Cognition and Cerebral Infarction in Older Adults After Surgical Aortic Valve Replacement

Abstract

Background: Aortic valve replacement (AVR) for calcific aortic stenosis is associated with high rates of perioperative stroke and silent cerebral infarcts on diffusion-weighted magnetic resonance imaging (MRI), but cognitive outcomes in elderly AVR patients compared with individuals with cardiac disease who do not undergo surgery are uncertain.

Methods: One hundred ninety AVR patients (mean age 76 ± 6 years) and 198 non-surgical participants with cardiovascular disease (mean age 74 ± 6 years) completed comprehensive cognitive testing at baseline (preoperatively) and 4 to 6 weeks and 1 year postoperatively. Surgical participants also completed perioperative stroke evaluations, including postoperative brain MRI. Mixed model analyses and reliable change scores examined cognitive outcomes. Stroke outcomes were evaluated in participants with and without postoperative cognitive dysfunction.

Results: From reliable change scores, only 12.4% of the surgical group demonstrated postoperative cognitive dysfunction at 4 to 6 weeks and 7.5% at 1 year. Although the surgical group had statistically significantly lower scores in working memory/inhibition 4 to 6 weeks after surgery, the groups did not differ at 1 year. In surgical participants, postoperative cognitive dysfunction was associated with a greater number (p < 0.01) and larger total volume (p < 0.01) of acute cerebral infarcts on MRI.

Conclusions: In high-risk, aged participants undergoing surgical AVR for aortic stenosis, postoperative cognitive dysfunction was surprisingly limited and was resolved by 1 year in most. Postoperative cognitive dysfunction at 4 to 6 weeks was associated with more and larger acute cerebral infarcts.