Progress Studyof590Consecutive Nonsurgical Cases ofCoronary Disease Followed 5-9Years I. Arterographic Correlations

in no category was themortality far different from the average. Groupinginto three larger categories yielded only small,statistically insignificant differences. Likewise, smalldifferences were found if the cases were dividedaccording to the severity of narrowing (table 7).Only cases with two subtotal obstructions had aconsiderably higher mortality than the others, butthis groupwas small andthe difference in mortalityrate doesnotattain statistical significance.To determine the influence of the third arterybeing moderately