With significant therapeutic advances in the field of pulmonary arterial hypertension, the need to identify clinically relevant treatment goals that correlate with long-term outcome has emerged as 1 of the most critical tasks. Current goals include achieving modified New York Heart Association functional class I or II, 6-min walk distance >380 m, normalization of right ventricular size and function on echocardiograph, a decreasing or normalization of B-type natriuretic peptide (BNP), and hemodynamics with right atrial pressure <8 mm Hg and cardiac index >2.5 mg/kg/min(2). However, to more effectively prognosticate in the current era of complex treatments, it is becoming clear that the "bar" needs to be set higher, with more robust and clearer delineations aimed at parameters that correlate with long-term outcome; namely, exercise capacity and right heart function. Specifically, tests that accurately and noninvasively determine right ventricular function, such as cardiac magnetic resonance imaging and BNP/N-terminal pro-B-type natriuretic peptide, are emerging as promising indicators to serve as baseline predictors and treatment targets. Furthermore, studies focusing on outcomes have shown that no single test can reliably serve as a long-term prognostic marker and that composite treatment goals are more predictive of long-term outcome. It has been proposed that treatment goals be revised to include the following: modified New York Heart Association functional class I or II, 6-min walk distance ≥ 380 to 440 m, cardiopulmonary exercise test-measured peak oxygen consumption >15 ml/min/kg and ventilatory equivalent for carbon dioxide <45 l/min/l/min, BNP level toward "normal," echocardiograph and/or cardiac magnetic resonance imaging demonstrating normal/near-normal right ventricular size and function, and hemodynamics showing normalization of right ventricular function with right atrial pressure <8 mm Hg and cardiac index >2.5 to 3.0 l/min/m(2).
Keywords: 6-min walk distance; 6MWD; B-type natriuretic peptide; BNP; CHD-PAH; CI; CMR; EqCO(2); FC; HIV-PAH; IPAH; N-terminal pro–B-type natriuretic peptide; NIH; NT-proBNP; NYHA; National Institutes of Health; New York Heart Association; PAH; PAP; PH; PoPH; RAP; RV; RVEDVI; SLE-PAH; SSc-PAH; SvO(2); cardiac index; cardiac magnetic resonance; functional class; hemodynamics; idiopathic pulmonary arterial hypertension; mixed venous oxygenation; pulmonary arterial hypertension; pulmonary arterial hypertension related to congenital heart disease; pulmonary arterial hypertension related to human immunodeficiency virus infection; pulmonary arterial hypertension related to portal hypertension; pulmonary arterial hypertension related to scleroderma; pulmonary arterial hypertension related to systemic lupus erythematosus; pulmonary artery pressure; pulmonary hypertension; right atrial pressure; right ventricular; right ventricular end-diastolic volume index; right ventricular function; ventilatory equivalent for carbon dioxide.
Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.