Summary of non-pharmacological interventions in stable coronary artery disease

Most of included patients in the trials discussed in this section had stable coronary artery disease, and our discussion focuses on this population.

Revascularization with coronary artery bypass grafting (CABG)

• In patients with stable angina, the evidence for up-front CABG plus medical therapy vs medical therapy alone is not strong and comes from old trials prior to the development and adoption of contemporary medical therapies like statins and inhibitors of the renin-angiotensin-aldosterone system.

• There are three large trials in this area. Two of the trials were nonsignificant - the Veterans Administration Cooperative Study and the CASS study, while the European Coronary Surgery Study was positive.

• In the European Coronary Surgery Study, CABG reduced death over 5 years with a number need to treat (NNT) of approximately 11 patients .

• A patient-level meta-analysis of the three aforementioned trials plus four additional smaller trials, famously known as the Yusef et al meta-analysis, found that CABG reduced death at 10 years with a NNT of approximately 24 patients. Benefit with CABG was seen in patients with left main, left anterior descending artery or three vessel disease.

• There are, however, several important consideration: First, patients with left main disease represented a small number of patients. Second, internal mammary artery grafts were used in only 10% of the patients. Third, included patients were young men (average age 51 years and 97% were men). Therefore, there is a need for a pragmatic trial to test the efficacy of up-front CABG plus medical therapy versus medical therapy alone in the current era, specially in patients older than 60 years of age, who have multiple comorbidities.

Revascularization with percutaneous coronary interventions

• In patients with stable coronary artery disease, percutaneous transluminal coronary angioplasty (PTCA) had modest improvement in symptoms as seen in ACME and RITA-2. This endpoint is subject to bias due to lack of blinding. In RITA-2, PTCA compared to medical therapy worsened the primary outcome of all-cause death or non-fatal myocardial infraction with a number needed to harm of approximately 33 patients over 2.7 years of follow up. This difference was largely due to more non-fatal myocardial infarction in the PTCA arm. Therefore, PTCA is not recommended for patients with stable coronary artery disease.