86 - Pulmonary Hypertension Due to Chronic Thromboembolic Disease: Group 4

Abstract

Chronic thromboembolic pulmonary hypertension (CTEPH) is one of the five World Health Organization (WHO) classifications of pulmonary hypertension. This disease is often under-recognized and may represent a larger population than in the WHO group 1 of pulmonary arterial hypertension. CTEPH is unique among the various forms of pulmonary hypertension due to the potential for surgical cure with pulmonary thromboendarterectomy (PTE). Typically, CTEPH is preceded by an incident pulmonary embolism in approximately 75% of patients. The acute thrombosis is replaced by chronic intravascular scar, which can ultimately lead to pulmonary arterial hypertension due to increased flow shunted from the obstructed vascular bed into the open vascular beds. A high index of suspicion is necessary to make the diagnosis of CTEPH, with special attention paid to patients with unexplained dyspnea and those with dyspnea after an acute pulmonary embolism. Screening for CTEPH consists of a ventilation-perfusion scan and a transthoracic echocardiogram; the disease is confirmed with pulmonary angiography. Patients with CTEPH should be referred to specialized centers with expertise in both PTE and balloon pulmonary angioplasty. PTE surgery is curative in most patients and has durable long-term improvements in symptoms and survival. For those who are not candidates for PTE due to either the distal nature of the disease or comorbidities, there is emerging evidence of benefit with medical therapy, such as with riociguat, and balloon pulmonary angioplasty. Regardless of treatment modality, CTEPH is an indication for lifelong anticoagulation to prevent recurrence.