Improved early results after aortic valve replacement: analysis by surgical time frame

Primary aortic valve replacement was performed in 430 patients. It was an isolated procedure in 339 and was combined with coronary artery bypass grafting in 91. Of these patients, 282 underwent operation from 1970 through 1976 (time frame 1) and 148 from 1980 through 1985 (time frame 2). They were divided into subgroups by age, New York Heart Association functional class, combined coronary artery bypass graft, and valvular lesion. Overall hospital mortality was 7.7% (time frame 1 = 10.6% versus time frame 2 = 2.0%; p less than 0.01). Overall, functional class III or IV was the strongest predictor of hospital mortality (p less than 0.001). Association of coronary artery bypass graft was the next strongest predictor of hospital mortality (p less than 0.01), and it retained its predictive value in time frame 2. Overall, hospital mortality was higher in patients older than 55 years (10.5% versus 3.5%; p less than 0.05). There were no hospital deaths in patients younger than 55 years in time frame 2. Type of valvular lesion was not a predictor of hospital mortality. Hospital mortality in patients receiving cardioplegia was 2%. Cardioplegia use has lessened the effect of age and functional class as predictors of hospital mortality after primary aortic valve replacement. Earlier operation in time frame 2 played a substantial role in the overall improvement of early results.