Magnetic resonance imaging evaluation of cerebral embolization during percutaneous aortic valve implantation : comparison of transfemoral and trans-apical approaches using Edwards Sapiens valve

Objective: Cerebral embolization during trans-catheter aortic valve implantation (TAVI) has not been assessed clearly in the literature. Therefore, we compared the rate of cerebral embolisms with diffusion-weighted magnetic resonance imaging (DWI) in transfemoral (TF) and trans-apical (TA) approaches. Method: Eighty patients benefited from TAVI between January 2008 and June 2010. Out of these, 35 were included in the study. Twenty-one were TF (group 1) and 14 TA (group 2). During the same period, 285 patients benefited from a conventional aortic valve surgery (aortic valve replacement (AVR)). Thirteen of these were also analyzed and considered as the control group (group 3). We systematically performed a DWI the day before the procedure and 48h after. DWI studies were blindly analyzed by a neuroradiologist, and all patients had a clinical neurological assessment before and after the procedure, according the National Institutes of Health Stroke Scale (NIHSS). Results: Thirty-two patients in the TAVI group had new cerebral lesions: 19 in the TF group and 13 in the trans-apical group (p=NS). Mean number of embolic lesions per patient was 6.6 in group I and 6.0 in group II (p=NS). Mean volume of embolic lesions was 475.0mm(3) in group I and 2170.5mm(3) in group II (p=NS). In group III, one patient had one new cerebral lesion (p<0.05 vs TAVI) of 36.5mm(3) (p=NS vs TAVI). All patients were neurologically asymptomatic. Conclusions: The incidence of silent cerebral embolic lesions after TAVI is significantly higher compared with the standard surgical AVR. The number of emboli is similar in the TF and TA groups but the volume tended to be higher in the TA group. However, there is no clinical impact of those lesions.