Objective: The goal of this study was to analyze the hemodynamic responses during vasoreactivity tests among candidates for heart transplantation who displayed severe pulmonary hypertension seeking to identify risk markers of nonresponse to the test.
Materials and methods: In this observational retrospective study we evaluated demographic, clinical, echocardiographic, and hemodynamic variables. The target hemodynamic goal in the vasoreactivity test was to achieve a transpulmonary gradient (TPG) <12 mm Hg and/or pulmonary vascular resistances (PVR) <2.5 Wood Units (WU).
Results: We analyzed medical records from 79 patients. Inotropes (dopamine or dobutamine) were used to treat 33 patients, nonselective vasodilators (nitroglycerin or sodium nitroprusside) were used in 22 patients, and prostacyclin (PC) was used in 24 patients. The study observed a significant decrease in pulmonary pressures, PVR, and TPG, with increased cardiac output (CO) compared with baseline hemodynamics in all groups. No significant differences were observed between agents except for an increase in CO, which was greater in the PC group. Also, 49.4% of patients were considered responders to the vasoreactivity test without significant differences between groups. Risk markers for absence of a response to the vasoreactivity test were a CO <2.5 L/min (odds ratio [OR] = 2.1; confidence interval [CI] 95%, 1.1-3.9; P = .035) and a PVR >6 WU (OR = 3.7; CI 95%, 1.8-7.6; P < .001) in the baseline hemodynamic study.
Conclusions: Inotropes, nonselective vasodilators, and prostacyclin produced effective vasodilator responses in the pulmonary vascular bed during the vasoreactivity test. The presence of a baseline high PVR or a low CO were predictors of nonresponse to the test.