ENDOVASCULAR TREATMENT OF THE RESIDUAL THROMBOEMBOLIC PULMONARY HYPERTENSION AFTER PULMONARY THROMBENDARTERECTOMY WITH THE DENERVATION SYSTEM SYMPLICITY

Aim. To assess the safety and efficacy of radiofrequency denervation of pulmonary artery (PA) with the Simplicity system in patients with residual pulmonary hypertension (PH) after the thromberarterectomy surgery.

Material and methods. To the study, 12 patients included, with the signs of residual PH (by echocardiography data, mean PH pressure ≥25 mmHg), who had undergone surgery (thrombendarcterectomy) for chronic thromboembolic PH. Mean time interval between the diagnosis of PH and pulmonary denervation was 8,5 years. After catheterization of the right chambers of the heart and tensiometry in small circle circulation, the spot circular radiofrequency denervation performed of the right and left PH at the area of ostia, with ablation catheter Simplicity. The success was defined by decrease of mean PA pressure >10 mmHg, absence of complications, exercise tolerance increase after the procedure immediately and in 12 months.

Results. At long term period after the intervention there was significant decrease of mean PA pressure from 58±6 to 33±4 mmHg (p<0,01), of pulmonary vascular pressure from 8,6±2,1 to 3,2±1,4 mmHg (p<0,01) and increase of exercise tolerance from 321±19 m to 487±29 m (p<0,01). During the follow up period, 1 patient died in 8 months after inclusion due to severe gastrointestinal bleeding. The rest did not present with adverse events or non­planned hospitalizations. Nine patients noted significant improvement of general health, decrease of dyspnea and fatigue, 3 patients had discontinued sildenafil. There were no complications at PA radiofrequency ablation procedure (death, arrhythmias, PA perforation, acute PA thrombosis in the place of access, bleeding).

Conclusion. Utilization of the Simplicity system in PA denervation is safe and effective. Further randomized studies in need to confirm clinical benefits from the procedures in PH patients.

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