Because liver transplants are among the surgeries at the highest risk to cause cardiac problems, researchers at Northwestern Medicine in Chicago have developed an app that can predict a liver transplant patient’s one-year risk of dying or being hospitalized due to a heart attack or other cardiac event.

During a liver transplant, changes in blood volume and adrenaline can affect heart function. With the app, physicians can get in front of detrimental cardiac events and keep patients healthier and alive for longer.

"Knowing the patient's risk is critical to help prevent the frequent cardiac complications that accompany liver transplant surgery and to determine which patients are likely to survive the transplant," said Lisa VanWagner, MD, an assistant professor of medicine and preventive medicine at Northwestern University Feinberg School of Medicine and a Northwestern Medicine physician.

Called the Cardiovascular Risk in Orthotopic Liver Transplantation, the app can be accessed online or as downloadable app for a smartphone from the iTunes or Google Play stores. The full paper on the app will publish in Hepatology on July 13.

The paper is based off a large cardiovascular risk-in-liver-transplant cohort study that included 10 years of data from liver transplant recipients. Results showed that patients who’ve been hospitalized for a cardiac event within 90 days of their liver transplant are at twice the risk of dying within one year.

The new app can be used for adults aged 18 to 75 with liver disease who are being considered for a liver transplant. To get the most accurate result, physicians collect patient information like age, sex, race, employment status and education level. Additionally, they collect their history with cancer, diabetes, heart failure, atrial fibrillation and pulmonary hypertension.

"Identifying persons who are at highest risk may mean restricting transplantation so that we maximize the benefit of scarce donor organs to persons who have a lower risk of a cardiac event and are more likely to survive the stress of a liver transplant," VanWagner said.

Currently physicians use several tools to determine a patient's cardiac risk when receiving a liver transplant, but the researchers who made the app argue that their method is more accurate.

There are more than 6,500 liver transplant procedures completed every year in the U.S., and more than 14,000 people are waiting for one. About one-third of recipients will experience a cardiovascular complication in the year after a transplant.