Aim: The prognosis of pulmonary hypertension (PH) in systemic sclerosis (SSC) and in systemic lupus erythematosus (SLE) is different. According to the guidelines, right heart catheterization (RHC) is necessary in pulmonary arterial hypertension (PAH) associated with connective tissue diseases (CTD). However, there is little supporting evidence. Therefore, we attempted to determine the necessity for RHC and the causes of differences in prognosis of PH by comparing SSC to SLE.
Methods: The inclusion criteria were all patients with SSC or SLE with exertional dyspnea. Echocardiography and carotid Doppler ultrasound were performed.
Results: Twenty-three patients with SSC and 23 with SLE participated in this study. There was no difference in the right ventricular systolic pressure (RVSP) between SSC and SLE (33.0 mmHg, range 25.3-41.7 mmHg vs. 32.4 mmHg, range 27.0-37.7 mmHg; P = 0.835). In multiple linear regression analysis, the ratio of peak tricuspid regurgitant velocity to right ventricular outflow tract time-velocity integral, which represents pulmonary vascular resistance (PVR), was correlated with RVSP in SSC (r(2) = 0.928, β = 0.362, P = 0.003), and the independent predictor of increased RVSP was the ratio of early diastolic transmitral filling velocity to early diastolic septal mitral annular velocity, which represents diastolic dysfunction in SLE (R(2) = 0.806, β = 0.803, P = 0.023).
Conclusions: PVR was an important cause of PH in SSC. Left ventricular dysfunction was an important cause of PH in SLE. Thus, these findings demonstrate the necessity for RHC and differences in prognosis of PH in CTD.
Keywords: disease etiology and pathogenesis; systemic lupus erythematous; systemic sclerosis.
© 2015 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.