Sex differences in hospital mortality after coronary artery bypass surgery: evidence for a higher mortality in younger 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.

Sex differences in patients presenting with acute coronary syndrome: a state-of-the-art review

Cardiovascular conditions in the spectrum of acute coronary syndromes are characterized by sex differences with regard to pathophysiology, risk factors, clinical presentation, invasive and pharmacologic treatment, and outcomes. This review delves into these differences, including specific subsets like myocardial infarction with non-obstructed coronary arteries or Spontaneous Coronary Artery Dissection, and alternative diagnoses like Takotsubo cardiomyopathy or myocarditis. Moreover, practical considerations are enclosed, on how a sex-specific approach should be integrated in clinical practice: in fact, personal history should focus on female-specific risk factors, and hormonal status and hormonal therapy should be assessed. Moreover, physical and psychological stressors should be investigated, particularly in the event of Spontaneous Coronary Artery Dissection or Takotsubo cardiomyopathy.

Age-specific sex-differences in cerebral blood flow velocity in relation to haemoglobin levels

INTRODUCTION

Cerebral blood flow (CBF) declines with age and abnormalities in CBF are associated with age-related cerebrovascular disease and neurodegeneration. Women have higher CBF than men, although this sex-difference diminishes to some extent with age in healthy subjects. The physiological drivers of these age/sex differences are uncertain, but might be secondary to age and sex-differences in haemoglobin (Hb) level. Hb levels are inversely correlated with CBF, are lower in women, and decline with age in men, but the interrelations between these factors have not been explored systematically either in healthy subjects or across the full age-range in patients with vascular risk factors. We aimed to determine the age-specific interrelations between sex, Hb, and CBF velocity in a large cohort of patients with cerebrovascular disease.

PATIENTS AND METHODS

In patients with a recent transient ischaemic attack or minor stroke (Oxford Vascular Study) and no ipsilateral or contralateral stenosis of the carotid or intracranial arteries, we related peak-systolic velocity (PSV) and other parameters on transcranial Doppler ultrasound (TCD) of the middle cerebral artery to sex, age, Hb and vascular risk factors.

RESULTS

Of 958 eligible subjects (mean age/SD = 68.04/14.26, 53.2% male), younger women (age < 55 years) had higher CBF velocities than men (mean sex difference in PSV at age < 55 years = 16.31 cm/s; p < 0.001), but this difference declined with age (interaction p < 0.001), such that it was no longer significant at age 75-84 (∆PSV = 3.26 cm/s; p = 0.12) and was reversed at age ⩾ 85 (∆PSV = -7.42 cm/s; p = 0.05). These changes mirrored trends in levels of Hb, which were higher in men at age < 55 (∆Hb = 1.92 g/dL; p < 0.001), but steadily decreased with age in men but not in women (interaction p < 0.001), with no residual sex-difference at age ⩾ 85 (∆Hb = 0.12 g/dL; p = 0.70). There was an inverse correlation between Hb and PSV in both women and men (both p ⩽ 0.01), and the sex-difference in PSV at age < 55 was substantially diminished after adjustment for Hb (∆PSV = 6.92; p = 0.036; ∆PSV = 5.92, p = 0.13 with further adjustment for end-tidal CO2). In contrast, the sex difference in PSV was unaffected by adjustment for systolic and diastolic blood pressure, heart rate, and vascular risk factors (history of hypertension, diabetes, hyperlipidaemia and smoking).

DISCUSSION

CBF velocity is strongly correlated with Hb level at all ages, and sex-differences in CBF velocity appear to be explained in major part by age-related sex-differences in Hb.

Sex Differences in Epidemiological Distribution and Outcomes of Surgical Mitral Valve Disease

BACKGROUND

Mitral valve (MV) disease is the most common form of valvular heart disease. Findings that indicate women have a higher risk for unfavorable outcomes than men remain controversial. This study aimed to determine the sex-based differences in epidemiological distributions and outcomes of surgery for MV disease.Methods and Results: Overall, 18,572 patients (45.3% women) who underwent MV surgery between 2001 and 2018 were included. Outcomes included in-hospital death and all-cause mortality during follow up. Subgroup analysis was conducted across different etiologies, including infective endocarditis (IE), degenerative, ischemic, and rheumatic mitral pathology. The overall MV repair rate was lower in women than in men (20.5% vs. 30.6%). After matching, 6,362 pairs (woman : man=1 : 1) of patients were analyzed. Women had a slightly higher risk for in-hospital death than men (10.8% vs. 9.8%; odds ratio [OR]: 1.11, 95% confidence interval [CI]: 0.99-1.24; P=0.075). Women tended to have a higher incidence of de novo dialysis (9.8% vs. 8.6%; P=0.022) and longer intensive care unit stay (8 days vs. 7.1 days; P<0.001). Women with IE had poorer in-hospital outcomes than men; however, there were no sex differences in terms of all-cause mortality.

CONCLUSIONS

Sex-based differences of MV intervention still persist. Although long-term outcomes were comparable between sexes, women, especially those with IE, had worse perioperative outcomes than men.

Sex-differences in outcome after off-pump coronary artery bypass grafting is age-dependent; data from the Netherlands Heart Registration

Background

Women are known to have worse outcome after coronary artery bypass grafting (CABG) than men. Studies have shown that off-pump coronary artery bypass grafting (OPCAB) might benefit higher-risk patients, and therefore might also benefit women. We aimed to determine differences in early and late outcomes between sexes after OPCAB.

Methods

Data from all patients undergoing OPCAB, between 2013 through 2021 was retrieved from the Netherlands Heart Registration (NHR) database. Primary outcomes were early mortality, morbidity and late survival. We divided the population into subgroups based on age (aged ≥70 years or < 70 years) and sex.

Results

This study included 8,487 men and 2,170 women (total = 10,657). Female patients received fewer anastomoses (mean (SD)) women 2.38 (1.17) vs men 2.68 (1.23), p < 0.001) and total arterial revascularization was performed less frequently in women than in men (21.3 % versus 29.5 % respectively, p < 0.001).In the subgroup of patients <70 years, early mortality was 1.7 % in women and 0.6 % in men (p < 0.001). Survival rate at 5 years was 88.4 % in women and 91.1 % in men (p < 0.001). Female sex was associated with worse late survival in the subgroup <70 years (HR (95 % CI) 1.42 (1.10-1.83) p = 0.008).

Conclusions

Sex-differences in outcome after CABG persists in OPCAB surgery. However, these differences are solely present in the younger subgroup. In our data, women undergoing OPCAB surgery seem to be treated differently during surgery as compared to their male counter parts, further research is needed to analyze this finding.

The Effect of Gender on Triple Heart Valve Surgery Outcomes; Reinforcing Women's Health

Female gender is a risk factor in several cardiac surgery risk stratification systems. This study explored the differences in the outcomes following triple heart valve surgery in men vs women. The study included 250 patients (males n = 101; females n = 149) who underwent triple valve surgery from 2009 to 2020. BMI (body mass index) was higher in females (29.6 vs 26.5 kg/m2, P < .001), and diabetes was more common in males (44 vs 42%, P = .012). The ejection fraction was higher in females (55 vs 50%, P < .001). The severity of mitral valve stenosis and tricuspid valve regurgitation was significantly greater in females (33.11 vs 27.72%, P = .003 and 44.30 vs 19.8%, P < .001, respectively). Mitral valve replacement was more common in females (P < .001), and they had lower concomitant coronary artery bypass grafting (P = .001). Bleeding and renal failure were lower in females (P = .021 and <0.001, respectively). Hospital mortality, readmission, and reintervention were not significantly different between genders. By multivariable analysis, male gender was a risk factor for lower survival [HR (hazard ratio): 2.18; P = .024]. Triple valve surgery can be performed safely in both genders, with better long-term survival in females. Female gender was not a risk factor in patients undergoing triple valve surgery.

