Clinical features and management of chronic thromboembolic pulmonary hypertension in Thai.

BACKGROUND: The incidence and clinical features of chronic thromboembolic pulmonary hypertension (CTEPH) in Thailand are unknown. This may be due to the difficulties in diagnosis, poor disease recognition and non-specific presenting symptoms and signs. With the new revolution of diagnostic tools and advanced knowledge about this condition, CTEPH is now discovered much more often.

STUDY DESIGN: Retrospective cross-sectional study.

OBJECTIVE: To evaluate common risk factors, symptoms, signs, commonly used investigations, treatment and results of treatment in Thai patients with CTEPH.

MATERIAL AND METHOD: All patients with confirmed CTEPH diagnoses were selected for analysis in this study. We evaluated characteristics of patients with CTEPH at Siriraj hospital. All CTEPH patients' data included demographics, symptoms, signs, investigations, treatments, outcome and risk factors such as malignancy; previous deep vein thrombosis, immobilization, and congenital thrombophilia were recorded.

STATISTICAL ANALYSIS: The descriptive statistics were used in this study. Categorical data and continuous data presented in term of percent and mean with standard deviation respectively.

RESULTS: fourteen patients had confirmed diagnoses of CTEPH, five patients were male and 9 were female. The age of patients varied from 28 to 79-years-old. Mean age was 55-years-old. The most common presenting symptoms and signs were dyspnea (100%), followed by leg edema (78.6%), tachypnea (71.4%) and accentuation of pulmonic component of second heart sound (loud P2) (57.1%). At the time of diagnosis, four out of 14 patients were in NYHA class II, ten were in NYHA class III, and none of them was in NYHA class IV. Idiopathic CTEPH was found in 54.1% of patients. Congenital and acquired thrombophilia were the frequent risk factors found in our series. The most frequent radiographic abnormalities included enlarged pulmonary trunk, right atrium/right ventricle (RA/RV) dilatation, and cardiomegaly followed by prominent pulmonary trunk. Echocardiography findings were elevated right ventricular systolic pressure (RVSP); ranges varied from 60 mmHg to 137 mmHg (mean was 107.48 mmHg). The most common finding of arterial blood gas in APE patients was respiratory alkalosis with hypoxemia. The most frequent diagnostic tool used was ventilation-perfusion lung scan. Treatment of CTEPH patients was by anticoagulant, pulmonary thromboendarterectomy and inferior vena cava filter insertion. The success rate of surgical thromboendarterectomy in our institute was about 80%.

CONCLUSION: Characteristics of CTEPH patients are unique and different from acute pulmonary embolism in aspects of clinical presentations, risk factors, investigation, common findings, treatment and outcome.