Catecholamine support at the initiation of epoprostenol therapy in pulmonary arterial hypertension

Rationale: Epoprostenol is a first-line therapy for patients with pulmonary arterial hypertension (PAH) in World Health Organization functional class IV who often have low cardiac output and hypotension. However, initiation of epoprostenol can cause hemodynamic collapse in these vulnerable patients. Inotropic agent support may prevent the hemodynamic instability caused by initiation of epoprostenol; however, a protocol for supportive therapy has not been established.

Objectives: To assess the reliability and prognostic effects of dobutamine and dopamine support at the initiation of epoprostenol therapy in patients with PAH.

Methods: We initiated epoprostenol therapy in 71 patients with PAH. Hemodynamics at the initiation of epoprostenol were measured by right heart catheterization. We initiated dobutamine when a patient's mixed venous oxygen saturation was less than 60% or cardiac index was less than 2.0 L/min/m(2) or when right ventricular failure was clinically suspected. We initiated dopamine when a patient's systolic blood pressure was less than 90 mm Hg or urine volume was less than 20 ml/h.

Measurements and main results: At the initiation of epoprostenol, dobutamine and/or dopamine were required to support 46 patients according to protocol. Eight patients died during the hospitalization and one patient received a living-donor lobar lung transplant after the initiation of epoprostenol therapy. Neither inotropic agent was an independent risk factor for short-term mortality (dobutamine: hazard ratio, 1.63; 95% confidence interval, 0.33-8.11; dopamine: hazard ratio, 0.22; 95% confidence interval, 0.03-1.70). Sixty-two patients were discharged for home infusion of epoprostenol. Transplant-free survival rates at 5 years were 80.0% for patients who did not require inotropic support at the start of epoprostenol and 76.6% for patients with who did require dopamine and/or dobutamine support (P = 0.45).

Conclusions: Temporary use of dobutamine and dopamine appears to be safe for hemodynamic support at the initiation of epoprostenol therapy for selected patients with PAH with low cardiac output and hypotension. The protocol presented here requires validation at other centers.