Prevalence of risk factors, and not gender per se, determines short- and long-term survival after coronary artery bypass surgery

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.

The Influence of Choice of Surgical Procedure on Long-Term Survival After Cardiac Surgery

BACKGROUND

There is some interest in long-term survival after various cardiac surgical strategies, including off-pump versus on-pump coronary artery surgery (CAG), mitral valve (MV) repair versus replacement, and aortic valve (AV) bioprosthetic versus mechanical replacement.

METHODS

We studied patients older than 49 years of age, recording risk factors and surgical details at the time of surgery. We classified procedures as: MV surgery with or without concurrent grafts or valves; AV surgery with or without concurrent CAG; or isolated CAG. Follow-up was through the state death register and state-wide hospital attendance records. Risk-adjusted survival was estimated using Cox proportional hazards. Observed survival was compared to the expected age- and sex- matched population survival.

RESULTS

During a median follow-up of 14.8 years 5,807 of 11,718 patients died. The difference between observed and expected survival varied between 3.4 years for AV surgery and 9.6 years for females undergoing MV surgery. The risk-adjusted mortality hazard rate after off-pump CAG was 0.93 (95% CI 0.8-1.0, p=0.84), MV repair 0.67 (95% CI 0.6-0.8, p<0.0001), MV bioprosthesis 0.82 (95% CI 0.81 (0.6-1.0, p=0.11) and bioprosthetic AV replacement 1.02 (95% CI 0.9-1.2, p=0.82).

CONCLUSIONS

Compared to the general population, cardiac surgical patients have a shorter than expected life expectancy. We observed a survival benefit of mitral valve repair over replacement. We did not observe significant survival differences between off-pump and on-pump CAG, nor between bioprosthetic and mechanical replacement.

Relative impact of red blood cell transfusion and anaemia on 5-year mortality in cardiac surgery

OBJECTIVES

The aim was to compare the relative effects of red blood cell (RBC) transfusion and preoperative anaemia on 5-year mortality following open-heart cardiac surgery using structural equation modelling. We hypothesized that patient risk factors associated with RBC transfusion are of larger importance than transfusion itself.

METHODS

This prospective cohort study, part of the Cardiac Surgery Outcome Study at St. Olavs University Hospital, Trondheim, Norway, included open-heart on-pump cardiac surgery patients operated on from 2000 through 2017 (n = 9315). Structural equation modelling, which allows for intervariable correlations, was used to analyse pathway diagrams between known risk factors and observed mortality between 30 days and 5 years postoperatively. Observation times between 30 days and 1 year, and 1-5 years postoperatively were also compared with the main analysis.

RESULTS

In a simplified model, preoperative anaemia had a larger effect on 5-year mortality than RBC transfusion (standardized coefficients: 0.17 vs 0.09). The complete model including multiple risk factors showed that patient risk factors such as age (0.15), anaemia (0.10), pulmonary disease (0.11) and higher creatinine level (0.12) had larger effects than transfusion (0.03). Results from several sensitivity analyses supported the main findings. The models showed good fit.

CONCLUSIONS

Preoperative anaemia had a larger impact on 5-year mortality than RBC transfusion. Differences in 5-year mortality were mainly associated with patient risk factors.

Retinal changes in patients with angina pectoris and anginal equivalents: a study of patients with normal coronary angiography

Background and aims. Approximately 10-30% of the patients with typical symptoms of angina pectoris have normal angiography showing normal macrovasculature. In these patients, however, the microvascular problems should be monitored. Hence, the main aim of this study is to evaluate retinal changes in normal angiographic patients.Methods. In this descriptive cross-sectional study, 60 normal angiographic patients with typical chest pain or anginal equivalents visiting Modarres Hospital Cardiology Research Center between 2018 and 2019 were enrolled and retinal changes were determined in Labbafinejad Hospital by Optical Coherence Tomography Angiography using Foveal Avascular Zone (FAZ), Superficial Vascular Density (SVD), and Deep Vascular Density (DVD).Results. The results of this study demonstrated that FAZ was normal in all subjects, but SVD and DVD were abnormal in 45% and 8.3%, respectively. Totally, 18.5% and 66.7% showed abnormal SVD among stable angina (SA) and unstable angina (UA) cases, respectively (P < 0.001). There was no statistically significant difference between abnormal DVD in SA and UA cases (P = 0.058). Abnormal SVD was significantly more common among diabetic patients (P < 0.001), while DVD was not related to diabetes presence in the study population (P > 0.05). Moreover, abnormal SVD was more common among patients with chest pain (P = 0.036), while there was no significant difference for DVD (P = 0.371). Interestingly, abnormal ECG was associated with both abnormal DVD and SVD.Conclusions. The results of this study showed that nearly half of the patients with angina pectoris or anginal equivalents who revealed normal angiographic findings may suffer from retinal changes. Thus, retinal assessment is needed in these patients to evaluate microvascular changes.

