Photo Credit: Phira Phonruewiangphing

ECMO or ventilator use was the most significant predictor of mortality in patients undergoing lung transplant for idiopathic pulmonary arterial hypertension.

A prediction model incorporating factors associated with advanced pulmonary vascular disease effectively categorized 74% of lung transplant candidates with idiopathic pulmonary arterial hypertension (IPAH) as low- versus high-risk for 90-day mortality after transplant, according to a study published in Pulmonary Circulation.

“Identification of high-risk candidates may allow the application of more intensive strategies to mitigate complications that ultimately result in early mortality,” wrote corresponding author Reda E. Girgis, MD, and study coauthors.

The study included 693 adults with IPAH from the United Network for Organ Sharing database. The patients underwent lung transplantation between 2005 and 2021. Most patients were young to middle-aged women. Researchers examined factors associated with early mortality, specifically within 90 days of transplant.

Early mortality was high compared with other major diagnostic groups, with 10.2% of patients dying within 90 days of transplant. Causes included pulmonary/graft failure (28%), multiorgan failure (17%), infection (14%), cerebrovascular (13%), cardiovascular (11%), hemorrhage (8%), and other (9%).

The model identified several independent recipient factors that predicted early mortality. Odds ratios for 90-day mortality were:

• 3 for extracorporeal circulatory support and/or mechanical ventilation at transplant (CI, 1.4–5);
• 3 for total bilirubin above 2 mg/dL (CI, 1.4–7.2);
• 7 for ischemic time over 6 hours (CI, 1.01–2.86);
• 3 per 10 mmHg for higher pulmonary artery diastolic pressure (CI, 1.07–1.56); and
• 8 per 10% for reduced forced expiratory volume in the first second percent predicted (CI, 0.7–0.94).

“Our linear regression model was able to distinguish 25% of the cohort with a predicted 90-day mortality of [at least] 20% from 49% of the cohort with a mortality of 5% [or less], thereby identifying high-risk versus low-risk recipients,” the researchers wrote.

Among transplant recipients, 10% required extracorporeal membrane oxygenator (ECMO) and/or ventilator use before transplant. The need for this type of advanced life support was the strongest risk factor for early mortality.

“There has been increasing application of ECMO as a bridge to transplant in recent years for all indications,” Dr. Girgis and colleagues wrote. “While outcomes can be satisfactory relative to the dire hemodynamic derangement, early post-transplant mortality is considerably higher compared with non-supported recipients.”