Sex Differences in Coronary Artery Bypass Grafting Techniques: A STS Database Analysis

Sex-Based Differences in Concomitant Tricuspid Repair During Degenerative Mitral Surgery

BACKGROUND

Women with mitral valve disease have higher rates of tricuspid regurgitation (TR) than men. Although tricuspid valve repair (TVr) decreases the progression of TR, we hypothesize that there may be sex-based differences in concomitant TVr at the time of mitral valve operations.

METHODS

Adults undergoing mitral valve operation for degenerative disease with moderate or worse preoperative TR at a high-volume center from 2014 to 2023 were identified. Patients with a previous tricuspid intervention were excluded. A multivariable logistic regression identified predictors of concomitant TVr. To evaluate the clinical impact of not performing TVr, a competing risk model compared development of severe TR or valve-related reoperation by sex among patients without TVr.

RESULTS

Most included patients were women (55% [n = 214 of 388]), and the median age was 73 years (quartile 1-quartile 3, 65-79 years). There was no difference in the rate of severe TR by sex (female, 28%; male, 26%; P = .63). The unadjusted rate of concomitant TVr was 57% for women and 73% for men (P < .001). Overall, women had 52% lower adjusted odds of TVr (adjusted odds ratio, 0.48; 95% CI, 0.29-0.81; P = .006), including a lower adjusted rate for moderate TR (47% [95% CI, 45%-49%] vs 66% [95% CI, 64%-69%]) and for severe TR (83% [95% CI, 81%-86] vs 92% [95% CI, 90%-93%]) Among those without TVr, 12% of women and 0% of men had severe TR or required a valve-related reoperation at 4 years (P < .001).

CONCLUSIONS

Women with moderate or severe TR undergoing mitral valve operation for degenerative disease were less likely to receive concomitant TVr, severe TR was more likely to develop, or they would more likely need a valve-related reoperation. Evaluation of sex-based treatment differences is imperative to improve outcomes for women.

Sex Disparities After Coronary Artery Bypass Grafting and Hospital Quality

Importance

Concern has been raised about persistent sex disparities after coronary artery bypass grafting, with female patients having higher mortality. However, whether these disparities persist across hospitals of different qualities is unknown.

Objective

To evaluate sex disparities in 30-day mortality after coronary artery bypass grafting across high- and low-quality hospitals.

Design, Setting, and Participants

This cross-sectional, retrospective cohort study evaluated Medicare beneficiaries undergoing coronary artery bypass grafting between October 1, 2015, and March 31, 2020. Data analysis was performed from July 1, 2023, to December 1, 2023.

Exposures

The primary exposures were hospital quality and sex. For hospital quality, hospitals were placed into rank order by their overall risk-adjusted mortality rate and divided into quintiles.

Main Outcome and Measures

Risk-adjusted 30-day mortality using a logistic regression model accounting for patient factors, including sex, age, comorbidities, elective vs unplanned admission, number of bypass grafts, use of arterial graft, and year of surgery.

Results

A total of 444 855 beneficiaries (mean [SD] age, 71.5 [7.5] years; 120 333 [27.1%] female and 324 522 [72.9%] male) were studied. Compared with male beneficiaries, female beneficiaries were more likely to have an unplanned admission (66 425 [55.2%] vs 157 895 [48.7%], P < .001) and receive care at low-quality (vs high-quality) hospitals (odds ratio, 1.26; 95% CI, 1.23-1.29; P < .001). Overall, risk-adjusted female mortality was 4.24% (95% CI, 4.20%-4.27%), and male mortality was 2.75% (95% CI, 2.75%-2.77%), with an absolute difference of 1.48 (95% CI, 1.45-1.51) percentage points (P < .001). At the highest-quality hospitals, male mortality was 1.57% (95% CI, 1.56%-1.59%), and female mortality was 2.58% (95% CI, 2.54%-2.62%), with an absolute difference of 1.01 (95% CI, 0.97-1.04) percentage points (P < .001). At the lowest-quality hospitals, male mortality was 4.94% (95% CI, 4.88%-5.01%), and female mortality was 7.02% (95% CI, 6.90%-7.13%), with an absolute difference of 2.07 (95% CI, 1.95-2.19) percentage points (P < .001). Female beneficiaries receiving care at low-quality hospitals had a higher mortality than male beneficiaries receiving care at the high-quality hospitals (7.02% vs 1.57%, P < .001).

