Chronic Thromboembolic Pulmonary Hypertension.

Chronic thromboembolic pulmonary hypertension (CTEPH), defined as precapillary pulmonary hypertension (PH) by right heart catheterization and imaging consistent with chronic thromboembolism, is a long-term complication of pulmonary embolism (PE). Pathobiological mechanisms involve pulmonary artery occlusion from organized thromboembolic material despite at least three months of uninterrupted therapeutic anticoagulation following acute PE and secondary microvasculopathy. Delay in diagnosis and management of CTEPH is associated with poor outcomes. High clinical suspicion, comprehensive assessment of residual dyspnea or exercise intolerance in the aftermath of PE and accurate interpretation of computed tomography pulmonary angiography (CTPA) are pivotal steps in the diagnosis. Ventilation-perfusion (V/Q) scan is the preferred initial radiologic screening tool as normal V/Q essentially rules out CTEPH. Any mismatched perfusion defect on the V/Q scan in the setting of PH or any finding compatible with chronic thromboembolism on CTPA should prompt referral to an expert CTEPH center. Once the diagnosis is verified, all eligible patients should be offered pulmonary thromboendarterectomy (PTE). Pulmonary vasodilators or balloon pulmonary angioplasty are safe and effective in inoperable or post-PTE persistent/recurrent CTEPH. During the course of their disease, a patient may receive a combination of treatments, at times consisting of all three strategies. Lifelong therapeutic anticoagulation is recommended for CTEPH.

Teerapuncharoen K ，Bag R 《-》

Recent progress in the diagnosis and management of chronic thromboembolic pulmonary hypertension.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a form of pulmonary hypertension caused by non-resolving thromboembolisms of the pulmonary arteries. In Japan, in contrast to Western countries, CTEPH is more prevalent in women. A Japanese multicenter study reported that a form of CTEPH unrelated to deep vein thrombosis is associated with HLA-B⁎5201, suggesting that this form of CTEPH may be associated with vasculopathy. CTEPH can be cured by pulmonary endarterectomy, provided that the thrombi are surgically accessible; thus, early diagnosis is important, and all patients with exertional dyspnea should be evaluated for pulmonary hypertension. Ventilation/perfusion scans provide an excellent non-invasive means to distinguish CTEPH from pulmonary arterial hypertension. Similarly, computed tomographic pulmonary angiograms allow for the detection of thrombi and evaluation of pulmonary hemodynamics in a minimally invasive manner. Importantly, the absence of subpleural perfusion on pulmonary angiograms can suggest the presence of small vessel disease. Small vessel disease might be involved in the pathogenesis of CTEPH, and its detection is essential in preventing operative death. Although no modern therapies for pulmonary arterial hypertension have been approved for treatment of CTEPH, a recent randomized control trial of riociguat in patients with CTEPH demonstrated that riociguat significantly improved 6-min walking distance. Further investigations into treatments that target endothelial dysfunction and hyperproliferative CTEPH cells are needed. Recently, balloon pulmonary angioplasty has emerged as a promising treatment modality in Japan. A specialized medical team, including at least one expert surgeon, should make decisions regarding patients' candidacy for pulmonary endarterectomy and/or balloon pulmonary angioplasty.

Tanabe N ，Sugiura T ，Tatsumi K 《-》

Chronic thromboembolic pulmonary hypertension.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a form of pulmonary hypertension (PH) characterized by the persistence of thromboembolic obstructing the pulmonary arteries as an organized tissue and the presence of a variable small vessel arteriopathy. The consequence is an increase in pulmonary vascular resistance resulting in progressive right heart failure. CTEPH is classified as group IV pulmonary hypertension according to the WHO classification of pulmonary hypertension. CTEPH is defined as precapillary pulmonary hypertension (mean pulmonary artery pressure ≥ 25 mmHg with a pulmonary capillary wedge pressure ≤ 15 mmHg) associated with mismatched perfusion defects on ventilation-perfusion lung scan and signs of chronic thromboembolic disease on computed tomography pulmonary angiogram and/or conventional pulmonary angiography, in a patient who received at least 3 months of therapeutic anticoagulation. CTEPH as a direct consequence of symptomatic pulmonary embolism (PE) is rare, and a significant number of CTEPH cases develop in the absence of history of PE. Thus, CTEPH should be considered in any patient with unexplained PH. Splenectomy, chronic inflammatory conditions such as inflammatory bowel disease, indwelling catheters and cardiac pacemakers have been identified as associated conditions increasing the risk of CTEPH. Ventilation-perfusion scan (V/Q) is the best test available for establishing the thromboembolic nature of PH. When CTEPH is suspected, patients should be referred to expert centres where pulmonary angiography, right heart catheterization and high-resolution CT scan will be performed to confirm the diagnosis and to assess the operability. Pulmonary endarterectomy (PEA) remains the gold standard treatment for CTEPH when organized thrombi involve the main, lobar or segmental arteries. This operation should only be performed by experienced surgeons in specialized centres. For inoperable patients, current ESC/ERS guidelines for the diagnosis and treatment of pulmonary hypertension recommend the use of riociguat and say that off-label use of drugs approved for PAH and pulmonary angioplasty may be considered in expert centres.

O'Connell C ，Montani D ，Savale L ，Sitbon O ，Parent F ，Seferian A ，Bulifon S ，Fadel E ，Mercier O ，Mussot S ，Fabre D ，Dartevelle P ，Humbert M ，Simonneau G ，Jaïs X ... -  《-》

Evaluation and Management of Chronic Thromboembolic Pulmonary Hypertension.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a treatable form of pulmonary hypertension and right heart failure. CTEPH (group 4 pulmonary hypertension) is caused by persistent organized thromboembolic obstruction of the pulmonary arteries from incompletely resolved acute pulmonary embolism. CTEPH also may present without prior VTE history, which can contribute to its underrecognition. The true incidence of CTEPH is unclear, but is estimated to be approximately 3% after acute pulmonary embolism. V˙/Q˙ scintigraphy is the best screening test for CTEPH, with CT scan imaging and other advanced imaging methods now playing a larger role in disease detection and confirmation. Perfusion defects on V˙/Q˙ scintigraphy in the setting of pulmonary hypertension are suggestive of CTEPH, but pulmonary angiography and right heart catheterization are required for confirmation and treatment planning. CTEPH potentially is curative with pulmonary thromboendarterectomy surgery, with mortality rates of approximately 2% at expert centers. Advances in operative techniques are allowing more distal endarterectomies to be performed successfully with favorable outcomes. However, more than one-third of patients may be considered inoperable. Although these patients previously had minimal therapeutic options, effective treatments now are available with pharmacotherapy and balloon pulmonary angioplasty. Diagnosis of CTEPH should be considered in all patients with suspicion of pulmonary hypertension. Treatments for CTEPH have advanced with improvements in outcomes for both operable and inoperable patients. Therapy should be tailored based on multidisciplinary team evaluation to ensure optimal treatment response.

Yang J ，Madani MM ，Mahmud E ，Kim NH ... -  《-》

Update in the management of chronic thrombo-embolic pulmonary hypertension.

Ribas Sola J ，Sánchez-Corral Mena MÁ ，Riera-Mestre A 《-》