Left ventricular size and function in patients with systemic lupus erythematosus associate with lupus anticoagulant: An echocardiographic follow-up study

Background: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with increased risk of cardiac dysfunction. The pathophysiological mechanisms are poorly understood, and prognostic markers are warranted.

Purpose: We aimed to identify SLE-characteristics associated with measures of cardiac size and function during a five-year follow-up.

Methods: We included 108 patients with SLE: 90% females, mean age 46 ± 13 years, median disease duration 14 (range 7-21) years. We performed blood sampling for potential biomarkers as well as a standard echocardiography at baseline and at a 5-year follow-up. To investigate associations with baseline and prospective 5-year changes in echocardiographic parameters, we performed multivariate regression analyses of SLE-related baseline variables (clinical disease activity, lupus nephritis, chronic kidney disease, anti-cardiolipin and/or anti-beta-2 glycoprotein I antibodies, and lupus anticoagulant (LAC)) and adjusted for traditional risk factors.

Results: During follow-up, diastolic function regressed in two out of five echocardiographic measures (E/A ratio 1.4 ± 0.5 vs. 1.3 ± 0.5, p = 0.002; tricuspid regurgitation peak velocity 2.0 ± 0.6 vs. 2.2 ± 0.4 mmHg, p < 0.001). Left ventricular (LV) end-diastolic volume index increased (43.7 ± 13.9 vs. 52.5 ± 15.7 mL/m², p < 0.001). Left and right ventricular systolic function remained stationary. LAC was associated with inferior diastolic function: lower E/A ratio (p = 0.04) and higher E/e' ratio at baseline (p = 0.04) and increased left ventricular atrial volume index during follow-up (p = 0.01). LAC was further associated with LV dilatation during follow-up (p = 0.01).

Conclusion: Presence of LAC was associated with measures of diastolic function as well as progressive LV dilatation during the 5-year follow-up. Thus, LAC might be a predictor of cardiac dysfunction in SLE patients. LAC is known to have implications for the microvascular circulation, but the clinical significance of the present findings is yet to be elucidated.