Left ventricular assist device (LVAD) therapy is associated with substantial postimplantation morbidity and mortality, a study has confirmed. Readmissions after LVAD implantation are commonplace and often due to gastrointestinal bleeding, device malfunction and/or heart failure.
“Although LVAD has been the focus of significant research, most studies have looked at mortality,” said Atul Gupta, MBBS, clinical associate in the Department of Anesthesia at the University of Chicago Medicine. “On the other hand, not many studies have looked at readmission rates and the reasons for readmission, which was our primary focus.” Indeed, although LVAD placement rapidly has become an integral component in the treatment of advanced heart failure, the risk factors and outcomes associated with LVAD readmissions are poorly characterized.
Huge Database Employed
Dr. Gupta, along with senior authors Sajid S. Shahul, MD, and Mohammed Minhaj, MD, performed a retrospective cohort analysis using data from the 2013 Nationwide Readmissions Database, which provides discharge data on approximately 15 million hospital stays annually. The database has data from a geographically diverse cohort of 21 states, which accounts for 49.3% of all U.S. hospitalizations.
It was found that of the 35,580,347 weighted national discharges, 3,500 admissions were for primary LVAD implantation. The mean length of stay for an LVAD implantation was 37.3 days, while in-hospital mortality associated with device implantation was 12.9%.
“These mortality findings were confirmation of what is already known in the literature,” Dr. Gupta told Anesthesiology News. “But we were also trying to see if we could predict any particular risk factors that could predict readmission.”
As Dr. Gupta reported at the 2017 annual meeting of the Society of Cardiovascular Anesthesiologists (abstract SCA197), the mean 30-day readmission rate was 30.27% (n=923 readmissions). The mean length of stay for the first readmission was 9.8 days. The most common principal readmission diagnoses among nonsurvivors included intracerebral hemorrhage (9.8%), mesenteric ischemia (5.7%) and aortic valve dysfunction (5.5%).
One of the most common risk factors for readmission included peripheral vascular disease, Dr. Gupta revealed. “Interestingly, there were a few patients who underwent chemotherapy for lymphoma, had heart failure and then got an LVAD,” Dr. Gupta said. “Those patients also had a higher risk of readmission.”
Equally eye-opening were the factors that were not associated with readmissions, he continued. “We looked at other possible confounders like kidney and liver failure, and they weren’t associated with 30-day readmissions,” Dr. Gupta said. “That came as a bit of a surprise.”
Although Dr. Gupta acknowledged the research is subject to the classic limitations of retrospective research, he was hopeful that improved understanding may lead to a decrease in readmissions after LVAD placement. “Obviously this was a preliminary study, but as more databases come out, we hope to combine them and get more comprehensive results,” he added.
“Nevertheless, these findings are confirmation of what we already know, but on a much larger scale.”
Deborah E. Myers, MD, medical director of heart failure programs at the Texas Heart Institute, in Houston, agreed that the results were disappointingly predictable. “I didn’t think there was anything surprising here. As I always describe to my patients, when you get an LVAD, you’re trading one set of problems for another.”
Results such as these help illustrate how much room there is for improvement with LVADs. “I think what it portends is that the technology as it is now has to get better,” Dr. Myers said. “One thing that would really go a long way here is a transcutaneous power supply, which I believe would reduce the infection rate we see with these devices. Because one thing we know is that when these patients get infected, it tends to set off a cascade of bad things, including cerebral bleeds.”
Improved biocompatibility of the pump surfaces also would improve their long-term efficacy, she added. “I love LVAD technology,” she said, “but there are clearly some drawbacks to it.”