Conclusions and Relevance

In this cohort study of Medicare beneficiaries undergoing coronary artery bypass grafting, female beneficiaries were more likely to receive care at low-quality hospitals, where the sex disparity in mortality was double that of high-quality hospitals. Quality improvement targeting low-quality hospitals as well as equitable referral of female beneficiaries to higher-quality hospitals may narrow the sex disparity after coronary artery bypass grafting.

Multiple arterial vs. single arterial coronary artery bypass grafting: sex-related differences in outcomes

BACKGROUND AND AIMS

Uncertainty exists over whether multiple arterial grafting has a sex-related association with survival after coronary artery bypass grafting. This study aims to compare the long-term survival of using multiple arterial grafting vs. single arterial grafting in women and men undergoing coronary artery bypass grafting.

METHODS

The 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.

RESULTS

A total number of 54 275 adult patients receiving at least two grafts in primary isolated bypass operations were analysed. The entire study cohort consisted of 10 693 (19.7%) female patients and 29 711 (54.7%) multiple arterial grafting procedures. At a median (interquartile range) postoperative follow-up of 4.9 (2.3-8.4) years, mortality was significantly lower in male patients undergoing multiarterial than single arterial procedures (adjusted hazard ratio 0.82; 95% confidence interval 0.77-0.87; P < .001). The survival benefit was also significant for females (adjusted hazard ratio 0.83; 95% confidence interval 0.76-0.91; P < .001) at a median (interquartile range) follow-up of 5.2 (2.4-8.7) years. The interaction model from Cox regression suggested insignificant subgroup effect from sex (P = .08) on the observed survival advantage. The survival benefits associated with multiple arterial grafting were consistent across all sex-stratified subgroups except for female patients with left main coronary disease.

CONCLUSIONS

Compared to single arterial grafting, multiple arterial revascularization is associated with improved long-term survival for women as well as men.

Patient-physician sex concordance and outcomes in cardiovascular disease: a systematic review

The sex disparity in outcomes of patients with cardiovascular disease is well-described and has persisted across recent decades. While there have been several proposed mechanisms to explain this disparity, there are limited data on female patient-physician sex concordance and its association with outcomes. The authors review the existing literature on the relationship between patient-physician sex concordance and clinical outcomes in patients with cardiovascular disease, the evidence of a benefit in clinical outcomes with female patient-physician sex concordance, and the possible drivers of such a benefit and highlight directions for future study.

Evaluation of sex differences in the receipt of concomitant atrial fibrillation procedures during nonmitral cardiac surgery

OBJECTIVE

Women are less likely to receive guideline-recommended cardiovascular care, but evaluation of sex-based disparities in cardiac surgical procedures is limited. Receipt of concomitant atrial fibrillation (AF) procedures during nonmitral cardiac surgery was compared by sex for patients with preoperative AF.

METHODS

Patients with preoperative AF undergoing coronary artery bypass grafting and/or aortic valve replacement at any of the 33 hospitals in Michigan from 2014 to 2022 were included. Patients with prior cardiac surgery, transcatheter AF procedure, or emergency/salvage status were excluded. Hierarchical logistic regression identified predictors of concomitant AF procedures, account for hospital and surgeon as random effects.

RESULTS

Of 5460 patients with preoperative AF undergoing nonmitral cardiac surgery, 24% (n = 1291) were women with a mean age of 71 years. Women were more likely to have paroxysmal (vs persistent) AF than men (80% vs 72%; P < .001) and had a higher mean predicted risk of mortality (5% vs 3%; P < .001). The unadjusted rate of concomitant AF procedure was 59% for women and 67% for men (P < .001). After risk adjustment, women had 26% lower adjusted odds of concomitant AF procedure than men (adjusted odds ratio, 0.74; 95% CI, 0.64-0.86; P < .001). Female sex was the risk factor associated with the lowest odds of concomitant AF procedure.

CONCLUSIONS

Women are less likely to receive guideline recommended concomitant AF procedure during nonmitral surgery. Identification of barriers to concomitant AF procedure in women may improve treatment of AF.

Sex Disparities in Cardiovascular Disease

Cardiovascular disease is the leading cause of death in women. It remains underdiagnosed, undertreated, and portends worse outcomes in women than men. Disparities exist in every stage of science, from bench research to the editorial board of major journals and in every cardiovascular subspecialty. This review summarizes differences in cardiovascular risk factors and disparities in management and outcomes of ischemic heart disease, heart failure, aortic stenosis, and atrial fibrillation. It also provides an overview of female representation as participants and leaders of clinical trials, editorial boards, and academic institutions. Strategies to overcome these disparities are proposed with examples of successful programs.

