Parameters of acute vasoreactivity testing after balloon pulmonary angioplasty in patients with chronic thromboembolic pulmonary hypertension

Abstract

Aim.To study the effect of balloon pulmonary angioplasty (BPA) on the changes of pulmonary artery pressure, cardiac output and structural parameters of pulmonary arteries after acute vasoreactivity testing (AVT) in inoperable patients with chronic thromboembolic pulmonary hypertension (CTEPH). Materials and methods.The prospective study included 22 patients with inoperable CTEPH. 11 patients underwent intravascular ultrasound (IVUS) of the pulmonary arteries. The assessment of clinical and hemodynamic parameters, vasoreactivity, structural parameters of the pulmonary arteries according to IVUS data was performed at 2 visits before the first BPA and after a series of BPA. Results.The patients underwent 2.31.4 stages of BPA. The follow up was 160 (85; 248) days. Positive changes after a series of BPA were revealed in clinical (functional class, distance in the 6-minute walk test, level of brain natriuretic peptide) and hemodynamic (systolic and mean pulmonary artery pressure, right atrium pressure, etc.) parameters. The results of the AVT after BPA demonstrated a decrease in the portion of non-responders from 63.6 to 55.5%, and a group of responders (16.7%) has appeared. According to IVUS before and after AVT, the response to iloprost administration was observed basically in branches of subsegmental pulmonary arteries and initially corresponded to the process of vasodilation. However, after a series of BPA there was noted a paradoxical reaction in the middle section after the AVT a decrease in the vessel lumen and an increase in the thickness and area of the vessel wall. This effect is probably associated with the response to the test at the level of the microvasculature, as in pulmonary arterial hypertension before the onset of its pronounced structural changes. The data obtained confirm the reverse remodeling of the pulmonary vessels and the restoration of vasoreactivity after a series of BPA. Conclusion.BPA improves clinical and hemodynamic parameters, as well as pulmonary vasoreactivity, in inoperable patients with CTEPH. AVT may be included in the recommendations for the examination of patients with CTEPH to assess the effectiveness of BPA and determine the disease prognosis.

Keywords

• chronic thromboembolic pulmonary hypertension
• acute vasoreactivity testing
• balloon pulmonary angioplasty
• intravascular ultrasound