Concomitant Valve Replacement and Coronary Artery Bypass Grafting Surgery: Lessons from the Past, Guidance for the Future? A Mortality Analysis in 294 Patients

OBJECTIVE

The aims of this study were to analyze parameters influencing early and late mortality after concomitant valve replacement and coronary artery bypass grafting surgery, using early and long-term information from an institutionally available data registry, and to discuss the results in relation to the current treatment strategies and perspectives.

METHODS

The study population consisted of 294 patients after combined valve replacement with mechanical prosthesis and CABG surgery.

RESULTS

There were 201 men (68.4%) and 93 women (31.6%). Concurrent to the coronary artery bypass grafting, 238 patients (80.9%) underwent aortic-, 46 patients (15.6%) mitral- and 10 patients (3.4%) doublevalve replacement. Cumulative duration of follow up was 1007 patient-years (py) with a maximum of 94 months and was completed in 92.2% (271 cases). Overall hospital mortality (30 days) rate was 6.5% (n = 19). It was significantly higher in patients of female gender, older than 70 y, in those suffering preoperative myocardial infarction, presenting with an additive EuroScore > 8 and being hemodynamically unstable after the operation. Cumulative survival rate at 7.6 y was 78.6%. Determinants of prolonged survival were male gender, age at operation < 70 y, preoperative sinus rhythm, normal renal function, additive EuroScore < 8 and the use of internal thoracic artery for grafting. Subsequent multivariate analysis revealed preoperative atrial fibrillation (HR: 2.1, 95% CI: 0.82-5.44, p: 0.01) and risk group of ES > 8 (HR: 3.63, 95% CI: 1.45-9.07, p < 0.01) as independent predictors for lower long-term survival.

CONCLUSIONS

Hospital mortality (30 d) was nearly 2.5-fold higher in female and/or older than 70 y patients. Preoperative atrial fibrillation and/ or a calculated ES > 8 were independent predisposing factors of late mortality for combined VR and CABG surgery. Tailoring the approach, with the employment of the newest techniques and hybrid procedures, to the individual patient clinical profile enables favorable outcomes for concomitant valvular disease and CAD, especially in high-risk patients.

Impact of Bariatric Surgery on Mortality of Mitral Valve Surgery: A National Analysis

OBJECTIVE

Obesity is a common comorbidity of cardiac surgery patients. The goal of this study is to determine if a lower weight achieved through bariatric surgery has any association with mitral valve (MV) replacement or repair surgery mortality.

METHODS

This study used a retrospective analysis of the National Inpatient Sample dataset from 2012 to 2020. Adult patients who underwent MV surgery with normal weight following bariatric surgery (n = 1,125) and patients with obesity (n = 48,555) were compared. The primary outcome was in-hospital mortality.

RESULTS

This study included 49,680 patients. The median age was 64 (55 to 71) years, and the majority were female (55%). Bariatric surgery was found to significantly decrease the odds of mortality, even after adjusting for important covariates, indicating a reduction of mortality risk by 54% (adjusted odds ratio = 0.46, p = 0.024). Other significant protective factors include isolated and elective surgery. Significant risk factors were older age, female sex, and diabetes mellitus. Patients who were obese demonstrated longer lengths of stay (LOS), greater transfers to other facilities, and higher hospital costs.

CONCLUSIONS

In patients receiving MV surgery, bariatric surgery demonstrated significant survival benefits during hospitalization, in addition to reducing LOS and cost. Our data support prior evidence of bariatric surgery improving cardiovascular outcomes. Therefore, bariatric surgery may be a meaningful method of weight loss to improve surgical patient outcomes in patients with obesity. However, longer-term data are needed.

Predictors of outcomes in patients with obesity following mitral valve surgery

Objective

Few studies have assessed the outcomes of mitral valve surgery in patients with obesity. We sought to study factors that determine the in-hospital outcomes of this population to help clinicians provide optimal care.

Methods

A retrospective analysis of adult patients with obesity who underwent open mitral valve replacement or repair between January 1, 2012, and December 31, 2020, was conducted using the National Inpatient Sample. Weighted logistic regression and random forest analyses were performed to assess factors associated with mortality and the interaction of each variable.

Results

Of the 48,775 patients with obesity, 34% had morbid obesity (body mass index ≥40), 55% were women, 66% underwent elective surgery, and 55% received isolated open mitral valve replacement or repair. In-hospital mortality was 5.0% (n = 2430). After adjusting for important covariates, a greater risk of mortality was associated with older patients (adjusted odds ratio [aOR], 1.24; 95% CI, 1.08-1.43), higher Elixhauser comorbidity score (aOR, 2.10; 95% CI, 1.87-2.36), prior valve surgery (aOR, 1.63; 95% CI, 1.01-2.63), and more than 2 concomitant procedures (aOR, 2.83; 95% CI, 2.07-3.85). Lower mortality was associated with elective admissions (aOR, 0.70; 95% CI, 0.56-0.87) and valve repair (aOR, 0.58; 95% CI, 0.46-0.73). Machine learning identified several interactions associated with early mortality, such as Elixhauser score, female sex, body mass index ≥40, and kidney failure.

Conclusions

The complexity of presentation, comorbidities in older and female patients, and morbid obesity are independently associated with an increased risk of mortality in patients undergoing open mitral valve replacement or repair. Morbid obesity and sex disparity should be recognized in this population, and physicians should consider older patients and females with multiple comorbidities for earlier and more opportune treatment windows.

Gender medicine: effects of sex and gender on cardiovascular disease manifestation and outcomes

Despite a growing body of evidence, the distinct contributions of biological sex and the sociocultural dimension of gender to the manifestations and outcomes of ischaemic heart disease and heart failure remain unknown. The intertwining of sex-based differences in genetic and hormonal mechanisms with the complex dimension of gender and its different components and determinants that result in different disease phenotypes in women and men needs to be elucidated. The relative contribution of purely biological factors, such as genes and hormones, to cardiovascular phenotypes and outcomes is not yet fully understood. Increasing awareness of the effects of gender has led to efforts to measure gender in retrospective and prospective clinical studies and the development of gender scores. However, the synergistic or opposing effects of sex and gender on cardiovascular traits and on ischaemic heart disease and heart failure mechanisms have not yet been systematically described. Furthermore, specific considerations of sex-related and gender-related factors in gender dysphoria or in heart-brain interactions and their association with cardiovascular disease are still lacking. In this Review, we summarize contemporary evidence on the distinct effects of sex and gender as well as of their interactions on cardiovascular disease and how they favourably or unfavourably influence the pathogenesis, clinical manifestations and treatment responses in patients with ischaemic heart disease or heart failure.

Prediction of Male Coronary Artery Bypass Grafting Outcomes Using Body Surface Area Weighted Left Ventricular End-diastolic Diameter: Multicenter Retrospective Cohort Study

BACKGROUND

The presence of a high left ventricular end-diastolic diameter (LVEDD) has been linked to a less favorable outcome in patients undergoing coronary artery bypass grafting (CABG) procedures. However, by taking into consideration the reference of left ventricular size and volume measurements relative to the patient's body surface area (BSA), it has been suggested that the accuracy of the predicting outcomes may be improved.

OBJECTIVE

We propose that BSA weighted LVEDD (bLVEDD) is a more accurate predictor of outcomes in patients undergoing CABG compared to simply using LVEDD alone.