Web-Based Calculator Predicts Surgical-Site Infection After Thoracolumbar Spine Surgery

BACKGROUND

Surgical-site infection (SSI) after spine surgery leads to increased length of stay, reoperation, and worse patient quality of life. We sought to develop a web-based calculator that computes an individual's risk of a wound infection following thoracolumbar spine surgery.

METHODS

We performed a retrospective review of consecutive patients undergoing elective degenerative thoracolumbar spine surgery at a tertiary-care institution between January 2016 and December 2018. Patients who developed SSI requiring reoperation were identified. Regression analysis was performed and model performance was assessed using receiver operating curve analysis to derive an area under the curve. Bootstrapping was performed to check for overfitting, and a Hosmer-Lemeshow test was employed to evaluate goodness-of-fit and model calibration.

RESULTS

In total, 1259 patients were identified; 73% were index operations. The overall infection rate was 2.7%, and significant predictors of SSI included female sex (odds ratio [OR] 3.0), greater body mass index (OR 1.1), active smoking (OR 2.8), worse American Society of Anesthesiologists physical status (OR 2.1), and greater surgical invasiveness (OR 1.1). The prediction model had an optimism-corrected area under the curve of 0.81. A web-based calculator was created: https://jhuspine2.shinyapps.io/Wound_Infection_Calculator/.

CONCLUSIONS

In this pilot study, we developed a model and simple web-based calculator to predict a patient's individualized risk of SSI after thoracolumbar spine surgery. This tool has a predictive accuracy of 83%. Through further multi-institutional validation studies, this tool has the potential to alert both patients and providers of an individual's SSI risk to improve informed consent, mitigate risk factors, and ultimately drive down rates of SSIs.

Predicting Length of Stay of Coronary Artery Bypass Grafting Patients Using Machine Learning

BACKGROUND

There is a growing need to identify which bits of information are most valuable for healthcare providers. The aim of this study was to search for the highest impact variables in predicting postsurgery length of stay (LOS) for patients who undergo coronary artery bypass grafting (CABG).

MATERIALS AND METHODS

Using a single institution's Society of Thoracic Surgeons (STS) Registry data, 2121 patients with elective or urgent, isolated CABG were analyzed across 116 variables. Two machine learning techniques of random forest and artificial neural networks (ANNs) were used to search for the highest impact variables in predicting LOS, and results were compared against multiple linear regression. Out-of-sample validation of the models was performed on 105 patients.

RESULTS

Of the 10 highest impact variables identified in predicting LOS, four of the most impactful variables were duration intubated, last preoperative creatinine, age, and number of intraoperative packed red blood cell transfusions. The best performing model was an ANN using the ten highest impact variables (testing sample mean absolute error (MAE) = 1.685 d, R² = 0.232), which performed consistently in the out-of-sample validation (MAE = 1.612 d, R² = 0.150).

CONCLUSION

Using machine learning, this study identified several novel predictors of postsurgery LOS and reinforced certain known risk factors. Out of the entire STS database, only a few variables carry most of the predictive value for LOS in this population. With this knowledge, a simpler linear regression model has been shared and could be used elsewhere after further validation.

Sex-Based Outcomes After Coronary Artery Bypass Grafting

BACKGROUND

Sex is suggested to influence outcomes after coronary artery bypass grafting (CABG), although evidence on long-term mortality is controversial and cardiovascular outcome data are lacking. We studied sex differences in outcomes after isolated CABG.

METHODS

Consecutive patients with first-time isolated CABG for stable coronary artery disease between 2004 and 2014 in Finland were retrospectively recognized from national registry (n = 14,681; 21% women). Propensity scoring and inverse probability weighting were used to adjust for baseline features. Median follow-up was 10.0 (maximum 14.6) years.

