Pulmonary Vasoreactivity and Phenotypes in Pulmonary Arterial Hypertension Associated to Connective Tissue Diseases.

Background: Pulmonary arterial hypertension (PAH) is a fatal complication in patients with connective tissue disease (CTD).

Objective: The objective of the study was to study the prognostic value of the acute pulmonary vasoreactivity test with inhaled iloprost and its association with clinical deterioration in a tertiary care academic medical center.

Methods: We conducted a prospective study of patients with CTD and the diagnosis of PAH established by right heart catheterization. Patients were classified into classic responders, partial responders, and non-responders. The association of the pulmonary response and clinical deterioration was analyzed.

Results: We enrolled 25 patients (mean age of 47 ± 13.4 years); 88% were female. The most frequent rheumatologic diagnosis was systemic lupus erythematosus, in 16 (64%) patients. Seventy-two percent of patients were classified as non-responders, and 28% were partial responders. Patients with a partial response had lower right atrial pressure values (5.1 ± 3.1 vs. 8.5 ± 3.2, p = 0.01) and greater systolic pulmonary arterial pressure (87.6 ± 8.1 vs. 72.4 ± 16.2, p = 0.02), compared with non-responders. Non-responders had a tendency for a shorter time to clinical deterioration than partial responders (17.8 vs. 41.1 months, p = 0.052).

Conclusions: Patients with a partial response to the acute pulmonary vasodilator test with inhaled iloprost had a longer clinical deterioration-free period than non-responders.