Combination of the killip and TIMI classifications for early risk stratification of patients with acute ST elevation myocardial infarction

Objective: The Killip classification and the Thrombolysis in Myocardial Infarction (TIMI) score have been proven to be useful tools for the early risk stratification of patients with acute myocardial infarction (MI). The Killip classification is simpler and less time consuming compared to the TIMI score. We sought to evaluate the added value of applying the TIMI score to patients prestratified with the Killip classification. Methods: A total of 1,773 consecutive acute MI patients were hospitalized in 25 coronary care units operating in Israel, and were followed up to 1 year. Results: Higher Killip class was associated with increased 1-year mortality: 6, 24, 42 and 60% in Killip 1-4, respectively. Applying the TIMI score to Killip 1 patients resulted in further stratifying the patients to low-, medium- and high-risk patient groups with 1, 8 and 19% 1-year mortality rates. Conclusions: The Killip classification is a useful tool for early risk stratification of acute MI patients. Applying the TIMI score to patients classified as Killip 1 further stratified them into low-, medium- and high-risk subgroups significantly improving stratification by the Killip classification alone.