Pre-hospital reperfusion therapy: a strategy to improve therapeutic outcome in patients with ST-elevation myocardial infarction.

Therapy of acute ST-elevation myocardial infarction (STEMI) has undergone dramatic improvements during the past three decades, and in-hospital and 30-day mortality rates have tremendously decreased from . 15–20% in the pre-thrombolytic area to 8–10% using fibrin-non-specific agents, to 6–8% using fibrin-specific thrombolytic agents, and down to 4.5% by the use of primary percutaneous coronary intervention (PPCI) in controlled trials by experienced centres under optimal trial conditions (Figure 1 ). However, translation of these results, obtained in the setting of controlled trials, into the real world, is different, as demonstrated by the results of registries. Registry data show mortality rates of . 20% in patients who do not undergo reperfusion therapy within 12 h, of 10% in thrombolysed patients, and of up to 6–8% in patients treated by PPCI. The overall success rate depends not only on the individual patient’s risk (high-risk patients, e.g. patients in shock, or the elderly, usually have not been included into controlled trials) but also on the optimal organization and the use of the available reperfusion strategies. Although thrombolytic therapy concerns remain with suboptimal patency, early reocclusion, and failure of myocardial reperfusion at the microcirculatory level, suboptimal results with PPCI are related to the lack of operator experience and excessive treatment delays. The mean door-toballoon time in registries and the real world often exceeds 110–120 min, depending on the time of the day the patient is presenting and the availability of a cath lab and experienced interventionalists. Time to reperfusion plays an important role for myocardial salvage, and the concept of the ‘golden hour’, i.e. the optimal time window for initiation of treatment (within 1 h from the onset of pain), appears now to be applicable to all patients, including those treated by pharmacological reperfusion therapies. At present, PPCI is only available on an average for 15–20% of patients suffering from STEMI in the western world. Exceptions are well-developed areas where a 24 h availability of catheter facilities has been organized and the PPCI rate in STEMI patients can be up to . 80%. Therefore, in most regions in the world in general, and in Europe in particular, thrombolytic therapy is still the fastest and best accessible reperfusion treatment for most patients presenting with acute STEMI, as indicated in the international guidelines. In addition, thrombolysis and PPCI are not mutually exclusive therapies, and attempts at combining them are ongoing. Therefore, the main questions today are not whether percutaneous coronary intervention (PCI) is superior to thrombolytic therapy, but (i) what kind of reperfusion therapy is immediately available, dependent on the local situation; (ii) how to reduce time from onset of symptoms to reperfusion; and (iii) whether the combination of both strategies, immediate medical reperfusion followed by PCI (‘facilitated PCI’), will further improve the therapy of STEMI. Another important question is to elucidate which patients should be transferred to tertiary care units for primary PCI and to determine the optimal medical therapy during transport. These aspects are the focus of the this article. However, it should be realized that the most important goal today is still to offer more patients with STEMI any type of reperfusion therapy, because recent investigations have shown that almost one-third of eligible patients is not given reperfusion therapy at all. It was not the intent of the authors to make specific recommendations, given the absence of formal guidelines and need for more data. However, the current report should increase the awareness for the need and formulation of specific guidelines concerning pre-hospital reperfusion strategies in the near future. The report is based on the