METHODS

This study was a comprehensive retrospective cohort study that was conducted across multiple medical centers. The inclusion criteria for this study were patients who were admitted for treatment between October 2016 and May 2021. Only elective surgery patients were included in the study, while those undergoing emergency surgery were not considered. All participants in the study received standard care, and their clinical data were collected through the institutional registry in accordance with the guidelines set forth by the Society of Thoracic Surgeons National Adult Cardiac Database. bLVEDD was defined as LVEDD divided by BSA. The primary outcome was in-hospital all-cause mortality (30 days), and the secondary outcomes were postoperative severe adverse events, including use of extracorporeal membrane oxygenation, multiorgan failure, use of intra-aortic balloon pump, postoperative stroke, and postoperative myocardial infarction.

RESULTS

In total, 9474 patients from 5 centers under the Chinese Cardiac Surgery Registry were eligible for analysis. We found that a high LVEDD was a negative factor for male patients' mortality (odds ratio 1.44, P<.001) and secondary outcomes. For female patients, LVEDD was associated with secondary outcomes but did not reach statistical differences for morality. bLVEDD showed a strong association with postsurgery mortality (odds ratio 2.70, P<.001), and secondary outcomes changed in parallel with bLVEDD in male patients. However, bLVEDD did not reach statistical differences when fitting either mortality or severer outcomes in female patients. In male patients, the categorical bLVEDD showed high power to predict mortality (area under the curve [AUC] 0.71, P<.001) while BSA (AUC 0.62) and LVEDD (AUC 0.64) both contributed to the risk of mortality but were not as significant as bLVEDD (P<.001).

CONCLUSIONS

bLVEDD is an important predictor for male mortality in CABG, removing the bias of BSA and showing a strong capability to accurately predict mortality outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02400125; https://clinicaltrials.gov/ct2/show/NCT02400125.

The Gamut of Coronary Artery Disease in Indian Women

Coronary artery disease is the leading cause of death among women. Majority of women suffering from CAD have one or more risk factors for CAD in their parents. Women are at higher risk for cardiac events with respect to traditional risk factors including dyslipidemia, hypertension, diabetes, and smoking. Menopause, pregnancy complications, inflammation, anemia, migraines, and depression are important sex-specific novel risk factors for CVD, and it is important that clinicians should be aware of these risks to design strategies for prevention. Education, self-awareness in women, and timely recognition of CAD in women with lifestyle modifications and timely intervention result in better outcomes.

Sex differences in coronary artery bypass grafting-related morbidity and mortality

Background

Coronary artery bypass grafting (CABG) is associated with both cardiovascular disease (CVD) and non-CVD traits. In addition, women’s prognosis after coronary events and revascularizations is worse than in men. As the course of CVD in women differs from that of men, we performed a phenome-wide analysis on the sex differences in CABG -related morbidity and mortality.

Materials and methods

We performed an untargeted analysis on the sex differences in predictors and outcomes of CABG. We studied a sample of 176,680 FinnGen participants, including 5,950 individuals who underwent CABG (4,988 men and 962 women) and were followed between 1998 and 2019. Over 1,100 different traits were analyzed for both sexes and the results were adjusted with age, smoking status and BMI. Cox proportional hazards models with sex-trait interactions were used to estimate the associations between (1) traits and incident CABG; and (2) CABG and incident traits.

Results

In women, CABG was more strongly related to greater increases in risk of diseases such as hypertension, Alzheimer’s, aortic aneurysms, gout, and chronic kidney disease compared to risk increases observed in men (all interaction p-values &lt; 0.03). After CABG, men had 2.5-fold (p = 3.1E−15) and women 6.3-fold (p = 9.4E−08) greater risk of cardiac death compared to same-sex individuals who did not undergo CABG (p for interaction 8.2E−4). Moreover, the risk of death in women remained higher even 12 years after CABG, whereas the long-term risk of death in men was not increased, compared to same-sex individuals who did not undergo CABG.

Conclusion

The adverse outcomes after CABG, both quantity and quality, also appear to differ between men and women. In women, CABG is related to greater long-term increases in risk of cardiac death and several other disease states than in men. Consideration should therefore be given to whether women receive adequate long-term post-operative therapy and follow-up as CABG is not associated with equally improved cardiovascular disease prognosis in women than in men.

Gender Specific Coronary Artery Diameters in CT Coronary Angiogram: A Comparative Study in Female and Male Population

Objectives:

Women show significant in-hospital morbidity and mortality with greater extent of symptoms, poorer post-revascularization outcome with increased restenosis and repeat revascularization after angioplasty, than men. Smaller sized coronary arteries in females can be attributable for this differential outcome, which is also similar in case of Indians, compared to Caucasians. Our aim is to assess the gender-specific difference in coronary arteries using noninvasive Multidetector Computed-Tomography Coronary-Angiogram(CT-CAG) and comparing the same with other racial database.

Materials and Methods:

With Ethics committee approval, present retrospective comparative study conducted in 128CT-CAG scans in 18-45years aged 100 women and 89 men with no atherosclerotic burden excluding pathological coronaries and high calcium score>100. Diameter measurements of proximal (≤10mm) segments of right coronary artery(RCA), left main coronary artery(LMCA), left anterior descending(LAD) and circumflex(LCx) arteries were taken, averaged and compared using 2-sample z-test. Considering the obtained mean diameters of total sample as South-Indian dataset which is then compared with Caucasians dataset taken from previous study.

Results:

Women showed smaller coronary artery diameters compared to men in all the arteries, with greater gender-specific age-adjusted difference in LMCA, followed by LAD, RCA and least in LCX. South-Indians showed statistically significant smaller diameters of all the coronary arteries compared to Caucasians.

Conclusion:

Gender-specific difference among the coronary arteries does exist, with females having smaller dimensions; South-Indians also show smaller diameters. This warrants a clinician for gender-specific approaches during the interventions because of technical difficulties.

Inclusion of Under-Represented Racial and Ethnic Groups in Cardiovascular Clinical Trials

INTRODUCTION

Non-White racial and ethnic groups have been traditionally under-represented for decades in the field of cardiology, specifically in cardiovascular research studies. This underrepresentation has occurred despite the fact that these racial and ethnic groups have been shown to be at increased risk of cardiovascular disease (CVD).

METHODS

To assess the trend of representation in mainstream landmark cardiovascular trials, we performed a review of major cardiovascular trials published between 1986 and 2019. Mainstream landmark trials were selected as classified by established cardiology standards. The reported numbers of racial and ethnic participants were assessed within these categorised cardiovascular trials over a continuous time period.

RESULTS

A total of 1,138,683 patients were assessed from 153 randomised clinical trials. Of these trials, only 56% (n=86) reported information about race. Of note, 99% (n=152) of these trials reported gender. About three-quarters of the trials (77%) were undertaken at least partly in the United States (US). Our results show that the percentage of non-White participants in clinical trials was not significantly different over time (p=0.85), suggesting no significant improvement in non-White racial/ethnic representation. Further analysis of only the US inclusive trials (n=20) also showed no significant improvement in representation (p=0.38).

CONCLUSION

Only about half of all major cardiovascular landmark trials reported any racial or ethnic information, despite more recent calls over the last 5-10 years for diversity and representation in cardiovascular research studies. Additionally, no significant improvement in inclusion of traditionally under-represented racial and ethnic groups (UREGs) in these trials has occurred over time. Our analysis shows that there is still major work to be done to foster better representation and evaluation of the UREG population in cardiovascular trials.

Sex-Specific Associations of Diabetes With Brain Structure and Function in a Geriatric Population

Introduction

Globally, women with dementia have a higher disease burden than men with dementia. In addition, women with diabetes especially are at higher risk for cognitive impairment and dementia compared to men with diabetes. Differences in the influence of diabetes on the cerebral vasculature and brain structure may contribute to these sex-specific differences. We examined sex-specific patterns in the relationship between diabetes and brain structure, as well as diabetes and cognitive function.

