Stress doppler echocardiography in connective tissue disease patients without overt pulmonary arterial hypertension

Background Pulmonary arterial hypertension(PAH) is a common complication of connective tissue disease(CTD) and confers a worse prognosis. Stress doppler echocardiography(SDE) can detect early pulmonary vasculopathy and assess right heart function in patients with pulmonary arterial hypertension. In this study, the SDE was applied to analyze the degree of pulmonary vascular lesion and the function of right heart in CTD patients without overt PAH. Methods CTD patients without overt PAH were divided into exercised-induced pulmonary hypertension(EIPH) group and non-EIPH group depending on whether tricuspid regurgitation(TR) exceeded 3.1 m/s during exercise and assessed by echocardiography at rest and during exercise. The data of right ventricular function and the slope of the incremental of the mean pulmonary artery pressure and cardiac output(ΔmPAP/ΔCO) were analyzed. Results Forty-seven CTD patients without overt PAH(35 female, mean age 40.3±12.0 years) were enrolled and divided into EIPH group(n=21) and non-EIPH group(n=26). Patients with systemic sclerosis(SSc) were more likely to have EIPH(47.6% vs. 28.6%, P<0.05) than those with systemic lupus erythematosus(SLE). Patients in EIPH group had a higher value of ΔmPAP/ΔCO than that of the non-EIPH group(4.5±3.1 vs. 2.2±1.3, P<0.05). SSc was more prevalent in CTD patients and the symptoms of dyspnea occurred more often in EIPH group(52.4%), indicating a pressure-flow mismatch induced by exercise. However, the cardiac function demonstrated by left ventricular ejection fraction(LVEF), tricuspid annular plane systolic excursion(TAPSE),DTI-Derived S’-wave velocity(S’) and right ventricular fractional area change(RVFAC), as well as functional reserve reflected by the changes of TAPSE, S’, RVFAC before and after exercise, did not differ significantly between the two groups. Conclusions Although right ventricular(RV) reserve function does not change much before and after exercise, patients in EIPH group have a higher value of ΔmPAP/ΔCO than that of the non-EIPH group and more likely to have symptoms during exercise. Thus, to assess the potential for pulmonary vascular disease, echocardiography should be performed at rest and during exercise.[S Chin J Cardiol 2019;20(1):31-36]