2020 ESC Guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation: The Task Force for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation of the European Society of Cardiology (ESC) 

Jean-Philippe Collet, Holger Thiele, Emanuele Barbato, Olivier Barthélémy, Johann Bauersachs, Deepak L Bhatt, Paul Dendale, Maria Dorobantu, Thor Edvardsen, Thierry Folliguet… Show moreEuropean Heart Journal; ehaa575, https://doi.org/10.1093/eurheartj/ehaa575

Published: 29 August 2020

Key Messages

• Diagnosis. Chest discomfort without persistent ST-segment elevation (NSTE-ACS) is the leading symptom initiating the diagnostic and therapeutic cascade. The pathological correlate at the myocardial level is cardiomyocyte necrosis, measured by troponin release, or, less frequently, myocardial ischaemia without cell damage (unstable angina). Individuals with unstable angina have a substantially lower risk of death and derive less benefit from an aggressive pharmacological and invasive approach.
• Troponin assays. High-sensitivity troponin assays measurements are recommended over less sensitive ones, as they provide higher diagnostic accuracy at identical low cost. It should be noted that many cardiac pathologies other than MI also result in cardiomyocyte injury and, therefore, cardiac troponin elevations.
• Other biomarkers. Other biomarkers may have clinical relevance in specific clinical settings when used in combination with non hs-cTn T/I. CK-MB shows a more rapid decline after MI and may provide added value for detection of early reinfarction. The routine use of copeptin as an additional biomarker for the early rule-out of MI is recommended in the increasingly uncommon setting where hs-cTn assays are not available.
• Rapid ‘rule-in’ and ‘rule-out’ algorithms. Due to the higher sensitivity and diagnostic accuracy for the detection of MI at presentation, the time interval to the second cTn assessment can be shortened with the use of hs-cTn assays. It is recommended to use the 0 h/1 h algorithm (best option, blood draw at 0 h and 1 h) or the 0 h/2 h algorithm (second-best option, blood draw at 0 h and 2 h). Optimal thresholds for rule-out and rule-in were selected to allow for a minimal sensitivity and NPV of 99% and a minimal PPV of 70%. Used in conjunction with clinical and ECG findings, the 0 h/1 h and 0 h/2 h algorithm allows the identification of appropriate candidates for early discharge and outpatient management.
• Confounders of hs-cTn. Beyond the presence or absence of MI, four clinical variables affect hs-cTn concentrations. The effect of age (differences in concentration between healthy very young vs. ‘healthy’ very old individuals up to 300%), renal dysfunction (differences in concentration between otherwise healthy patients with very high vs. very low eGFR up to 300%), and chest pain onset (>300%) is substantial, and modest for sex (≈40%).
• Ischaemic risk assessment. Initial cTn levels add prognostic information in terms of short- and long-term mortality to clinical and ECG variables. The higher the hs-cTn levels, the greater the risk of death. Serum creatinine and eGFR should also be determined in all patients with NSTE-ACS because they affect prognosis and are key elements of the GRACE risk score, which assessment is superior to (subjective) physician assessment for the occurrence of death or MI. Natriuretic peptides may provide incremental prognostic information and may help in risk stratification.
• Bleeding risk assessment. ARC-HBR is a pragmatic approach that includes the most recent trials performed in HBR patients, who were previously excluded from clinical trials of DAPT duration or intensity. The PRECISE-DAPT score may be used to guide and inform decision making on DAPT duration with a modest predictive value for major bleeding. Their value in improving patient outcomes remains unclear.
• Non-invasive imaging. Even after the rule-out of MI, elective non-invasive or invasive imaging may be indicated according to clinical assessment. CCTA may be an option in patients with low-to-modest clinical likelihood of unstable angina as a normal scan excludes CAD. CCTA has a high NPV to exclude ACS (by excluding CAD) and an excellent outcome in patients presenting to the emergency department with low-to-intermediate pre-test probability for ACS and a normal CCTA. In addition, upfront imaging with CCTA reduces the need for ICA in high risk patients. Stress imaging by cardiac magnetic resonance imaging, stress echocardiography, or nuclear imaging may also be an option based on risk assessment.
• Risk stratification for an invasive approach. An early routine invasive approach within 24 h of admission is recommended for NSTEMI based on hs-cTn measurements, GRACE risk score >140, and dynamic new, or presumably new, ST-segment changes as it improves major adverse cardiac events and possibly early survival. Immediate invasive angiography is required in highly unstable patients according to hemodynamic status, arrythmias, acute heart failure, or persistent chest pain. In all other clinical presentation, a selective invasive approach may be performed according to non-invasive testing or clinical risk assessment.
• Revascularization strategies. The principal technical aspects of PCI in NSTE-ACS patients do not differ from the invasive assessment and revascularization strategies for other manifestations of CAD. Radial access is recommended as the preferred approach in NSTE-ACS patients undergoing invasive assessment with or without PCI. Multivessel disease is frequent in NSTE-ACS, timing and completeness of revascularization should be decided according to functional relevance of all stenoses, age, general patient condition, comorbidities, and left ventricular function.
• Myocardial infarction with non-obstructive coronary arteries. MINOCA incorporates a heterogeneous group of underlying causes that may involve both coronary and non-coronary pathological conditions, with the latter including cardiac and extra-cardiac disorders. It excludes by consensus myocarditis and Takotsubo syndrome. Cardiac magnetic resonance imaging is one of the key diagnostic tools as it identifies the underlying cause in more than 85% of patients and the subsequent appropriate treatment.
• Spontaneous coronary artery dissection. Defined as a non-atherosclerotic, non-traumatic, or iatrogenic separation of the coronary arterial tunics secondary to vasa vasorum hemorrhage or intimal tear, it accounts for up to 4% of all ACS, but the incidence is reported to be much higher (22–35% of ACS) in women <60 years of age. Intracoronary imaging is very useful for the diagnosis and treatment orientation. Medical treatment remains to be established.
• Pre-treatment with P2Y₁₂ receptor inhibitors. Routine pre-treatment with a P2Y₁₂ receptor inhibitor in NSTE-ACS patients in whom coronary anatomy is not known and an early invasive management is planned is not recommended given the lack of established benefit. However, it may be considered in selected cases and according to the bleeding risk of the patient.
• Post-treatment antiplatelet therapy. DAPT consisting of a potent P2Y₁₂ receptor inhibitor in addition to aspirin is generally recommended for 12 months, irrespective of the stent type, unless there are contraindications. New scenarios have been implemented. DAPT duration can be shortened (<12 months), extended (>12 months), or modified by switching DAPT or de-escalation. These decisions depend on individual clinical judgment being driven by the patient’s ischaemic and bleeding risk, the occurrence of adverse events, comorbidities, co-medications, and the availability of the respective drugs.
• Triple antithrombotic therapy. In at least 6–8% of patients undergoing PCI, long-term oral anticoagulation is indicated and should be continued. NOACs are preferred over VKAs in terms of safety when patients are eligible. DAT with a NOAC at the recommended dose for stroke prevention and SAPT (preferably clopidogrel, chosen in more than 90% of cases in available trials) is recommended as the default strategy up to 12 months after a short period up to 1 week of TAT (with NOAC and DAPT). TAT may be prolonged up to 1 month when the ischaemic risk outweighs the bleeding risk.