“Time is muscle” in reperfusing occluded coronary arteries in acute myocardial infarction

Ian A Scott
Med J Aust 2010; 193 (9): . || doi: 10.5694/j.1326-5377.2010.tb04030.x
Published online: 1 November 2010

There is still room for improvement, both in decreasing delays in, and deciding who is eligible for, reperfusion therapy

In patients with acute ST-segment-elevation myocardial infarction (STEMI), early coronary reperfusion — within 1 to 2 hours of symptom onset — by either thrombolysis or primary percutaneous coronary intervention (PCI) reduces the mortality rate by half. However, this benefit quickly dissipates with further delay in treatment.1 As “time is muscle”, it is the time from symptom onset to reperfusion (or total ischaemic time), rather than the mode of reperfusion, that is the critical determinant of outcome. Hence the imperative to minimise: (i) delay by patients in recognising symptoms as possible myocardial infarction (MI) and seeking medical help; (ii) delay in ambulances responding to calls; (iii) delays in diagnosing STEMI on first medical contact; and (iv) omissions or delays in administering the most appropriate means of reperfusion in eligible patients. In this issue of the Journal, Huynh and colleagues, using data from a prospective Australian registry, report on processes of care and outcomes of 755 patients presenting with suspected STEMI.2

  • Department of Internal Medicine and Clinical Epidemiology, Princess Alexandra Hospital, Brisbane, QLD.


  • 1. Gersh BJ, Stone BW, White HD, Holmes DR. Pharmacological facilitation of primary percutaneous coronary intervention: is the slope of the curve the shape of the future? JAMA 2005; 293: 979-986.
  • 2. Huynh LT, Rankin JR, Tideman P, et al. Reperfusion therapy in the acute management of ST elevation myocardial infarction in Australia. Med J Aust 2010; 193: 496-501. <MJA full text>
  • 3. Taylor DM, Garewal D, Carter M, et al. Factors that impact upon the time to hospital presentation following the onset of chest pain. Emerg Med Australas 2005; 17: 204-211.
  • 4. Finn JC, Bett JHN, Shilton TR, et al on behalf of the National Heart Foundation of Australia Chest Pain Every Minute Counts Working Group. Patient delay in responding to symptoms of possible heart attack: can we reduce time to care? Med J Aust 2007; 187: 293-298. <MJA full text>
  • 5. Lambert L, Brown K, Segal E, et al. Association between timeliness of reperfusion therapy and clinical outcomes in ST-elevation myocardial infarction. JAMA 2010; 303: 2148-2155.
  • 6. Sexton PT, Sexton T-LH. Excess coronary mortality among Australian men and women living outside the capital city statistical divisions. Med J Aust 2000; 172: 370-374. <MJA full text>
  • 7. Eagle KA, Goodman SG, Avezum A, et al for the GRACE Investigators. Practice variation and missed opportunities for reperfusion in ST-segment-elevation myocardial infarction: findings from the Global Registry of Acute Coronary Events (GRACE). Lancet 2002; 359: 373-377.
  • 8. Gharacholou SM, Alexander KP, Chen AY, et al. Implications and reasons for the lack of use of reperfusion therapy in patients with ST-segment elevation myocardial infarction: Findings from the CRUSADE initiative. Am Heart J 2010; 159: 757-763.
  • 9. Koeth O, Zahn R, Gitt AK, et al for the Maximal Individual Therapy in Acute Myocardial Infarction Plus (MITRA Plus) Study Group. Clinical benefit of early reperfusion therapy in patients with ST-elevation myocardial infarction usually excluded from randomized clinical trials (Results from the Maximal Individual Therapy in Acute Myocardial Infarction Plus [MITRA Plus] Registry). Am J Cardiol 2009; 104: 1074-1077.
  • 10. Spencer FA, Montalescot G, Fox KAA, et al for the Global Registry of Acute Coronary Events (GRACE) Investigators. Delay to reperfusion in patients with acute myocardial infarction presenting to acute care hospitals; an international perspective. Eur Heart J 2010; 31: 1328-1336.
  • 11. Terkelsen CJ, Soronsen JT, Maeng M, et al. System delay and mortality among patients with STEMI treated with primary percutaneous coronary intervention. JAMA 2010; 304: 763-771.
  • 12. Acute Coronary Syndrome Guidelines Working Group. Guidelines for the management of acute coronary syndromes 2006. Med J Aust 2006; 184 (8 Suppl): S1-S32. <MJA full text>
  • 13. Danchin N, Coste P, Ferrieres J, et al. Comparison of thrombolysis followed by broad use of percutaneous coronary intervention with primary percutaneous coronary intervention for ST-elevation acute myocardial infarction. Data from the French registry on acute ST-elevation myocardial infarction (FAST-Mi). Circulation 2008; 118: 268-276.
  • 14. Harper RW, Lefkovits J. Prehospital thrombolysis followed by early angiography and percutaneous coronary intervention where appropriate – an underused strategy for the management of STEMI. Med J Aust 2010; 193: 234-237. <MJA full text>
  • 15. De Luca G, Cassetti E, Marino P. Percutaneous coronary intervention-related time delay, patient’s risk profile, and survival benefits of primary angioplasty vs lytic therapy in ST-segment elevation myocardial infarction. Am J Emerg Med 2009; 27: 712-719.
  • 16. Pinto DS, Kirtane AJ, Nallamothu BK, et al. Hospital delays in reperfusion for ST-elevation myocardial infarction: implications when selecting a reperfusion strategy. Circulation 2006; 114: 2019-2025.
  • 17. Bradley EH, Herrin J, Wang Y, et al. Strategies for reducing the door-to-balloon time in acute myocardial infarction. N Engl J Med 2006; 355: 2308-2320.
  • 18. Ting HH, Rihal CS, Gersh BJ, et al. Regional systems of care to optimize timeliness of reperfusion therapy for ST-elevation myocardial infarction. The Mayo Clinic STEMI Protocol. Circulation 2007; 116: 729-736.
  • 19. Willson AB, Mountain D, Jeffers JM, et al. Door-to-balloon times are reduced in ST-elevation myocardial infarction by emergency physician activation of the cardiac catheterisation laboratory and immediate patient transfer. Med J Aust 2010; 193: 207-212. <MJA full text>


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