Coronary Artery Bypass Grafting in Women 50 Years or Younger

Determinants of 30-day mortality in elderly patients admitted to a cardiovascular surgery intensive care unit

BACKGROUND

This study aims to identify the factors influencing 30-day morbidity and mortality in patients aged 65 and older undergoing cardiovascular surgery.

METHODS

Data from 360 patients who underwent cardiac surgery between January 2012 and August 2021 in the Cardiovascular Surgery Intensive Care Unit (CVS ICU) were analyzed. Patients were categorized into two groups: "mortality+" (33 patients) and "mortality-" (327 patients). Factors influencing mortality, including preoperative, intraoperative, and postoperative risk factors, complications, and outcomes, were assessed.

RESULTS

Significant differences were observed between the two groups in factors affecting mortality, including extubation time, ICU stay duration, blood transfusion, surgical reexploration, aortic clamp duration, glomerular filtration rate (GFR), blood urea nitrogen (BUN), creatinine, hemoglobin A1c (HbA1c) levels, and the lowest systolic blood pressure during the first 24 hours in the ICU (p<0.05). The "mortality+" group had longer extubation times and ICU stays, required more blood transfusions, and had higher BUN-creatinine ratios, but lower systolic blood pressures, GFR, and HbA1c levels. Mortality was also higher in patients needing noradrenaline infusions and those who underwent reoperation for bleeding (p<0.05).

CONCLUSION

By optimizing preoperative renal function, minimizing extubation time, shortening ICU stays, and carefully managing blood transfusions, surgical reexplorations, aortic clamp duration, and HbA1c levels, we believe that the mortality rate can be reduced in elderly patients. Key strategies include shortening aortic clamp times, reducing perioperative blood transfusions, and ensuring effective bleeding control.

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.

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.

Unravelling the Difference Between Men and Women in Post-CABG Survival

Objectives

Women have a worse prognosis after coronary artery bypass grafting (CABG) surgery compared to men. We sought to quantify to what extent this difference in post-CABG survival could be attributed to sex itself, or whether this was mediated by difference between men and women at the time of intervention. Additionally, we explored to what extent these effects were homogenous across patient subgroups.

Methods

Time to all-cause mortality was available for 102,263 CABG patients, including 20,988 (21%) women, sourced through an individual participant data meta-analysis of five cohort studies. Difference between men and women in survival duration was assessed using Kaplan-Meier estimates, and Cox's proportional hazards model.

Results

During a median follow-up of 5 years, 13,598 (13%) patients died, with women more likely to die than men: female HR 1.20 (95%CI 1.16; 1.25). We found that differences in patient characteristics at the time of CABG procedure mediated this sex effect, and accounting for these resulted in a neutral female HR 0.98 (95%CI 0.94; 1.02). Next we performed a priori defined subgroup analyses of the five most prominent mediators: age, creatinine, peripheral vascular disease, type 2 diabetes, and heart failure. We found that women without peripheral vascular disease (PVD) or women aged 70+, survived longer than men (interaction p-values 0.04 and 6 × 10-5, respectively), with an effect reversal in younger women.

Conclusion

Sex differences in post-CABG survival were readily explained by difference in patient characteristics and comorbidities. Pre-planned analyses revealed patient subgroups (aged 70+, or without PVD) of women that survived longer than men, and a subgroup of younger women with comparatively poorer survival.

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.

Sex difference in the risk factor distributions and outcomes after coronary artery bypass graft surgery in the young population

OBJECTIVES

Coronary artery disease is becoming a major health concern in the young population. Male and female patients may experience different journeys after coronary artery disease events. We aimed to evaluate risk factors and compare outcomes between young male and female patients undergoing coronary artery bypass graft surgery (CABG).

METHODS

In this registry-based large sample size study, patients undergoing isolated CABG at a young age (premature isolated CABG) between 2007 and 2016 were included and followed up until 2020. Premature was defined as women and men younger than 55 years old. The main end points of the study were 7-year all-cause mortality and 7-year major adverse cardiovascular and cerebrovascular events (MACCEs).

RESULTS

Of a total of 24 428 patients who underwent CABG, 7217 patients (men-to-women ratio ≈4:1) with premature isolated CABG were included. The median follow-up duration was 78.5 months (75.2-81.6 months). The prevalence rates of diabetes mellitus, hypertension, dyslipidaemia and obesity were significantly higher in women than in men (58.3% vs 28.6%, 64.2% vs 38.5%, 69.7% vs 55.3% and 44.7 vs 23.9, respectively; all Ps < 0.05). The risk factor burden (mean of the risk factor count per year) was also higher among the female population. Diabetes mellitus was the common mortality predictor between men and women. In the subgroup analysis (interaction analysis in the adjusted model), hypertensive females had a higher rate of MACCE and a higher rate of mortality than hypertensive males; however, this difference was not significant in the non-hypertensive population. Opium addiction was a strong predictor of MACCE and all-cause mortality among men. Female patients had a higher rate of 7-year MACCE (hazard ratio, 1.33; 95% confidence interval, 1.16-1.51) and a higher rate of 7-year all-cause mortality (hazard ratio, 1.23; 95% confidence interval, 0.98-1.53).

