The new ESC 2020 guidelines

The annual ESC congress recorded four new or updated guidelines. We report some key points related to the management of non-ST segment elevation acute coronary syndromes.

A brief overview of the new ESC guidelines for the management of NSTEMI heart attacks

The annual congress of the European Society of Cardiology provided a platform for the presentation of more than 4,000 clinical abstracts by scientists from around the world. It also recorded the publication of four new or updated guidelines. We report some key points of the new guidelines for the management of non-ST segment elevation acute coronary syndromes.

For the first time ever, the annual ESC Scientific Congress was held as a "The Digital Experience" due to the COVID-19 pandemic. However, this did not dampen the enthusiasm around the congress, which this year recorded a record number of participants (more than 100,000 on the first day) and perhaps represented a real digital revolution in cardiovascular learning and sharing.

In 2020, leaving aside COVID-19, cardiovascular diseases, particularly ischemic heart disease, still remain the leading cause of death in the world. The ESC's mission is to reduce the global impact of cardiovascular disease. Among the various actions conducted by the ESC is the publication of clinical practice guidelines that provide recommendations for optimizing treatment based on the best evidence. New guidelines for the management of acute coronary syndromes in non-ST segment elevation patients were presented during the conference, among others.

What will be the impact of these new guidelines in current medical practice?

The majority of patients with ischemic heart disease present an acute coronary syndrome without ST elevation (NSTE-ACS). The management of NSTE-ACS begins with the correct diagnosis, the appropriate and timely initiation of appropriate therapy, the execution of hemodynamic procedures, and secondary preventive care. 5 years after the latest ESC guidelines for NSTE-ACS, which novelties in the guidelines will influence or change clinical practice? First of all, the new ESC 2020 guidelines have introduced new sections on the following important topics:

The new ESC 2020 guidelines also contain new or updated recommendations on:

Clinical evaluation: We always go back to the roots

The COVID-19 pandemic has caused hospitalizations for myocardial infarction to halve worldwide, probably, among other reasons, for fear of going to a hospital and being infected. However, NSTE-ACS is a life-threatening condition, and therefore calling for help when symptoms occur is essential to save lives and avoid future complications, including heart failure.

The new ESC guidelines have emphasized the importance of evaluating clinical presentation and explain that: Typical chest pain is characterized by a retrosternal pain sensation, pressure or heaviness ('angina') radiating to the left arm, both arms or the right arm, neck, or jaw, which can be intermittent (usually lasting several minutes) or persistent. Additional symptoms such as sweating, nausea, epigastric pain, dyspnea, and syncope may be present. Atypical presentations include isolated epigastric pain, indigestion-like symptoms, and isolated dyspnea or fatigue. Atypical disorders are most often observed in the elderly, women, and patients with diabetes, chronic kidney disease, or dementia. The exacerbation of physical exertion symptoms and their relief at rest increase the likelihood of myocardial ischemia.

15 key points of the new ESC guidelines

  1. The pathological correlate for ACS in patients who do not have persistent ST-segment elevation (NSTE-ACS) at the myocardial level is cardiomyocytic necrosis, measured by troponin levels, or, less frequently, myocardial ischemia without cellular damage (unstable angina). In general, individuals with unstable angina have a substantially lower risk of death and benefit less from an aggressive pharmacological approach and invasive procedures.
     
  2. Measurement of high-sensitivity cardiac troponin dosage (hs-cTn) is more recommended than a less sensitive dosage, as it provides greater diagnostic accuracy at the same low cost. In fact, many heart diseases other than myocardial infarction also cause cardiomyocytic lesions and, therefore, increases in cardiac troponins (cTn).
     
  3. Other biomarkers may have clinical relevance in specific contexts when used in combination with non highly sensitive T/I cardiac troponins. CK-MB levels decrease rapidly after a heart attack, so their measurement can provide added value for the detection of a new event. Routine dosing of copeptin to rule out a heart attack early is recommended in the rare situation where it is not possible to dose hs-cTn.
     
  4. The time interval between the first and second assessment of troponin can be reduced with the use of hs-cTn due to the increased sensitivity and diagnostic accuracy for the detection of myocardial infarction. It is recommended to use either the 0 h/1 h algorithm (best option, blood sampling at 0 h and 1 h) or the 0 h/2 h algorithm (second option, blood sampling at 0 h and 2 h). Used in combination with clinical and electrocardiographic (ECG) results, the 0 h/1 h and 0 h/2 h algorithm allows the identification of appropriate candidates for early discharge and outpatient management.
     
  5. Four clinical variables significantly influence hs-cTn concentrations, including age (differences between very young and "healthy" very old individuals up to 300%), renal dysfunction (differences between very high and very low eGFR up to 300%), the onset of chest pain (>300%) and sex (~40%).
     
  6. Initial troponin levels add prognostic information in terms of short and long-term mortality to clinical variables and ECG. The higher the levels of hs-cTn, the greater the risk of death. Serum creatinine and eGFR should also be measured in all patients with NSTE-ACS because they influence prognosis and are key elements of the GRACE risk score, the result of which is more reliable than the physician's (subjective) assessment to predict the occurrence of death or myocardial infarction. In addition, natriuretic peptides can provide additional prognostic information.
     