RESULTS

Cumulative major adverse cardiovascular event (myocardial infarction, stroke, or cardiovascular death) rate was 44.5% in men and 49.9% in women during follow-up (hazard ratio [HR], 0.98; P = .633). All-cause mortality was 48.5% in men vs 46.0% in women (HR, 1.20; 95% confidence interval, 1.11-1.30; P < .0001), and cardiovascular mortality was 29.5% vs 31.3% (P = .625). Stroke rate was comparable between men and women (19.4% vs 23.6%; P = .625). Myocardial infarction occurred more frequently in women (20.0% vs 23.6%; HR, 0.84; 95% confidence interval, 0.75-0.95; P = .005). Redo revascularization was performed to 12.8% of women and to 12.6% of men (P = .100). Anticoagulation was more frequently used by men and adenosine diphosphate inhibitors and diuretics were more frequently used by women after CABG. Usage of statins, angiotensin-converting-enzyme inhibitors or angiotensin-blockers, beta-blockers, calcium-channel blockers, or nitrates did not differ between sexes after CABG.

CONCLUSIONS

Sex was not an independent predictor of long-term major adverse cardiovascular events after CABG in this population-based cohort study. However, men had higher long-term all-cause mortality and women higher risk of myocardial infarction. Long-term outcomes should be accounted for when considering sex as a risk factor for CABG.

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.

Diastolic dysfunction - What an anesthesiologist needs to know?

Diastolic dysfunction (DD) is a common condition that is increasingly encountered in patients undergoing both cardiac and noncardiac surgery as the age profile of our patient population increases and the noninvasive diagnosis of DD becomes more accessible. There is a growing body of evidence demonstrating the significance of DD and adverse perioperative outcomes, and thus, it is becoming imperative for anesthesiologists to have an understanding of the pathophysiology, diagnosis, and management of patients with DD. Current guidelines are based on transthoracic echocardiogram (TTE) measurements in patients who are spontaneously breathing and in a euvolemic state and, consequently, not applicable to the perioperative period. In this review article, we discuss the grading of DD as well as introduce a practical approach to the diagnosis and management of patients with DD during the perioperative period.

Gender-related risk factors for surgical site infections. Results from 10 years of surveillance in Germany

Background

Surgical site infections (SSI) are among the most frequently occurring healthcare-associated infections worldwide. Various analyses to determine risk factors have been conducted in the past, generally attributing a higher SSI-risk to male patients. However, when focusing on specific procedures, this is not always true. Our objective was to identify for which procedures male or female sex represents an independent risk factor for SSI and which parameters may explain these differences.

Methods

We used the database of surgical procedures from the German national nosocomial infection surveillance system. We included procedures conducted between 2008 and 2017. We excluded procedures solely executed for one sex (e.g. mastectomy) and procedures with 20,000 or fewer operations. The observed outcome was the occurrence of SSI. All models were adjusted for confounders, which were eliminated with backward selection. The following factors were included in the analysis: age, ASA score, wound contamination class, duration of surgery, and season. All models contained the investigated factor sex.

Results

Sixteen procedure types with 1,266,782 individual procedures and 18,824 SSI were included. Overall, the incidence rate ratio and the adjusted odds ratio for SSI were significantly higher for male patients. The included individual procedures were grouped into five surgical categories. For orthopedics and traumatology as well as abdominal surgery, SSI-rates were significantly higher for male patients. For heart and vascular surgery, SSI-rates were significantly higher for female patients. Other included surgical categories and individual procedures yielded diverse results. Similar results were found when solely analyzing deep and organ-space SSI. Multivariable analysis for attributable gender-related risk factors revealed differences with regard to underlying risk factors.

Conclusions

SSI-rates differ by sex for certain procedures. When examining underlying risk factors, differences between male and female patients can be demonstrated. Our analysis considered a limited number of parameters, which were not sufficient to fully explain the observed differences. Further studies are required to obtain a more comprehensive understanding of the topic and to include gender-specific aspects into future SSI-prevention strategies.

Is female sex an independent risk factor for early mortality in isolated coronary artery bypass graft? A propensity-matched analysis

AIMS

Despite several studies reporting a higher mortality rate for women undergoing isolated coronary artery bypass graft (CABG) surgery, this issue has not been completely clarified. The aim of the current study was to determine if sex differences in CABG surgery affect adjusted operative results and operative mortality.