CONCLUSIONS

The risk factor profile and predictors of outcomes were different between our female and male patients. Women carried a higher risk of events and mortality after CABG at a young age.

Impact of gender on 10-year outcome after coronary artery bypass grafting

 

OBJECTIVES

Our goal was to evaluate the impact of gender on the 10-year outcome of patients after isolated coronary artery bypass grafting (CABG) included in the Italian nationwide PRedictIng long-term Outcomes afteR Isolated coronary arTery bypass surgery (PRIORITY) study.

METHODS

The PRIORITY project was designed to evaluate the long-term outcomes of patients who underwent CABG and were included in 2 prospective multicentre cohort studies. The primary end point of this analysis was major adverse cardiac and cerebrovascular events. Baseline differences between the study groups were balanced with propensity score matching and inverse probability of treatment. Time to events was analysed using Cox regression and competing risk analysis.

RESULTS

The study population comprised 10 989 patients who underwent isolated CABG (women 19.6%). Propensity score matching produced 1898 well-balanced pairs. The hazard of major adverse cardiac and cerebrovascular event was higher in women compared to men [adjusted hazard ratio (HR) 1.13, 95% confidence interval (CI) 1.03-1.23; P = 0.009]. The incidence of major adverse cardiac and cerebrovascular event in women was significantly higher at 1 year (HR 1.31, 95% CI 1.11-1.55; P < 0.001) and after 1 year (HR 1.11, 95% CI 1.00-1.24; P = 0.05). Mortality at 10 years in the matched groups was comparable (HR 1.04, 95% CI 0.93-1.16; P = 0.531). Women have significantly a higher 10-year risk of myocardial infarction (adjusted HR 1.40, 95% CI 1.17-1.68; P = 0.002) and percutaneous coronary intervention (adjusted HR 1.32, 95% CI 1.10-1.59; P = 0.003).

CONCLUSIONS

The present study documented an excess of non-fatal cardiac events after CABG among women despite comparable 10-year survival with men. These findings suggest that studies investigating measures of tertiary prevention are needed to decrease the risk of adverse cardiovascular events among women.

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.

Relative survival after aortic valve surgery in patients with bicuspid aortic valves

OBJECTIVES

The objective of this cohort study was to analyse long-term relative survival in patients with bicuspid aortic valve (BAV) who underwent aortic valve surgery.

METHODS

We studied 865 patients with BAVs who participated in three prospective cohort studies of elective, open-heart, aortic valve surgery at the Karolinska University Hospital, Stockholm, Sweden, between 2007 and 2020. The expected survival for the age, sex and calendar year-matched general Swedish population was obtained from the Human Mortality Database. The Ederer II method was used to calculate relative survival, which was used as an estimate of cause-specific survival.

RESULTS

No differences were found in the observed versus expected survival at 1, 5, 10 or 12 years: 99%, 94%, 83% and 76% vs 99%, 93%, 84% and 80%, respectively. The relative survival at 1, 5, 10 and 12 years was 100% (95% CI 99% to 100%), 101% (95% CI 99% to 103%), 99% (95% CI 95% to 103%) and 95% (95% CI 87% to 102%), respectively. The relative survival at the end of follow-up tended to be lower for women than men (86% vs 95%). The mean follow-up was 6.3 years (maximum 13.3 years).

CONCLUSIONS

The survival of patients with BAV following aortic valve surgery was excellent and similar to that of the general population. Our results suggest that the timing of surgery according to current guidelines is correct and provide robust long-term survival rates, as well as important information about the natural history of BAV in patients following aortic valve surgery.

Coronary Artery Bypass Grafting in Women 50 Years or Younger

Background

Prior research has shown higher mortality in women with severe coronary artery disease compared with men, particularly in younger patients. It is unknown if this could be attributable to an adverse risk factor profile.

Methods and Results

In a population‐based cohort study, we included all adults ≤50 years of age (932 women and 4514 men) who underwent coronary artery bypass grafting from 1995 to 2013 from the SWEDEHEART (Swedish Web System for Enhancement and Development of Evidence‐Based Care in Heart Disease Evaluated According to Recommended Therapies) register. Following inverse probability of treatment weighting, we investigated differences between women and men. Women had a higher prevalence of cardiovascular risk factors compared with men. There was no difference in early mortality between women and men (unadjusted: 1.3% versus 0.9%; hazard ratio, 1.42; 95% CI, 0.75–2.70; weighted sample: 1.1% versus 1.0%; hazard ratio, 1.10; 95% CI, 0.52–2.30). During a median follow‐up time of 11.8 years, in the unweighted population, the risk of death was greater in women compared with men (hazard ratio, 1.34; 95% CI, 1.13–1.58). However, in the weighted sample, the risk of death was not significantly different in women compared with men (hazard ratio, 1.02; 95% CI, 0.83–1.26).

Conclusions

Women ≤50 years of age had a higher unadjusted risk of death after coronary artery bypass grafting compared with men, but this was explained by a clustering of cardiovascular risk factors. Female sex per se was not associated with increased mortality or major adverse cardiovascular events. Early mortality was not increased in women compared with men, even though younger women in our study had an increased burden of risk factors known to affect early risk.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02276950.