Introduction: Conventional risk stratification after acute myocardial infarction is usually based on the extent of myocardial damage and its clinical consequences. However, nowadays, more aggressive therapeutic strategies are used, both pharmacological and invasive, with the aim of changing the course of the disease.
Objectives: To evaluate whether the number of drugs administered can influence survival of these patients, based on recent clinical trials that demonstrated the benefit of each drug for survival after acute coronary events.
Methods: This was a retrospective analysis of 368 consecutive patients admitted to our ICU during 2002 for acute coronary syndrome. A score from 1 to 4 was attributed to each patient according to the number of secondary prevention drugs administered--antiplatelets, beta blockers, angiotensin-converting enzyme inhibitors and statins--independently of the type of association. We evaluated mortality at 30-day follow-up.
Results: Mean age was 65 +/- 13 years, 68% were male, and 43% had ST-segment elevation acute myocardial infarction. Thirty-day mortality for score 1 to 4 was 36.8%, 15.6%, 7.8% and 2.5% respectively (p < 0.001). The use of only one or two drugs resulted in a significant increase in the risk of death at 30 days (OR 4.10, 95% CI 1.69-9.93, p = 0.002), when corrected for other variables. There was a 77% risk reduction associated with the use of three or four vs. one or two drugs. The other independent predictors of death were diabetes, Killip class on admission and renal insufficiency.
Conclusions: The use of a greater number of secondary prevention drugs in patients with acute coronary syndromes was associated with improved survival. A score of 4 was a powerful predictor of mortality at 30-day follow-up.