Heart valve surgery linked to transient declines in cognitive function
Heart valve surgery patients, including those who undergo aortic and mitral interventions, are at risk of temporary cognitive decline for up to six months after their procedure, according to a study published in the Journal of the American Geriatrics Society this week.
First author Mark A. Oldham, MD, and coauthors wrote in the journal that despite an aging global population and high demand for heart surgeries, research hasn’t focused on outcomes of valvular procedures. But 156,000 heart valve surgeries were performed in the U.S. in 2014, and the majority were triggered by aortic stenosis—a condition that disproportionately affects seniors.
“This is of pressing concern for geriatricians because individuals aged 65 and older represent the vast majority of aortic valve surgery candidates, and because the number of older adults with calcific aortic stenosis is projected to double by 2050 in the United States and Europe,” Oldham, an assistant professor of psychiatry at the University of Rochester Medical Center, and colleagues wrote.
“Furthermore, older age is among the strongest predictors of cognitive decline after CABG surgery. Therefore, understanding cognitive trajectory after surgery for valvular heart disease (VHD) is of critical public health significance for older adults.”
Oldham and his team rifled through the MEDLINE, EMBASE and PsychINFO databases and retrospectively studied 12 articles on the topic. They found subjects of valve surgery all showed moderate early cognitive decline at baseline, but those results differed by surgery type. In all cases, cognitive function was relatively restored within six months.
Patients who underwent aortic valve surgery, who were on average 11 years older than seniors undergoing mitral valve surgery, had a steeper rate of early cognitive decline than their peers. Aortic patients saw a Becker mean gain effect size (ES) of -0.68—significantly lower than mitral patients’ ES of -0.12. Still, both groups showed similar rates of decline two to six months postoperatively, with ES values of -.0.27 and -0.20, respectively, for aortic and mitral patients.
“The primary strength of our report is its comprehensive, quantitative approach,” Oldham et al. wrote. “Becker’s mean gain effect size allowed us to define change in global cognition and compare studies that assess disparate cognitive domains, but we are unable to comment on specific cognitive domains because these studies used various tests from different neuropsychological batteries.”
The authors also noted it’s important to be cautious of results when effect sizes are so small, like they were in this case. They said work in the coming years should focus on refining risk stratification and prevention strategies in the surgical population, as well as look into the long-term cognitive outcomes associated with valve surgery.
“Future studies to define risk factors for cognitive decline after surgery for VHD should focus on person-related factors as the most likely meaningful predictors of cognitive outcomes,” Oldham and colleagues said. “Also, with increasing availability of TAVR, comparative data on determinants of cognitive trajectory between TAVR and VHD surgery would be highly relevant for choice of procedure for individuals with VHD, especially older adults.”
After graduating from Indiana University-Bloomington with a bachelor’s in journalism, Anicka joined TriMed’s Chicago team in 2017 covering cardiology. Close to her heart is long-form journalism, Pilot G-2 pens, dark chocolate and her dog Harper Lee.