Aim: To obtain real-world evidence about the features and risk stratification of pulmonary arterial hypertension (PAH) with a left heart disease (LHD) phenotype (PAH-LHD). Methods and results: By reviewing the records of consecutive incident PAH patients at 7 tertiary centers from 2001 to 2021, we selected 286 subjects with all parameters needed to determine risk of death at baseline and at first follow-up with COMPERA and COMPERA 2.0 scores. Fifty seven (20%) had PAH-LHD according to the AMBITION definition. Compared with no-LHD ones, they were older, had higher BMI, more cardiovascular comorbidities, higher E/e' ratio and left atrial area, but lower BNP concentrations and better right ventricular function and pulmonary hemodynamics. Survival was comparable between PAH-LHD and no-LHD patients, although the former were less commonly treated with dual PAH therapy. Both COMPERA and COMPERA 2.0 discriminated all-cause mortality risk of PAH-LHD at follow-up, but not at baseline. Risk profile significantly improved during follow-up only when assessed by COMPERA 2.0. At multivariable analysis with low-risk status as reference, intermediate-high and high-risk, but not LHD phenotype, were associated with higher hazard of all-cause mortality. Results were comparable in secondary analyses including patients in the last 10 years and atrial fibrillation and echocardiographic abnormalities as additional criteria for PAH-LHD. Conclusions: In real life, PAH-LHD patients are frequent, have less severe disease and are less likely treated with PAH drug combinations than no-LHD. The COMPERA 2.0 model may be more appropriate to evaluate their mortality risk during follow-up and how it is modulated by therapy.
