BACKGROUND Idiopathic pulmonary arterial hypertension (IPAH) is a devastating disease characterized by increased pulmonary vascular resistance, smooth muscle and endothelial cell proliferation, perivascular inflammatory infiltrates, and in situ thrombosis. Circulating intravascular ATP, ADP, AMP and adenosine activate purinergic cell signaling pathways and appear to induce many of the same path...

BACKGROUND Idiopathic pulmonary arterial hypertension (IPAH) is associated with proliferation of smooth muscle cells (SMCs) in small pulmonary arteries. There is no therapy that specifically inhibits SMC proliferation. Recent studies reported that prednisolone (PSL) inhibits the postangioplasty proliferation of SMCs in atherosclerotic arteries. In this study, we tested the hypothesis that PSL h...

Pulmonary arterial hypertension (PAH) is a rare disease often resulting in right-sided heart failure and premature death [1]. PAH is idiopathic (IPAH), heritable, or related to conditions such as connective tissue diseases (CTD) [2]. IPAH prognosis remains poor despite improved patient survival with current treatment options. Therefore, elucidating the pathophysiology of IPAH is important for t...

BACKGROUND/AIMS Idiopathic pulmonary arterial hypertension (IPAH) is an incurable disease with high mortality. Although most studies recommend anticoagulation treatment for IPAH, the benefits are uncertain, particularly in Korea, where it has not been studied. The purpose of this study was to evaluate survival outcomes of Korean patients with IPAH treated with warfarin. METHODS We performed a...

Idiopathic pulmonary arterial hypertension (IPAH) is a rare and progressive disease. Several processes are believed to lead to the fatal progressive pulmonary arterial narrowing seen in IPAH including vasoconstriction, cellular proliferation inflammation, vascular remodeling, abnormalities in the lung matrix, and in situ thrombosis. Nitric oxide (NO) produced by NO synthases (NOS) is a potent v...

To the Editor: We read with great interest the article in CHEST (June 2015) by Hautefort et al, 1 who demonstrated activity of the T helper 17 pathway in patients with idiopathic pulmonary arterial hypertension (IPAH). Th e authors further substantiated a potential role of an autoimmune pathogenesis in IPAH, a disease defi ned by the absence of known causes or associated conditions. “A fl avor ...

Idiopathic pulmonary arterial hypertension (IPAH) is a fatal disease characterised by elevated blood pressure in the pulmonary circulation. Initial vasoconstriction, proliferation of pulmonary arterial smooth muscle cells (PASMC) and increased deposition of extracellular matrix (ECM) contribute to pathological remodelling of pulmonary arterioles in IPAH. Glycosaminoglycans (GAGs), components of...

RATIONALE An increase in cytosolic free Ca(2+) concentration ([Ca(2+)](cyt)) in pulmonary arterial smooth muscle cells (PASMC) is a major trigger for pulmonary vasoconstriction and an important stimulus for PASMC proliferation and pulmonary vascular remodeling. The dihydropyridine Ca(2+) channel blockers, such as nifedipine, have been used for treatment of idiopathic pulmonary arterial hyperten...

I n this issue of the European Respiratory Journal, MATHAI et al. [1] (from Johns Hopkins University, Baltimore, MD, USA) report on their experience with the use of sildenafil, a phosphodiesterase-5 inhibitor, in patients with pulmonary arterial hypertension (PAH) who failed monotherapy with bosentan, an endothelin receptor antagonist. Within a 4-yr period, 82 patients with either idiopathic PA...

Alterations in extracellular matrix (ECM) have been implicated in the pathophysiology of pulmonary hypertension. Here, we have undertaken a compartment-specific study to elucidate the expression profile of collagens and their processing enzymes in donor and idiopathic pulmonary arterial hypertension (IPAH) pulmonary arteries. Predominant intimal, but also medial and perivascular, remodeling and...