From the Guidelines
The evidence strongly supports a door-to-balloon time of 90 minutes or less for patients with ST-elevation myocardial infarction (STEMI), with 60 minutes being an ideal target that yields even better outcomes. For every STEMI patient, healthcare systems should aim for a door-to-balloon time of 60 minutes whenever possible, as shorter times correlate with reduced mortality rates, smaller infarct sizes, and better preservation of left ventricular function 1, 2, 3, 4, 5, 6. The 90-minute threshold represents the maximum acceptable time, not the optimal goal. To achieve these targets, emergency departments should implement STEMI protocols including:
- Rapid ECG acquisition (within 10 minutes of arrival)
- Immediate cardiology notification
- Single-call catheterization lab activation systems
- Pre-hospital ECG transmission from ambulances when possible
The physiological basis for this time-sensitive approach is straightforward: prolonged coronary artery occlusion leads to progressive, irreversible myocardial necrosis, with the greatest salvage potential occurring within the first 60-120 minutes. Each 30-minute reduction in reperfusion time saves approximately 8 lives per 1,000 patients treated. While 90 minutes remains the widely accepted benchmark, the evidence increasingly suggests that "time is muscle" and efforts should focus on achieving door-to-balloon times closer to 60 minutes for optimal patient outcomes.
In terms of specific guidelines, the American College of Cardiology/American Heart Association (ACC/AHA) recommends a door-to-balloon time of 90 minutes or less for patients with STEMI, with a goal of achieving this time in at least 75% of patients 2, 3, 4, 5, 6. The European Society of Cardiology also recommends a door-to-balloon time of 90 minutes or less, with a goal of achieving this time in at least 90% of patients 1.
Overall, the evidence suggests that achieving a door-to-balloon time of 60 minutes or less is associated with improved outcomes for patients with STEMI, and healthcare systems should strive to achieve this goal whenever possible.
From the Research
Door-to-Balloon Time Comparison
The evidence suggests that a door-to-balloon (D2B) time of 60 minutes is associated with better outcomes compared to a D2B time of 90 minutes.
- A study published in BioMed research international 7 found that patients with a D2B time of less than 60 minutes had better thrombolysis in myocardial infarction (TIMI) flow and lower 30-day mortality rates compared to those with a D2B time of 60-90 minutes.
- Another study published in Clinical research in cardiology 8 found that reducing D2B time to less than 30 minutes was associated with improved clinical outcomes, including lower major cardiac adverse events.
- A study published in the Journal of the American Heart Association 9 found that shortening D2B time was significantly associated with survival benefit, and that reducing D2B time within 45 minutes showed further decreased risk of mortality compared to D2B time greater than 90 minutes.
Comparison of D2B Times
The studies also compared the outcomes of patients with different D2B times.
- The study published in BioMed research international 7 compared the outcomes of patients with D2B times of less than 60 minutes and 60-90 minutes.
- The study published in the Journal of the American Heart Association 9 found that every reduction of D2B time by 30 minutes showed continuous reduction of 1-year mortality.
- The study published in BMJ quality improvement reports 10 found that implementing the Lean Six Sigma methodology resulted in a decreased median door-to-balloon time from 75.9 minutes to 60.1 minutes, and an increase in the percentage of patients who underwent PCI within 90 minutes from 73% to 96%.
Other Factors Affecting Outcomes
Other factors that may affect outcomes in patients with ST-segment elevation myocardial infarction include symptom-to-balloon time and the location of the culprit lesion.
- A study published in the American journal of cardiovascular disease 11 found that symptom-to-balloon time may be a more accurate predictor of outcomes, particularly in patients with left anterior descending (LAD) stenosis.
- The study published in Clinical research in cardiology 8 found that major cardiac adverse events were significantly associated with D2B time greater than 30 minutes, as well as other factors such as age, systolic blood pressure, and multivessel disease.