Prognostic significance of the Karnofsky Performance Status score in patients with acute myocardial infarction: comparison with the left ventricular ejection fraction and the exercise treadmill test performance. The MILIS Study Group.

The prognostic significance of functional status has not been previously studied in the setting of acute myocardial infarction. We assessed the Karnofsky Performance Status (KPS) score, a simple functional status scale that is commonly used to categorize physical ability, in 849 patients with acute myocardial infarction who were enrolled in the Multicenter Investigation of the Limitation of Infarct Size (MILIS) study. We then compared the KPS score with other predictors of prognosis in these patients. In patients who presented with acute myocardial infarction, a lower KPS score (less than 8 on a scale of 1 to 10) 3 weeks before the index infarction was associated with a higher incidence of congestive heart failure, in-hospital cardiac arrest, and mortality during hospitalization, as compared with patients with KPS scores greater than or equal to 8 (each p less than 0.001). Cumulative 1-year and 4-year mortality rates were significantly higher in patients with KPS scores less than 8, as compared with patients with KPS scores greater than or equal to 8 (42.5% vs. 12.6% at 1 year and 61.6% vs 25.1% at 4 years, respectively; both p less than 0.001). The left ventricular ejection fraction on admission was significantly lower in patients with KPS scores less than 8, as compared with those with KPS scores greater than or equal to 8 (p less than 0.019). The cumulative mortality rate was equally well predicted by low KPS score and by left ventricular ejection fraction (both p less than 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)