Professor Frans Van de Werf (Leuven, Belgium), chairperson of the Task Force, describes the guidelines as “important” and says their broad uptake and adoption would make a “huge difference” to heart attack survival rates.
The new guidelines cover management of a common type of classical heart attack known as STEMI (ST-segment elevation acute myocardial infarction), a reference to its appearance on an ECG. Around one-third of all acute coronary events are diagnosed as STEMI.
Although precise numbers are missing, it is likely that 30-50 per cent of victims of heart attack die before reaching the hospital, most of them in the first hours after the onset of symptoms. While this fatality rate has remained fairly constant in recent years, survival rates in hospital have markedly improved – from a rate of 75 per cent in the 1960s to around 95 per cent today. The introduction of coronary care units, new techniques of coronary intervention and treatments to dissolve blood clots (thrombolysis) have all improved in-hospital care.
The principal features of the new guidelines – and the major changes since the previous edition of 2003 – relate to emergency systems and a speedy emphasis on reperfusion therapy, performed either by “percutaneous coronary interventions” (PCI, with balloon angioplasty and stent) or thrombolysis treatment (with clot-dissolving drugs).
Key to management, say the guidelines, is early diagnosis and risk assessment after “first medical contact” (FMC).
* Primary PCI is the “preferred treatment” if available within two hours of FMC.
* If PCI is not possible within two hours, pre- or in-hospital thrombolysis should be performed as soon as possible after FMC (and within 30 minutes at the latest).
The guidelines state: “Primary PCI is deﬁned as angioplasty and/or stenting without prior or concomitant thrombolytic therapy, and is the preferred therapeutic option when it can be performed expeditiously by an experienced team.” The shorter the delay, the better the outcome – and FMC-to-balloon should be within two hours “in all cases”. However, the guidelines add that only hospitals with an established interventional cardiology programme – 24/7 - should use primary PCI.
The guidelines also recommend that most patients following successful thrombolysis should be routinely referred for angiography, a technique whereby the condition of the coronary arteries and heart muscle can be assessed and long-term risks and treatments determined.
Professor Van de Werf concedes that not all hospitals nor all regions have the emergency networks or PCI facilities recommended in the guidelines. Indeed, current registry data suggest that around 20-30 per cent of all STEMI patients in Europe still receive no reperfusion therapy. However, adherence to the guidelines, he suggests, could “dramatically” improve STEMI patient survival.
The ambulance is also crucial to improving survival rates – for speedy transfer, defibrillation if needed, diagnosis by ECG, early thrombolysis therapy if needed, and early alert to the hospital. The guidelines recommend that an ambulance should be available within 15 minutes of a call and all should be equipped with 12-lead ECG. Also recommended is that the techniques of basic life support should be part of the school curriculum.