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

Background: A significant proportion of patients with heart failure (HF) progress to an advanced stage, which is associated with a substantial increase in morbidity and mortality. These patients may be eligible for advanced treatment strategies such as mechanical circulatory support with ventricular assist devices (VAD). Vascular dysfunction is a hallmark of heart failure pathophysiology and prognosis. However, whether and to what degree the hemodynamic benefits of VADs influence vascular function remain unknown.

Methods and results: In this study, we evaluated endothelial vascular function with flow-mediated vasodilatation (FMD) and with flicker-light induced retinal vasodilatation (FID). 34 patients with a VAD (age 58 ± 10 years, 85% male, 74% ischemic heart disease, 26 continuous-flow (CF)-LVAD, and 8 pulsatile biventricular (bi)-VAD) were compared to 34 propensity-matched patients (mean age 62 ± 9 years, 68% male, 59% ischemic heart disease) with advanced HF (AdvHF). Endothelial function of larger arteries (FMD) was significantly better in patients after VAD implantation compared to matched AdvHF patients (7.2 ± 4.6% vs. 5.0 ± 3.2%, p = 0.03), whereas microvascular arteriolar function (FIDart) did not differ (0.99 ± 1.43% vs. 1.1 ± 1.7%, p = 0.78). The arterio-venous ratio (AVR) was higher in the VAD group (0.90 ± 0.06 vs 0.85 ± 0.09, p = 0.01), reflecting wider retinal arteriolar and narrower venular diameters. There was no difference in vascular function between patients with CF-LVAD and pulsatile Bi-VAD.

Conclusion: In patients with advanced heart failure, VAD implantation was associated with better endothelial function at the level of large arteries, but not in the microcirculation.