Comparative Analysis of Coronary Artery Bypass Grafting Outcomes in Women Using Different Conduits in the National UK Data Set

BACKGROUND

There is limited report of outcomes in women undergoing isolated coronary artery bypass grafting (CABG) with left internal thoracic artery and different second conduits (saphenous vein graft [SVG], radial artery [RA], and right internal thoracic artery [RITA]).

METHODS

The National Adult Cardiac Surgery Audit database was queried for women undergoing isolated CABG with left internal thoracic artery graft in the United Kingdom from 1996 to 2019. Propensity score-based pairwise comparisons were performed between graft types. The primary outcome was in-hospital mortality.

RESULTS

The study included 58,063 women (SVG, n = 48,881 [84.2%]; RA, n = 6136 [10.6%]; RITA, n = 2445 [4.2%]). SVG use was stable over the years; RA and RITA use decreased. In-hospital mortality was similar between the RA and RITA grafts (2.3% vs 2.8%; odds ratio [OR], 0.80; 95% CI, 0.53-1.22; P = .39) and between the RA and SVG (2.3% vs 2.0%; OR, 1.20; 95% CI, 0.93-1.55; P = .17) but higher in the RITA group compared with the SVG (2.7% vs 1.4%; OR, 2.04; 95% CI, 1.27-3.36; P = .004). Women receiving the RITA graft were more likely to have sternal wound infection (SWI) compared with the RA (0.6% vs 0.06%; P = .004) and the SVG (0.6% vs 0.2%; P = .032). SWI was consistently associated with higher risk of in-hospital mortality.

CONCLUSIONS

Conduit selection may affect operative outcomes in women undergoing CABG. The RA shows similar mortality and risk of deep SWI as the SVG.

Coronary artery bypass surgery versus percutaneous interventions for women with multivessel coronary artery disease

OBJECTIVE

To compare outcomes in women undergoing percutaneous coronary intervention (PCI) and coronary artery bypass graft (CABG) surgery.

DESIGN

This retrospective, propensity-score matched cohort study from the New York State cardiac registry (2012-2018) included all women with multivessel coronary artery disease undergoing PCI with everolimus-eluting stents (EES) and CABG surgery. The primary outcome was all-cause mortality. The key secondary outcome was major adverse cardiac events, defined as the composite of all-cause mortality, myocardial infarction, and stroke.

RESULTS

PCI with EES was associated with a higher 6-year risk of mortality (25.75% vs 23.57%; adjusted hazard ratio [AHR], 1.29; 95% confidence interval [CI], 1.14-1.45). PCI also was associated with a higher rate of the composite outcome of death, myocardial infarction, and stroke (36.58% vs 32.89%; AHR, 1.28; 95% CI, 1.17-1.41), as well as myocardial infarction (14.94% vs 9.12%; AHR, 1.84; 95% CI, 1.56-2.17), but not stroke (7.07% vs 7.62%; AHR, 0.83; 95% CI, 0.67-1.03). Repeat revascularization rates also were higher for women undergoing PCI (21.53% vs 11.57%; AHR, 1.88; 95% CI, 1.63-2.17). There was no difference in mortality between the 2 interventions when PCI patients received complete revascularization or had noncomplex lesions and for women without diabetes.

CONCLUSIONS

For women with multivessel coronary artery disease, CABG surgery is associated with lower 6-year mortality, myocardial infarction, and repeat revascularization rates compared to PCI with EES.

Sex Differences in Red Blood Cell Transfusions and 30-Day Mortality in Cardiac Surgery: A Single Center Observational Study

In cardiac surgery, women have higher short-term mortality and a higher risk of receiving red blood cell (RBC) transfusions than men. This study's aim was to evaluate possible sex differences in RBC transfusions in cardiac surgery and their association with preoperative hemoglobin levels, body mass index, and 30-day mortality. A single-center retrospective study was conducted with 1583 patients (1181 men and 402 women) undergoing cardiac surgery. A total of 64.4% of the women and 33.0% of the men received an RBC transfusion. In a multivariable analysis, female sex was an independent predictor of RBC transfusion (OR 3.88, 95% CI 2.95-5.11, p < 0.001). Other independent predictors of RBC transfusion were age, preoperative hemoglobin level, and body mass index. The women were more likely to receive RBC transfusions than the men, regardless of the type of cardiac surgery. Decreased transfusion risk was found in all higher-than-normal weight categories in the women, but only in the severe obesity category in the men. Preoperative hemoglobin was similarly associated with RBC transfusion in the men and women. The crude 30-day mortality rate was higher in the women than in the men (2.5% vs. 0.9%, p = 0.018). In both sexes, RBC transfusion was associated with an increased probability of death within 30 days.

