Prevalence and clinical significance of antiphospholipid antibodies in heart valve disease: a case-control study.

The purposes of this study were (1) to assess the prevalence of antiphospholipid (aPL) antibodies in patients with non-specific heart valve disease referred for valve replacement and (2) to determine whether the presence of aPL antibodies carries a risk for thrombotic events during a postoperative follow-up in a prospective cohort. The sera of 89 consecutive patients and 80 matched control subjects were tested for antibodies to cardiolipin (immunoglobulin G and immunoglobulin M) and for lupus anticoagulant. The prevalence of aPL antibodies was significantly higher in patients (19 [21%] of 89) than in control subjects (7 [9%] of 80) (p < 0.05). Patients were divided into two subgroups according to the presence (subgroup A) or the absence (subgroup B) of aPL antibodies. No significant difference in age or sex ratio was observed between the two subgroups. A history of arterial thrombosis was more frequent in subgroup A (8 [42%] of 19) than in subgroup B (8 [11%] of 70) (p < 0.01). No significant difference with respect to the occurrence of thrombotic events was observed during a median follow-up period of 8.7 months. Thus a high prevalence of aPL antibodies was found in patients referred for heart valve replacement compared with matched control subjects. No increased risk has been demonstrated in the patients with aPL antibodies.