METHODS

Between January 2005 and December 2012, 3756 consecutive patients (3009 men and 747 women) underwent isolated CABG at our institution. Women presented with older age, smaller BSA and higher rate of preoperative comorbidities. The propensity score methodology was used to obtain risk-adjusted outcome comparisons between the two groups.

RESULTS

The distribution of preoperative variables among matched pairs (553 patients in both groups) was, on average, equal. Propensity-matched women received a similar number of distal anastomoses (P = 0.56), had similar rate of left internal thoracic artery (LITA) graft (P = 0.73) and comparable extracorporeal circulation (P = 0.61) and aortic cross-clamp (P = 0.39) time as men. Postoperative complications were comparable in the two study groups with the exception of postoperative transfusion rate which was significantly higher in women (P = 0.01). However, operative mortality (3.8 vs. 2.7%; P = 0.20), perioperative acute myocardial infarction (P = 0.50) and stroke (P = 0.75) were not significantly different between the two groups. Interestingly, after adjustment for the other baseline characteristics, female patients with diabetes (P = 0.03), preoperative renal dysfunction (P = 0.07) and obesity (P = 0.07) exhibited a greater operative mortality rate compared with men with the same comorbidities.

CONCLUSION

After adjustment for preoperative variables, female sex seems not to be an independent risk factor for early mortality in isolated CABG surgery. However, renal impairment, diabetes and obesity seem to play an important role in the operative risk profile of women undergoing isolated CABG.

Association Between Adverse Clinical Outcomes After Coronary Artery Bypass Grafting and Perioperative Blood Transfusions

Background

Bleeding is a serious complication of coronary artery bypass grafting that often leads to blood transfusion. Approximately 50% of patients who have the surgery receive blood products, and blood transfusions play a role in adverse outcomes after the surgery.

Objective

To examine the association between perioperative blood transfusion and postoperative adverse outcomes in patients undergoing coronary artery bypass grafting.

Methods

A systematic review of the literature, via the matrix method of quality evaluation, was conducted. PubMed, CINAHL, and Science Direct databases for 2000 through 2016 were searched. Inclusion criteria were articles published in English and original research related to clinical outcomes of blood transfusion after coronary artery bypass grafting. Seventeen articles were included in the review.

Results

Mortality, both short- and long-term, was significantly higher in transfusion patients than in nontransfusion patients. Patients with transfusion of red blood cells had higher resource utilization and more complications, including infection, pneumonia, renal failure, graft occlusion, and atrial fibrillation, than did nontransfusion patients.

Conclusion

An association exists between red blood cell transfusions and adverse clinical outcomes for patients undergoing coronary artery bypass grafting. Transfusion of red blood cells is sometimes unnecessary, may be injurious, and should be used cautiously. Even a single-unit increase in perioperative red blood cell transfusions can have a significant adverse impact on outcomes. Individual benefits and risks should be weighed before transfusion to avoid adverse outcomes. Transfusion guidelines should be reviewed to include the latest evidence to guarantee the most appropriate use of blood products.

Gender and intraoperative blood transfusion: analysis of 54,122 non-reoperative coronary revascularization procedures

Background:

Previous studies have shown that women undergoing isolated coronary artery bypass graft (CABG) surgery have an increased risk for postoperative morbidity and mortality when compared to men. Additionally, recent evidence suggests that blood transfusions are independently associated with an increased risk of adverse outcome.

Methods:

We evaluated gender differences in the risk of intraoperative red blood cell (RBC) transfusion during CABG surgery. Consecutive, non-reoperative CABG procedures performed across 196 institutions between April 2012 and May 2015 were retrospectively reviewed. Gender differences for intraoperative transfusion were evaluated with a multi-variable binary logistic regression model, adjusting for age, blood volume (Nadler formula to normalize for height and weight), body mass index, procedure acuity, net extracorporeal circuit prime volume, use of autologous priming, first hematocrit (Hct) in the operating room (OR), nadir Hct on cardiopulmonary bypass (CPB), volume added on CPB, ultrafiltration volume, urine output on CPB and procedure duration.

Results:

Among 54,122 patients (25.3% female), 21.6% (n = 11,701) received a RBC transfusion. Compared to men, female patients were older (66 years vs. 64 years, p<0.001), had lower blood volumes (4.3L vs. 5.6L, p<0.001) and a lower preoperative Hct (32.9% vs. 37.2%, p<0.001). Transfusion rates were three-fold higher in women versus men (45.1% vs. 13.7%, p<0.001). After adjustment for independent predictors of intraoperative transfusion, women remained at increased risk versus men (OR = 1.30, 95%CI = 1.19−1.43).

