Mortality and recurrent cardiac events after coronary artery bypass graft: long term outcomes in a population study.
OBJECTIVE
To determine 30 day mortality, long term survival, and recurrent cardiac events after coronary artery bypass graft (CABG) in a population.


METHODS
Follow up study of patients prospectively entered on to a cardiothoracic surgical database. Record linkages were used to obtain data on readmissions and deaths.


METHODS
8910 patients undergoing isolated first CABG between 1980 and 1993 in Western Australia.


METHODS
30 day and long term survival, readmission for cardiac event (acute myocardial infarction, unstable angina, percutaneous transluminal coronary angioplasty or reoperative CABG).


RESULTS
There were 3072 deaths to mid 1999. 30 day and long term survival were significantly better in patients treated in the first five years than during the following decade. The age of the patients, proportion of female patients, and number of grafts increased over time. An urgent procedure (odds ratio 3.3), older age (9% per year) and female sex (odds ratio 1.5) were associated with increased risk for 30 day mortality, while age (7% per year) and a recent myocardial infarction (odds ratio 1.16) influenced long term survival. Internal mammary artery grafts were followed by better short and long term survival, though there was an obvious selection bias in favour of younger male patients.


CONCLUSIONS
This study shows worsening crude mortality at 30 days after CABG from the mid 1980s, associated with the inclusion of higher risk patients. Older age, an acute myocardial infarction in the year before surgery, and the use of sephenous vein grafts only were associated with poorer long term survival and greater risk of a recurrent cardiac event. Female sex predicted recurrent events but not long term survival.
Bradshaw
P J
PJ
School of Population Health, University of Western Australia, Western Australia, Australia. pamela.bradshaw@health.wa.gov.au
Jamrozik
K
K
Le
M
M
Gilfillan
I
I
Thompson
P L
PL
D000367:Age Factors; D000368:Aged; D001026:Coronary Artery Bypass / Q000379:methods / Q000401:mortality*; D003327:Coronary Disease / Q000601:surgery*; D016757:Death, Sudden, Cardiac / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010359:Patient Readmission / Q000706:statistics & numerical data; D012008:Recurrence; D012086:Reoperation / Q000706:statistics & numerical data; D012737:Sex Factors; D016019:Survival Analysis; D016896:Treatment Outcome