Acute Coronary Syndromes in Women: A Narrative Review of Sex-Specific Characteristics

Acute coronary syndromes (ACSs) encompass a spectrum of life-threatening cardiovascular conditions, including unstable angina (UA) and myocardial infarction. While significant progress has been made in the understanding and management of ACS over the years, it has become increasingly evident that sex-based differences play a pivotal role in the pathophysiology, presentation, and outcomes of these conditions. Despite this recognition, the majority of clinical research in the field has historically focused on male populations, leading to a significant knowledge gap in understanding the unique aspects of ACS in women. This review article aims to comprehensively explore and synthesize the current body of literature concerning the sex-specific characteristics of ACS, shedding light on the epidemiology, risk factors, clinical presentation, diagnostic challenges, treatment strategies, and prognosis in women. By elucidating the distinct aspects of ACS in women, this review intends to foster greater awareness and improved clinical management, ultimately contributing to enhanced cardiovascular care for female patients.

The ISCHEMIA trial revisited: setting the record straight on the benefits of coronary bypass surgery and the misinterpretation of a landmark trial

OBJECTIVES

The ISCHEMIA trial is a landmark study that has been the subject of heated debate within the cardiovascular community. In this analysis of the ISCHEMIA trial, we aim to set the record straight on the benefits of coronary artery bypass grafting (CABG) and the misinterpretation of this landmark trial. We sought to clarify and reorient this misinterpretation.

METHODS

We herein analyse the ISCHEMIA trial in detail and describe how its misinterpretation has led to an erroneous guideline recommendation downgrading for prognosis-altering surgical therapy in these at-risk patients.

RESULTS

The interim ISCHEMIA trial findings align with previous evidence where CABG reduces the long-term risks of myocardial infarction and mortality in advanced coronary artery disease. The trial outcomes of a significantly lower rate of cardiovascular mortality and a higher rate of non-cardiovascular mortality with the invasive strategy are explained according to landmark evidence.

CONCLUSIONS

The ISCHEMIA trial findings are aligned with previous evidence and should not be used to downgrade recommendations in recent guidelines for the indisputable benefits of CABG.

Pathophysiology and management of saphenous vein graft disease

INTRODUCTION

The saphenous vein graft (SVG) is the most used conduit in CABG. With standardization of its use as a conduit came an understanding of its accelerated atherosclerosis, known as saphenous vein graft disease (SVGD). Given its extensive use, a review of the pathophysiology and management of SVGD is important as we optimize its use.

AREAS COVERED

For this review, an extensive literature search was completed to identify and examine the evolution of SVG in CABG, mechanisms driving SVGD, and methods developed to prevent and manage it. This includes a review of relevant major papers and trials in this space.

EXPERT OPINION

Eras of evolution in SVG usage in CABG include an experimental era, era of SVG dominance in CABG, and the current era of mixed venous and arterial grafting. As SVGD was studied, the mechanisms behind it became more understood, and prevention and management methods were developed. As advances in surgical techniques and pharmacotherapy continue to reduce occurrence and severity of SVGD, long-term patency of SV grafts continues to improve and remain excellent in optimized settings. With continued innovation and improvement in operative techniques, the SVG conduit is and will remain an important player in the field of coronary bypass.

Early and midterm outcomes after off pump coronary artery bypass surgery

Purpose

There has been debate whether off pump coronary artery bypass surgery (OPCAB) has results comparable to conventional on pump bypass surgery. This has led to the low uptake of OPCAB in the West. In India, OPCAB is the default mode of coronary revascularization. However, there is scarce data on mid-term outcomes of OPCAB in our patients. This study aims to evaluate both short and mid-term mortality and analyze factors associated with mortality.

Methods

This is a single center study of all consecutive patients undergoing isolated OPCAB from October 2014 to December 2019. Patient data was collected from hospital records and follow-up was from the hospital electronic medical records and telephone interviews. Mortality and factors contributing to survival were analyzed.

Results

Operative mortality was 2.3%. Mid-term mortality was 5.5%. Preoperative renal dysfunction, post-operative renal failure, use of the intra-aortic balloon pump (IABP), re-exploration for bleeding, postoperative stroke, ventilation > 24 h, and postoperative atrial fibrillation were associated with operative mortality. Factors associated with mid-term mortality were age > 62 years, postoperative renal failure, IABP usage, ventilation time > 24 h, and postoperative atrial fibrillation. The mean survival time was 2343.55 + / - 15.27 days and 6-year survival was 88.7%.

