Residual MACE in CAD: What Are the Long-Term Adverse Cardiac Events to Worry About?

Symptomatic coronary artery disease (CAD) affects over 150 million patients worldwide and is caused when atherosclerotic plaques form in the coronary arteries, limiting blood flow to the heart. The rupture of one of these plaques can lead to the formation of a blood clot, which partially or completely blocks blood flow, leading to an acute myocardial infarction (MI). Because atherosclerosis very often develops systemically, patients with CAD often have plaques in the lower limb arteries or the carotid arteries as well. CAD is therefore frequently associated with a variety of ischaemic events, such as stroke and ischaemic events in the legs.

Most clinical trials in this therapy area measure the composite endpoint of major adverse cardiovascular events (MACE), the combination of MI, stroke or death from cardiovascular causes. MACE are the most severe atherothrombotic events, and the most feared by patients because of their high risk of mortality or irreversible harm. Unfortunately, they are also relatively common – in the REACH registry, MACE affected nearly 1 in 20 patients with CAD over a 1-year timeframe. This risk is even greater in certain types of patients, such as those with polyvascular disease or those with co-morbidities such as heart failure or diabetes (Table). Patients with chronic kidney disease alongside CAD are also at a higher risk of MACE, compounded by the fact that they often do not receive the same medications offered to patients with normal renal function. With multiple risk factors (e.g. co-morbidities or older age), the risk of MACE increases still further (Figure 1).

Table. Selected high-risk subgroups based on data from the REACH registry.