Seeing the invisible the imediments to timely diagnosis of pulmonary arterial hypertension

There appears to be evolutionary change in the landscape of PAH epidemiological, both in prevalent and incident cases, prognosis and outcomes from Centres of Excellence in PHT management. What is clear, is that there seems to be significant ‘expanding prevalence’ rates as one looks from the top to the bottom of the tertiary / quaternary care model, down to community / primary care for patients with PAH. Gaining a fundamental understanding of the true community burden of PAH /PHT may have significant impact on health resourcing requirements, mortality and indeed QoL outcomes for PHT / PAH patients. To date, no data exist describing the population perspective of community prevalence of PAH, and there are no comparative data denoting to what extent all-cause PHT may be present in the general population. Furthermore, not only do we have limited knowledge of the true rate of disease, we have very scarce information pertaining to the natural history for PAH. Of those patients who make it to a centre of PHT management, all reported registries to date describe significant delay in diagnosis. Do these delays impact on mortality? Is this apparent delay in diagnosis one of the reasons our incident and prevalence outcome data is heterogeneous? To date, no one has specifically looked at this delay to examine any common themes that may emerge and if the delay is associated with any factors or indeed has impact on mortality. In this thesis we sought to understand the prevalence of PAH in an Australia population and to determine, if any, what impact this may have on survival of Australians living with PHT in the Australian community setting? We will seek to identify possible themes in any delay and examine the journey through the Australian healthcare system for patients with PAH. we will initiate two unique screening programs for PAH associeted with SSc and CHD. After analysis and review, we will propose a multidisciplinary and integrated model of care for PAH in the Australian healthcare system. We have outlined, for the first time, the common presentation of community based PHT and the impact that has on mortality! PAH remains under recognised in general practice and community based specialty medicine. There remain a significant number of patients with PHT in Echocardiography labs that may benefit from further investigation to determine the cause of their PHT. Patients with idiopathic PAH in Australia appear to be delayed in gaining adequate diagnosis. It does appear possible to design and implement programs that promote earlier diagnosis of certain “at Risk” PHT populations. In our case, patients with SSc were identified earlier than via physician suspicion alone. We have undertaken the first step in quantifying the Australian Congenital Heart disease population, specifically those with acquired PAH. Undertaking a thesis on “seeing the invisible”, appears to have illuminated a number of critical issues for future research focus on understanding community presentations, the complexity and cost of screening, diagnosis and management of this relatively common, complex and multi faceted disease.