Conclusions:

Women have an increased risk of intraoperative RBC transfusion versus men. After adjusting for height and weight, much of this risk is due to gender differences in preoperative Hct and blood volume; however, a residual significant risk remained after adjustment. Perfusion strategies aimed at gender differences may minimize unnecessary transfusions. Future study on the impact of gender on transfusion practice in cardiac surgery is warranted.

Effect of Gender on Postoperative Morbidity and Mortality Outcomes: A Retrospective Cohort Study

Full extent of gender differences on postoperative outcomes has never been studied on large scale, specifically postoperative complications. This study aims to assess the effect of gender on 30-day morbidity and mortality after major surgery. A retrospective cohort study was carried out using data of patients undergoing major surgeries from the American College of Surgeons’ National Surgical Quality Improvement Program database between 2008 and 2011. Demographics, pre- and perioperative risk factors, as well as 30-day morbidities, both overall and specific, were reviewed. The 30-day mortality data were also assessed. Multivariate logistic regression analyses, basic (Adj1) and extended (Adj2), were used to assess the association between gender and outcomes. Out of 1,409,131 patients, 57.2 per cent were females. Females had lower prevalence of most system-specific risk variables. Overall morbidities were also lower in females versus males, even after adjustment for variables [total overall morbidity: ORadj2 = 0.9 (0.89–0.92), P < 0.0001] except in some cases such as after cardiac surgeries [ORadj2 = 1.29 (1.14–1.44), P < 0.0001] and vascular surgeries [ORadj2 = 1.14 (1.10–1.18), P < 0.0001], where overall morbidities of females were higher. Specific morbidities were also lower in females than in males in all types of complications except central nervous system-related postoperative complications [ORadj2 = 1.15 (1.08–1.22), P < 0.0001] and return to the operating room [ORadj2 = 1.06 (1.04–1.08), P < 0.0001]. The 30-day mortality rate for females was lower than males [ORadj2 = 0.99 (0.96–1.03), P = 0.94]. Female gender was associated with less perioperative morbidity and mortality versus males, but they did worse after cardiovascular procedures and had more central nervous system-related complications. These outcomes should be taken into consideration by surgeons and should be evaluated further in future studies.

Female sex is not a risk factor for post procedural mortality in coronary bypass surgery in the elderly: A secondary analysis of the GOPCABE trial

OBJECTIVE

Female sex is considered a significant risk in cardiac surgery and is included in the majority of scores for risk assessment. However, the evidence is controversial and older women undergoing cardiac surgery have not specifically been investigated. We assessed the influence of female sex on surgical risk (30-day mortality) in a secondary analysis of the GOPCABE trial (German Off-Pump Coronary Artery Bypass grafting in the Elderly (GOPCABE) trial, comparing on- to off-pump) and also evaluated its impact on risk prediction from commonly used risk scores.

METHODS

We performed logistic regression analyses on the GOPCABE trial population, where patients were randomized to either on- or off-pump CABG. The study was performed in 12 cardiac surgery centers in Germany and analyzed 2394 patients having undergone CABG at age ≥75 years (1187 on-pump, 1207 off-pump). Of the 2394 patients, 755 (32%) were women. The logistic EuroSCORE and the German KCH score were calculated as expected (E) mortality and values were compared to observed (O) 30-day mortality (O/E ratio).

RESULTS

There was no difference in mortality or major cardiovascular adverse events after 30 days between men and women for both on- and off-pump CABG (men: on- vs. off-pump OR = 0.90, 95%-CI: [0.63;1.27]; women: on- vs. off-pump OR = 1.07, 95%-CI: [0.62;1.87]). Therefore, groups were combined for further analyses. Both men and women had considerable and similar comorbidities. Expected mortality was significantly higher for women than for men (logistic EuroSCORE: 8.88±6.71% vs. 7.99±6.69%, p = 0.003; KCH score: 4.42±3.97% vs. 3.57±3.65%, p = 0.001). However, observed mortality rates (O) tended to be even lower in women (2.1% vs. 3.0%). The O/E ratio was closer to 1 in men than in women (0.84 vs. 0.47). Excluding female sex from the risk models increased O/E ratio to 0.69.

