Vascular function in patients with advanced heart failure and continuous-flow or pulsatile ventricular assist devices

Area of Science:

• Cardiovascular Medicine
• Vascular Biology
• Heart Failure Research

Background:

• Advanced heart failure (HF) significantly increases morbidity and mortality.
• Mechanical circulatory support with ventricular assist devices (VADs) is an option for eligible patients.
• Vascular dysfunction is central to HF pathophysiology, but VAD impact is unclear.

Purpose of the Study:

• To investigate the effect of VAD implantation on endothelial vascular function in advanced heart failure.
• To compare macrovascular and microvascular function between VAD recipients and propensity-matched advanced HF patients.

Main Methods:

• Evaluated endothelial function using flow-mediated vasodilatation (FMD) for large arteries and flicker-light induced retinal vasodilatation (FID) for microcirculation.
• Compared 34 VAD patients (26 CF-LVAD, 8 bi-VAD) with 34 propensity-matched advanced HF patients.
• Assessed arterio-venous ratio (AVR) as an indicator of retinal vascular tone.

Main Results:

• VAD patients showed significantly improved FMD compared to advanced HF patients (7.2% vs. 5.0%, p=0.03).
• No significant difference in microvascular function (FIDart) was observed between groups (p=0.78).
• VAD recipients had a higher AVR (0.90 vs. 0.85, p=0.01), indicating altered retinal vessel diameters.

Conclusions:

• VAD implantation improves endothelial function in large arteries of advanced HF patients.
• Microvascular function is not significantly affected by VAD support.
• No differences in vascular function were found between continuous-flow LVAD and pulsatile bi-VAD.