The current trends of mortality following congenital heart surgery: the Japan Congenital Cardiovascular Surgery Database

OBJECTIVES: Whereas surgical outcomes of congenital heart surgery have improved during the past two decades, there are still measurable postoperative mortalities in this field. This study is aimed at evaluating the current situation of mortality following congenital heart surgery. METHODS: Data on all registered 28 810 patients in The Japan Congenital Cardiovascular Surgery Database (JCCVSD) between 2008 and 2012 were analysed, except for patients with degenerative cardiomyopathy including dilated, restrictive and hypertrophic cardiomyopathy, and pathologically or histologically malignant cardiac tumours. The number of registered cases increased every year, and reached similar to 9000 cases in 2012. The median age at surgery was 0.8 years (range, 0-82). More than half of the patients (54%) who underwent surgery were <1 year old, and 6.0% of all patients were over 18 years old (adults). In this study, all mortalities within 90 days after the operation and mortality at discharge beyond 90 days of hospitalization were defined as '90-day and in-hospital mortality'. RESULTS: The 30-, 90-day and in-hospital mortality rates were 2.3, 3.5 and 4.5%, respectively. The mean and median durations from surgery to death were 61 +/- 89 and 28 days (range, 0-717), respectively. Whereas 658 mortalities (51%) occurred within 30 days of surgery, 265 (21%) occurred later than 90 days after surgery. A total of 3630 patients (13%) were hospitalized for more than 90 days after the operation; of those, 3365 patients survived at discharge (93%). Cardiac problems were the most frequent causes of death after the surgery at any point in time, and 7.1 per 1000 patients died at over 30 days after the operation due to solely cardiac. CONCLUSIONS: The investigation of JCCVSD revealed that about a half of mortalities occurred later than 30 days; hence 90-day and in-hospital mortality would be a good discriminator that accurately represented the current situation of mortality after congenital heart surgery. Mortalities long after the operation due to post-cardiotomy heart failure without any other lethal complications were still not rare.