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Updated: Aug 7, 2025

Insertion, Maintenance, and Removal of the Percutaneous Dual Lumen Cannula Right Ventricular Assist Device
Published on: July 20, 2022
Outflow cannula alignment in continuous flow left ventricular devices is associated with stroke
Mahwash Kassi1, Tanushree Agrawal2, Jiaqiong Xu3
1Houston Methodist Hospital, Houston, TX, USA.
Insights
Left ventricular assist device (LVAD) cannula alignment impacts stroke risk. Specific angles and diameters are linked to higher stroke incidence, suggesting a need for optimized graft configurations.
Area of Science:
- Cardiology
- Medical Devices
- Neurology
Background:
- Stroke is a significant complication following left ventricular assist device (LVAD) implantation.
- Clinical data on the contribution of LVAD cannula alignment to stroke risk is limited.
Purpose of the Study:
- To investigate the association between left ventricular assist device (LVAD) cannula alignment and stroke occurrence.
- To identify specific anatomical configurations of LVAD grafts that may increase stroke risk.
Main Methods:
- Retrospective analysis of 78 patients who underwent LVAD implantation and cardiac CT scan.
- Evaluation of LVAD graft alignment using X-ray, echocardiography, and cardiac CT.
- Primary outcome assessed was stroke within one year of LVAD implantation.
Main Results:
- 15.4% of patients experienced a stroke within one year of LVAD implantation.
- Lower LVAD outflow cannula to aortic angle (<37.5°) and smaller outflow graft diameter (<1.5 cm) were significantly associated with higher stroke risk.
- In Heart Mate II device recipients, lower LVAD speed at CT scan correlated with increased stroke risk.
Conclusions:
- LVAD outflow cannula alignment and graft diameter are critical factors influencing stroke risk.
- Optimizing LVAD graft configuration may be a strategy to mitigate stroke complications.
- Further research is warranted to establish optimal outflow graft parameters for stroke prevention.
Abstract:
We sought to evaluate whether differences in left ventricular assist device (LVAD) canula alignment are associated with stroke. There is a paucity of clinical data on contribution of LVAD canulae alignment to strokes. We conducted a retrospective analysis of patients who underwent LVAD implantation at Houston Methodist hospital from 2011 to 2016 and included those who had undergone cardiac computed tomography (CT) with contrast. LVAD graft alignment using X-ray, echocardiography, and cardiac CT was evaluated. The primary outcome was stroke within 1 year of LVAD implantation. Of the 101 patients that underwent LVAD Implantation and cardiac CT scan during the study period, 78 met inclusion criteria. The primary outcome occurred in 12 (15.4%) patients with a median time to stroke of 77 days (interquartile range: 42-132 days). Of these, 10 patients had an ischemic and two had hemorrhagic strokes. The predominant device type was Heart Mate II (94.8%). Patients with LVAD outflow cannula to aortic angle lesser than 37.5° and those with outflow graft diameter of anastomosis less than 1.5 cm (assessed by cardiac CT) had significantly higher stroke risk (p < 0.001 and p = 0.01 respectively). In HMII patients, a lower LVAD speed at the time of CT scan was associated with stroke. Further studies are needed to identify optimal outflow graft configuration to mitigate stroke risk.
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