For individuals undergoing coronary artery bypass grafting (CABG) to address multivessel coronary artery disease, two common surgical approaches – radial artery plus one internal thoracic artery (SITA+RA) and bilateral internal thoracic artery (BITA) grafting – demonstrate largely comparable long-term survival rates, according to research presented at the annual meeting of the Society of Thoracic Surgeons, held from to in New Orleans.
The study, led by Dr. Thomas Schwann of Corewell Health William Beaumont University Hospital in Royal Oak, Michigan, examined outcomes in over 158,000 patients younger than 90 years old who underwent their first, non-emergency CABG procedure for multivessel disease. Researchers analyzed data from 81,719 patients receiving SITA+RA and 76,496 patients receiving BITA.
Over the past decade, the use of multiarterial CABG has increased in the United States, rising from 9% to over 16%, primarily driven by increased adoption of the SITA+RA technique, with a more modest increase in BITA utilization. Initial analysis showed excellent survival rates with both approaches. Interestingly, BITA grafting showed a slight incremental survival benefit compared to SITA+RA. Further analysis revealed an additional survival benefit associated with the use of a third arterial conduit.
A propensity score-matched analysis, involving over 66,000 pairs of patients, demonstrated equivalent 15-year survival rates between the BITA and SITA+RA groups across the entire patient population. However, the researchers observed a nuanced pattern based on age. BITA grafting showed superior survival in younger patients, while SITA+RA grafting demonstrated improved survival in patients aged 70 years or older. Landmark analyses indicated a trend toward improved zero- to five-year survival with SITA+RA, while BITA showed a trend toward better outcomes after 10 years.
The study also investigated the impact of adding additional arterial conduits beyond two. Compared to both SITA+RA and BITA strategies, incorporating additional conduits (BITA+RA) was associated with a similarly decreased risk-adjusted mortality.
“Given the improved survival associated with additional arterial grafts beyond two, this should encourage and challenge surgeons to use as many arterial grafts as possible to optimize outcomes,” Dr. Schwann stated.
Coronary artery bypass grafting is a surgical procedure used to improve blood flow to the heart. It involves taking a healthy blood vessel from another part of the body – often the leg, arm, or chest – and using it to create a detour around a blocked coronary artery. This allows blood to flow more freely to the heart muscle, relieving symptoms of coronary artery disease, such as chest pain and shortness of breath.
The internal thoracic arteries (ITAs) are often preferred for CABG due to their excellent long-term patency rates – meaning they remain open and functional for a longer period compared to other grafts, such as those harvested from the leg. The radial artery, located in the arm, is another commonly used arterial conduit. The choice between SITA+RA and BITA, and the potential addition of further arterial conduits, represents a key decision point in CABG surgery, aiming to maximize long-term benefits for each patient.
This research highlights the evolving landscape of CABG techniques and the importance of individualized treatment strategies. While both SITA+RA and BITA grafting offer comparable long-term survival, the optimal approach may vary depending on patient age and other clinical factors. The findings also underscore the potential benefits of utilizing as many arterial conduits as feasible to further improve outcomes.