Methods

In total, 893 patients [age 79 ± 6.6 years, 446 (50%) women] from the Amsterdam Ageing Cohort with available data on brain structures (assessed by an MRI or CT scan) and cognitive function were included. All patients underwent a thorough standardized clinical and neuropsychological assessment (including tests on memory, executive functioning, processing speed, language). Brain structure abnormalities were quantified using visual scales.

Results

Cross-sectional multivariable regression analyses showed that diabetes was associated with increased incidence of cerebral lacunes and brain atrophy in women (OR 2.18 (1.00–4.72) but not in men. Furthermore, diabetes was associated with decreased executive function, processing speed and language in women [B −0.07 (0.00–0.13), −0.06 (0.02–0.10) and −0.07 (0.01–0.12) resp.] but not in men.

Conclusions

Diabetes is related to increased risk of having lacunes, brain atrophy and impaired cognitive function in women but not in men. Further research is required to understand the time trajectory leading up to these changes and to understand the mechanisms behind them in order to improve preventive health care for both sexes.

The impact of age and sex on in-hospital outcomes in acute type A aortic dissection surgery

Background

Older age and female sex are thought to be risk factors for adverse outcomes after repair of acute type A aortic dissection (AAAD). The aim of this study is to analyze age- and sex-related outcomes in patients undergoing AAAD repair.

Methods

Retrospective analysis of patients undergoing emergency AAAD repair. Patients were divided in Group A, patients aged ≥75 years and Group B <75. Intraoperative and postoperative data were compared between groups before and after propensity score matching. Sex differences were analyzed by age group.

Results

Between January 2006 and December 2018, 638 patients underwent emergency AAAD repair. Group A included 143 patients (22.4%), Group B 495 (77.6%). More patients in Group A presented with circulatory collapse (Penn C 26.6% vs. 9.7%, P=0.001) while Group B presented with circulatory collapse-branch malperfusion (Penn BC 29.3% vs. 15.4% P=0.001). After propensity score matching, Group B patients received more complex aortic root (33.6% vs. 23.2%, P=0.019) and concomitant bypass surgery (12.3% vs. 6.3%, P=0.042). There was no significant difference in in-hospital mortality between age groups (18% vs. 12% P=0.12). In Group B, in-hospital mortality was significantly higher in females (22.2% vs. 8.2%, P=0.028). Differences in mortality disappeared after the age of 75 (18.3% vs. 19.4% P=0.87).

Conclusions

Morbidity and mortality are comparable between patients under and over 75 years after AAAD repair. Female patients <75 had higher in-hospital mortality than their male counterparts.

Impact of gender differences on hemostasis in patients after coronary artery bypass grafts surgeries in the context of tranexamic acid administration

BACKGROUND

Sex differences present in the blood management of patients after coronary artery bypass grafts (CABG) surgeries. Tranexamic acid (TXA) performed well in maintaining hemostasis during and after surgeries. However, the impact of sex differences on blood control after CABG in patients who received TXA was not investigated.

METHODS

Overall, 29,536 patients undergoing CABG with TXA administration from 2009 to 2019 in our hospital were included. Propensity score matching was performed. Finally, 6808 males and 6808 females were matched based on 23 covariates.

RESULTS

Female patients had a 0.36-fold lower incidence of reoperations due to major hemorrhage or cardiac tamponade compared to males (1.3% vs. 2.0%, p = 0.001, OR = 0.64, 95%CI = 0.49-0.84). Females had a median of 100 ml less blood loss in 24 h (median 360 vs. 460 ml, p < 0.0001), 150 ml less in 48 h (median 580 vs. 730 ml, p < 0.0001), and 180 ml less in total (median 760 vs. 940 ml, p < 0.0001) than male patients. The red blood cell (RBC) transfusion rate in female was 1.53-fold higher than that in male (33.0% vs. 21.6%, OR = 1.53, 95% CI = 1.43-1.63, p < 0.0001). Females also had higher morbidities than males after CABGs.

CONCLUSIONS

Females had less blood loss than males after CABG with the TXA treatment. Females still had a higher RBC transfusion rate after surgery. Morbidities in women were also higher than that in men.

Sex differences in risks of in-hospital and late outcomes after cardiac surgery: a nationwide population-based cohort study

OBJECTIVES

Outcomes of sex differences in major cardiac surgery remain controversial. A comprehensive understanding of sex differences in major adult cardiac surgery could provide better knowledge of risk factors, management strategy and short-term or long-term outcomes. The present study aimed to investigate sex differences in the risks of outcomes of major cardiac surgeries and subgroup analyses of different valve types.

DESIGN

Population-based nationwide cohort study.

SETTING

Data were obtained from National Health Insurance Research Database (NHIRD) in Taiwan.

PARTICIPANTS

A total of 66 326 adult patients (age ≥20 years; 30.3% women) who underwent a first major cardiac surgery (isolated coronary artery bypass graft (CABG), isolated valve or concomitant bypass/valve) from 2000 to 2013 were identified via Taiwan NHIRD.

MAIN OUTCOME MEASURES

Outcomes of primary interest were in-hospital death and all-cause mortality during follow-up period. Propensity score matching was conducted as a secondary analysis for the sensitivity test.

RESULTS

Women who underwent isolated CABG tended to have greater risks of both in-hospital (OR 1.37; 95% CI 1.26 to 1.49) and late outcomes (HR 1.26; 95% CI 1.22 to 1.31). Women after concomitant CABG/valve also had a greater in-hospital (OR 1.19; 95% CI 1.01 to 1.40) and long-term mortality (HR 1.14; 95% CI 1.05 to 1.24). Women after isolated mitral valve repair have a non-favourable outcome of in-hospital mortality (OR 1.70; 95% CI 1.01 to 2.87). Women who did not receive an isolated aortic valve replacement had more favourable all-cause mortality outcome (HR 0.90; 95% CI 0.84 to 0.96). Secondary analysis in the propensity score-matching cohort demonstrated results similar to the primary analysis.

CONCLUSIONS

Female patients who underwent procedures involving CABG (with or without concurrent valvular intervention) had generally worse outcomes. However, the results of isolated valve surgery were variable on the basis of the type of intervened valve.

Average Exercise Capacity in Men and Women >75 Years of Age Undergoing a Bruce Protocol Exercise Stress Test

Exercise stress testing is routinely performed to evaluate suspected coronary artery disease in older adults. However, the available data to predict and compare relative exercise capacity in the general population were developed using predominantly younger, healthy cohorts with few or no women. This study aimed to describe the exercise capacity of patients older than 75 years who underwent a clinically indicated Bruce protocol exercise stress test. This was a retrospective, cross-sectional study of 2,041 consecutive patients older than 75 years who performed a Bruce protocol exercise stress echocardiogram that was terminated because of maximal effort without ischemia at Columbia University Medical Center between April 10, 2009, and July 30, 2020. The analytic sample included 2,041 exercise stress tests in 786 women (median [interquartile range] age 79 [77 to 81] years) and 1,255 men (median [interquartile range] age 79 [77 to 82] years). Cardiovascular risk factors and clinical coronary disease were common and more prevalent in men than women. The median exercise time for men aged 76 to 80 years was 7:22 (minutes:seconds) and for women was 6:00 and significantly decreased in both genders as age increased (p <0.001). The mean (SD) METs achieved for women and men were 6.5 (1.6) and 7.7 (1.7), respectively. Most women (85%) and men (95%) completed the first stage, whereas only 32% of women and 64% of men completed the second stage. It was uncommon for women (3%) or men (15%) to complete the third stage. Fewer than 1% of patients completed the fourth stage, and none completed the fifth stage. At all ages, women had a lower exercise capacity than men. These data allow physicians to compare the exercise capacity of older patients who underwent a Bruce protocol exercise stress test more accurately to a representative sample of similarly aged adults.

