Abstract

Right ventricular (RV) adaptation to pressure overload is a major prognostic factor in patients with pulmonary arterial hypertension (PAH). The objectives were first to define the relation between RV adaptation and load using allometric modeling, then to compare the prognostic value of different indices of load adaptability in PAH. Both a derivation (n?=?85) and a validation cohort (n?=?200) were included. Load adaptability was assessed using 3 approaches: (1) surrogates of ventriculo-arterial coupling (e.g., RV area change/end-systolic area), (2) simple ratio of function and load (e.g., tricuspid annular plane systolic excursion/right ventricular systolic pressure), and (3) indices assessing the proportionality of adaptation using allometric pressure-function or size modeling. Proportional hazard modeling was used to compare the hazard ratio for the outcome of death or lung transplantation. The mean age of the derivation cohort was 44?±?11 years, with 80% female and 74% in New York Heart Association class III or IV. Mean pulmonary vascular resistance index (PVRI) was 24?±?11 with a wide distribution (1.6 to 57.5 WU/m2). Allometric relations were observed between PVRI and RV fractional area change (R2?=?0.53, p?

View details for DOI 10.1016/j.amjcard.2017.05.053