OBJECTIVES: Despite national and international guideline recommendations, only a small proportion (estimated in 39%) of ST elevation myocardial infarctions (STEMI) that arrive in the 8-hour "therapeutic window" in Colombia receive thrombolytic treatment; our objective was to estimate the budget impact of a gradual implementation of this therapeutic approach. METHODS: In our excel based model we applied ISPOR's principles of good practice for budget impact analysis. The perspective was from the Colombian health system; we used a 5-year time horizon (2012-2016). The model compared two different scenarios: continuing the current practice, with no increase in the proportion of thrombolized patients, while the other (Scenario 2) assumed a gradual increase (5 percentage points) of thrombolized patients, and an increase in tenecteplase use from (3 to 25% of all patients) along the five year period.  RESULTS: Our estimated total cost of STEMI in Colombia for 2012, with 984 patients thrombolyzed nationwide, was US$728,291. With an increase in the use of thrombolysis (Scenario 2) the cost would increase by US$ 42,270 during the second year, US$87,596 during the third year, US$136,051 in the fourth year and US$187,716 in the  fifth year (with a 15% overall increase in the number of thrombolyzed patients). This cost increase is due to an increase in the target population (estimated by official demographic projections), an increase in the proportion of patients with myocardial infarction receiving thrombolyisis and an increase in those receiving tenecteplase instead of streptokynase. CONCLUSIONS: Our country needs to allocate resources to prevent and treat cardiovascular diseases; applying current standards established in evidence-based guidelines of myocardial infarction treatment should be an affordable investment.