Conclusion

OPCAB can safely be performed with satisfactory short and mid-term outcomes. Further corroborative studies from different regions of the country or a multi-center study will help to establish the suitability of the technique in Indian patients.

Female gender does not have any significant impact on the early postoperative outcomes after coronary artery bypass grafting: a propensity-matched analysis

Purpose

Coronary artery bypass grafting (CABG) is the most common cardiac surgical procedure performed in India. There are fundamental differences between males and females in the incidence and responses of the body to various diseases. These differences are noticeable, more so in conditions relating to cardiovascular health, particularly coronary artery disease (CAD). This study aims to assess the gender differences in the early postoperative outcomes following CABG.

Methods

Between April 1999 through February 2018, 13,415 patients underwent isolated CABG in our practice. Propensity score matching was performed to yield 1825 well-matched pairs in each gender. These groups were compared in terms of various early postoperative outcomes.

Results

There were no significant differences between females and males in terms of early postoperative composite outcomes (4.2% vs. 5.2%) (odds ratio (OR) 0.82; 95% confidence interval (CI) 0.60-1.12, p = 0.213) of 30-day mortality, non-fatal myocardial infarction (MI), non-fatal cerebrovascular accidents (CVA), and need for renal replacement therapy (RRT), 30-day mortality (0.7% vs. 0.7%) (OR 1.11; 95%CI 0.50-2.45, p = 0.796), MI (2.7% vs. 3.1%) (OR 0.93; 95%CI 0.63-1.37, p = 0.708), CVA (0.4% vs. 0.8%) (OR 0.46; 95%CI 0.19-1.14, p = 0.096), and need for RRT (0.7% vs. 0.7%) (OR 0.88; 95%CI 0.40-1.93, p = 0.753).

Conclusion

Females have similar early postoperative outcomes compared to males in terms of composite outcomes of 30-day mortality, non-fatal MI, non-fatal CVA, and RRT among patients undergoing CABG. The outcomes are also similar when individually assessed. The off-pump technique has no additional benefit compared to the on-pump technique in females undergoing CABG.

Operative Outcomes of Women Undergoing Coronary Artery Bypass Surgery in the US, 2011 to 2020

Importance

It has been reported that women undergoing coronary artery bypass have higher mortality and morbidity compared with men but it is unclear if the difference has decreased over the last decade.

Objective

To evaluate trends in outcomes of women undergoing coronary artery bypass in the US from 2011 to 2020.

Design, Setting, and Participants

This retrospective cohort study at hospitals contributing to the Adult Cardiac Surgery Database of the Society of Thoracic Surgeons included 1 297 204 patients who underwent primary isolated coronary artery bypass from 2011 to 2020.

Exposure

Coronary artery bypass.

Main Outcomes and Measures

The primary outcome was operative mortality. The secondary outcome was the composite of operative mortality and morbidity (including operative mortality, stroke, kidney failure, reoperation, deep sternal wound infection, prolonged mechanical ventilation, and prolonged hospital stay). The attributable risk (the association of female sex with coronary artery bypass grafting outcomes) for the primary and secondary outcomes was calculated.

Results

Between 2011 and 2020, 1 297 204 patients underwent primary isolated coronary artery bypass grafting with a mean age of 66.0 years, 317 716 of which were women (24.5%). Women had a higher unadjusted operative mortality (2.8%; 95% CI, 2.8-2.9 vs 1.7%; 95% CI, 1.7-1.7; P < .001) and overall unadjusted incidence of the composite of operative mortality and morbidity compared with men (22.9%; 95% CI, 22.7-23.0 vs 16.7%; 95% CI, 16.6-16.8; P < .001). The attributable risk of female sex for operative mortality varied from 1.28 in 2011 to 1.41 in 2020, with no significant change over the study period (P for trend = 0.38). The attributable risk for the composite of operative mortality and morbidity was 1.08 in both 2011 and 2020 with no significant change over the study period (P for trend = 0.71).

Conclusions and Relevance

Women remain at significantly higher risk for adverse outcomes following coronary artery bypass grafting and no significant improvement has been seen over the course of the last decade. Further investigation into the determinants of operative outcomes in women is urgently needed.

