Prognostic Value of Hemodynamic vs Big Endothelin Measurements During Long-term IV Therapy in Advanced Heart Failure Patients*

Study objective: To compare hemodynamics and plasma big endothelin levels in patients awaiting heart transplantation who are receiving continuous IV therapy, and to establish their respective potency for predicting future cardiac events. Design: A randomized, prospective trial of ambulatory continuous treatment with IV prostaglandin E1 (PGE1) vs dobutamine. A subanalysis was conducted of all patients who completed 4 weeks of follow-up in regard to treatment effects on hemodynamics and big endothelin plasma levels. Patients: Thirty-two listed heart transplant candidates who were refractory to oral treatment, 21 patients who were receiving PGE1, and 11 patients receiving dobutamine. Measurements and results: Hemodynamics and plasma big endothelin levels were measured at baseline and after 4 weeks. The cardiac index increased significantly (PGE1 group, 1.7 6 0.4 vs 2.5 6 0.6 L/min/m 2 ; dobutamine group, 1.8 6 0.3 vs 2.3 6 0.6 L/min/m 2 ;p < 0.05), whereas the systemic vascular resistance index (SVRI) decreased significantly only in the PGE1 group (3,352 6 954 vs 2,178 6 519 dyne z s z cm 25 /m 2 ;p < 0.05). The plasma big endothelin level decreased significantly (PGE1 group, 7.6 6 3.1 vs 4.7 6 2.6 fmol/mL; dobutamine group, 6.5 6 3.7 vs 5.0 6 2.6 fmol/mL; p < 0.01 for the time effect). Plasma big endothelin ( b5 0.393; x 2 5 10.8; p 5 0.001) and SVRI ( b5 0.003; x 2 5 6.9; p < 0.01), both measured after 4 weeks of continuous treatment, were the only independent predictors of future outcome. Conclusion: Continuous treatment over 4 weeks with either PGE1 or dobutamine in patients awaiting heart transplantation yields an improved hemodynamic state accompanied by a reduction of increased big endothelin levels. Plasma big endothelin measured after 4 weeks of continuous therapy provides prognostic information about future outcome. (CHEST 2000; 117:1713‐1719)