Coronary artery bypass grafting (CABG) is a surgical procedure that improves blood flow to the heart by using a healthy blood vessel from elsewhere in the body to develop a new pathway around an artery blockage. Patients who have undergone prior CABG and have an acute coronary syndrome (ACS, a range of conditions in which blood flow to the heart is abruptly reduced or stopped) experience worse outcomes, and the best treatment strategy for this population remains unclear.
In a recent publication in Atherosclerosis, researchers from the CVC examined a group of patients with prior CABG and ACS to describe their clinical characteristics and outcomes based on ACS classification type and selected treatment strategies. The study’s primary outcome was a combination of death and myocardial infarction (heart attack) at the one-year mark.
The researchers utilized a series of linked administrative health databases in Alberta, Canada to identify all patients with prior CABG who presented with ACS between 2009 and 2019. Of the 54,641 patients with an ACS, they identified 1,670 with a prior history of CABG. These patients were then divided into two ACS cohorts: (1) 183 patients who presented with ST-elevation myocardial infarction (STEMI), a severe heart attack caused by a completely blocked coronary artery, and (2) 1,487 patients who presented with non-ST segment elevation ACS, which includes non-STEMI, a heart attack caused by a partially blocked coronary artery, and unstable angina, chest pain due to reduced blood flow.
The researchers found that patients treated more invasively with percutaneous coronary intervention, a procedure to open a blocked artery, showed improved outcomes. Despite these noted improvements, approximately two-thirds of patients were treated with only medical therapy, a more conservative approach that was associated with a higher risk of adverse events. The researchers emphasize that further study is needed to better understand and optimize the treatment strategies available to this patient population.
This publication was co-authored by the CVC’s Pishoy Gouda, MB, BCh, BAO, MSc (Interventional Cardiology Fellow), Sunjida Islam, MBBS, MSc, Doug Dover, PhD, Padma Kaul, PhD, Kevin Bainey, MD, MSc, and Robert Welsh, MD.