Systematical quantitative study of subclinical left ventricular myocardial dysfunction in patients with systemic lupus erythematosus by four-dimensional echocardiography

Abstract

Objective To visualize and quantitatively evaluate the left ventricular four-dimensional strain and torsion parameters in patients with systemic lupus erythematosus (SLE) by speckle tracing echocardiography to reveal subclinical left ventricular myocardial dysfunction. Methods Fifty-nine patients suffering from SLE without evidence of myocardial impairment at Sichuan Provincial People's Hospital from July 2017 to January 2018 were selected (SLE group), and 37 age and sex-matched healthy volunteers matched undergoing physical examination during the same period were selected as a healthy control group. All of the subjects underwent standard transthoracic echocardiography, 4D Auto LVQ, and TDI examinations. The cumulative left ventricular geometry data, such as left ventricular posterior wall end-diastolic thickness (LVPWT), left ventricular end-diastolic diameter (LVEDD), ventricular septal end-diastolic thickness (IVST), left ventricular end-diastolic volume (EDV), and end-systolic volume (ESV); left ventricular functional data, such as left ventricular ejection fraction (LVEF), stroke volume (SV), and left ventricular myocardial performance index (MPI); mean E/e and left ventricular global longitudinal strain (GLS), left ventricular global circumferential strain (GCS), left ventricular global radial strain (GRS), left ventricular global area strain (GAS), twist, and torsion were measured. The above parameters between the two groups were compared for difference by the independent-samples t-test. Results For parameters related to left ventricular geometry, the values of LVPWT and IVST in the SLE group were within the normal reference range, but were significantly higher than those of the healthy control group (t=5.816、5.336, P 0.05). LVEF was more than 60% in both groups, and there was no significant difference in LVEF, FS, or SV between the two groups (P>0.05). The left ventricular MPI and mean E/e in the SLE group were significantly higher than those of the healthy control group [MPI: 0.47±0.10 vs 0.38±0.07; mean E/e: 8.0±1.7 vs 6.9±0.9; t=4.352、4.009, P<0.05 for both). The values of GLS, GCS, GRS, and GAS were significantly lower in patients with SLE than in healthy controls [GLS: (-16.4±2.7)% vs (-20.6±2.1)%; GCS: (-15.0±2.8)% vs (-17.7±2.5)%; GAS: (-27.4±4.0)% vs (-32.5±2.9)%; GRS: (43.7±8.2)% vs (55.4±7.5)%; t=8.210、4.724、7.277、7.029, P<0.05 for all]. Conclusion 4D Auto LVQ combined with TDI can be used to systematically and quantitatively detect subclinical myocardial dysfunction in SLE patients, which may provide systematical visual evidence for early diagnosis and treatment evaluation of subclinical heart disease in SLE. Key words: Systemic lupus erythematosus; Four-dimensional echocardiography; Subclinical; Myocardial dysfunction