A New Tool for Timely Rescue of Heart Transplant Patients with Severe Primary Graft Dysfunction

Abstract

ADVANCEMENTS IN heart transplantation have come a long way since Barnard, Shumway, and other pioneers first performed the revolutionary procedure more than 50 years ago. 1 Progress in appropriate donor and recipient selection, organ protection, surgical and anesthetic techniques, and postoperative management have significantly reduced the initial mortality rates once seen with heart transplant. Indeed, the early years of 1968-to-1970 saw worldwide 1-year survival at 18% and 2-year survival at only 11%. 2 Today, 1-year survival of heart transplant patients is as high as 85%. 3 Despite the significant improvement in long-term survival, current-day heart transplant recipients remain at high risk for postoperative morbidity and mortality due to primary graft dysfunction (PGD). PGD occurs within the first 24 hours after transplant, and it results in single or biventricular dysfunction with low cardiac output and hypotension despite adequate filling pressures. 4 Unlike secondary graft dysfunction, there remains no identifiable cause. Although consensus statements exist on characterizing PGD, there remains variability on PGD diagnosis and definition from one center to another. This has ultimately contributed to a wide range in the reported incidence of PGD, from 2.3% to 28.2%. 5 Given that PGD is the leading cause of early mortality (fewer than 30-days) after heart transplantation, continued focus remains on predicting and preventing this devastating complication. Registry data demonstrates that 39% of deaths at 30 days are attributed to PGD, and this number has not significantly improved in recent years despite the advancements mentioned above. 6 Risk models for predicting PGD have been validated, and risk factors associated with this multifactorial disease have been identified. 7 Not surprisingly, risk factors are related to donor, procedural, and recipient characteristics. Also, not surprising is that many of these risk factors cannot be eliminated given the limited donor organ pool and the increasing number of end-stage heart failure patients. Therefore, more "marginal" donors are being accepted for older, higher-risk recipients. 7 Furthermore, identifying risk factors (not modifiable