Background: The number of adult patients with congenital heart disease (CHD) has increased rapidly and represents a major challenge in cardiovascular medicine. Data regarding the prevalence and characteristics of adult CHD in Thai population over the past decade are lacking.

Material and Method: Patients who underwent comprehensive transthoracic echocardiographic study at Siriraj Hospital during January 2003 to May 2013 with the diagnosis of unrepaired CHD and complete data were enrolled in the study. Patients with uncertain diagnosis, prior cardiac intervention, bicuspid aortic valve, patent foramen ovale, mitral valve prolapse, isolated persistent left superior vena cava and congenital cardiomyopathies were excluded.

Results: Among 27,132 patients underwent transthoracic echocardiography, 1,082 (age 36.7±14.7 years, 75.3% female) had the diagnosis of CHD and the prevalence was 4.0% (95% confidence interval = 3.76-4.23%). The majority were isolated simple left-to-right shunt lesions: atrial septal defect (43%), ventricular septal defect (27%) and patent ductus arteriosus (11%). Eisenmenger syndrome was reported in 77 patients (age 39.1±10.8 years, 71.4% female). Pulmonic stenosis and Ebstein’s anomaly were reported in 2.9% and 2.8% of patients, respectively. Tetralogy of Fallot was the most common cyanotic defect (3.5%). The combinations of shunts and/or right-sided obstructive lesions were reported in 4.8%.

Conclusion: The prevalence of adult CHD diagnosed by echocardiography at Siriraj Hospital was 4.0% and atrial septal defect was the most common form. Simple shunt lesions represent more than 80% of patients. Female predominance was reported in all common forms of CHD. Echocardiography is fundamental for the diagnosis and management of patients with CHD.

Keywords: Adult, Congenital heart disease, Echocardiography