Right ventricular assessment matters for precision medicine.. reply to "Identifying parameters associated with response to switching from a PDE5i to riociguat in RESPITE"

We have read with great interest the article titled “Identifying parameters associated with response to switching from a PDE5i to riociguat in RESPITE”, reporting the results of a post hoc analysis performed in patients who completed RESPITE trial. This is an innovative approach in the setting of pulmonary arterial hypertension (PAH), opening the way for precision medicine. In this context, the REVEAL risk score (RRS) and NT-proBNP and growth/differentiation factor 15 (GDF-15), both indicative of right ventricular (RV) adaptation to increased afterload and RV remodelling, were identified as potential predictors of response in PAH patients switching from PDE5-i to riociguat. Interestingly, responders had lower biomarkers' levels and lower RRS than non-responders, suggestive of a less advanced RV remodelling. This finding, in line with the most recent evidence, highlights the need to integrate imaging-derived RV metrics into widely accepted risk scores, adding important information on RV function to indirect functional parameters, such as New York Heart Association functional class, six-min walk distance, eGFR and DLCO.