BACKGROUND: Few studies have used the cumulative sum method to examine the initial performance of a newly appointed cardiac surgery team at a low-volume hospital. METHODS AND RESULTS: In the 4 years from April 2002 to December 2006, 274 cases of open-heart surgery were performed and the overall mortality and morbidity rates were 4.01% and 5.84%, respectively. The respective rates for coronary, valvular and aortic surgery were 2.05% and 2.74%, 3.61% and 7.23%, and 11.1% and 13.3%. The overall cumulative sum curve was below the 80% upper alarm line since the 58(th) case and below the 80% lower alarm line since the 139th case. The respective values for the cumulative sum curves of valvular and coronary surgery were the 1st and 41st cases, the 22nd and the 76th cases, but for aortic surgery the cumulative sum curve remained below the 80% upper alarm line since the 1st case but did not reach below the 80% lower alarm line CONCLUSIONS: An open-heart surgery unit at a low-volume hospital could compete with a high-volume hospital if it has a safe launching and low mortality and morbidity rates. The predictor of a safe launching is not the annual volume, but the cumulative experience of the surgical team.
BACKGROUND: Few studies have used the cumulative sum method to examine the initial performance of a newly appointed cardiac surgery team at a low-volume hospital. METHODS AND RESULTS: In the 4 years from April 2002 to December 2006, 274 cases of open-heart surgery were performed and the overall mortality and morbidity rates were 4.01% and 5.84%, respectively. The respective rates for coronary, valvular and aortic surgery were 2.05% and 2.74%, 3.61% and 7.23%, and 11.1% and 13.3%. The overall cumulative sum curve was below the 80% upper alarm line since the 58(th) case and below the 80% lower alarm line since the 139th case. The respective values for the cumulative sum curves of valvular and coronary surgery were the 1st and 41st cases, the 22nd and the 76th cases, but for aortic surgery the cumulative sum curve remained below the 80% upper alarm line since the 1st case but did not reach below the 80% lower alarm line CONCLUSIONS: An open-heart surgery unit at a low-volume hospital could compete with a high-volume hospital if it has a safe launching and low mortality and morbidity rates. The predictor of a safe launching is not the annual volume, but the cumulative experience of the surgical team.