Layer‐specific strain and dyssynchrony index alteration in new-onset systemic lupus erythematosus patients without cardiac symptom
Abstract Background Layer-specific speckle-tracking echocardiography (STE) is a noninvasive approach assessing subclinical left ventricular (LV) dysfunction. We aimed to investigate: (I) layer‐specific strain and dyssynchrony index alteration; (II) disease parameters associated with layer-specific STE change; (III) effects of hydroxychloroquine (HCQ) therapy on layer-specific STE parameters in drug-naïve patients with new-onset systemic lupus erythematosus (SLE) without cardiac symptoms. Methods 35 drug-naïve patients with new-onset SLE and 25 age-and-sex-matched healthy controls were enrolled. All individuals received both conventional echocardiographic and two-dimensional STE assessment. Layer-specific global longitudinal strain (GLS), global circumferential strain (GCS) and peak systolic dispersion (PSD) were acquired in layer-specific STE. The effect of HCQ monotherapy on GLS parameters and PSD was assessed in 7 SLE patients with stable disease. Results All patients had normal left ventricular ejection fraction (LVEF). Conventional echocardiographic parameters were comparable between patients and controls. Decreased layer-specific GLS and elevated PSD were observed in SLE patients. In contrast, there’s no difference of layer-specific GCS at the basal level, papillary muscle level and apical level between patients and controls. More severely impaired GLS was observed in patients with higher disease activity, high-risk aPL profile or renal involvement. PSD increased in patients with higher disease activity or high-risk aPL profile. Correlational analysis showed that GLS at three layers and PSD correlated with high-sensitivity CRP (hsCRP) levels. PSD correlated with epicardial GLS, when treating hsCRP level, renal involvement, profile of aPL and disease activity as control variables. Multivariate regression showed hsCRP level and epicardial GLS are the predictors of layer-specific GLS impairment and elevated PSD, respectively. No change of GLS at three layers or PSD was observed in the first 6 months of HCQ treatment, compared with baseline. During the second 6 months of HCQ treatment, increase of endocardial GLS and whole layer GLS, and decrease of PSD were detected. There was no change of epicardial GLS during follow-up. Conclusion Drug-naïve patients with new-onset SLE, even having normal LVEF, are likely to have subclinical GLS impairment and LV dyssynchrony. SLE-related risk factors are associated with these dysfunctions. Continuous use of HCQ may provide beneficial effects to the silent cardiac impairment.