Prediction of new onset of resting pulmonary arterial hypertension in systemic sclerosis.

Background: Early detection of pulmonary arterial hypertension (PH) is crucial in systemic scleroderma. However, predictors of new onset of resting PH during follow-up (FUPH) have been poorly explored.

Aim: To determine whether nailfold videocapillaroscopy (NVC) grade and exercise echocardiographic variables are predictors of FUPH.

Methods: We prospectively enrolled 40 patients with systemic sclerosis (age 54±13 years; 68% women). All patients underwent graded semisupine exercise echocardiography and NVC. Baseline resting PH and FUPH were defined as systolic pulmonary arterial pressure (sPAP)>35 mmHg, and exercise-induced PH (EIPH) as exercise sPAP>50 mmHg.

Results: Seventeen patients developed EIPH (43%). During follow-up (FU) (25±15 months), 11 patients without baseline PH developed FUPH (28%), all from the EIPH group. Patients with FUPH were significantly older (60±14 vs 50±12 years; P=0.04), had higher resting and exercise sPAP (30±4 vs 22±5 and 60±12 vs 40±11 mmHg, respectively; P<0.0001) and a higher exercise E/e' ratio (9.4±0.7 vs 5.8±0.4; P=0.0003) and presented more frequently NVC grade>2 (90% vs 35%; P=0.0009). After adjustment for age, resting sPAP, exercise sPAP and NVC grade>2 were associated with maximal resting sPAP during follow-up and FUPH (P<0.05). Patients with both EIPH and NVC grade>2 had a very high incidence of FUPH (82%), and both variables remained strongly associated with FUPH after adjustment for age (hazard ratio 11.6, 95% confidence interval 2.4-55.3; P=0.002).

Conclusion: Exercise echocardiography and NVC can identify a subgroup of patients with systemic sclerosis who are at risk of developing FUPH.