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Thrombolytic drugs for heart attack
URL of this page: //medlineplus.gov/ency/article/007488.htm

Thrombolytic drugs for heart attack

Small blood vessels called coronary arteries supply oxygen carrying blood to the heart muscle.

  • A heart attack can occur if a blood clot stops the flow of blood through one of these arteries.
  • Unstable angina refers to chest pain and other warning signs that a heart attack may happen soon. It is most often caused by blood clots in the arteries that partially block them.

Some people may be given medicines to break up the clot if the artery is completely blocked.

  • These medicines are called thrombolytics, or clot-busting medicines.
  • They are only given for a type of heart attack, where certain changes are noted on the electrocardiogram (ECG). This type of heart attack is called an ST segment elevation myocardial infarction (STEMI).
  • These medicines should be given as soon as possible after the chest pain first occurs (most often in less than 12 hours).
  • The medicine is given through a vein (IV).
  • Blood thinners taken by mouth may be prescribed later to prevent more clots from forming.

The main risk when receiving clot-busting medicines is bleeding, with the most serious being bleeding in the brain.

Thrombolytic therapy is not safe for people who have:

  • Bleeding inside the head or a stroke
  • Brain abnormalities, such as tumors or poorly-formed blood vessels
  • Had a head injury within the past 3 months
  • A history of using blood thinners or a bleeding disorder
  • Had major surgery, a major injury, or internal bleeding within the past 3 to 4 weeks
  • Peptic ulcer disease
  • Severe high blood pressure

Other treatments to open blocked or narrowed vessels that may be done in place of or after treatment with thrombolytic therapy include:

Alternative Names

Myocardial infarction - thrombolytic; MI - thrombolytic; ST - elevation myocardial infarction; CAD - thrombolytic; Coronary artery disease - thrombolytic; STEMI - thrombolytic

References

Bohula EA, Morrow DA. ST-elevation myocardial infarction: management. In: Libby P, Bonow RO, Mann DL, Tomaselli GF, Bhatt DL, Solomon SD, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 12th ed. Philadelphia, PA: Elsevier; 2022:chap 38.

Byrne RA, Rossello X, Coughlan JJ, et al. 2023 ESC Guidelines for the management of acute coronary syndromes. Eur Heart J. 2023;44(38):3720-3826. PMID: 37622654 pubmed.ncbi.nlm.nih.gov/37622654/.

Lawton JS, Tamis-Holland JE, Bangalore S, et al. 2021 ACC/AHA/SCAI guideline for coronary artery revascularization: executive summary: a report of the American College of Cardiology/American Heart Association Joint Committee on clinical practice guidelines. Circulation. 2022;145(11):e771. PMID: 34882436 pubmed.ncbi.nlm.nih.gov/34882436/.

Rao SV, O'Donoghue ML, Ruel M, et al. 2025 ACC/AHA/ACEP/NAEMSP/SCAI Guideline for the management of patients with acute coronary syndromes: a report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation. 2025;151(13):e771-e862. PMID: 40014670 pubmed.ncbi.nlm.nih.gov/40014670/.

Welt FGP, Fang JC. ST-Elevation acute myocardial infarction and complications of myocardial infarction. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024;chap 58.

Review Date 5/5/2025

Updated by: Michael A. Chen, MD, PhD, Associate Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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