The Association Between Acute Kidney Injury and Mortality After Coronary Artery Bypass Grafting Was Similar in Women and Men

OBJECTIVE

To assess sex differences in short- and long-term mortality in patients who develop acute kidney injury (AKI) after coronary artery bypass grafting (CABG).

DESIGN

An observational cohort study.

SETTING

A multicenter, nationwide, population-based, observational cohort study.

PARTICIPANTS

All patients (n = 32,013) who underwent primary nonemergent isolated CABG in Sweden between January 1, 2003, and December 31, 2013.

INTERVENTIONS

AKI and its association with 90-day mortality were analyzed using logistic regression. AKI and its association with long-term mortality were analyzed using Cox regression analysis.

MEASUREMENTS AND MAIN RESULTS

AKI was defined as an absolute increase by 26 µmol/L or a relative increase by 50% postoperatively compared with the preoperative serum creatinine concentration. Ninety-day mortality was defined as death by any cause within 90 days after surgery. Long-term mortality was defined as death by any cause from day 91 after surgery to the end of the study period. In total, 13.9% of women and 14.4% of men developed AKI after CABG. The multivariate-adjusted odds ratio (95% confidence interval [CI]) for death within 90 days in patients with AKI compared to those without AKI was 5.1 (3.6-7.2) and 5.2 (4.2-6.6) in women and men, respectively (p for interaction = 0.74). The multivariate-adjusted hazard ratio (95% CI) for long-term death in those with AKI compared to those without AKI was 1.4 (1.2-1.7) and 1.3 (1.2-1.4) in women and men, respectively (p for interaction = 0.27).

CONCLUSION

AKI after CABG was associated with a similar increase in 90-day and long-term mortality in both women and men.

Impact of sex on outcomes after cardiac surgery: A systematic review and meta-analysis

BACKGROUND

Despite advances in cardiac surgery, observational studies suggest that females have poorer post-operative outcomes than males. This study is the first to review sex related outcomes following both coronary artery bypass graft (CABG) and valve surgery with or without combined CABG.

METHODS

We identified 30 primary research articles reporting either short-term mortality (in-hospital/30 day), long-term mortality, and post-operative stroke, sternal wound infection and myocardial infarction (MI) in both sexes following CABG and valve surgery with or without combined CABG. Reported adjusted odds/hazard ratio were pooled using an inverse variance model.

RESULTS

Females undergoing CABG and combined valve and CABG surgery were at higher risk of short-term mortality (odds ratio (OR) 1.40; 95% confidence interval (CI) 1.32-1.49; I² = 79%) and post-operative stroke (OR 1.2; CI 1.07-1.34; I² = 90%) when compared to males. However, for isolated AVR, there was no difference found (OR 1.19; 95% CI 0.74-1.89). There was no increased risk in long-term mortality (OR 1.04; 95% CI: 0.93-1.16; I² = 82%), post-operative MI (OR 1.22; 95%CI: 0.89-1.67; I² = 60%) or deep sternal wound infection (OR 0.92; 95%CI: 0.65-1.03, I² = 87%). No evidence of publication bias or small study effect was found.

CONCLUSION

Females are at a greater risk of short-term mortality and post-operative stroke than males following CABG and valve surgery combined with CABG. However, there is no difference for Isolated AVR. Long-term mortality is equivalent in both sexes. PROSPERO Registration: CRD42021244603.

Coronary Artery Disease in Women: A Comprehensive Appraisal

Coronary artery disease (CAD) is a significant cause of illness and death amongst women. The pathophysiology, manifestations, and outcomes of CVD and CAD differ between sexes. These sex differences remain under-recognized. The aim of this review is to highlight and raise awareness of the burden and unique aspects of CAD in women. It details the unique pathophysiology of CAD in women, cardiovascular risk factors in women (both traditional and sex-specific), the clinical presentation of CAD in women, and the range of disease in obstructive and non-obstructive CAD in women.

Update: Gender differences in CABG outcomes-Have we bridged the gap?

Background

Appreciation of unique presentation, patterns and underlying pathophysiology of coronary artery disease in women has driven gender based risk stratification and risk reduction efforts over the last decade. Data regarding whether these advances have resulted in unequivocal improvements in outcomes of CABG in women is conflicting. The objective of our study was to assess gender differences in post-operative outcomes following CABG.

Methods

Retrospective analyses of institutional data housed in the Society of Thoracic Surgeons (STS) database for patients undergoing CABG between 2002 and 2020 were conducted. Multivariable regression analysis was conducted to investigate gender differences in post-operative outcomes. P-values were adjusted using Bonferroni correction to reduce type-I errors.

Results

Our final cohort of 6,250 patients had fewer women than men (1,339 vs. 4,911). more women were diabetic (52.0% vs. 41.2%, p<0.001) and hypertensive (89.1% vs. 84.0%, p<0.001). Women had higher adjusted odds of developing ventilator dependence >48 hours (OR: 1.65 [1.21, 2.45], p = 0.002) and cardiac readmissions (OR: 1.56 [1.27, 2.30], p = 0.003). After adjustment for comorbidity burden, mortality rates in women were comparable to those of age-matched men.

Conclusion

The findings of our study indicate that despite apparent reduction of differences in mortality, the burden of postoperative morbidity is still high among women.

Trends in Characteristics and Outcomes of Hospitalized Young Patients Undergoing Coronary Artery Bypass Grafting in the United States, 2004 to 2018

Background

Data are limited about young adults' characteristics and outcomes undergoing coronary artery bypass grafting (CABG).

Methods and Results

We used the National Inpatient Sample database to identify adults aged 18 to 45 years who underwent CABG between 2004 and 2018. The data were weighted to generate national estimates of the entire US hospitalized population. We identified 110 463 CABG cases, equivalent to 62.2 per 1 000 000 person‐years; 27.1% were women, and 70.2% were White adults. Overall, annual CABG volume per 1 000 000 significantly decreased from 87.3 in 2004 to 45.7 in 2018. The prevalence of obesity, diabetes mellitus, hypertension, drug abuse, and chronic medical conditions increased over time. Overall, inpatient mortality was 1.76%; ST‐segment–elevation myocardial infarction, non–ST‐segment–elevation myocardial infarction, heart failure, peripheral vascular disease, renal failure, and valvular surgery were associated with higher inpatient mortality. Women had higher inpatient mortality than men (2.29% versus 1.57%), and Black patients had higher deaths than White patients (2.86% versus 1.58%). Inpatient mortality remained stable overall, according to sex, race, or clinical indication of CABG. However, the mean length of stay (8.4 days in 2004 to 9.5 days in 2018) and inflation‐adjusted cost of care ($40 522.8 in 2004 to $52 434.2 in 2018) significantly increased during the study period.

Conclusions

Despite the increased burden of cardiometabolic risk factors, the inpatient mortality in young adults undergoing CABG remained stable during the last 15 years. However, CABG volumes have decreased, but length of stay and inflation‐adjusted costs have increased over time.

Sex Difference in Long-Term Survival After Coronary Artery Bypass Grafting Is Age-Dependent

OBJECTIVES

Women undergoing coronary artery bypass grafting (CABG) demonstrate higher rates of postoperative morbidity and mortality than men. The aim of this study was to compare the patient profile and long-term outcomes of men and women undergoing isolated CABG.

DESIGN

A retrospective patient record study and propensity score-matched analysis.

SETTING

This single-center study was performed at Catharina Hospital in Eindhoven, The Netherlands.

