The 2024 European Society of Cardiology (ESC) Guidelines on the management of chronic coronary syndromes (CCS) include a focus on both larger and smaller blood vessels of the heart; new models to estimate chances of blocked large arteries (so-called obstructive coronary artery disease); optimal selection and sequence of tests; drugs and interventions to prevent disease complications and improve symptoms, and the fundamental role of patient involvement.

“The new guidelines prompt cardiologists to rethink chronic coronary syndromes as caused not only by blockages in large arteries but also by dysfunction of smaller vessels (microcirculation),” explains Guidelines co-chair Professor Christiaan Vrints, Antwerp University Hospital and University of Antwerp, Antwerp, Belgium.

“Over half of individuals suspected of CCS may have angina/ischemia with nonobstructive coronary arteries (ANOCA/INOCA) caused by coronary artery spasm or microcirculatory dysfunction. This condition is often missed—on average it is diagnosed only after seeing three cardiologists—because the usual tests don’t work well to detect it. Patients may suffer severely from persistent symptoms that can cause repeated hospitalizations and even heart failure.”

Published in the European Heart Journal, the guidelines highlight that persistently symptomatic patients with suspected ANOCA/INOCA who do not respond to guideline-derived medical therapy should undergo invasive coronary functional testing to determine underlying endotypes and to guide appropriate medical therapy.

A further new recommendation strongly endorsed by the guidelines is the use of the risk factor-weighted clinical likelihood model to estimate the pre-test likelihood of obstructive coronary artery disease. With this new prediction model, around half of individuals assessed for chest pain have a very low likelihood of large artery blockage (=5%), and in these patients further testing should be deferred, whereas with the ESC 2019 model, only 19% were identified as having a very low likelihood. This prediction model has been developed and validated in Western countries (northern EU, UK, and US). The results may vary depending on region, race, cultural differences, and healthcare system organisations.

For individuals with symptoms suggestive of chronic coronary syndrome who have a low to moderate (>5%–50%) likelihood of obstructive coronary artery disease based on symptoms, age, sex and risk factors, coronary computed tomography angiography (CCTA) is very effective in ruling out coronary atherosclerosis, or at the other extreme, in estimating the risk of major adverse cardiovascular events based on disease anatomy.

“Rarely, however, is a single non-invasive test sufficient to diagnose obstructive disease of the epicardial coronary arteries and a sequential approach is required. When CCTA reveals coronary blockages of intermediate severity, additional tests like stress echocardiography, stress positron emission tomography or stress cardiac magnetic resonance perfusion imaging, if available, are recommended to evaluate the functional significance of the blockages. These additional exams also help to diagnose ANOCA/INOCA when CCTA does not reveal any blockages,” explains Professor Vrints.

“In patients with large coronary artery blockages, surgical or percutaneous revascularization is recommended for specific anatomical and/or clinical groups of patients in whom revascularization over medical therapy alone has been shown to prolong survival and to reduce deaths from cardiovascular causes, as well as spontaneous myocardial infarctions and symptoms caused by cardiac ischemia,” says guidelines co-chair Professor Felicita Andreotti, Fondazione Policlinico Universitario Gemelli IRCCS and Catholic University Medical School, Rome, Italy.

Prof. Andreotti adds that representatives of the European Association for Cardio-Thoracic Surgery (EACTS) and representatives of the Patient Forum were included in the 28-member task force and that the Guidelines have been endorsed by the EACTS.

The indications for coronary revascularization in the 2024 Guidelines are largely similar to those of 2018: namely, symptoms related to ischemia that are refractory to medical therapy alone, and/or significant disease of the left main stem, of the proximal left anterior descending artery, or of multiple large epicardial arteries.

The Guidelines state/recommend that the most appropriate revascularization modality should be selected based on the patient’s profile, coronary anatomy, procedural factors, patient preferences and outcome expectations. Surgery, if possible, is preferred over percutaneous coronary intervention in patients with extensive disease, especially those with diabetes or reduced left ventricular ejection fraction.

When performing revascularization via percutaneous coronary intervention, intracoronary imaging, in addition to pressure measurements, is helpful to guide interventions and enhance immediate and long-term results, especially in complex anatomical scenarios such as left main disease, bifurcations, or long lesions.

“Percutaneous coronary intervention using modern thin-strut stents allows patients who are not at high ischemic risk and/or who are at high bleeding risk to safely shorten the duration of dual antiplatelet therapy. In all or in certain subgroups of patients with chronic coronary syndromes, new lipid-lowering, metabolic and anti-inflammatory medical strategies have the potential to lower the risk of adverse cardiovascular events,” adds Professor Andreotti.

“Patient education and involvement in decision-making and self-care, along with mobile-health interventions and simplified medication regimens, have the potential to improve adherence to healthy lifestyles and to medical therapy, and to enhance long-term patient monitoring for disease complications and side effects of treatment,” explains Professor Vrints.

The Guidelines co-chairs conclude, “Chronic coronary syndromes are a global health concern because transient or long-lasting damage of the heart caused by diseases of the coronary circulation can cause ineffective heart pump function or malignant arrhythmias that can be fatal. Coronary syndromes remain the single largest cause of death in the adult population worldwide, resulting in millions dying every year. Therefore, the new guidelines stress the importance of early detection, appropriate treatment, and careful long-term follow-up.”