Background:Recent studies have indicated that cardiac autonomic dysfunction is an early sign of cardiovascular impairment in patients with connective tissue disease (CTD). Previous studies have mainly focused on autonomic regulation during rest in this population. The cardiac autonomic responses to an acute physiological stress might provide additional information on the autonomic dysfunction, serving as a powerful predictor of cardiovascular disease and mortality in patients with CTD.Objectives:We aimed to use exercise stress echocardiography to detect early right heart dysfunction in patients with CTD and healthy controls.Methods:Treadmill exercise stress echocardiography was performed in 19 CTD patients (8 systemic sclerosis, 6 mixed CTD and 5 SLE) and 20 healthy volunteers. Parameters of right ventricular (RV) systolic function (RV fractional area change, Doppler tissue s’ velocity, and systolic strain and strain rate) and diastolic function (peak E and A velocity, Doppler tissue e’, a’ and early and late diastolic strain rate) were evaluated at baseline and after exercise, with the difference (Δ) being systolic and diastolic reserve. The immunoblotting assay was performed to detect the levels of rheumatoid factor (RF) and C-reactive protein (CRP) as well as autoantibodies such as, antinuclear antibody (ANA), anti-U1 ribonucleoproteins (U1RNP), anti-dsDNA, anti-Sm, anti-SSA, anti-SSB, anti-SCL-70 and RO-52. The correlation between these proteins and RV function was analyzed.Results:Both the patients with CTD and healthy controls had a normal range of BMI, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG). The average age of patients with CTD was 46.0 ± 10.4 years. At baseline, these patients presented no cardiovascular disease or pulmonary hypertension. No significant difference in the body weight, height, age, sex, blood pressure, RV and left ventricular (LV) function at rest between the two groups (allP>0.05). The parameters of RV systolic reserve decreased significantly in CTD group compared to those of the healthy controls (Δs’: 5.8±2.1 vs 8.3±2.5cm-1,P<0.01; ΔSr: 2.5±0.8 vs 2.8±0.7s-1,P<0.01). Consistently, RV diastolic reserve was significantly decreased in CTD patients compared to controls (Δe’: 2.8±1.5 vs 3.9±2.3cm-1,P<0.05; Δa’: 5.8±2.5 vs 10.9±6.3cm-1,P<0.05; ΔE-Sr: 0.8±0.2 vs 1.2±0.5s-1,P<0.05; ΔA-Sr: 0.9±0.3 vs 1.3±0.6s-1,P<0.05). To identify independent predictors of RV function in CTD patients, linear regression was conducted. This suggested that ANA, anti-U1RNP, anti-dsDNA, anti-Sm, anti-SSA, anti-SSB, anti-SCL-70 and RO-52 were not correlated with RV reserve (allP>0.05). A logistic regression analysis revealed that RF (P<0.05) and CRP (P<0.01) were independently associated with RV reserve in CTD patients in response to an acute physiological stress.Conclusion:Treadmill exercise echocardiography could detect right heart dysfunction early before diagnosed as cardiovascular diseases in patients with CTD. RV reserve after exercise might be a promising parameter to detect cardiovascular disease early in CTD patients.References:[1]Lazzerini PE, Capecchi PL, Laghi-Pasini F. Systemic inflammation and arrhythmic risk: lessons from rheumatoid arthritis.Eur Heart J. 2017;38(22):1717–1727.[2]Peçanha T, Rodrigues R, Pinto AJ, et al. Chronotropic Incompetence and Reduced Heart Rate Recovery in Rheumatoid Arthritis.J Clin Rheumatol. 2018;24(7):375–380.Disclosure of Interests:None declared