Objectives: The continuous IV administration of prostacyclin improves pulmonary hemodynamics and prognosis in patients with primary pulmonary hypertension. We investigated whether the administration of prostacyclin therapy to patients before they undergo pulmonary thromboendarterectomy ameliorates pulmonary hypertension in patients with the most severe form of chronic thromboembolic pulmonary hypertension (CTEPH).
Methods: Of the 33 patients with CTEPH who were candidates for pulmonary thromboendarterectomy, 12 patients with severe pulmonary hypertension (pulmonary vascular resistance, > 1,200 dyne. s. cm(-5)) received IV prostacyclin prior to undergoing pulmonary thromboendarterectomy. Right heart catheterization and plasma brain natriuretic peptide (BNP) measurements were repeated at baseline, immediately before surgery, and 1 month after surgery.
Results: During a mean (+/- SEM) follow-up period of 46 +/- 12 days, the IV administration of prostacyclin resulted in a 28% decrease in pulmonary vascular resistance (1,510 +/- 53 to 1,088 +/- 58 dyne. s. cm(-5); p < 0.001) before surgery. Prostacyclin therapy markedly decreased plasma BNP level (547 +/- 112 to 188 +/- 30 pg/mL; p < 0.01), suggesting improvement in right heart failure. Pulmonary thromboendarterectomy caused a further reduction of pulmonary vascular resistance (302 +/- 47 dyne. s. cm(-5)) and plasma BNP levels (60 +/- 11 pg/mL) compared to each preoperative value (p < 0.05). Operative mortality rates were relatively low (8.3%) in patients with the most severe form of CTEPH.
Conclusion: The IV administration of prostacyclin caused beneficial hemodynamic effects in patients with severe CTEPH and may serve as pretreatment for patients undergoing pulmonary thromboendarterectomy.