HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Ranjit John Lyle Joyce Permission Requests Google Scholar Articles by John, R. Articles by Hebbel, R. PubMed Articles by John, R. Articles by Hebbel, R. Related Collections Mechanical Circulatory Assistance

---

Original Articles: Adult Cardiac

Activation of Endothelial and Coagulation Systems in Left Ventricular Assist Device Recipients

^a Division of Cardiothoracic Surgery, Department of Surgery, University of Minnesota, Minneapolis, Minnesota
^b Division of Hematology, University of Minnesota, Minneapolis, Minnesota

Accepted for publication June 25, 2009.

^_* Address correspondence to Dr John, Division of Cardiothoracic Surgery, University of Minnesota, 420 Delaware St SE, MMC 207, Minneapolis, MN 55455 (Email: johnx008{at}umn.edu).

Background: The paucity of organ donors has necessitated redirecting research toward finding alternative means to a heart transplant, such as left ventricular assist devices (LVADs) that will serve not merely as bridge-to-transplant but also as destination therapy. To better understand hemorrhagic and thromboembolic complications that currently limit the use of such devices, we studied the endothelial and coagulation system changes in LVAD recipients with time.

Methods: We studied these markers of endothelial dysfunction: circulating endothelial cells and expression of E-selectin, vascular cell adhesion molecule, intercellular adhesion molecule, and tissue factor on circulating endothelial cells, thrombin generation (prothrombin fragments 1,2 and thrombin/antithrombin), and fibrinolysis (D-dimer). Our study group consisted of 21 LVAD recipients (on day 0 and on postoperative days 1, 7, 30, 90, and 180) and 7 control patients undergoing non-LVAD cardiac surgery.

Results: Baseline values of intercellular adhesion molecule, E-selectin, tissue factor, thrombin/antithrombin, and D-dimer were significantly higher in LVAD recipients than the normal range. Markers of thrombin generation (thrombin/antithrombin and prothrombin fragments 1,2) and fibrinolysis (D-dimer) peaked postoperatively and declined to baseline levels or below by 3 months. But the expression of inducible endothelial markers (intercellular adhesion molecule, E-selectin, tissue factor) on circulating endothelial cells increased postoperatively, then decreased but remained elevated above preoperative levels for up to 6 months. In our control patients, baseline levels of intercellular adhesion molecule, E-selectin, tissue factor, D-dimer, and thrombin/antithrombin were lower and decreased significantly by day 7, as compared with LVAD recipients (p < 0.05).

Conclusions: Left ventricular assist device recipients experienced significant baseline activation of endothelial and coagulation systems, further accentuated in the early postoperative period. Left ventricular assist device recipients also had prolonged activation of the endothelial and coagulation systems, suggesting activation of the extrinsic (tissue factor) pathway of thrombosis mediated by sustained endothelial dysfunction in these patients. Further studies are needed to determine the clinical influence of such changes in LVAD recipients.