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142 Pulmonary Hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is a form of pulmonary hy‐ pertension caused by obstruction and vascular remodeling of the pulmonary arteries after a pulmonary embolism [1]. Once considered rare, CTEPH is likely under-diagnosed and its true prevalence is still uncertain [2,3]. CTEPH is a consequence of the persistence and fibrous organization of clots in the pulmonary arteries after one or more acute pulmonary emboli. Recent research has provided evidence, suggesting that the old view of CTEPH as a disease caused solely by obliteration of pulmonary arteries by organized thrombus con‐ stitutes a very superficial understanding of the consequences of pulmonary thromboem‐ boli [3]. In fact, pulmonary embolism, either as a single episode or as recurrent episodes, is probably the trigger followed by progressive pulmonary vascular remodeling leading to elevated pulmonary vascular resistance, progressing to right ventricular (RV) failure [4]. Thanks to enhanced vascular and cardiac imaging, less-invasive diagnostic work-up of CTEPH have become widely available. Doppler ultrasound echocardiography and pul‐ monary ventilation/perfusion (V/Q) scintigraphy are two excellent and complementary ex‐ aminations for CTEPH [5]. Computed tomography (CT) and pulmonary angiography are the two best tools to decide on the operability of the endovascular lesions. [6]. Equally important, CTEPH is a type of pulmonary hypertension (PH) that is unique because it is potentially curable by PEA [7, 8]. Indeed, the prognosis of CTEPH was transformed by this technique [8]. The first surgery for CTEPH was performed in 1958 [9]. The mortality in the early surgical series was 22% but with advances in surgery and improved and peri‐ operative care, it has decreased to about 4% [10, 11].

© 2013 Badidi and Nazi; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 Badidi and Nazi; licensee InTech. This is a paper distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
