Coronary artery disease: Risk stratification and patient selection for more aggressive secondary prevention

In patients with stable coronary artery disease, clinical outcomes are predominantly characterized by the consequences of atherosclerosis on the myocardium, but also by complications of atherosclerosis, notably recurrent acute coronary syndrome or stroke. Secondary prevention therapy is therefore key in this patient population. Intensification of secondary prevention therapy is possible, at the price of a therapeutic risk or a high cost, therefore justifying careful selection of patients with a high residual risk and low therapeutic risk. Two lines of therapy can be intensified, independently of each other, namely anti-thrombotics and lipid-lowering agents. Intensification of anti-thrombotic therapy is efficacious in terms of ischaemic events and cardiovascular mortality, but incurs an excess haemorrhagic risk. Patients aged over 65 years of age and those with a history of intra-cranial haemorrhage are not eligible for intensification of anti-thrombotic therapy. Conversely, patients with prior or recurrent myocardial infarction may benefit from this strategy, especially if they are current smokers or have diabetes mellitus. Intensification of lipid-lowering therapy can be achieved through an association of high-intensity statins with ezetimibe or PCSK9 inhibitors. This strategy engenders little risk, but the cost of PCSK9 inhibition is high, and should be considered based on the level of low-density lipoprotein cholesterol achieved with statin treatment at the maximal tolerated dose. In addition to this patient selection based on low-density lipoprotein cholesterol levels, the presence of diabetes or documented progression of atherosclerosis should be considered.