of PAHndrugs, thereby limiting their ability to detect beneficial drug effects.