Effects of Continuous Flow Left Ventricular Assist Device Support on Microvascular Endothelial Function

Abstract

The effects of continuous flow left ventricular assist device (CF-LVAD) support on microvascular endothelial function in New York Heart Association (NYHA) class IV heart failure (HF) patients are currently unknown. Microvascular endothelial function was assessed by beat-to-beat plethysmographic measurement of finger arterial pulse wave signal changes for 5 min following reactive hyperemia. A group of seven NYHA class IV HF patients was evaluated before CF-LVAD placement (HF), and a second group of six NYHA class IV HF patients was evaluated 1-4 months following CF-LVAD placement (CF-LVAD). Additionally, a third group of seven age-matched healthy subjects served as controls (control). There was no significant (P > 0.05) difference among the three groups in age, weight, or height. Systolic blood pressure (BP) was significantly higher in the control group (120 ± 2 mmHg) as compared to that in the HF (97 ± 8 mmHg, P = 0.005) and CF-LVAD (106 ± 4 mmHg, P = 0.003) groups. Diastolic BP was significantly lower in the HF group (57 ± 5 mmHg) as compared to that in the control (71 ± 2 mmHg, P = 0.012) and CF-LVAD (80 ± 7 mmHg, P = 0.008) groups. The reactive hyperemic index (RHI), a measure of endothelial function, was significantly higher in the control group (2.373 ± 0.274) than in both the HF (1.543 ± 0.173, P = 0.013) and CF-LVAD (1.355 ± 0.163, P = 0.004) groups; however, there was no significant (P = 0.223) difference in RHI between the HF and CF-LVAD groups. The results of the present study demonstrate that while 1-4 months of CF-LVAD support do not negatively affect microvascular endothelial function, 1-4 months of CF-LVAD support do not significantly improve vascular function in resistance vessels.

Further Peripheral Vascular Dysfunction in Heart Failure Patients With a Continuous-Flow Left Ventricular Assist Device

“…Again, there appears to only be one other study, to date, that has evaluated the effects of continuous-flow LVAD support on microvascular function. In that study, Lou et al (38) reported that 1–4 months of LVAD support did not negatively affect microvascular function, as measured by the reactive hyperemia index, compared to a group of HFrEF patients that were awaiting LVAD implantation. These findings support the results of the current study, however, given the increased incidence of LVAD implantation as a destination therapy and the potential for vascular stiffening to occur with long-term ventricular support (39), further studies are necessary to better examine blood flow distribution and the consequences in the microcirculation with LVAD use.…”

Sexual function in patients supported with left ventricular assist device and with heart transplant

“…18,19 Therefore, it is possible that factors contributing to sexual dysfunction with HF are not completely reversed during the LVAD support. Performance dysfunction (erectile dysfunction or vaginal dryness) was the most prevalent.…”

Identification of Differentially Expressed Transcripts and Pathways in Blood One Week and Six Months Following Implant of Left Ventricular Assist Devices

“…Substantial progress has been made in understanding molecular and genetic changes following VAD[17], but much remains unknown. The impact of altered blood flow from CF-VAD on endothelial function is unclear[52], and improved understanding is likely to accelerate efforts to mitigate hematologic complications. Finally, studying patients whose heart failure is briskly and substantially reversed with mechanical circulatory support may offer insights into the pathophysiology of heart failure beyond the findings in this specific population.…”