In the setting of moderate to severe pulmonary artery hypertension, orthotopic liver transplantation (OLT) may be complicated by pulmonary hemodynamic instability and cardiopulmonary mortality. We retrospectively studied the relationship between cardiopulmonary-related mortality and initial (untreated) pre-OLT pulmonary hemodynamics in 43 patients with portopulmonary hypertension who underwent attempted OLT. Thirty-six patients were reported in 18 peer-reviewed studies, and 7 patients underwent OLT at our institution since 1996. Transplantation procedure outcome, mean pulmonary artery pressure (MPAP), pulmonary vascular resistance (PVR), cardiac output, pulmonary capillary wedge pressure, and transpulmonary gradient (TPG) are summarized. Overall mortality was reported in 15 of 43 patients (35%). Fourteen of the 15 deaths (93%) were primarily related to cardiopulmonary dysfunction. Two deaths were intraoperative, 8 deaths occurred during the transplantation hospitalization, and 4 patients died of cardiopulmonary deterioration posthospitalization. In 4 patients, the transplantation procedure could not be successfully completed. Cardiopulmonary mortality was associated with greater pre-OLT MPAP (49 +/- 14 v 36 +/- 7 mm Hg; P <.005), PVR (441 +/- 173 v 261 +/- 156 dynes.s.cm(-5); P <.005), and TPG (37 +/- 13 v 22 +/- 10 mm Hg; P <.005). MPAP of 50 mm Hg or greater was associated with 100% cardiopulmonary mortality. In patients with an MPAP of 35 to less than 50 mm Hg and PVR of 250 dynes.s.cm(-5) or greater, the mortality rate was 50%. No mortality was reported in patients with a pre-OLT MPAP less than 35 mm Hg or TPG less than 15 mm Hg. Cardiopulmonary-related mortality in OLT patients with portopulmonary hypertension was frequent and associated with significantly increased pre-OLT MPAP, PVR, and TPG compared with survivors. Treated or untreated, we recommend intraoperative cancellation or advise against proceeding to OLT for an MPAP of 50 mm Hg or greater. Patients with an MPAP of 35 to less than 50 mm Hg and PVR of 250 dynes.s.cm(-5) or greater appear to be at high risk for cardiopulmonary-related mortality after OLT. A prospective study is needed to define optimal pretransplantation treatments and pulmonary hemodynamic criteria that minimize OLT mortality associated with portopulmonary hypertension.