Follow-up of Patients With Multivessel Coronary Artery Disease After CABG (FAMOUS)

"Long-term Follow-up of Patients With Multivessel Coronary Artery Disease Undergoing CABG - Comparison Between Functional, Anatomical, or Medical Only-Based Evaluation to Prevent Cardiovascular Events - The FAMOUS Trial"

The FAMOUS Trial is a single-center, prospective, randomized study aimed to compare three different strategies (clinical, anatomical, or functional) in preventing MACE after CABG. A total of 600 patients will be included and followed for 5 years. Patients will be randomly allocated (1:1:1) in one of the three follow-up strategies. Patients in the clinical arm will be followed by regular medical visits only every 6 months; patients in the functional arm will undergo a myocardial perfusion scan, and those in the anatomical arm will be subjected to a coronary CT. Non-invasive tests will be performed per protocol and regardless symptoms every 2 years after the first year post-surgery. The primary outcome will be the incidence of death, acute myocardial infarction or myocardial revascularization.

Background: Coronary artery disease (CAD) is a highly prevalent clinical condition, usually associated with impairment in quality of life, and with a high risk for cardiovascular events including myocardial infarction and cardiovascular death. Because of the anatomical and/or functional extension of the disease, combined with high-risk clinical features (left ventricular dysfunction, diabetes, or chronic kidney disease to name a few), many patients must undergo a coronary artery bypass grafting (CABG) surgery. In the USA, 400,000 CABG surgeries are performed annually. Although the benefits of CABG for those high-risk patients have been well established in the long-term, the best follow-up strategy after surgery is still controversial. Current guidelines generally recommend that the follow-up of patients after CABG should be based on the same strategies proposed for patients with stable angina. The investigators hypothesized that the early identification of myocardial ischemia or progression of coronary atherosclerosis, even in asymptomatic patients, may be superior to clinical follow-up alone for the prevention of cardiovascular events.

Myocardial perfusion stress test using cardiac scintigraphy (Sestamibi) at rest and during pharmacological stress (dipyridamole)

Myocardial perfusion scan will be performed at rest and during pharmacological stress with dipyridamole (99mTc-Sestamibi)

Coronary CTA will be performed using a 320-detector scanner, 0.5 mm slice thickness, with gantry rotation of 350ms. Prior to each scan, the patient's blood pressure and heart rate will be assessed, and if the heart rate is above 70bpm, beta-blockers will be given orally. Following oral beta blocker administration, if the heart rate is still greater than 64bpm, intravenous metoprolol will be administered. A total of 70-100 mL of iodinated contrast will be administered via an automated injector at a rate of 5mL/s. All coronary CTA images will be transferred to a workstation (Vitrea FX-Vital Image) and analyzed by two experienced cardiac imagers who are blinded to all other data using a standard 18-segment coronary tree model.

Death related to cardiovascular events including sudden death, and death due to acute coronary syndromes (unstable angina, myocardial infarction), heart failure, myocardial revascularization procedures

Inclusion Criteria: Documented obstructive coronary artery disease Isolated, recent CABG (< 30 days from inclusion) Exclusion Criteria: Concomitant, severe heart disease from other etiologies including valvular heart disease, advanced dilated cardiomyopathy, etc Glomerular filtration rate < 30mL/min/1.73m2