2015 ESC guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation: comments from the Dutch ACS working group

The 2015 ESC guidelines for the management of acute coronary syndromes (ACS) in patients presenting without persistent ST-segment elevation were presented at the European Society of Cardiology (ESC) Conference 2015 in London and published in the European Heart Journal [1]. Compared with the 2011 version, multiple recommendations have been implemented which we discuss from a Dutch perspective.

The introduction of high-sensitive cardiac troponin has led to a better detection and quantification of myocardial injury. Both the absolute value and change in troponin over time provide information on cardiomyocyte injury, and several studies have assessed the sensitivity and specificity of these measurements [2]. In the 2015 guidelines, algorithms are presented for rule-in and rule-out of non-ST-elevation myocardial infarction (NSTEMI) with the use of high-sensitive cardiac troponin (Figs. 1 and 2). We advise to use these high-sensitive troponin assays and incorporate the aforementioned algorithms in daily practice in the Netherlands.

When NSTE-ACS is diagnosed, there is an indication for treatment with dual platelet aggregation inhibitors (acetylsalicylic acid and a P2Y12 inhibitor). For patients managed conservatively, the 2015 guidelines advise to use ticagrelor over clopidogrel. While the 2011 ESC guidelines recommended starting dual antiplatelet therapy (DAPT) as soon as possible before coronary angiography [3], the most recent guidelines are less strict suggesting to initiate the P2Y12 inhibitor either before or after coronary angiography. This change is based on the results of the ACCOAST study, in which patients with NSTE-ACS, who were scheduled to undergo catheterisation, were randomised to pretreatment with prasugrel or placebo [4]. Pretreatment with prasugrel did not reduce the rate of major ischaemic events up to 30 days but increased the rate of major bleeding complications. Until more evidence is available, the current guidelines thus provide the opportunity to individualise treatment and postpone the initiation of P2Y12 inhibition in patients with known coronary anatomy or electrocardiographic changes suggesting three-vessel disease or left-main disease and therefore a suspected indication for early coronary artery bypass surgery (CABG). In patients with a low to intermediate bleeding risk and a high probability of subsequent percutaneous coronary intervention (PCI), pretreatment with clopidogrel or ticagrelor might be useful.

A subset of patients with NSTE-ACS have indications for long-term (non-vitamin K) oral anticoagulation ([N]OAC) such as atrial fibrillation or mechanical heart valves. In combination with ACS, regardless of the performance of PCI, there is an indication for triple therapy (DAPT with [N]OAC). Long-term triple therapy is, however, associated with increased bleeding outcomes [5], and a subsequent increased mortality. Therefore, individualised treatment is necessary in which the ischaemic risk is weighed against the bleeding risk. The current ESC guidelines provide a useful approach in which both the ischaemic and the bleeding risk are taken into account (Fig. 3). In medically managed patients or patients undergoing CABG, a combination of single antiplatelet aggregation therapy and (N)OAC is recommended. If the NSTE-ACS patient undergoes PCI, one or six months of triple therapy is recommended depending on the bleeding risk. After one or six months, a combination of single antiplatelet aggregation therapy and (N)OAC is continued. The Dutch WOEST trial has demonstrated that dual therapy after PCI might be adequate for the prevention of ischaemic events, with a reduction of bleeding events [6]. Combinations of (N)OAC with the stronger platelet aggregation drugs prasugrel or ticagrelor is discouraged because of the excessive bleeding risk. We advise to follow the treatment algorithm as shown in Fig. 3, and emphasise to individualise the treatment based on the ischaemic and bleeding risk. Furthermore, there is room for improvement with regards to the communication between the interventional cardiologist performing PCI and the treating physician, especially regarding ischaemic and bleeding risk. Complex coronary interventions, such as multiple stent constructions and the placement of bioabsorbable vascular scaffolds, might require more intensive and longer treatment with DAPT also when combined with (N)OAC. Otherwise, monotherapy with (N)OAC is recommended after 1 year.

Comparable with the 2011 ESC guidelines, the current guidelines mention that the decision for and timing of invasive coronary angiography is based on risk stratification and the assessment of the risks related to the procedure (Fig. 4).