To evaluate the value of treadmill exercise stress echocardiography (ESE) in the evaluation of right ventricular systolic function and contractile reserve in connective tissue disease (CTD) patients with normal resting pulmonary artery pressure.

Twenty-nine patients diagnosed with CTD without pulmonary arterial hypertension at rest in Sichuan Provincial People's Hospital from June 2018 to April 2019 (CTD group) and 28 healthy sex- and age-matched controls (control group) were enrolled. All the subjects underwent treadmill ESE. Parameters of right ventricular systolic function were measured at rest and immediately post-exercise: pulsed tissue Doppler systolic velocity (s'), peak longitudinal systolic strain (S) and systolic strain rate (S-Sr), right ventricular fractional area change (FAC), and tricuspid annular plane systolic excursion(TAPSE). Those parameters were compared between the two groups at rest and post-exercise.

Atrest, TAPSE, s', and S were significantly lower in the CTD group than in the control group (P=0.0000, 0.0001, 0.0384, P＜0.05). There was no significant difference in S-Sr and FAC between the two groups at rest(P＞0.05). s, S, S-Sr, FAC, and TAPSE were increased after exercise in both groups. All of those parameters were much lower in the CTD group than in the control group (P＜0.05). Right ventricular contraction reserve parameters including Δs', ΔS-Sr, ΔTAPSE, ΔFAC, and ΔS were much lower in the CTD group than in the control group (P＜0.05).

The right ventricular systolic function and contractile reserve after exercise are significantly impaired in patients with connective tissue disease without resting PAH. Exercise stress echocardiography is a simple, non-invasive method for assessing cardiac function, and it may be used for early diagnosis of impaired right ventricular systolic dysfunction and contractile reserve in CTD patients without resting PAH.