SAFETY AND EFFICACY OF BETA-BLOCKADE IN PATIENTS WITH CHRONIC CONGESTIVE-HEART-FAILURE AWAITING TRANSPLANTATION

Background: Donor availability remains a limiting factor for heart tra nsplantation, while transplant waiting time entails significant morbid ity and mortality. This study was designed to assess the efficacy and safety of long-term beta blockade as optimization of therapy in patien ts with severe congestive heart failure already receiving digoxin, diu retics, and converting enzyme inhibitors awaiting transplantation. Met hods: The beta-1 antagonist metoprolol was given to 19 patients with m oderate to severe congestive heart failure. Hemodynamic, clinical, and neurohormonal measurements were obtained before drug therapy and afte r 3 months of treatment. Patients initially received 6.25 mg of metopr olol orally twice daily which was increased to a target dose of 50 mg twice daily over several weeks. Results: Metoprolol produced significa nt clinical, exercise, and hemodynamic benefits. Long-term therapy was associated with improvements in New York Heart Association class, eje ction fraction, 6-minute walk, and peak maximal oxygen consumption. Th ere were significant decreases in heart rate, pulmonary arterial systo lic pressure, and left ventricular filling pressure with significant i ncreases in stroke volume index and stroke work index. Four patients w ere removed from the transplant list after improving to New York Heart Association I. Only one patient required hospitalization during the f irst 6 months of therapy. There were no deaths caused by progressive h eart failure; however, one patient died suddenly. Conclusions: Beta bl ockade with metoprolol can be safely administered to patients awaiting heart transplantation producing clinical, exercise, and hemodynamic i mprovements. Thus, beta blockade may prove to be a safe and cost-effec tive bridge to transplantation.