Sex Disparities in Diagnostic Evaluation and Revascularization in Patients With Acute Myocardial Infarction-A 15-Year Nationwide Study

Background Although sex disparities in the diagnostic evaluation and revascularization of patients with acute myocardial infarction are well documented, no study has evaluated longitudinal trends in these disparities. Methods and Results Using the National Inpatient Sample from 2005 to 2019, 9 259 932 patients with acute myocardial infarction were identified. We divided 15 years into five 3-year periods. The primary objective was to evaluate sex-based trends in the use of diagnostic angiography, percutaneous coronary intervention, and coronary artery bypass graft (CABG) among patients with non-ST-segment-elevation myocardial infarction and ST-segment-elevation myocardial infarction (STEMI) over 15 years. The secondary objective was to evaluate sex disparities in mortality, length of stay, and cost. For non-ST-segment-elevation myocardial infarction, we saw a small reduction in sex disparity in the use of all diagnostic angiography in period 5 versus period 1 (4% versus 5.3%; P<0.01), no change in sex disparity in percutaneous coronary intervention use in period 5 versus period 1 (5.6% versus 5%; P=0.16), and a widening sex disparity in CABG in period 5 versus period 1 (5.4% versus 4.4%; P<0.01). However, we noted decreasing sex disparities in the use of diagnostic angiography, percutaneous coronary intervention, and CABG for ST-segment-elevation myocardial infarction in mostly all periods compared with period 1 (P<0.05, all comparisons), but differences still existed in period 5. Risk-adjusted in-hospital mortality was higher after CABG for non-ST-segment-elevation myocardial infarction and after percutaneous coronary intervention and CABG for ST-segment-elevation myocardial infarction in women than men. Conclusions Despite variable trends in sex disparities in diagnostic and revascularization procedures for acute myocardial infarction, disparities still exist.

The Society of Thoracic Surgeons Adult Cardiac Surgery Database: 2022 Update on Outcomes and Research

The Society of Thoracic Surgeons Adult Cardiac Surgery Database is the most mature and comprehensive cardiac surgery database. It is one of the most respected clinical data registries in health care, providing accurate risk-adjusted benchmarks, a foundation for quality measurement and improvement activities, and the ability to perform novel research. This report encompasses data from the years 2020 and 2021 and is the seventh in a series of reports that provide updated volumes, outcomes, database-related developments, and research summaries using the Adult Cardiac Surgery Database.

Vein Graft Use and Long-Term Survival Following Coronary Bypass Grafting

BACKGROUND

Although placement of at least 1 arterial graft during coronary artery bypass grafting (CABG) has a proven survival benefit, it is unknown what degree of revascularization with saphenous vein grafting (SVG) is associated with improved survival.

OBJECTIVES

The authors sought to determine whether undergoing surgery performed by a surgeon who is liberal with vein graft utilization is associated with improved survival in patients undergoing single arterial graft CABG (SAG-CABG).

METHODS

This was a retrospective, observational study of SAG-CABG performed in Medicare beneficiaries from 2001 to 2015. Surgeons were stratified by number of SVG utilized per SAG-CABG into conservative (≥1 SD below mean), average (within 1 SD of mean), and liberal (≥1 SD above mean). Long-term survival was estimated using Kaplan-Meier analysis and compared among surgeon groups before and after augmented inverse-probability weighting.

RESULTS

There were 1,028,264 Medicare beneficiaries undergoing SAG-CABG from 2001 to 2015 (mean age 72.0 ± 7.9 years, 68.3% male). Over time, 1-vein and 2-vein SAG-CABG utilization increased, whereas 3-vein and ≥4-vein SAG-CABG utilization decreased (P < 0.001). Surgeons who were conservative vein graft users performed a mean 1.7 ± 0.2 vein grafts per SAG-CABG, whereas those who were liberal vein graft users performed a mean 2.9 ± 0.2 vein grafts per SAG-CABG. Weighted analysis demonstrated no difference in median survival among patients undergoing SAG-CABG by liberal vs conservative vein graft users (adjusted median survival difference 27 days).

CONCLUSIONS

Among Medicare beneficiaries undergoing SAG-CABG, there is no association between surgeon proclivity for vein graft utilization and long-term survival, suggesting that a conservative approach to vein graft utilization is reasonable.

Sex Disparities in Failure to Rescue After Cardiac Surgery in California and New York

BACKGROUND

Women have a higher risk of mortality than men after cardiac surgery independent of other risk factors. The reason for this may not be limited to patient-specific variables. Failure to rescue (FTR) patients from death after a postoperative complication is a nationally endorsed quality care metric. We aimed to identify whether sex disparities exist in the quality of care after cardiac surgery using FTR rates.

METHODS

A retrospective analysis of 30 973 men (70.4%) and 13 033 women (29.6%) aged over 18 years undergoing coronary artery bypass graft or valve surgery in New York (2016-2019) and California (2016-2018) who experienced at least one serious postoperative complication. The primary outcome was the FTR. Multivariable logistic regression was used to identify predictors of death after complication. Propensity matching was used to adjust for baseline differences between sexes and yielded 12 657 pairs.

