Congenital Heart Disease-Associated Pulmonary Hypertension

most commonly occurring with moderate to large unrepaired systemic-to-pulmonary shunt lesions. ? Given similar histopathologic changes, clinical presentation, and response to targeted therapy, PAH associated with CHD is classified with other forms of World Symposium on Pulmonary Hypertension group 1 PAH. ? Prognosis varies depending on the type and size of the congenital heart defect, the timing of the development of PAH, and the response to treatment. ? Pulmonary vascular disease associated with univentricular heart (both before and after total cavopulmonary connection) forms a unique and challenging subgroup of APAH-CHD, with different diagnostic and prognostic criteria and therapeutic indications. Although PAH associated with CHD has common histopathologic and pathobiologic findings as other disorders clustered together under WHO group 1 pulmonary hypertension, this group is very heterogeneous in terms of anatomic, physiologic, and clinical features, as well as outcomes. With improved survival of patients with CHD, the number of patients with CHD and PAH seen in adult CHD clinics is increasing. This subgroup of patients has unique clinical features and potential complications compared with patients with other forms of WHO group 1 PAH. Targeted PAH therapies have clear short-term benefits in these patients, and their use in patients with borderline hemodynamics may pave the way for a combined medical-surgical approach to management in borderline cases in the future. However, further large studies are required to evaluate the long term outcome using these strategies. A subpopulation of APAH-CHD that is growing rapidly includes those patients with complex single ventricle anatomy, and large multicenter studies are required to better understand the Fontan physiology and evaluate potential benefits of targeted PAH therapies in these patients.

Automated summary

Pulmonary arterial hypertension associated with congenital heart defects, particularly with systemic-to-pulmonary shunt lesions, is classified with other forms of PAH according to World Symposium on Pulmonary Hypertension group 1 classification. Prognosis varies based on the type and size of the heart defect, development of PAH, and response to treatment. Univentricular heart-related pulmonary vascular disease forms a challenging subgroup, which requires different diagnostic and prognostic criteria.