From stable CAD to chronic coronary syndromes: Evolving terminology in cardiovascular disease

Just how stable are patients with stable CAD?

The ESC guidelines updated their terminology from ‘stable CAD’ to ‘chronic coronary syndromes’ in 2019

In 2019, the European Society of Cardiology (ESC) published new clinical practice guidelines on the management of ‘chronic coronary syndromes’ (CCS). The ESC has never published guidelines on CCS before, so what is this new condition?

The 2019 guidelines replace those issued in 2013 on stable coronary artery disease (CAD). However, the word ‘stable’ was perhaps a misnomer. ‘Stable’ suggested that these patients had a low risk of events, so the change to CCS reflects the reality that patients with CAD are at continuing risk of myocardial infarction (MI) and stroke.

What does the change in terminology mean for you and your patients?

The myth of stable CAD

The definition of stable patients used in the 2013 ESC CAD guidelines included those who have become asymptomatic after an acute ischaemic event as well as those without a prior ischaemic event but with mild symptoms such as stable angina. However, clinical data show that both of these patient groups are at high risk of events such as stroke, MI and cardiovascular (CV) death, and this may challenge use of the description ‘stable’.

Patients without prior ischemic events in the REACH registry had a high risk of a first event

In the REACH registry, well-managed patients with stable atherosclerosis had a 12.2% risk of major adverse CV events (MACE; stroke, MI or CV death) over 4 years even if they had no previous event. Data from a Swedish registry paint a similar picture of continuing risk in patients who had an MI and were receiving a high standard of secondary prevention therapies. As would be expected, the risk of recurrence was high within the 12 months immediately following a patient’s first event, with 18.3% of patients experiencing a MACE in this time. However, the risk of MACE continued, and 20.0% of patients who were event free for the first year had an event in the next 3 years, highlighting the continuing risk in these patients.

Patients who have not had a recurrent MI within 1 year of their index event still have a 20.0% risk of recurrent MI over the subsequent 3 years

What are chronic coronary syndromes?

In addition to using ‘chronic’ instead of ‘stable’, the guidelines have moved on from ‘coronary artery disease’ to ‘coronary syndromes’. ‘Syndromes’ is not a plural by accident and serves to highlight the heterogeneity in this patient population. Accordingly, six clinical scenarios are included in the definition. These scenarios cover a range of patients including those who have stabilized symptoms after an acute event and patients who have yet to have an event but have clear evidence for clinically significant atherosclerosis.

Definition of chronic coronary syndromes in the 2019 ESC guidelines

Following this update to the terminology, CAD is now clearly divided into two main clinical presentations: CCS and acute coronary syndromes. Given the dynamic nature of CAD, the needs of an individual patient will change depending on how their condition develops and their risk of acute events changes. For example, a patient with CCS may develop peripheral artery disease, which is associated with a higher risk of ischaemic events and may necessitate additional protection with intensified antithrombotic therapy.

Managing chronic coronary syndromes

As well as changing terminology, the guidelines provided new recommendations on how to manage continuing risk of ischaemic events. A major change was the inclusion of a Class IIa recommendation that patients with CCS at high risk of further events and low risk of bleeding should receive an additional antithrombotic such as rivaroxaban vascular dose 2.5 mg twice daily (bid) in addition to aspirin. For full details on the change in guidelines read our newsletter here.

2019 ESC guidelines for the management of chronic coronary syndromes

Summary

The change in terminology from stable CAD to CCS highlights the continuing risk of MACE in these patients. As Professor Jan Steffel explains in the video below

“We realise that these patients are only stable in relative terms, but not in absolute terms … this is the kind of patient population that deserves, and requires, additional therapy.”

What evidence drove the change in the ESC guidelines in CCS?

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