Challenges in Pulmonary Hypertension: Controversies in Treating the Tip of the Iceberg. A Joint National Institutes of Health Clinical Center and Pulmonary Hypertension Association Symposium Report

[...]in a retrospective cohort study of treatment-naive incident cases of chronic lung disease-associated severe precapillary PH, as defined above, PAH-specific therapy did not result in significant improvements in New York Heart Association functional class or 6MWD (87). [...]data from the COMPERA registry did not demonstrate any significant difference in the proportion of patients who improved their 6MWD or functional class with PAHspecific therapy in patients with ILD-PH who fulfilled the definition for severe PH versus those who did not (88). Whether a subset of patients with ILDPH will benefit from PAH-specific therapy remains an untested hypothesis. [...]at this time, optimizing oxygen delivery, treating the underlying lung condition as well as associated comorbidities (e.g., left heart disease, volume overload), and referral of eligible patients for lung transplant remain the only valid recommendations for patients with ILD-PH (3). [...]a systematic, noninvasive strategy integrating results from highresolution computed tomography, DLCO, arterial blood gas analysis, and 6MWD testing with pulse oximetry is necessary to identify PVOD as the cause of precapillary PH (107). Similar to patients clinically diagnosed with PVOD, patients with PAH with biallelic EIF2AK4 mutations (n = 9) did not improve their functional status with pulmonary vasodilators and had a shortened survival. [...]genetic testing for biallelic EIF2AK4 mutations should be considered in younger patients clinically diagnosed with IPAH but with a low diffusing capacity to prompt consideration of early referral for lung transplantation.