Log in to MyACC
Sex-Related Differences in Multiple vs. Single Arterial CABG
Quick Takes
- Compared to single arterial grafting, multiple arterial revascularizations (MAG) are associated with improved long-term survival for women as well as men.
- Men MAG patients had a reduced rate of 30-day hospital readmission for myocardial infarction and angina but increased rate of deep sternal wound infections potentially due to bilateral internal mammary artery harvesting.
- The women MAG patients, in contrast, developed a different short-term clinical manifestation by demonstrating increased congestive heart failure compared to SAG, which would require more thorough investigation.
Study Questions:
What is the long-term survival of using multiple arterial grafting (MAG) versus single arterial grafting (SAG) in women and men undergoing coronary artery bypass grafting (CABG)?
Methods:
This retrospective study used the Australian and New Zealand Society of Cardiothoracic Surgical Database with linkage to the National Death Index. Patients from 2001 to 2020 were identified. Sex-stratified, inverse probability weighted Cox proportional hazard model was used to facilitate survival comparisons. The primary outcome was all-cause mortality. The secondary evaluation captured binary short-term outcomes, including 30-day mortality and 30-day readmission to the hospital due to a composite of myocardial infarction, deep sternal wound infection, arrhythmia, congestive heart failure, or recurrent angina, as well as each of the individual components.
Results:
A total of 54,275 adult patients receiving at least two grafts in primary isolated bypass operations were analyzed; 19.7% were female patients and 54.7% received multiple arterial grafting in this cohort. Overall, the survival benefit for MAG was better than SAG in both sexes, despite less women receiving MAG. During almost 5 years of follow-up, mortality was significantly lower in male patients undergoing multiarterial than single arterial procedures (adjusted hazard ratio [aHR], 0.82; 95% confidence interval [CI], 0.77–0.87; p < 0.001). The survival benefit was also significant for females (aHR, 0.83; 95% CI, 0.76–0.91; p < 0.001) at a median (interquartile range) follow-up of 5.2 (2.4–8.7) years. The survival benefits associated with MAG were consistent across all sex-stratified subgroups except for female patients with left main coronary disease, which showed borderline significance (HR, 0.89; 95% CI, 0.76–1.04; p = 0.1) likely due to limited statistical power.
Conclusions:
This sex-stratified study was performed by comparing the long- and short-term clinical outcomes of MAG versus SAG. The rate of MAG (54.7%) was considerably higher than most world practice. The authors found a significantly improved late survival following MAG in both men and women. Women patients received a lesser number of grafts and lesser use of MAG than male patients in Australia, despite both women and men reporting a similar number of diseased coronary territories.
Perspective:
Intravascular ultrasound assessments from prior studies reveal that women have smaller coronary artery diameters regardless of body size, potentially complicating CABG and elevating the risk of perioperative mortality and incomplete revascularization. This anatomical difference in coronary artery disease between the two sexes might lead to less complete revascularization, as seen in this study, and is also supported by other studies from the Society of Thoracic Surgeons Database, which showed 22% less utilization of MAG in women as compared to men (adjusted odds ratio, 0.78; 95% CI, 0.75–0.81; p < 0.001). Despite this, women tend to derive the same benefit in long-term survival. This study highlights another gap in the type of revascularization between the genders. This gap was evident by performing a sex-stratified analysis, and while most revascularization studies are largely men, this stratification helps bring out the important differences in the two groups.
Clinical Topics: Cardiac Surgery, Invasive Cardiovascular Angiography and Intervention
Keywords: Coronary Artery Bypass, Myocardial Revascularization, Sex Characteristics
< Back to Listings
