2012 ESC STEMI guidelines and reperfusion therapy

To cite: Terkelsen CJ, Pinto DS, Thiele H, et al. Heart 2013;99:1154–1156. The 2012 European Society of Cardiology (ESC) ST-Elevation Myocardial Infarction (STEMI) guideline acknowledges that STEMI patients should receive reperfusion therapy as soon as possible, and that prehospital fibrinolysis or field-triage directly to Primary Percutaneous Coronary Intervention (PPCI) centres is the preferred reperfusion strategy. However, when recommending fibrinolytic therapy (FT) within 30 min from First Medical Contact (FMC), if PPCI cannot be performed ‘within 60 min of FMC in patients presenting early, with a large amount of myocardium at risk’, the guidelines imply that only 30 min extra may be expended to perform PPCI instead of administering FT (‘PCI-related delay’) (figure 1). Throughout the years, successive guidelines have mistakenly equated ‘PCI-related delay’ and ‘FMC to PPCI’ (the total delay from FMC to PPCI) (figure 1). This error persists in the recently updated ESC guideline. Clarification of this distinction is of paramount importance because of the suggested reduction in the ‘window of opportunity for PPCI’, a suggestion not clearly supported by evidence, which has significant public health implications. In paragraph 3.5.2, the ESC STEMI guideline references a registry analysis from the National Registry of Myocardial Infarction (NRMI), concluding: ‘primary PCI (wire passage) should be performed within 90 min after FMC in all cases. In patients presenting early, with a large amount of myocardium at risk, the delay should be shorter (<60 min).’ The NRMI reference is also listed in paragraph 3.4.1 in the ESC STEMI guideline when recommending the acceptable ‘FMC-to-PCI’ delay of only 60 min in early incomers with anterior infarction. However, this study describes ‘PCI-related delay’, that is, the theoretical extra delay that may be spent to perform PPCI over FT (figure 1). The NRMI manuscript by Pinto et al. does not describe ‘FMC-to-PCI’ delay in the cohorts evaluated since timing of Emergency Medical Service (EMS) evaluation was imprecise. The only delay data available were the interval ‘Door-to-balloon (D2B)’ delay, which was 116 min when calculated as a weighted mean (table 1). Given the fact that ‘FMC-to-PCI’ is considerably longer than D2B delay among patients transported by EMS (figure 1), the ‘FMC-to-PCI’ delay is likely to have been considerably longer than 120 min (table 1). Consequently, these data cannot be applied recommendations regarding the optimal time to ‘FMC to PCI’ or to support a recommendation ‘of a systems goal of FMC to PCI of 60 min.’ It would appear that the 2012 STEMI guideline authors, when compiling the overwhelming amount of scientific data, have either intended to use a different reference or misinterpreted the findings from Pinto et al’s original work. We are not aware of supportive data that would justify the current STEMI guideline recommendations to consider fibrinolysis within 30 min of FMC when PPCI cannot be performed within 60 min of FMC. There have been several other studies addressing the optimal ‘PCI-related delay’. The initial study by Pinto and colleagues was limited by the fact that optimal FT (fibrin-specific drugs) was compared with a less-than-optimal PPCI strategy (PPCI centres performing only a mean of 20 PPCI procedures a year). A later analysis by Pinto and colleagues found an acceptable ‘PCI-related delay’ of approximately 120 min without any excessive mortality in PPCI-treated patients with anterior infarction or short symptom duration, even at a PCI-related delay of approximately 120 min. While the magnitude of survival difference between PPCI and FT decreased as delay to PCI increased, at no point did mortality for PPCI exceed that with FT. These findings are concordant with the previous findings by Boersma and colleagues that were based on individual data from studies comparing FT with PPCI. Swedish registry data indicate a comparable outcome from PPCI and FT, even with a PCI-related delay of 240 min, and observations from both the French FAST-MI registry and the Vienna registry report comparable outcomes for patients treated with FT and PPCI with a PCI-related delay of 90 min. The ESC STEMI guideline also relies upon analysis of the Comparison of Angioplasty and Pre-hospital Thrombolysis in Acute Myocardial Infarction (CAPTIM) trial when recommending a ‘FMC-to-PPCI’ delay of 60 min. This nonprespecified subgroup analysis, based on 460 patients, claimed a lower mortality in patients randomised to FT versus PPCI among subjects presenting early. However, this finding did not reach statistical significance. A much larger meta-analysis including individual data from 6763 patients demonstrated superiority of PPCI over FT, in early as well as late incomers. This finding was also confirmed in the Swedish registry data. It seems that the aforementioned subgroup analysis from CAPTIM was weighted too heavily. Furthermore, findings from the CAPTIM substudy offer little value in substantiating a recommendation of ‘FMC to PPCI’ of <60 min, Open Access Scan to access more free content