Door-to-balloon is a time measurement in emergency cardiac care (ECC), specifically in the treatment of ST segment elevation myocardial infarction (or STEMI). The interval starts with the patient's arrival in the emergency department, and ends when a catheter guidewire crosses the culprit lesion in the cardiac cath lab. Because of the adage that "time is muscle", meaning that delays in treating a myocardial infarction increase the likelihood and amount of cardiac muscle damage due to localised hypoxia, ACC/AHA guidelines recommend a door-to-balloon interval of no more than 90 minutes. As of 2006 in the United States, fewer than half of STEMI patients received reperfusion with primary percutaneous coronary intervention (PCI) within the guideline-recommended timeframe. It has become a core quality measure for the Joint Commission on Accreditation of Healthcare Organizations (TJC). Improving door-to-balloon times Door to Balloon (D2B) Initiative The benefit of prompt, expertly performed primary percutaneous coronary intervention over thrombolytic therapy for acute ST elevation myocardial infarction is now well established. Few hospitals can provide PCI within the 90 minute interval, which prompted the American College of Cardiology (ACC) to launch a national Door to Balloon (D2B) Initiative in November 2006. The D2B Alliance seeks to "take the extraordinary performance of a few hospitals and make it the ordinary performance of every hospital." Over 800 hospitals have joined the D2B Alliance as of March 16, 2007. The D2B Alliance advocates six key evidence-based strategies and one optional strategy to help reduce door-to-balloon times: ED physician activates the cath lab Single-call activation system activates the cath lab Cath lab team is available within 20–30 minutes Prompt data feedback Senior management commitment Team based approach (Optional) Prehospital 12 lead ECG activates the cath lab Mission: Lifeline On May 30, 2007, the American Heart Association launched 'Mission: Lifeline', a "community-based initiative aimed at quickly activating the appropriate chain of events critical to opening a blocked artery to the heart that is causing a heart attack." It is seen as complementary to the ACC's D2B Initiative. The program will concentrate on patient education to make the public more aware of the signs of a heart attack and the importance of calling 9-1-1 for emergency medical services (EMS) for transport to the hospital. In addition, the program will attempt to improve the diagnosis of STEMI patients by EMS personnel. According to Alice Jacobs, MD, who led the work group that addressed STEMI systems, when