PARTICIPANTS

The study comprised 17,483 patients, of whom 13,564 (77.6%) were men and 3,919 (22.4%) were women.

INTERVENTIONS

Coronary artery bypass grafting was performed between January 1998 and December 2015.

MEASUREMENTS AND MAIN RESULTS

The mean follow-up period was 8.8 ± 5.0 years. Women were older than men (67.7 ± 9.4 years v 63.9 ± 9.6 years, p < 0.001) and had lower preoperative hemoglobin levels. Early mortality (30-day) (2.8% v 1.9%; p < 0.001) and one-year mortality (5.2% v 3.8%; p < 0.001) rates were significantly higher in women than in men. Women demonstrated worse long-term survival than men only in the population younger than 70 years. After propensity score matching, female sex was not identified as an independent risk factor for long-term survival.

CONCLUSIONS

In the patient population, propensity score-matched analysis showed that female sex was not an independent risk factor for long-term survival after CABG. Poorer survival in women after CABG only was observed in patients <70 years of age.

Managing Ischemic Heart Disease in Women: Role of a Women's Heart Center

PURPOSE OF REVIEW

Heart centers for women (HCW) were developed due to the rising cardiovascular morbidity and mortality in women in the United States in the early 1990s. Our review encompasses the epidemiology, risk factors, diagnostic strategies, treatments, and the role of HCW in managing women with ischemic heart disease (IHD).

RECENT FINDINGS

HCW use a multidisciplinary team to manage women with IHD. Due to the paucity of randomized controlled trials investigating various manifestations of IHD, some treatments are not evidence-based such as those for coronary microvascular dysfunction and spontaneous coronary artery dissection. Sex-specific risk factors have been identified and multimodality cardiac imaging is improving in diagnosing IHD in women. Treatments are being studied to help improve symptoms and outcomes in women with IHD. There has been progress in the care of women with IHD. HCW can be instrumental in treating women with IHD, doing research, and being a source of research study participants.

Sex differences in outcomes after coronary artery bypass grafting: a pooled analysis of individual patient data

AIMS

Data suggest that women have worse outcomes than men after coronary artery bypass grafting (CABG), but results have been inconsistent across studies. Due to the large differences in baseline characteristics between sexes, suboptimal risk adjustment due to low-quality data may be the reason for the observed differences. To overcome this limitation, we undertook a systematic review and pooled analysis of high-quality individual patient data from large CABG trials to compare the adjusted outcomes of women and men.

METHODS AND RESULTS

The primary outcome was a composite of all-cause mortality, myocardial infarction (MI), stroke, and repeat revascularization (major adverse cardiac and cerebrovascular events, MACCE). The secondary outcome was all-cause mortality. Multivariable mixed-effect Cox regression was used. Four trials involving 13 193 patients (10 479 males; 2714 females) were included. Over 5 years of follow-up, women had a significantly higher risk of MACCE [adjusted hazard ratio (HR) 1.12, 95% confidence interval (CI) 1.04-1.21; P = 0.004] but similar mortality (adjusted HR 1.03, 95% CI 0.94-1.14; P = 0.51) compared to men. Women had higher incidence of MI (adjusted HR 1.30, 95% CI 1.11-1.52) and repeat revascularization (adjusted HR 1.22, 95% CI 1.04-1.43) but not stroke (adjusted HR 1.17, 95% CI 0.90-1.52). The difference in MACCE between sexes was not significant in patients 75 years and older. The use of off-pump surgery and multiple arterial grafting did not modify the difference between sexes.

CONCLUSIONS

Women have worse outcomes than men in the first 5 years after CABG. This difference is not significant in patients aged over 75 years and is not affected by the surgical technique.

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

BACKGROUND

Females with coronary artery disease (CAD) have inferior outcomes compared with males, including higher mortality following coronary artery bypass grafting (CABG). We aimed to evaluate the association of female sex with the use of guideline-concordant CABG revascularization techniques.

METHODS

The Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database was queried for adult patients who underwent first-time isolated CABG in the US from 2011-2019. The association between female sex and the odds of (1) receiving a left internal mammary artery (LIMA) graft for revascularization of the left anterior descending (LAD) artery, (2) undergoing complete revascularization, and (3) undergoing multi-arterial grafting was assessed, adjusting for procedural anatomy.

RESULTS

Among 1,212,487 patients meeting inclusion criteria, 75% were male (n=911,178) and 25% were female (n=301,309). Female sex was associated with lower unadjusted rates of revascularization with an IMA (93.9% vs 95.9%, P<.001), bilateral IMA (2.9% vs 5.6%, P<.001) or radial artery (3.2% vs 5.6%, P<.001) graft. After adjustment, females had a lower odds than males of receiving a LIMA graft to the LAD (adjusted odds ratio [AOR] 0.79, 95% CI 0.75-0.83, P<.001), undergoing complete revascularization (AOR 0.86, 95% CI 0.83-0.90, P<.001), and undergoing multi-arterial grafting (AOR 0.78, 95% CI 0.75-0.81, P<.001).

CONCLUSIONS

Female sex was associated with a 14-22% lower odds of undergoing guideline concordant revascularization including LIMA to LAD grafting, multi-arterial grafting, and complete revascularization. Further investigation is necessary to determine why revascularization approaches differ by sex and to what degree sex disparities in CAD outcomes are due to surgical approach.

Early systolic lengthening by speckle tracking echocardiography predicts outcome after coronary artery bypass surgery

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Early systolic lengthening (ESL) is a paradoxical lengthening of myocardial fibers.

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Speckle tracking echocardiography is a common imaging tool for assessment of ESL.

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ESL was a predictor of cardiovascular and all-cause death in CABG patients.

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Specifically, the prognostic value of ESL was enhanced in women undergoing CABG.

Background

Early systolic lengthening (ESL), a paradoxical stretch of myocardial fibers, has been linked to loss of myocardial viability and contractile dysfunction. We assessed the long-term prognostic potential of ESL in coronary artery bypass graft (CABG) patients.

Methods

We retrospectively included patients (n = 709; mean age 68 years; 85% men) who underwent speckle tracking echocardiography (median 15 days) prior to CABG. Endpoints were cardiovascular death (CVD) and all-cause mortality. We assessed amplitude of ESL (%), defined as peak positive strain, and duration of ESL (ms), determined as time from Q-wave on the ECG to peak positive strain. We applied Cox models adjusted for clinical risk assessed as EuroSCORE II.

Results

During median follow-up of 3.8 years [IQR 2.7–4.9 years], 45 (6%) experienced CVD and 80 (11%) died. In survival analyses adjusted for EuroSCORE II, each 1% increase in amplitude of ESL was associated with CVD (HR 1.35 [95%CI 1.09–1.68], P = 0.006) and all-cause mortality (HR 1.29 [95%CI 1.08–1.54], P = 0.004). Similar findings applied to duration of ESL (per 10ms increase) and CVD (HR 1.12 [95%CI 1.02–1.23], P = 0.016) and all-cause mortality (HR 1.09 [95%CI 1.01––1.17], P = 0.031). The prognostic value of ESL amplitude was modified by sex (P interaction < 0.05), such that the prognostic value was greater in women for both endpoints. When adding ESL duration to EuroSCORE II, the net reclassification index improved significantly for both CVD and all-cause mortality.

Conclusions

Assessment of ESL provides independent and incremental prognostic information in addition to the EuroSCORE II for CVD and all-cause mortality in CABG patients.

