Chronic Thromboembolic Pulmonary Hypertension: the Bedside.

Chronic thromboembolic pulmonary hypertension (CTEPH), included in group 4 PH, is an uncommon complication of acute pulmonary embolism (PE), in which emboli in the pulmonary vasculature do not resolve but rather form into an organized scar-like obstruction which can result in right ventricular (RV) failure. Here we provide an overview of current diagnosis and management of CTEPH. CTEPH management is complex with treatments that range from surgery, percutaneous interventions, to medical therapies. Current CTEPH medical therapies have largely been repurposed from pulmonary arterial hypertension (PAH). The diagnosis of CTEPH can be challenging, requiring a multimodality approach to differentiate from disease mimics. While these treatments improve symptoms, they may not reverse the underlying pathology of CTEPH.

Matusov Y ，Singh I ，Yu YR ，Chun HJ ，Maron BA ，Tapson VF ，Lewis MI ，Rajagopal S ... -  《-》

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 《-》

Update on chronic thromboembolic pulmonary hypertension.

Chronic, unresolved thromboemboli are an important cause of pulmonary hypertension (PH) with specific treatment strategies differing from other types of PH. Chronic thromboembolic pulmonary hypertension (CTEPH) is classified as group 4 PH by the World Health Organization. It is a rare, but underdiagnosed, complication of acute pulmonary embolism that does not resolve and results in occlusion of large pulmonary arteries with a fibro-thrombotic material. The etiology of CTEPH remains uncertain, and it is unknown why certain patients with acute pulmonary embolism develop this disorder. The evaluation for CTEPH is an important part of the evaluation for PH in general, and it is crucial not to overlook this diagnosis, as it is the only form of PH that is potentially curable. Patients diagnosed with CTEPH should be referred to an expert center for consideration of pulmonary endarterectomy, and surgical removal of the chronic thromboembolic material. Not all patients with CTEPH are surgical candidates, however, and there are emerging treatments-medical therapy and balloon pulmonary angioplasty-that have shown benefit in this patient population. Without treatment, CTEPH can lead to progressive pulmonary vascular obstruction, right heart failure, and death. Thus, it is important for clinicians to recognize this subtype of PH. In this review, we provide an overview of current understanding of the pathogenesis of CTEPH and highlight recommendations and recent advances in the evaluation and treatment of CTEPH.

Robbins IM ，Pugh ME ，Hemnes AR 《-》

Balloon pulmonary angioplasty in chronic thromboembolic pulmonary hypertension.

Chronic thromboembolic pulmonary hypertension (CTEPH) is caused by chronic stenosis or obstruction of the pulmonary arteries due to thromboembolism. Although previous studies have shown untreated CTEPH has a poor prognosis, the establishment of gold-standard therapies including pulmonary endarterectomy, balloon pulmonary angioplasty (BPA), and medical therapy has improved hemodynamics and right ventricular function, leading to good long-term survival. BPA is an important therapy for patients with inoperable CTEPH, although the procedure is currently limited to specific institutions and operators. This review discusses the development of the rapidly evolving field of CTEPH that includes improvements in imaging modalities and advances in surgical and interventional techniques.

Hirakawa K ，Yamamoto E ，Takashio S ，Hanatani S ，Araki S ，Suzuki S ，Kaikita K ，Matsushita K ，Ogo T ，Tsujita K ... -  《-》

Balloon Pulmonary Angioplasty in Chronic Thromboembolic Pulmonary Hypertension: New Horizons in the Interventional Management of Pulmonary Embolism.

Chronic thromboembolic pulmonary hypertension (CTEPH) is an underdiagnosed potential complication of acute or recurrent pulmonary thromboembolic disease. Multiple studies suggest that up to 5% of patients with acute pulmonary thromboembolic disease go on to develop CTEPH. The prognosis of untreated CTEPH is poor, but advances in medical and surgical treatments over the past few decades have improved patient outcomes. The gold standard and curative treatment for CTEPH is pulmonary endarterectomy; however, some patients are inoperable and others who have undergone pulmonary endarterectomy experience persistent or recurrent pulmonary hypertension despite medical therapy. In recent years, balloon pulmonary angioplasty has emerged as a primary and adjunctive treatment for these CTEPH patients at expert or specialized centers. This review outlines an approach to balloon pulmonary angioplasty for CTEPH, including clinical presentation and evaluation; patient selection and indications; treatment planning; equipment and technique; overcoming technical challenges; recognition and management of complications; postprocedural care and clinical follow-up; and expected outcomes.

Rivers-Bowerman MD ，Zener R ，Jaberi A ，de Perrot M ，Granton J ，Moriarty JM ，Tan KT ... -  《-》