Brain Injury After Transcatheter Replacement of Bicuspid Versus Tricuspid Aortic Valves

An increasing number of bicuspid aortic valve (BAV) patients are undergoing transcatheter aortic valve replacement (TAVR), but the risk of brain injury in diffusion-weighted magnetic resonance imaging (DW-MRI) is currently unknown.

This study sought to evaluate the risk of brain injury in BAV patients following TAVR.

A total of 204 consecutive severe aortic stenosis patients who underwent TAVR were enrolled. A total of 83 (40.7%) patients were BAV patients, and the other 121 patients were tricuspid aortic valve (TAV) patients. All patients received DW-MRI at baseline, and after TAVR.

Median ages (76 years [interquartile range (IQR): 71 to 81 years] vs. 79 years [IQR: 74 to 83 years]; p = 0.004) and Society of Thoracic Surgeons scores (4.87 [IQR: 3.72 to 8.54] vs. 6.38 [IQR: 3.96 to 9.50]; p = 0.044) of the BAV and TAV patients were significantly different, while the overt stroke rates (2.4% vs. 1.7%; p = 0.704) were comparable between the 2 groups. BAV patients were associated with higher number of new lesions (4.0 [IQR: 1.0 to 8.0] vs. 2.0 [IQR: 1.0 to 5.0]; p = 0.008), total lesion volume (290 mm³ [IQR: 70 to 930 mm³] vs. 140 mm³ [IQR: 35 to 480 mm³]; p = 0.008), and the volume per lesion (70.0 mm³ [IQR: 45.0 to 115.0 mm³] vs. 57.5 mm³ [IQR: 24.5 to 93.0 mm³]; p = 0.037) in DW-MRI. Moreover, the proportion of patients with lesions larger than 1 cm³ (28.6% vs. 10.9%; p = 0.005) was higher in BAV patients than in TAV patients.

BAV patients may encounter more severe brain injuries not only due to greater number of lesions, but also due to larger lesion size in the early phase after TAVR. (Transcatheter Aortic Valve Replacement Single Center Registry in Chinese Population [TORCH]; NCT02803294).