One of the major causes of systemic sclerosis (SSc)-related death is pulmonary hypertension (PH), which develops in 12–15% of patients with SSc and accounts for 30–40% of deaths. Cardiac involvement is common in SSc and has been reported to range from 23 to 32%. Both pathophysiological processes can lead to PH. Consequently, monitoring of pulmonary arterial resistances (PVR) is essential in patients with SSc. Tricuspid regurgitation velocity (TRV) to right ventricular outflow tract time-velocity integral (VTI_RVOT) ratio by Doppler has been reported as a good tool to quantify PVR.

Explore the accuracy of TRV/VTI_RVOT ratio by Doppler to quantify PVR in patients with SSc.

Thirty-five consecutive patients with SSc referred for right heart catheterization (RHC) were retrospectively included. Doppler measures were compared to RHC measures. There were 20 (57%) female. The mean age was 65±12 years. Mean and systolic pulmonary arterial pressures were 31±8 and 53±15mmHg. There was a good correlation between TRV/VTI_RVOT ratio assessed by Doppler and PVR measured by RHC (R=0.743, P<0.001). The equation generated by this analysis was: PVR by Doppler=11.3×(TRV/TVIRVOT)+1.7. A cutoff value of 0.21 for TRV/TVIRVOT ratio provided the best sensitivity (86%) and specificity (86%) to determine PVR>3 Wood units (Fig. 1).

Our study suggests that transthoracic echocardiography using Doppler could be an interesting and non-invasive tool to estimate PVR in patients with SSc.