INTERACTION OF AGE AND CORONARY-DISEASE AFTER VALVE-REPLACEMENT - IMPLICATIONS FOR VALVE SELECTION

The interaction of patient age and the presence of coronary artery disease (CAD) and its influence on survival were examined in 3,644 patients undergoing either aortic (AVR) or mitral (MVR) valve replacement with or without coronary artery bypass grafting (CABG) between 1974 and 1991. Emergency procedures were performed much more frequently in those undergoing MVR and CABG than in those undergoing AVR and CABG (18.8% and 6.7%, respectively). The adverse effect of CAD on median survival for patients of all ages undergoing either AVR or MVR was statistically significant (AVR without CAD 11.8 versus 8.7 years with CAD; MVR without CAD 12.7 versus 7.3 years with CAD; p < 0.0001). Survival in patients younger than 70 years without CABG who underwent either AVR or MVR was quite good (< 60 years: AVR, > 14 years; MVR, 15.4 years; 60 to 69 years: AVR, 10.4 years; MVR, 11.4 years). The most profound effect of CAD on patient survival after valve replacement was observed in patients 60 to 69 years of age who underwent MVR, in whom the median survival without CABG was 11.4 years versus 5.5 years with CABG (p < 0.0001). An emergency operative status was associated with a reduced early and late survival for those patients undergoing MVR, particularly those with CAD. By relating the Cox proportional hazard models for valve survival to patient survival, we found that, in those patients 70 years and older with and without CAD who underwent either AVR or MVR, the median patient swivel was reduced sufficiently (5.5 versus 8.1 years) to justify use of a bioprosthetic valve. Other factors being equal, we conclude that tissue valves appear to be most appropriate for MVR patients with CBD who are 60 years or older and for those older than 70 years who do not have CAD. Tissue valves also appear to be indicated for AVR patients with and without CAD who are 70 years and older. In patients without CAD who are younger than 70 years, the long-term survival after MVR or AVR is excellent and this finding suggests that mechanical valves may be preferable, as they are in all valve patients younger than 60 years.