OBJECTIVES: Recent technological breakthroughs in the design of reliable systems for long term non-pulsatile mechanical heart support offer the possibility to study the effect of continuous blood flow in the vascular system. Generally, it is assumed that the absence of physiological pulsatile flow leads to prothrombogenic and proatherogenic changes. We investigated the change in the circulating endothelial microparticle concentration as a marker of endothelial damage in patients implanted with a continuous-flow left ventricle assist device (LVAD). METHODS: Endothelial microparticles were measured in 8 males (mean age 54.1±11.5 years) with terminal heart failure before and 3 months after implantation of an LVAD. The group consisted of 3 patients with dilated cardiomyopathy, 3 patients with ischemic cardiomyopathy, 1 patient with both conditions and 1 patient with congenital valvular disease. The concentration of endothelial microparticles was determined by ELISA Zymutest MP activity test. RESULTS: We did not observe a significant change in the concentration of circulating endothelial microparticles measured before and 3 months after implantation (p=0.669). High inter-individual variability in response to implantation was found. However, no association between a change in endothelial microparticle concentration and heart failure aetiology or a significant clinical complication attributed to LVAD implantation was observed. CONCLUSION: Results from this preliminary pilot study do not indicate that LVADs contribute to short-term vascular damage as defined by an increase in circulating endothelial microparticles.

Institute of Clinical and Experimental Medicine Prague Czech Republic