Use of the cardiac-catheterization laboratory in a defined population.

We evaluated trends in the use of the cardiac-catheterization laboratory from 1973 through 1977 in a well-circumscribed population in southeastern Minnesota. A total of 346 patients (248 male and 98 female patients) underwent coronary arteriography, left ventriculography, or cardiac catheterization, and there were 369 visits to the catheterization laboratory. The total number of catheterization-laboratory visits per 10,000 population increased from 4.3 in 1973 to 11.5 in 1977. According to individual category, the rates for coronary arteriography increased more than fourfold during the five-year period, whereas the rates for cardiac catheterization period, whereas the rates for cardiac catheterization showed no substantial change. On the basis of the 1977 rate for all visits to the catheterization laboratory and under conditions similar to those in this community, a population of approximately 230,000 would be required to ensure use of a catheterization laboratory at the suggested minimum level of 300 adult examinations per year.