CONCLUSIONS

Female sex is not a risk factor in coronary bypass surgery in the GOPCABE population. The result is the same for on- and off-pump surgery. Since female sex is a component of most risk scores, the findings may identify a potential inaccuracy in current surgical risk assessment, specifically for elderly women.

TRIAL REGISTRATION

Clinicaltrials.gov GOPCABE trial No. NCT00719667.

Gender disparities in red blood cell transfusion in elective surgery: a post hoc multicentre cohort study

OBJECTIVES

A post hoc gender comparison of transfusion-related modifiable risk factors among patients undergoing elective surgery.

SETTINGS

23 Austrian centres randomly selected and stratified by region and level of care.

PARTICIPANTS

We consecutively enrolled in total 6530 patients (3465 women and 3065 men); 1491 underwent coronary artery bypass graft (CABG) surgery, 2570 primary unilateral total hip replacement (THR) and 2469 primary unilateral total knee replacement (TKR).

MAIN OUTCOME MEASURES

Primary outcome measures were the number of allogeneic and autologous red blood cell (RBC) units transfused (postoperative day 5 included) and differences in intraoperative and postoperative transfusion rate between men and women. Secondary outcomes included perioperative blood loss in transfused and non-transfused patients, volume of RBCs transfused, perioperative haemoglobin values and circulating red blood volume on postoperative day 5.

RESULTS

In all surgical groups, the transfusion rate was significantly higher in women than in men (CABG 81 vs 49%, THR 46 vs 24% and TKR 37 vs 23%). In transfused patients, the absolute blood loss was higher among men in all surgical categories while the relative blood loss was higher among women in the CABG group (52.8 vs 47.8%) but comparable in orthopaedic surgery. The relative RBC volume transfused was significantly higher among women in all categories (CABG 40.0 vs 22.3; TKR 25.2 vs 20.2; THR 26.4 vs 20.8%). On postoperative day 5, the relative haemoglobin values and the relative circulating RBC volume were higher in women in all surgical categories.

CONCLUSIONS

The higher transfusion rate and volume in women when compared with men in elective surgery can be explained by clinicians applying the same absolute transfusion thresholds irrespective of a patient's gender. This, together with the common use of a liberal transfusion strategy, leads to further overtransfusion in women.

Sex and the Risk of AKI Following Cardio-thoracic Surgery: A Meta-Analysis

BACKGROUND AND OBJECTIVES

Being a woman is a well established risk factor for the development of cardiothoracic surgery-associated AKI. In striking contrast, women are less likely to develop AKI associated with noncardiac surgical procedures than men. In an attempt to ascertain why being a woman might be protective for ischemic AKI after general surgery but deleterious in patients undergoing cardiothoracic surgery, we examined cardiothoracic surgery-associated AKI in greater detail.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We performed a systematic review and meta-analysis of cardiothoracic surgery-associated AKI studies published between January of 1978 and December of 2015 to further explore the relationship between sex and cardiothoracic surgery-associated AKI.

RESULTS

Sixty-four studies were identified that provided sex-specific data regarding the incidence of cardiothoracic surgery-associated AKI among 1,057,412 subjects. Using univariate analysis, women were more likely than men to develop AKI postoperatively (odds ratio, 1.21; 95% confidence interval, 1.09 to 1.33; P<0.001). However, when the analysis was restricted to the 120,464 subjects reported in 29 studies that used the Acute Kidney Injury Network criteria, the RIFLE criteria, or the Kidney Disease Improving Global Outcomes criteria to define AKI, there was no significant sex-related difference in risk. Seventeen studies used multivariate analysis to assess risk factors for cardiothoracic surgery-associated AKI and provided sex-specific odd ratios. Among the 1,587,181 individuals included in these studies, the risk of developing cardiothoracic surgery-associated AKI was not significantly associated with sex (odds ratio, 1.04; 95% confidence interval, 0.92 to 1.19; P=0.51). However, when the analysis was restricted to the 5106 subjects reported in four studies that used the Acute Kidney Injury Network criteria to define AKI, the risk of developing AKI was significantly lower in women compared with in men (odds ratio, 0.75; 95% confidence interval, 0.65 to 0.87; P<0.001).