Sex and gender in cardiovascular medicine: presentation and outcomes of acute coronary syndrome

Although health disparities in women presenting with acute coronary syndrome (ACS) have received growing attention in recent years, clinical outcomes from ACS are still worse for women than for men. Women continue to experience higher patient and system delays and receive less aggressive invasive treatment and pharmacotherapies. Gender- and sex-specific variables that contribute to ACS vulnerability remain largely unknown. Notwithstanding the sex differences in baseline coronary anatomy and function, women and men are treated the same based on guidelines that were established from experimental and clinical trial data over-representing the male population. Importantly, younger women have a particularly unfavourable prognosis and a plethora of unanswered questions remains in this younger population. The present review summarizes contemporary evidence for gender and sex differences in vascular biology, clinical presentation, and outcomes of ACS. We further discuss potential mechanisms and non-traditional risk conditions modulating the course of disease in women and men, such as unrecognized psychosocial factors, sex-specific vascular and neural stress responses, and the potential impact of epigenetic modifications.

Gender Bias in Cardiovascular Disease Prevention, Detection, and Management, with Specific Reference to Coronary Artery Disease

Even though cardiovascular disease (CVD) kills more women than men each year and remains a leading cause of death in women, it is a common misconception that women are less likely to develop CVD. Considerable sex difference exists between men and women with regard to prevention, investigations, and management of CVD. Coronary artery disease (CAD) is a major contributor to CVD morbidity and mortality and hence is specifically addressed in this article. With an explosive increase in the incidence of conventional risk factors for coronary artery disease in India, there has been an alarming increase in women's coronary events as much as men. A false sense of gender-based protection by estrogen leads to less aggressive and late prevention or management strategies that contribute to women's CAD. Metabolic syndrome (MetS) is an important contributor to future development of CAD and is also an indicator for earlier interventions for prevention. Due to physical inactivity and central obesity, MetS is more prevalent in women, especially postmenopausal. With estrogen loss, menopause marks a critical cardiovascular biological transition, with a significantly increased CVD risk in women aged >55 years. Certain female-specific risk factors, such as history of polycystic ovarian syndrome, pregnancy-induced hypertension, and gestational diabetes, also seem to play an essential role in the development of CVD in later life. Certain vascular and biological factors, such as smaller coronary vessel size, higher prevalence of small vessel disease, and lesser development of collateral flow, also play an important role. This review article is an attempt to provide important information on gender differences in CVD with specific emphasis on CAD.

Male-female differences in characteristics and early outcomes of patients undergoing tricuspid valve surgery: a national cohort study in the Netherlands

OBJECTIVES

This study aims to explore male-female differences in baseline and procedural characteristics, and outcomes of patients undergoing isolated or concomitant tricuspid valve (TV) surgery.

METHODS

All TV procedures registered between 2007 and 2016 in the database of the Netherlands Association for Cardio-Thoracic Surgery were analysed. Logistic regression analyses with interaction terms were used to determine whether sex was associated with hospital mortality.

RESULTS

Five thousand five hundred and eighty-two patients underwent TV surgery [isolated: N = 685 (49% male), TVrepair: N = 5286 (50% male) and TVreplacement: N = 250 (46% male)]. In the TVrepair group, females were significantly older, had less prior percutaneous/surgical coronary interventions, less extracardiac arteriopathies, a lower prevalence of renal impairment, less endocarditis, a lower prevalence of preoperative critical condition, less recent myocardial infarction, less concomitant coronary artery bypass grafting (CABG) and, in case of concomitant mitral valve surgery, less concomitant mitral valve repair compared to males. In the TVreplacement group, females more often had a history of prior valve surgery and less prior CABG. Hospital mortality for males and females was 7.0% (N = 183) and 6.1% (N = 163), P = 0.241 in the TVrepair group and 2.6% (N = 3) and 8.8% (N = 12), P = 0.074 in the TVreplacement group. Sex was not associated with hospital mortality (odds ratio (OR) 1.14, 95% confidence interval (CI) 0.88-1.48; P = 0.322). Sex demonstrated a significant interaction with the parameter 'critical preoperative condition' (OR 0.44, 95% CI 0.22-0.90; P = 0.026).

CONCLUSIONS

Substantial differences in patient and procedural characteristics existed between male and female patients undergoing TV surgery, although sex was not a derterminant for hospital mortality. Nevertheless, sex interacted with a critical preoperative condition, indicating the usefulness of separate risk factor models for males and females requiring TV surgery.

Comparison of Outcomes of Coronary Revascularization for Acute Myocardial Infarction in Men Versus Women

This study sought to examine the differences in the characteristics and outcomes between men and women who underwent percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) for acute myocardial infarction (AMI) in contemporary US practice. The Nationwide Inpatient Sample was used to identify patients who underwent revascularization for AMI between January 1, 2003 and December 31, 2016. The primary outcome was in-hospital mortality. Propensity score matching was utilized to account for differences in baseline characteristics. In total, 3,603,142 patients were included, of whom only 1,180,436 (33%) were women. Compared with men, women were older and had higher prevalence of key co-morbidities including diabetes, hypertension, congestive heart failure, and chronic kidney and lung disease (p <0.001). In the PCI cohort, women were significantly less likely to undergo multivessel PCI, to receive mechanical circulatory support, or to undergo atherectomy. In the CABG group, women were more likely to have concomitant valve surgery. In the propensity-matched cohorts, in-hospital mortality was higher for women than men regardless of revascularization strategy: 7.6% versus 6.6% for PCI in ST-elevation myocardial infarction, 2.0% versus 1.9% for PCI in non-ST-elevation myocardial infarction, and 5.7% versus 4.3% for CABG in any AMI (p <0.001). Women also had higher rates of major complications, longer hospitalizations, higher costs, and were less likely to be discharged home (vs nursing facility). These sex-based differences persisted over the study 14-year period. In conclusion, in a contemporary nationwide analysis of propensity score-matched patients, women who undergo revascularization for AMI have worse in-hospital outcomes than men regardless of revascularization mode.

Eicosanoid production varies by sex in mesenteric ischemia reperfusion injury

Intestinal ischemia/reperfusion (I/R)-induced injury is an inflammatory response with significant morbidity and mortality. The early inflammatory response includes neutrophil infiltration. However, the majority of rodent studies utilize male mice despite a sexual dimorphism in intestinal I/R-related diseases. We hypothesized that sex may alter inflammation by changing neutrophil infiltration and eicosanoid production. To test this hypothesis, male and female C57Bl/6 mice were subjected to sham treatment or 30 min intestinal ischemia followed by a time course of reperfusion. We demonstrate that compared to male mice, females sustain significantly less intestinal I/R-induced tissue damage and produced significant LTB₄ concentrations. Male mice release PGE₂. Finally, treatment with a COX-2 specific inhibitor, NS-398, attenuated I/R-induced injury, total peroxidase level, and PGE₂ production in males, but not in similarly treated female mice. Thus, I/R-induced eicosanoid production and neutrophil infiltration varies between sexes suggesting that distinct therapeutic intervention may be needed in clinical ischemic diseases.

Female Gender is not a Risk Factor for Early Mortality after Coronary Artery Bypass Grafting

Background:

The female gender is considered as a risk factor for morbidity and mortality after coronary artery bypass grafting (CABG).

Aim:

In this analysis, we assessed the impact of female gender on early outcome after CABG.

Study Design:

This is a retrospective analysis of data from our center situated in South India.

Statistical Analysis:

Patients were categorized according to gender and potential differences in pre-operative and post-operative factors were explored. Significant risk factors were then built in a multivariate model to account for differences in predicting gender influence on surgical outcome.

Methods:

773 consecutive patients underwent first time CABG between January 2015 and December 2016. 96.77% of cases were performed using off-pump technique. 132 (17.07%) patients were females. These patients formed the study group.

