What Makes New Ischemic Lesions Symptomatic after Aortic Valve Replacement?

Area of Science:

• Neurology
• Cardiothoracic Surgery
• Radiology

Background:

• Acute cerebral infarctions are frequently observed on diffusion-weighted magnetic resonance imaging (MRI) post-cardiothoracic surgery.
• Most of these infarcts are clinically silent, necessitating identification of factors linked to symptomatic events.

Purpose of the Study:

• To identify clinical, demographic, surgical, and imaging features associated with symptomatic stroke in elderly patients undergoing surgical aortic valve replacement (AVR).

Main Methods:

• Prospective recruitment of 196 patients over 65 undergoing AVR for calcific stenosis.
• Neurological evaluations and postoperative diffusion-weighted imaging (DWI) MRI were performed.
• Univariate and multivariable analyses were conducted on patients with new DWI lesions to determine factors associated with clinical stroke symptoms.

Main Results:

• Of 129 patients with postoperative MRI, 61% had DWI lesions; 21.5% of these experienced symptomatic strokes.
• Multivariable analysis indicated that increased age, longer cardiopulmonary bypass duration, and greater pre-existing lesion burden on fluid-attenuated inversion recovery (FLAIR) were associated with symptomatic neurological events.
• No specific lesion location was identified as a determinant of symptomatic lesions in the analyzed subgroup.

Conclusions:

• New DWI lesions are a common finding after AVR, with the majority being asymptomatic.
• Factors increasing the likelihood of symptomatic strokes include longer bypass durations, advanced age, and a higher burden of pre-existing brain lesions.