The Incidence, Risk Factors, and Outcomes of Hyperlactatemia after Heart Transplantation.

Hyperlactatemia (HL) is associated with tissue hypoperfusion during cardiac surgery, which results in postoperative morbidity and mortality among patients undergoing cardiopulmonary bypass surgery. The aim of this study was to determine the incidence, risk factors, and outcome of HL after heart transplantation (HTx) in one of the largest Japanese single-center cohorts. We retrospectively studied the lactate levels in 49 patients who underwent HTx at the University of Tokyo Hospital from August 1, 2010 to November 30, 2015. All of the patients were over 20 years of age. Arterial blood samples were analyzed during the operation and until 24 hours after surgery. Twenty-nine patients (59.2%) had HL after intensive-care unit admission. At 24 hours after surgery, the lactate levels of all patients had recovered to the normal range. A multivariate analysis showed that the total ischemic time of the donor heart (odds ratio [OR], 1.0176; 95% confidence interval [CI], 1.0004-1.0375; P = 0.0444) and the duration of preoperative left ventricular assist device (LVAD) support (OR, 0.9977; 95% CI, 0.9952-0.9997; P = 0.0218) were risk factors for HL. Pulmonary complications were noted in 24.1% of the patients with high lactate values but in none of the patients without HL (P = 0.0182); however, there were no cases of hospital death, and the length of hospital stay did not differ to a statistically significant degree between HL groups (P = 0.719). Although HL after HTx was common, it appeared to be transient and benign. Donor heart ischemia and the duration of preoperative LVAD support were associated with HL after transplantation.