A new study from the University of Pennsylvania School of Medicine shows that physicians might need to change the way they monitor patients with heart valve issues after undergoing certain treatments.

The study found that patients who receive a transcatheter aortic valve replacement (TAVR) to treat low flow aortic stenosis, but don’t see improvements in their aortic blood flow after the procedure, have a 60 percent higher chance of death in the following year than patients who do see an improvement in aortic blood flow.  

But physicians don’t always look at blood flow to determine a patient’s post-TAVR recovery, the study points out. Some look at other indicators, such as pressure gradient and valve area. Those measurements don’t give as reliable a reading on one-year mortality rates as measuring blood flow, according to the study.

Head of Penn Medicine’s Interventional Cardiology Program Howard C. Herrmann, MD, said in a statement, "While low flow is more challenging to monitor, this measurement can better inform the patient's risk of mortality and in turn lead to better treatment."

The study, published in the Journal of the American Medical Association—Cardiology, looked at nearly 1,000 patients between April 2014 and January 2016. It measured the patients' blood flow in their narrowed artery before and after the TAVR procedure, along with other markers. The patients who had especially low blood flow before the procedure continued to have a harder time after the procedure. Twenty-six percent of patients with “severe” low flow died within the first year.

The researchers pointed out that accurately monitoring which patients were having the most restricted flow could help physicians devise more detailed treatment plans for post-TAVR low flow aortic stenosis, which could lead to decreased mortality rates after the procedure.