RÉSUMÉ
BACKGROUND AND OBJECTIVES: Little information is available regarding adult patients with congenital heart disease (CHD) who needed unscheduled hospitalization (USH). This paper aims to elucidate the clinical features of adult patients with CHD requiring USH. SUBJECTS AND METHODS: Study subjects included patients with CHD aged 18 years or older who were hospitalized at our facility during a 5-year study period. Medical records were retrospectively reviewed and data regarding USH were collected. Patient's background, underlying heart disease, cause of hospitalization, and prognosis (second USH regardless of cause or death) were examined. RESULTS: Overall, 959 CHD patients underwent a total of 1761 hospitalizations, including 145 patients who were unexpectedly hospitalized 239 times. The median age at USH was 27 years old. Of the 959 patients, 54% were male. Underlying heart diseases included repaired tetralogy of Fallot (21%), single ventricular physiology after Fontan operation (17%), and Eisenmenger syndrome (12%). The causes of USH included arrhythmia (40%), heart failure (20%), infectious disease (13%), and hemorrhage or thrombus (13%). A total of 48 patients required readmission. In total, 13 patients died, including four hospital deaths. The USH-free survival rate was 77% for 1 year and 58% for 3 years. CONCLUSION: The rate of USH was high for adults with complicated CHD. Common causes of USH included arrhythmia, heart failure, hemorrhage-related or thrombus-related conditions and infection. These data provide the current status of medical care for adult CHD patients in Japan and their therapeutic needs.