Antiphospholipid antibodies and coronary atherosclerosis: the antiphospholipid syndrome patients

Abstract

Background: In recent years it became apparent that mortality in patients with generalized autoimmune diseases like Antiphospholipid Syndrome (APS) and/or Systemic Lupus Erythematosus (SLE) is mainly due to severe cardiovascular complications. Conventional risk factors for coronary artery disease do not explain this increased risk. Suggested non-coventional factors include, among others, the presence of Antiphospholipid antibodies (aPL). Their elevated levels have been associated with arterial and microvascular thrombosis. Aims: To evaluate possible influence of aPL on myocardial ischaemia assessed by Single-Photon Emission Computerized Tomography (SPECT) and coronary atherosclerosis assessed by Multidetector Computerized Tomography (MDCT) in APS patients. Methods: SPECT (Tc 99m sestamibi) and MDCT-based coronary calcium scoring were performed in consecutive APS patients (12 females, 4 males, aged 28-62, mean 47,3) without clinical signs of heart disease. Anticardiolipin (aCL) and anti-beta2 Glycoprotein I (abeta2GPI) antibodies (IgG and IgM class) were measured by ELISA and Lupus Anticoagulant (LA) according to ISTH guidelines. Results: SPECT revealed myocardial perfusion defects in 12 (75%) patients: in 3 (19%) exercise-induced, and in 9 (56%) persistent. MDCT revealed coronary calcifications in 5 (31%) patients. The number of plaques ranged from 1 to 11 (median 2), volume 3-201,7 mm3 (median 7), calcium scores 1,3-202,6 (median 5,7). In patients with perfusion defects or coronary calcifications (n=12), as compared to patients without these pathologies (n=4) the levels of IgG aCL and/or IgG abeta2GPI antibodies were significantly higher and LA present more often (IgG aCL: 63,25±23,1 vs. 19,22±8,8, p=0,05; IgG abeta2GPI: 44,05±21,3 vs. 11,25±5,3, p=0.05; LA: 10/12 (83%) vs. 2/4 (50%), respectively). No such association was seen for IgM-class antibodies. Conclusions: In many symptom-free, relatively young APS patients SPECT shows myocardial perfusion defects and, in one third of them, coronary calcifications. These well-known cardiovascular risk markers were associated with the presence of LA and higher levels of aCL and abeta2GPI antibodies. In such patients advanced search for cardiovascular risk factors and proper preventive measures are warranted.