Door-to-Balloon Time in Primary Percutaneous Coronary Intervention

ver the past decade, primary percutaneous coronary intervention (PCI) has emerged as an effective treat- ment strategy for acute ST-segment-elevation myo- cardial infarction (STEMI). Compared with thrombolytic therapy, the benefits of primary PCI include a reduction in the frequency of total stroke and hemorrhagic stroke, a reduction in the frequency of reinfarction, and an increase in the frequency of infarct-related artery patency, resulting in im- proved in-hospital and long-term survival.1 In addition, the availability of primary PCI provides a valid alternative for patients who have contraindications to thrombolytic therapy. Article p 1079 These observations have led many institutions to select primary PCI as the preferred treatment strategy for patients with acute STEMI. In addition, after the publication of several reports on the safety and efficacy of primary PCI in centers without cardiac surgery on site,2,3 several state regu- latory agencies have changed local regulations by allowing primary PCI for acute STEMI in centers without cardiac surgery on site. Thus, it is likely that the next decade will be characterized by further expansion of primary PCI for acute STEMI in hospitals with cardiac catheterization laboratories. As previously shown for thrombolytic therapy, time to treatment also plays a key role in survival with primary PCI. In the Global Use of Strategies to Open Occluded Arteries in Acute Coronary Syndromes (GUSTO-IIb) substudy,4 the lowest 30-day mortality rate was observed in patients under- going primary PCI within 60 minutes from presentation to the emergency room, whereas the highest mortality rate was observed in patients undergoing PCI 90 minutes from presentation (1.0% versus 6.4%). Similar compelling data were reported in an analysis of data from the National Registry of Acute Myocardial Infarction (NRMI). In that analysis, which included 27 080 patients, the lowest mortality rate again was observed in patients undergoing PCI within 60 minutes from presentation, whereas significantly higher mor- tality rates were observed in patients undergoing PCI beyond 120 minutes.5 The importance of door-to-balloon time as a correlate of mortality is further underscored by additional analysis that have shown an inverse relationship between door-to-balloon time and mortality benefit of primary PCI over thrombolysis.6 Thus, given the time dependency of survival in patients with STEMI undergoing primary PCI, the American College of Cardiology and American Heart Asso- ciation guidelines for the management of acute myocardial infarction have established a door-to-balloon time of 90 minutes as a new gold standard for primary PCI.7 Further- more, door-to-balloon time would appear to meet all the criteria for a valid performance measurement. These criteria include a measurement that is meaningful, valid, and reliable; that can account for patient variability; and that is feasible and can be modified by improvements in the healthcare system.8 As such, door-to-balloon time has been adopted as a