Pulmonary hypertension (PH) had been recognized as an intractable disease with poor prognosis. In Japan, oral pulmonary vasodilators have been approved one after another since 2005, resulting in drastic improvement of treatment outcomes. Our knowledge of mechanisms responsible for development and progression of PH has been increased, based on clinical classification and treatment algorithm proposed at 5th World Symposium held in Nice. However, underlying mechanisms of PH are heterogeneous, and some patients are still classified as “PH with unclear multifactorial mechanisms (group 5)”. It is necessary to proceed with personalized medicine on the basis of pathobiology to achieve maximum treatment efficacy.
The “multiple-hits theory” is proposed as an underlying mechanism for development of PH, but the genetic, molecular, pathological and environmental mechanisms responsible for the development of PH have not been fully elucidated. In this symposium, factors critical to the process of pulmonary vascular remodeling as well as potential future treatment targets are discussed through presentation of case series with PH.