CONCLUSIONS

Our systematic review and meta-analysis contradict the generally held consensus that being a woman is an independent risk factor for the development of cardiothoracic surgery-associated AKI.

Does a similar procedure result in similar survival for women and men undergoing isolated coronary artery bypass grafting?

OBJECTIVES

To (1) identify sex-related differences in risk factors and revascularization strategies for patients undergoing coronary artery bypass grafting (CABG), (2) assess whether these differences influenced early and late survival, and (3) determine whether clinical effectiveness of the same revascularization strategy was influenced by sex.

METHODS

From January 1972 to January 2011, 57,943 adults-11,009 (19%) women-underwent primary isolated CABG. Separate models for long-term mortality were developed for men and women, followed by assessing sex-related differences in strength of risk factors (interaction terms).

RESULTS

Incomplete revascularization was more common in men than women (26% vs 22%, P < .0001), but women received fewer bilateral internal thoracic artery (ITA) grafts (4.8% vs 12%; P < .0001) and fewer arterial grafts (68% vs 70%; P < .0001). Overall, women had lower survival than men after CABG (65% and 31% at 10 and 20 years, respectively, vs 74% and 41%; P ≤ .0001), even after risk adjustment. Incomplete revascularization was associated equally (P > .9) with lower survival in both sexes. Single ITA grafting was associated with equally (P = .3) better survival in women and men. Although bilateral ITA grafting was associated with better survival than single ITA grafting, it was less effective in women-11% lower late mortality (hazard ratio, 0.89 [0.77-1.022]) versus 27% lower in men (hazard ratio, 0.73 [0.69-0.77]; P = .01).

CONCLUSIONS

Women on average have longer life expectancies than men but not after CABG. Every attempt should be made to use arterial grafting and complete revascularization, but for unexplained reasons, sex-related differences in effectiveness of bilateral arterial grafting were identified.

Sex Differences in the Epidemiology of New-Onset In-Hospital Post-Coronary Artery Bypass Graft Surgery Atrial Fibrillation: A Large Multicenter Study

BACKGROUND

New-onset atrial fibrillation (AF) after coronary artery bypass graft surgery (CABG) is associated with increased morbidity and poorer long-term survival. Although many studies show differences in outcome in women versus men after CABG, little is known about the sex-specific incidence and characteristics of post-CABG AF.

METHODS AND RESULTS

Overall, 11 236 consecutive patients without preoperative AF underwent isolated CABG from 2002 to 2010 at 4 US academic medical centers and 1 high-volume specialty cardiac hospital. Data routinely collected for the Society of Thoracic Surgeons database were augmented with details on new-onset post-CABG AF events detected via continuous in-hospital ECG/telemetry monitoring. Unadjusted incidence of post-CABG AF was 29.5% (3312/11 236) overall, 30.2% (2485/8214) in men, and 27.4% (827/3022) in women. After adjustment for Society of Thoracic Surgeons-recognized risk factors, women had significantly lower risk for post-CABG AF (odds ratio [95% confidence interval]=0.75 [0.64-0.89]), shorter first, longest, and total duration of AF episodes (mean difference [95% confidence interval]=-2.7 [-4.7 to -0.8] hours; -4.1 [-6.9 to -1.2] hours; -2.4 [-2.5 to -2.3] hours, respectively). At 48 hours, AF-free probabilities were 77% for women and 72% for men (P<0.001). Number of episodes (P=0.18), operative mortality (P=0.048), stroke (P=0.126), and discharge in AF (P=0.234) did not differ significantly by sex.

CONCLUSIONS

These novel data on sex-specific characteristics of new-onset AF after isolated CABG show that women had lower adjusted risk for post-CABG AF and experienced shorter episodes. Investigation of sex-specific impacts on outcomes is needed to identify optimal strategies for prevention and management to ensure all patients achieve the best possible outcomes.

Gender differences in outcomes following isolated coronary artery bypass grafting: long-term results

Background

The main purpose of this study was to evaluate the impact of gender on outcomes after isolated coronary artery bypass grafting, in terms of 5-year rates of overall death, cardiac-related death, myocardial infarction, re-hospitalization, repeat percutaneous or surgical revascularization, stroke, new pacemaker implantation, postoperative renal failure, heart failure and need for long-term care.

Methods

Two propensity-score matched cohorts, each of 1331 patients, undergoing isolated surgical coronary revascularization at the regional public and private centers of Emilia-Romagna region (Italy) from January 1st 2003 to December 31th 2013, were used to compare long-term outcomes of male (5976 patients) versus female gender (1332 patients).

