Increased incidence of antiphospholipid antibodies in left ventricular assist system recipients

Background. Antiphospholipid antibodies are associated with thrombosis. Bec ause thromboembolic complications are often observed in recipients of a lef t ventricular assist system, we questioned if antiphospholipid antibodies w ere present in these patients. We report results from 10 patients who recei ved a Novacor left ventricular assist system. Methods. Serum samples were collected before left ventricular assist system placement and weekly thereafter until discharge after cardiac transplantat ion. Samples were tested for IgG, IgA, and IgM antiphosphatidylserine, anti cardiolipin, and antiphosphatidylethanolamine using an enzyme-linked immuno sorbent assay. Results. Development of phospholipid-binding plasma protein-dependent antip hospholipid antibodies was observed in 9 of the 10 patients. Before placeme nt of the assist system, 3 patients had IgG antiphospholipid antibodies, an d 9 were positive after placement. None had IgA antiphospholipid antibodies before placement, whereas 5 seroconverted for IgA after placement. One pat ient had IgM antiphospholipid antibodies before placement, and 1 additional patient became positive after placement. In patients with a preexisting an tibody, increased titers and additional specificities developed subsequent to placement. Conclusions. All but 1 patient showed development of phospholipid-binding p lasma protein-dependent antiphospholipid antibodies after left ventricular assist system placement. (C) 1999 by The Society of Thoracic Surgeons.