目標：為探討論病例計酬實施前後，冠狀動脈繞道手術病患死亡情形的變化及相關因素。方法：為介入前後自然實驗研究，以全民健保88年7月實施冠狀動脈繞道手術論病例計酬前18個月與後10個月中，接受冠狀動脈繞道手術患者為研究對象，共5,607人次；以住院期間死亡率與住院併出院後30日內死亡率作為測量指標。結果：論病例計酬實施後，冠狀動脈繞道手術之住院期間及住院併出院後30日內死亡率，在控制其他因素後並無統計上的顯著不同，顯示國內實施論病例計酬後，冠狀動脈繞道手術品質未顯著受到影響。在醫院特質方面，公立醫院雖住院期間死亡率較私立醫院高，然住院併出院後30日內死亡率則是私立醫院較高。而女性、年齡大於65歲、患有急性心肌梗塞、充血性心衰竭、週邊血管疾病、糖尿病或中風等病史，住院期間併發症、住院日較短，及由服務量較低之醫院或醫師執行手術之病患，其住院併出院後30日內死亡率較高。結論：住院併出院後30日內死亡率較適合用來監控CABGs手術品質之指標，且高服務量醫院及醫師的手術品質較佳。建議：健保局未來應加強低服務量醫院或醫師的審查與輔導，並持續監控醫療品質。此外，醫療供給者除應加強醫院低服務量醫師的手術訓練外，對於患有相關合併症之高危險群病患，亦應特別留意其照顧品質，以降低術後死亡的風險。

　　　　　Objective: To investigate the risk factors and changes in the mortality rate in patients with coronary artery bypass grafting surgery (CABGs) before and after the implementation of a case-based prospective payment system (CPS) in July 1999. Methods: The 5,607 patients who received CABGs from January 1998 (18 months before CPS) to April 2000 (10 months after CPS) were extracted from the National Health Insurance data. Their mortality rate of in-hospital and in-hospital plus within 30-days of discharge before and after the implementation of CPS was analyzed using a natural experiment study. The relative factors of mortality rate were also analyzed in this study. Results: After controlling for the confounding factors, the mortality rate of in-hospital and in-hospital plus within 30-days after discharge did not change significantly following the implementation of CPS for the patients received CABGs. It showed that CPS might not influence the medical quality of CABGs. The in-hospital mortality rate of public hospitals is higher than private hospitals. However, the mortality rate of in-hospital plus within 30-days of discharge was higher in the private hospitals. The factors such as female gender, being older than 65 year-old, acute myocardial infraction, congestive heart failure, cerebrovascular disease, diabetes, stroke, in-hospital complication, shorter length of stay, and hospitals or physicians with a lower volume of CABGs were related to a higher mortality rate. Conclusions: The mortality rate of in-hospital plus within 30-days of discharge could be used for monitoring medcial quality of CABGs. The Bureau of National Health Insurance should monitor the medical quality of low-volume hospitals or physicians. Health care providers should also pay attention to the surgery training for the low-volume physicians to reduce mortality rate.