Chronic Thromboembolic Pulmonary Hypertension (CTEPH): A Surgically Curable Cause of Pulmonary Hypertension

Abstract

Introduction. Chronic thromboembolic pulmonary hypertension (CTEPH) is defined as pulmonary hypertension (PH) observed after a minimum period of 3 months following at least one episode of pulmonary embolism, excluding other causes of PH. Case report. We present the case of a 45-year-old female patient who reported of tiredness and progressive dyspnea. The physical examination showed O2 Sat of 95% at rest and of 75% at effort without the 02 catheter. She also had P2 hyperphonesis. For the etiologic investigation, a transthoracic echocardiography was firstly requested, showing increased right chambers, preserved left ventricular systolic function, and pulmonary artery systolic pressure (PASP) of 93 mmHg. In the ventilation/perfusion lung scintigraphy, the perfusion study showed a heterogeneous radiopharmaceutical distribution, and the ventilation study showed a discordant radiopharmaceutical distribution, with ventilation preserved in both lungs. Since there was a high probability of CTEPH, a chest tomography and a pulmonary arteriography were requested. The chest CT showed chronic thromboembolic pulmonary signs, with a proximal thrombus in the right pulmonary artery and right interlobar artery. Pulmonary arteriography showed proximal obstruction in the right and left branches of the pulmonary artery, also evidencing that the only perfused area was the left superior lobe. A right cardiac catheterization was made to access hemodynamic factors, with a pulmonary vascular resistance (PVR) of 12.5 Woods. The patient was then indicated for pulmonary thromboendarterectomy, due to favorable hemodynamic and operable location of the thrombus. The operation was successful, and PASP decreased from 86 mmHg (preoperative) to 43 mmHg (immediate postoperative). Conclusion. CTEPH is a rare complication of pulmonary embolism. Its delay in diagnosis and lack of knowledge in the medical community lead to patients with chronic and worsening dyspnea. It is important to consider CTEPH in patients with PH or chronic worsening dyspnea, as CTEPH is the only potentially curable cause of PH.