Cerebrovascular Accidents on Impella 5.5: Prevalence, Location, Outcomes

The Impella 5.5 is increasingly used as temporary mechanical circulatory support for cardiogenic shock and advanced heart failure, often for intermediate-term support. While neurologic complications are recognized, data describing the incidence, laterality, and outcomes of cerebrovascular accidents (CVAs) with Impella 5.5, particularly with axillary implantation, remain limited. We evaluated the incidence, timing, location, and consequences of CVAs occurring during Impella 5.5 support or the same hospitalization following device removal.

We performed a retrospective review of consecutive adult patients supported with Impella 5.5 at a single tertiary academic center between January 2022 and August 2025. Demographics, implantation approach (axillary vs central), duration of support, stroke type and laterality, and in-hospital mortality were collected. CVAs were identified clinically and confirmed by neuroimaging.

Among 164 patients (mean age 61.2 ± 11.7 years; mean LVEF 21.1 ± 9.4%), in-hospital mortality was 29.3%. Most devices were implanted via the axillary artery (79.3%), with the remainder placed centrally during surgery. CVAs occurred in 24 patients (14.6%), including 21 ischemic events (12.8%). Patients with and without CVAs were similar in age and LVEF; however, mortality was significantly higher in those with CVAs (50.0% vs 25.7%). The mean Impella support duration was 22.4 ± 30.9 days overall, longer for axillary than for central implants. Mean time from implantation to CVA was 17.4 ± 24.0 days. Among patients with right axillary Impella placement, all ischemic CVAs (100%) occurred ipsilateral to the device, with bilateral involvement in two cases. Central implants showed no consistent stroke laterality.

Ischemic CVAs occurred in over 12% of patients supported with Impella 5.5 and were associated with a twofold increase in mortality. The consistent ipsilateral occurrence of ischemic strokes with axillary Impella placement suggests a potential device-related mechanism as Impella 5.5 use expands for longer-duration support, targeted strategies to reduce cerebrovascular risk, and device design refinements are urgently needed.