RESULTS

Female patients that experienced complications were older (mean age 67.8 versus 66.7, P<0.001), more frail (median frailty score 0.1 versus 0.07, P<0.001), and had more comorbidities (median Charlson score 2.5 versus 2.3, P<0.001) than male patients. The overall FTR rate was 5.7% (2524), men were less likely to die after a complication than women (4.8% versus 8%, P<0.001). Independent predictors of FTR included female sex (relative risk [RR]: 1.46 [CI, 1.30-1.62]), area-level poverty rate >20% (RR, 1.21 [CI, 1.01-1.59]), higher frailty (RR, 2.83 [CI, 1.35-5.93]), undergoing concomitant coronary artery bypass graft and valve surgeries (RR, 1.69 [CI, 1.49-1.9]), and higher number of postoperative complications (RR, 16.28 [CI, 14-18.89]). In the propensity-matched cohorts, the FTR rate remained significantly lower among men than women (6.0% versus 8.0%, P<0.001).

CONCLUSIONS

Women are less likely to be rescued from death following postoperative complications, independent of socioeconomic and clinical characteristics. Further research is warranted to investigate the clinical practices contributing to this disparity in quality of care following cardiac surgery.

Females have an increased risk of short-term mortality after cardiac surgery compared to males: Insights from a national database

OBJECTIVES

Female sex is considered a risk factor for mortality and morbidity following cardiac surgery. This study is the first to review the UK adult cardiac surgery national database to compare outcomes following surgical coronary revascularisation and valvular procedures between females and males.

METHODS

Using data from National Adult Cardiac Surgery Audit, we identified all elective and urgent, isolated coronary artery by-pass grafting (CABG), aortic valve replacement (AVR) and mitral valve replacement/repair (MVR) procedures from 2010 to 2018. We compared baseline data, operative data and outcomes of mortality, stroke, renal failure, deep sternal wound infection, return to theater for bleeding, and length of hospital stay. Multivariable mixed-effect logistical/linear regression models were used to assess relationships between sex and outcomes, adjusting for baseline characteristics.

RESULTS

Females, compared to males, had greater odds of experiencing 30-day mortality (CABG odd ratio [OR] 1.76, confidence interval [CI] 1.47-2.09, p < .001; AVR OR 1.59, CI 1.27-1.99, p < .001; MVR OR 1.37, CI 1.09-1.71, p = .006). After CABG, females also had higher rates of postoperative dialysis (OR 1.31, CI 1.12-1.52, p < .001), deep sternal wound infections (OR 1.43, CI 1.11-1.83, p = .005) and longer length of hospital stay (β 1.2, CI 1.0-1.4, p < .001) compared to males. Female sex was protective against returning to theater for postoperative bleeding following CABG (OR 0.76, CI 0.65-0.87, p < .001) and AVR (OR 0.72, CI 0.61-0.84, p < .001).

CONCLUSION

Females in the United Kingdom have an increased risk of short-term mortality after cardiac surgery compared to males. This highlights the need to focus on the understanding of the causes behind these disparities and implementation of strategies to improve outcomes in females.

Assessing sex-based differences in postsurgical clinical outcomes after use of del Nido cardioplegia

OBJECTIVES

del Nido cardioplegia is used to pharmacologically arrest the heart during cardiac surgery and decrease reperfusion- and ischaemia-related myocardial injury. Studies have demonstrated the physiological differences between male and female hearts, potentially related to cardiac size or myocyte calcium handling; we aimed to assess for between-sex differences in clinical outcomes after receipt of del Nido cardioplegia.

METHODS

Patients who underwent coronary artery bypass or coronary artery bypass graft/valve surgery at our institution using del Nido cardioplegia (January 2014 to December 2019) were included (n = 2118). Clinical data were collected retrospectively. After the creation of a propensity-matched cohort (n = 1252), multivariable logistic regression was used to analyse binary postoperative outcomes, and a Gamma model was used for a continuous postoperative outcome. Our primary end-point was a composite end-point comprised of 30-day mortality and/or need for a post-bypass mechanical support device.

RESULTS

The final cohort included 459 females and 793 males (matched up to 1:2, all standardized mean differences <0.1). Multivariable logistic regression showed that biological sex was not associated with the composite primary end-point (odds ratio = 0.898, P = 0.779). A Gamma model indicated that there were no sex-related differences in vasoactive-inotropic scores reflecting vasopressor and inotrope usage at the time of patient operating room exit (exp[est] = 1.394, P = 0.189).

