# Neurovascular consequences of non-pulsatile flow from left ventricular assist devices

> **NIH NIH R01** · COLUMBIA UNIVERSITY HEALTH SCIENCES · 2022 · $599,698

## Abstract

Project summary:
This project will be an observational study with the primary goal to examine the consequences of non-pulsatile
flow under continuous flow left ventricular assisted devices (CF-LVAD) on the cerebral circulation. The public
health burden from congestive heart failure (CHF) is substantial and few treatment options are available to those
patients at the end-stage. Unfortunately, cardiac transplantation is not widely available and many of these
patients rely on left ventricular assist devices for circulatory support. The newest generation devices are
designed for durability and therefore deliver non-pulsatile flow. Despite improvements in CHF mortality, CF-
LVAD is associated with multiple complications that are hypothesized to originate from the impact of non-pulsatile
flow on arterial endothelium, notably gastrointestinal bleeding, and poor gains in exercise tolerance. CF-LVAD
patients develop unusually high rates of ischemic stroke with hemorrhagic transformation (ISHT), one of the
leading causes of death in these patients. ISHT in the general population results from microcirculatory
dysfunction with disruption of the blood brain barrier (BBB) and cerebral endothelium. The impact of non-pulsatile
flow on the BBB and cerebral endothelium has not yet been studied in human CF-LVAD patients, in part due to
the lack of markers specific to the cerebral circulation. In aim 1a we will perform transcranial Doppler (TCD)
before and after CF-LVAD implantation to measure the breath holding index as a physiological marker of cerebral
autoregulation an important function of cerebral endothelium. In aim 1b we will examine the impact of non-
pulsatile flow on the blood retina barrier (anatomically similar to the BBB) with optical coherence tomography
angiography and retinal doppler. In aim 2 we will examine changes in cognition in CF-LVAD participants before
and after surgery and versus controls. The overall goals of this proposal will be to identify physiological and
functional changes which occur in the cerebral circulation under non-pulsatile flow which will allow for improved
risk stratification and tailored treatment approaches in the application of CF-LVAD in end-stage CHF.

## Key facts

- **NIH application ID:** 10367076
- **Project number:** 1R01NS121364-01A1
- **Recipient organization:** COLUMBIA UNIVERSITY HEALTH SCIENCES
- **Principal Investigator:** Joshua Zebadiah Willey
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $599,698
- **Award type:** 1
- **Project period:** 2022-01-01 → 2026-12-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10367076

## Citation

> US National Institutes of Health, RePORTER application 10367076, Neurovascular consequences of non-pulsatile flow from left ventricular assist devices (1R01NS121364-01A1). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10367076. Licensed CC0.

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