Incidence of chronic thromboembolic pulmonary hypertension in Thammasat University Hospital

BACKGROUND: Chronic thromboembolic pulmonary hypertension (CTEPH) is usually underrecognized due to nonspecific presentations. Undiagnosed CTEPH leads to unnecessary investigations for other diseases, and more importantly, increased morbidities and mortality. OBJECTIVES: The aim of this study was to define overall CTEPH incidence and the rate of CTEPH after acute pulmonary embolism (APE) in a tertiary care university hospital and to record risk factors, clinical and imaging characteristics, diagnosis assessment, and management methods. MATERIALS AND METHODS: The retrospective 5-year data, between 2012 and 2016, was extracted. Out of 1751 patients, we screened, 286 had, at least, evidence of pulmonary embolism. CTEPH was diagnosed in 20 patients, and 12 in this group had characteristics of combined APE or history of APE. RESULTS: The overall incidence of CTEPH was 37.8 cases per million patients, and the incidence of CTEPH after APE was 5.1%. The most common presentation was progressive exertional dyspnea (50%). All patients were diagnosed by computed tomography pulmonary angiography combined with echocardiogram. Surprisingly, only two patients had investigations with ventilation/perfusion lung scan. None underwent the preferred curative surgical treatment of pulmonary endarterectomy and two had balloon pulmonary angioplasty. All patients received anticoagulants, while only 5 patients were treated with pulmonary arterial hypertension-specific drugs. CONCLUSION: CTEPH was uncommon in our institute, with an underuse of the standard test. Suboptimal diagnosis assessment and management remain critical problems. Developing a properly trained CTEPH care team would improve patient outcomes, but cost/resources may be prohibitive for such a relatively rare disease. TRIAL REGISTRATION: TCTR20180220008 registered February 19, 2018.