The National Institutes of Health has awarded Cleveland Clinic researcher Eileen Hsich, M.D., $2.8 million over four years to evaluate disparities in survival among heart failure patients before and after heart transplantation and to create tools that would optimize outcomes.
“We believe that to improve care for those with heart failure awaiting transplant, we must better understand how differences among patients affect the timing of transplants and survival. With this knowledge, we can create innovative models that can help physicians decide the best time for individual patients to be transplanted,” said Dr. Hsich. “The findings from these research projects will hopefully lay the groundwork for a dynamic and improved way to allocate hearts in the future.”
Heart failure affects 6.5 million Americans, and many need advanced care such as circulatory support devices or transplant. However, due to a shortage of organs, numerous people die each year waiting for a heart. Currently, about 4,000 patients are waiting for heart transplants, and in 2017, surgeons performed about 3,200 heart transplants.
The grant will be used for three research projects:
- Using the national Scientific Registry of Transplant Recipients (SRTR), researchers will identify key risk factors and quantify how interactions among them directly affect differences in survival before and after transplant using machine learning statistical methods. Some of these disparities include sex, race, type of heart disease, socioeconomic status, mechanical circulatory support and region.
- Using data from Cleveland Clinic and four other institutions, the research team will develop the first method to dynamically update risk of death on the national heart transplant waiting list so that clinicians caring for these patients are alerted to the patient’s changing condition. The research team will include variables currently not collected by SRTR for patients awaiting transplantation, such as tests that show markers of severity of disease and those reflecting the failure of other organs (liver function tests). They will also provide a more complete picture of a patient’s overall health and ability to function. The other institutions participating are Northwestern University, University of Pennsylvania, University of Pittsburgh and Duke University Medical Center.
- Using data from the first two projects, Dr. Hsich and her co-principle investigator, Hermant Ishwaran, Ph.D., director of Statistical Methodology at the University of Miami Health System, will develop statistical models that simultaneously estimate risk of waiting list mortality, time to transplantation, and death after transplantation, as affected by patient characteristics and their health while on the waiting list. This will allow physicians to better estimate the best timing for transplant as a patient’s condition changes. Similar risk prediction models have been successfully developed and used in lung, liver and kidney transplantation. The existing heart allocation system is based on a tiered system that prioritizes patients by risk of death on the waiting list mainly by need for certain devices or certain medications, but does not take into account how their condition changes, the likelihood that a patient will get transplanted, or the risk of death after transplant.
This work with will build upon other studies by Dr. Hsich investigating disparities in heart transplant patients. Her previous research has identified differences in heart transplant waiting list survival based on type of heart disease. Other research that she has led confirmed that despite shorter times on the list, women have higher mortality compared to men waiting urgently for heart transplants.