Materials and Methods
This study complied with the Declaration of Helsinki and was approved by Nagoya Heart Center Ethics Committee (approved number: NHC2021-0330-12) on 30 March 2021. The need to obtain written informed consent was waived because of retrospective design of the study by Nagoya Heart Center Ethics Committee.
Between October 2008 and February 2021, all cardiac surgery cases performed at Nagoya Heart Center were screened and cases of isolated CABG were identified. We then divided patients into two groups: <80 years old (young group); and ≥80 years old (old group). Peri-operative results were investigated and compared between groups. Clinical data were gathered from medical charts, operative records and the in-hospital surgical database. Long-term results were assessed by direct contact or telephone interviews with patients, their families, or local doctors. Survival was assessed from January to May 2021.
The primary endpoint of this study was to investigate peri-operative results of the old group and compare them with those of the young group. The secondary endpoint was to assess long-term survival in the old group.
Data were analysed using SPSS version 22 statistical software (SPSS, Chicago, IL). Results are expressed as mean ± standard deviation. Continuous data were analysed using the Mann-Whitney U test or t-test, as appropriate. Categorical data were analysed using the χ2 test. Survival analysis was performed using the Kaplan-Meier method. Results were considered significant for values of p<0.05.