Impact of β-blocker therapy on functional capacity criteria for heart transplant listing

Background: Peak exercise oxygen consumption is a widely used parameter to determine the need for transplant listing in patients with severe heart failure. Currently, beta-blocker therapy is known to benefit patients with severe heart failure, although it has minimal or no effects on peak exercise oxygen consumption. This raises the hypothesis that peak exercise oxygen consumption transplant-listing criteria are not valid for patients with heart failure who receive beta-blocker therapy. Methods: We compared outcomes in patients with chronic heart failure who underwent heart transplant evaluation with peak exercise oxygen consumption less than or equal to 14.0 ml/kg/min and who were treated with beta-blockers (n = 48) or who were not treated with beta-blockers (n = 55). Results: Outcomes were significantly better for patients treated with beta-blockers (combined end-points of death, transplantation as United Network for Organ Sharing [UNOS] Status I or 2, and ventricular assist device placement, p = 0.0001). The 1-year survival was 92% and 3-year survival was 71% in the patients treated with beta-blockers, and 69% and 48% in the patients not treated with beta-blockers (compared with UNOS transplant survival data of 92% 1-year and 77% 3-year survival rates). Conclusions: Patients with chronic heart failure and severe functional impairment who were treated with beta-blockers have significantly better outcomes compared with similarly functionally impaired patients who were not treated with beta-blockers, and these patients would not be expected to derive a survival benefit from transplantation. Thus, in patients treated with beta-blockers, the use of peak exercise oxygen consumption as a criterion to list for heart transplantation may no longer be valid. Alternatively, non-usage of beta-blockers may be a criterion to list for transplantation.