CONCLUSIONS

Our findings showed no significant between-sex differences in clinical outcomes after receiving del Nido cardioplegia, suggesting adequate myocardial protection as currently administered. Further research is warranted to elicit if there are sex-based differences between cardioplegic solutions.

IRB APPROVAL DATE (PROTOCOL NUMBER)

26 May 2021 (AAAR8359).

External Support for Saphenous Vein Grafts in Coronary Artery Bypass Surgery: A Randomized Clinical Trial

Importance

Intimal hyperplasia and subsequent saphenous vein graft failure may have significant adverse clinical effects in patients undergoing coronary artery bypass surgery. External support of saphenous vein grafts has the potential to prevent vein graft dilation and hence slow the rate of intimal hyperplasia and increase long-term vein patency.

Objective

To determine efficacy, as measured by intimal hyperplasia, and safety of an external saphenous vein graft support device in patients undergoing a coronary bypass graft procedure.

Design, Setting, and Participants

This within-patient randomized, open-label, multicenter study was conducted at 17 Cardiothoracic Surgical Trials Network centers in North America. Between January 2018 and February 2019, 224 patients with multivessel coronary artery disease undergoing isolated bypass surgery were enrolled. For each patient, 1 of 2 vein grafts was randomized to receive external support or no support.

Interventions

External vein graft support or no support.

Main Outcomes and Measures

The primary efficacy end point was intimal hyperplasia area assessed by intravascular ultrasound at 12 months postrandomization for each study graft. Secondary confirmatory end points were lumen diameter uniformity assessed by angiography and graft failure (≥50% stenosis) by quantitative coronary angiography. Major cardiac and cerebrovascular events were collected through month 12.

Results

Among 224 patients (mean [SD] age, 65.8 [8.3] years; 178 [79.5%] male), 203 (90.6%) were eligible for intravascular ultrasound, of which 85 (41.9%) had at least 1 study graft occluded or severely diseased at 12 months (55 supported, 56 unsupported). After imputation of data missing because of graft occlusion or severe disease, the estimated mean (SE) intimal hyperplasia area was 5.11 (0.16) mm2 in supported grafts and 5.79 (0.20) mm2 in unsupported grafts (P = .07). In a sensitivity analysis of 113 patients with both grafts imaged, the mean intimal hyperplasia area was 4.58 (0.18) mm2 and 5.12 (0.23) mm2 in supported and unsupported grafts, respectively (P = .04). By 12 months, 5 patients (2.2%) died and 16 patients (7.1%) experienced a major cardiac or cerebrovascular event.

Conclusions and Relevance

The 12-month difference in intimal hyperplasia area between supported and unsupported grafts did not achieve statistical significance. Cumulative mortality and major cardiac or cerebrovascular events rates were similar to those in other randomized coronary artery bypass trials. Further investigation to assess the effect of external graft support devices on long-term graft patency and clinical outcomes is warranted.

Trial Registration

ClinicalTrials.gov Identifier: NCT03209609.

An opportunity to improve secondary prevention with icosapent ethyl in patients who have undergone coronary artery bypass graft surgery

INTRODUCTION

Icosapent ethyl reduces cardiovascular events in high-risk patients with hypertriglyceridaemia on statin therapy. However, it is not widely available and the potential application following coronary artery bypass graft (CABG) surgery is not well-established. We aimed to determine the real-world percentage of CABG surgery patients who may be eligible for the therapy.

METHODS

A retrospective analysis was performed between February 2015 and August 2020 in an Australian hospital. Patients were included if a lipid profile was performed at least three weeks following CABG surgery. Data was extracted from electronic medical records. Eligibility for icosapent ethyl was defined according to inclusion criteria from the REDUCE-IT trial.

RESULTS

Of 484 patients with follow-up lipid profiles, 21 (4.3%) were not eligible for icosapent ethyl based on age and 39 (8.1%) were not prescribed statin therapy or were prescribed a fibrate. After applying triglyceride and low-density lipoprotein cholesterol level criteria, 124 (25.6%) patients were potentially eligible for icosapent ethyl therapy. Of those eligible, high-intensity statin therapy were prescribed in 108 (87.1%).

DISCUSSION

A substantial percentage of CABG surgery patients may be eligible for icosapent ethyl and could potentially benefit from its cardiovascular protection. Further research should evaluate the additional cardiovascular benefits of icosapent ethyl in this very high-risk group of patients who are already treated with high-intensity statins.