  7. The use of the Academic Research Consortium for High Bleeding Risk (ARC-HBR) assessment is a pragmatic approach to assessing hemorrhagic risk. It includes the most recent studies conducted in patients at high risk of bleeding who had previously been excluded from clinical trials of duration or intensity of Dual Antiplatelet Therapy (DAPT). The PRECISE-DAPT score can be used to guide and inform decision making on the duration of DAPT with a modest predictive value for major bleedings (however, the benefit to patient outcomes remains unclear).
     
  8. Clinical evaluation can direct to non-invasive or invasive imaging examinations even after the exclusion of myocardial infarction. Coronary Computed Tomography Angiography (CCTA) may be an option in patients with a low or modest clinical likelihood of unstable angina, as a normal outcome excludes coronary artery disease (CAD). CCTA has a high negative predictive value to exclude ACS (excluding CAD) and predicts an excellent outcome in patients presenting to the emergency room with a low or modest likelihood of ACS and normal CCTA. Stress imaging using cardiac MRI, echocardiography, or nuclear imaging may also be a risk-based option.
     
  9. A routine early invasive approach within 24 hours of admission is recommended for NSTEMI based on hs-cTn measurements, GRACE risk score >140, and dynamic ST-segment changes, as it improves major adverse cardiac events and possibly early survival. Immediate invasive angiography is required in highly unstable patients based on hemodynamic status, arrhythmias, acute heart failure, or persistent chest pain. In all other clinical presentations, a selective invasive approach may be performed according to non-invasive test results or clinical risk assessment.
     
  10. The main technical aspects of percutaneous coronary intervention (PCI) intervention in NSTE-ACS patients do not differ from the invasive procedure and revascularization strategies for other CAD presentations. Radial access is recommended for NSTE-ACS patients undergoing an invasive procedure with or without PCI. Because NSTE-ACS patients frequently have a multi-vascular disease, the timing and completeness of revascularization should be decided based on the functional relevance of all stenosis, age, general patient condition, comorbidities, and left ventricular function.
     
  11. Myocardial infarction with non-obstructive coronary arteries  (MINOCA) represents a heterogeneous group of underlying causes that may involve both coronary and noncoronary pathological conditions, including cardiac and extracardiac disorders. Myocarditis and Takotsubo syndrome are excluded by consensus. CMR (cardiovascular magnetic resonance) is one of the key diagnostic tools, as it identifies the underlying cause in >85% of patients and the appropriate subsequent treatment.
     
  12. SCAD is a non-atherosclerotic, non-traumatic or iatrogenic detachment of coronary arteries secondary to vascular hemorrhage or intimate tearing, and represents up to 4% of all ACS, but the incidence is much higher (22-35% of ACS) in women under 60 years of age. Intracoronary imaging is very useful for the diagnosis and orientation of treatment. Medical treatment is not well defined.
     
  13. Routine pre-treatment with P2Y12 platelet receptor inhibitors (ticlopidine, clopidogrel, prasugrel, and ticagrelor) is not indicated in NSTE-ACS patients whose coronary anatomy is unknown and early invasive management is expected due to lack of safe benefit. However, it may be considered in selected cases, and based on the patient's bleeding risk.
     
  14. DAPT therapy, represented by a potent P2Y12 receptor inhibitor in addition to aspirin, is generally recommended for 12 months, regardless of the type of stent, unless there are contraindications. However, new scenarios have been implemented. The duration of DAPT can be shortened (<12 months), extended (>12 months), or modified. These decisions depend on individual clinical judgment driven by the patient's ischemic and hemorrhagic risk, the occurrence of adverse events, comorbidities, other ongoing therapies, and the availability of the respective drugs.
     
  15. In at least 6-8% of patients undergoing PCI, long-term oral anticoagulant therapy is indicated. In general, new oral anticoagulants (NOAC, New Oral Anticoagulants) are preferable to VKA (Vitamin-K antagonists) in terms of safety when patients are suitable. Dual antithrombotic therapy with NOAC at the recommended dose for stroke prevention and single antiplatelet therapy (preferably clopidogrel, chosen in >90% of cases in available studies) is recommended as the default strategy up to 12 months after a short period - up to 1 week - of triple antithrombotic therapy (with NOAC and DAPT). TAT (triple antithrombotic therapy) can be prolonged up to 1 month when the ischemic risk exceeds the hemorrhagic risk.

Sources: 
1. Jean-Philippe Collet, Holger Thiele, Emanuele Barbato, Olivier Barthélémy, Johann Bauersachs, Deepak L Bhatt, Paul Dendale, Maria Dorobantu, Thor Edvardsen, Thierry Folliguet, Chris P Gale, Martine Gilard, Alexander Jobs, Peter Jüni, Ekaterini Lambrinou, Basil S Lewis, Julinda Mehilli, Emanuele Meliga, Béla Merkely, Christian Mueller, Marco Roffi, Frans H Rutten, Dirk Sibbing, George C M Siontis, ESC Scientific Document Group, 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), European Heart Journal, ehaa575, https://doi.org/10.1093/eurheartj/ehaa575
2. Mukherjee D. 2020 ESC NSTE-ACS Guidelines: Key Points. American College of Cardiology Foundation. Aug 29, 2020
3. Kunadian V. What’s new in the 2020 ESC Clinical Practice Guideline on the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation (NSTE-ACS)?. PCR Online. 29 Aug 2020