Pulmonary thromboendarterectomy in chronic thromboembolic pulmonary hypertension.

hypertension (CTEPH) develops in 1-3% of cases following acute pulmonary embolism. The disease is underdiagnosed and under-treated, as statistical studies have shown. Identification of patients with CTEPH is difficult since 90% of them have no apparent disturbance of the coagulation mechanism. CTEPH is a progressive disease, the result of the incomplete lysis of large organised thrombus in the main pulmonary artery and secondary branches, leading to obliterative pulmonary hypertension, right ventricular failure and subsequent death. Patients with mean pulmonary artery pressure (PAP) >30 mmHg have a five-year survival rate of 30%, while those with PAP >50 mmHg have 10% five-year survival. With surgical treatment (pulmonary thromboendarterectomy, PTE) the organised thromboembolic material is removed, pulmonary hypertension is reduced, right ventricular function and the overall clinical condition are improved in appropriately selected patients. PTE reduces pulmonary hypertension by reducing the ventilation-perfusion ratio, ending right ventricular dysfunction, limiting the retrograde extension of the obstructive thrombus and protecting against arteriopathological changes in the pulmonary vessels that remain patent.