PP.32.25

Abstract

Objective: Pulmonary hypertension (PH) is a group of chronic progressive diseases that have different etiology, but similar clinical presentation. Two conservative ways of treatment are available for such patients: calcium-channel blockers and specific PAH therapy. To define the right strategy right heart catheterization with acute vasodilator test (AVT) is performed. The aim of our study was to analyze the group of «true» responders, non-responders and patients in the «grey zone». Design and method: We analyzed 164 patients with verified diagnosis of PH who underwent right heart catheterization with AVT. Responders met the traditional criteria: reduction at 10 mm Hg. or more in mean pulmonary artery pressure with the aim of 40 mm Hg. and less with no evidence reduction in cardiac output. Non-responders did nit meet any of these criteria, while patients who are neither non-responders nor responders were defined as a “grey zone”. Results: All patients finally were divided into three groups: 34 responders, 28 non-responders and the largest group of 101 patients in a “grey zone”. Among the last group there was a big amount of patients with high reduction in pulmonary vascular resistance (PVR) (24,7 patients with reduction in PVR more than 300 dyn*sec/m2/cm5 with maximum of 1384 dyn*sec/m2/cm5), though they did not meet the criteria of cardiac output or/and mean pulmonary artery pressure. Among these 101 patients there were 26 with chronic thromboembolic pulmonary hypertension, 7 with PH associated with cardiac shunts, 12 with systemic connective tissue diseases and up to 48 of patients with Idiopathic pulmonary hypertension. The amount of patients with a high reduction in PVR (more than 300 dyn*sec/m2/cm5) is 26 with more than a half of patients with idiopathic pulmonary hypertension. Conclusions: In our national register we observed a huge amount of patients, who may present a great reduction in PVR in response to AVT - so called «grey zone». We need more research to specify the strategy for these patients.