Results:

The in-house/ 30-day mortality in females was similar to that of males (3.03% vs. 3.12%, p value 0.957). Mediastinitis developed more commonly in females (5.35% vs. 1.30%; p value 0.004) compared to males. There were more re-admissions to hospital for female patients (21.37% in females vs. 10.14% in males, p value <0.001). In multivariate analysis using logistic regression; there was a significant association between age (OR 1.08), chronic obstructive airway disease (OR 4.315), and use of therapeutic antibiotics (OR 6.299), IABP usage (OR 11.18) and renal failure requiring dialysis (OR 28.939) with mortality.

Conclusions:

Early mortality in females was similar to that of males. Females were associated with higher rate of wound infection and readmission to hospital.

Sex-Specific Effects of the Nlrp3 Inflammasome on Atherogenesis in LDL Receptor-Deficient Mice

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In this study we observed sex-specific effects of the NLRP3 inflammasome on atherogenesis in LDLR-deficient mice, with NLRP3 inflammasome playing a more prominent role in atherosclerosis in female mice than in males.

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Sex hormones may be involved in NLRP3 inflammasome–mediated atherogenesis and may underlie differential responses to anti-NLRP3 therapy between males and females.

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Testosterone may play an inhibitory role by blocking NLRP3 inflammasome and inflammation in atherogenesis, whereas female sex hormones may promote NLRP3 inflammasome–mediated atherosclerosis.

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The results of the present study may help design future clinical trials, with the objective to personalize cardiovascular care for men and women.

In the Ldlr^-/- mouse model of atherosclerosis, female Nlrp3^-/- bone marrow chimera and Nlrp3^-/- mice developed significantly smaller lesions in the aortic sinus and decreased lipid content in aorta en face, but a similar protection was not observed in males. Ovariectomized female mice lost protection from atherosclerosis in the setting of NLRP3 deficiency, whereas atherosclerosis showed a greater dependency on NLRP3 in castrated males. Thus, castration increased the dependency of atherosclerosis on the NLRP3 inflammasome, suggesting that testosterone may block inflammation in atherogenesis. Conversely, ovariectomy reduced the dependency on NLRP3 inflammasome components for atherogenesis, suggesting that estrogen may promote inflammasome-mediated atherosclerosis.

Gender Differences in Postoperative Outcomes After Cardiac Surgery

Women presenting for cardiac surgery tend to be older and have hypertension, diabetes, and overweight or underweight body mass index than men. Despite improvements in surgical techniques and medications, women have increased risk for morbidity and mortality after multiple types of cardiac surgery. Women presenting for transcatheter aortic valve replacement are older and frailer than men, and have increased risk of intraoperative complications, but lower mortality at mid- and long-term ranges compared with men. Adherence to recovery and rehabilitation from cardiac surgery is challenging for women. Solutions should focus on increased family support, and use of group exercise and activities.

The Impact of Sex on Outcomes After Revascularization for Multivessel Coronary Disease

BACKGROUND

Coronary artery disease has historically been responsible for more deaths among women than men, and previous studies have suggested sex differences in revascularization approaches and outcomes. We sought to compare sex-specific adverse events in patients who underwent percutaneous or surgical revascularization for multivessel coronary artery disease.

METHODS

All patients at a single institution undergoing percutaneous coronary intervention or coronary artery bypass graft surgery for multivessel coronary artery disease between 2011 and 2018 were included. Propensity score matching was utilized to compare patients with similar baseline characteristics. Outcomes included death, major adverse cardiac and cerebrovascular events (MACCE), repeat revascularization, and readmissions.

RESULTS

Of the 6163 patients, 1679 (27.2%) were female. Male patients were more likely to have three-vessel disease (71.9% vs 68.6%, P = .002) and to undergo complete revascularization (69.9% vs 66.4%, P = .008). Female sex was associated with an increased hazard for death (hazard ratio 1.16, P = .03) and MACCE (hazard ratio 1.16, P = .02) but not repeat revascularization (hazard ratio 1.23, P = .16). In the matched cohorts, female sex was associated with lower survival at 1 year (90.63% vs 93.12%, P = .01) but not at 5 years (76.64% vs 77.33%, P = .20). Similarly, freedom from MACCE was lower for female patients at 1 year (87.79% vs 90.19%, P = .03) but was comparable at 5 years (73.22% vs 74.3%, P = .10).

CONCLUSIONS

In a matched analysis pooling percutaneous and surgical revascularization, female sex was associated with worse outcomes at 1 year although there were no sex differences at 5 years of follow-up. Increasing coronary artery bypass graft surgery utilization and the completeness of revascularization in female patients may be targets for improving 1-year survival and freedom from MACCE.

Sex differences in vascular reactivity of coronary artery bypass graft conduits

Females have increase in-hospital mortality and poorer outcomes following coronary artery bypass grafting (CABG). Biological differences in the reactivity of the graft conduits to circulating catecholamine may contribute to this sex difference. This study examined sex differences in the vasoconstrictor responses of internal mammary artery (IMA) and saphenous vein (SV) conduits to phenylephrine (PE) and endothelin-1 (ET-1). Functional IMA and SV were obtained from 78 male and 50 female patients undergoing CABG (67.7 ± 11 and 69 ± 10 years, respectively) and subjected to the following experimental conditions. (1) Concentration response curves for PE and ET-1 were generated in an intact IMA and SV and endothelium denuded IMA segments, (2) in the presence of the nitric oxide synthase inhibitor (L-NAME) or the cyclooxygenase inhibitor (indomethacin) in an endothelium-intact IMA and (3) the activity state (abundance and phosphorylation) of the α1-adrenergic receptor was investigated using Phos-tag™ western blot analysis. (1) Compared to male, female IMA and SV were hypersensitive to PE but not ET-1 (p < 0.05). The female IMA hypersensitivity response to PE was abolished following endothelial denudation, (2) persisted in the presence of L-NAME but was abolished in the presence of indomethacin and (3) there was no sex differences in the abundance and phosphorylation of the α1-adrenergic receptor in IMA. Female IMA and SV graft conduits are hypersensitive to α1-adrenergic stimuli. This endothelial cyclooxygenase pathway-mediated hypersensitivity may produce excessive IMA and SV graft constriction in females administered catecholamines and could contribute to their poorer CABG outcomes.

Sex differences in gene expression in response to ischemia in the human left ventricular myocardium

Sex differences exist in the prevalence, presentation and outcomes of ischemic heart disease (IHD). Females have higher risk of heart failure post-myocardial infarction relative to males and are two to three times more likely to die after coronary artery bypass grafting surgery. We examined sex differences in human myocardial gene expression in response to ischemia. Left ventricular biopsies from 68 male/46 female patients undergoing aortic valve replacement surgery were obtained at baseline and after a median 74 min of cold cardioplegic arrest/ischemia. Transcriptomes were quantified by RNA-sequencing. Cell-type enrichment analysis was used to estimate the identity and relative proportions of different cell types in each sample. A sex-specific response to ischemia was observed for 271 genes. Notably, the expression FAM5C, PLA2G4E and CYP1A1 showed an increased expression in females compared to males due to ischemia and DIO3, MT1G and CMA1 showed a decreased expression in females compared to males due to ischemia. Functional annotation analysis revealed sex-specific modulation of the oxytocin signaling pathway and common pathway of fibrin clot formation. Expression quantitative trait locus (eQTL) analysis identified variant-by-sex interaction eQTLs, indicative of sex differences in the genotypic effects on gene expression. Cell-type enrichment analysis showed sex-bias in proportion of specific cell types. Common lymphoid progenitor cells and M2 macrophages were found to increase in female samples from pre- to post-ischemia, but no change was observed in male samples. These differences in response to myocardial ischemia provide insight into the sexual dimorphism of IHD and may aid in the development of sex-specific therapies that reduce myocardial injury.