Results

In the matched cohort, males received significantly more bypass grafts (3.0 ± 1.0 vs 2.8 ± 1.0, p = 0.001). Left internal mammary artery use and total arterial revascularization were similarly performed in both matched subgroups. Both groups reported similar cumulative rate of all-cause, cardiac-related mortality and stroke at five years. Females experienced significantly higher rate of myocardial infarction, and not significantly higher occurrence of heart failure, and need for long-term care. Males experienced significantly higher rate of cumulative re-hospitalization and higher need for pacemaker implantation. Female gender was not an independent predictor of death at long-term follow-up.

Conclusions

Women are more likely to be readmitted with myocardial infarction and congestive heart failure after CABG but experience survival similar to that observed in men. Female gender was not an independent risk factor for mortality. Prevention of new occurrence of postoperative myocardial infarction and enhancement of complete coronary revascularization should be future endpoints.

Reduced Long-Term Relative Survival in Females and Younger Adults Undergoing Cardiac Surgery: A Prospective Cohort Study

OBJECTIVES

To assess long-term survival and mortality in adult cardiac surgery patients.

METHODS

8,564 consecutive patients undergoing cardiac surgery in Trondheim, Norway from 2000 until censoring 31.12.2014 were prospectively followed. Observed long-term mortality following surgery was compared to the expected mortality in the Norwegian population, matched on gender, age and calendar year. This enabled assessment of relative survival (observed/expected survival rates) and relative mortality (observed/expected deaths). Long-term mortality was compared across gender, age and surgical procedure. Predictors of reduced survival were assessed with multivariate analyses of observed and relative mortality.

RESULTS

During follow-up (median 6.4 years), 2,044 patients (23.9%) died. The observed 30-day, 1-, 3- and 5-year mortality rates were 2.2%, 4.4%, 8.2% and 13.8%, respectively, and remained constant throughout the study period. Comparing observed mortality to that expected in a matched sample from the general population, patients undergoing cardiac surgery showed excellent survival throughout the first seven years of follow-up (relative survival ≥ 1). Subsequently, survival decreased, which was more pronounced in females and patients undergoing other procedures than isolated coronary artery bypass grafting (CABG). Relative mortality was higher in younger age groups, females and patients undergoing aortic valve replacement (AVR). The female survival advantage in the general population was obliterated (relative mortality ratio (RMR) 1.35 (1.19-1.54), p<0.001). Increasing observed long-term mortality seen with ageing was due to population risk, and younger age was independently associated with increased relative mortality (RMR per 5 years 0.81 (0.79-0.84), p<0.001)).

CONCLUSIONS

Cardiac surgery patients showed comparable survival to that expected in the general Norwegian population, underlining the benefits of cardiac surgery in appropriately selected patients. The beneficial effect lasted shorter in younger patients, females and patients undergoing AVR or other procedures than isolated CABG. Thus, the study identified three groups that need increased attention for further improvement of outcomes.

Transcatheter Aortic Valve Replacement in Women Versus Men (from the US CoreValve Trials)

Treatment for severe symptomatic aortic stenosis has changed significantly in recent years due to advances in transcatheter aortic valve replacement (TAVR). Recent studies with the CoreValve prosthesis have demonstrated superior results compared with surgical aortic valve replacement in patients at increased risk for surgery, but there are limited data on gender-related differences in patient characteristics and outcomes with this device. We compared baseline characteristics and clinical outcomes in women and men undergoing TAVR with the CoreValve prosthesis. A total of 3,687 patients (1,708 women and 1,979 men) were included. At baseline, women tended to be slightly older and to have increased frailty, but they had fewer cardiac co-morbidities, higher left ventricular systolic function, less coronary artery disease, and fewer previous strokes. All-cause mortality was 5.9% for women and 5.8% for men at 30 days (p = 0.87) and 24.1% and 21.3%, respectively, at 1 year (p = 0.08). The incidence of stroke was 5.7% in women and 4.0% in men at 30 days (p = 0.02) and 9.3% and 7.7%, respectively, at 1 year (p = 0.05). Women had a higher incidence of bleeding, including more life-threatening bleeds, and a greater incidence of major vascular complications than men at 30 days. Device success was achieved in 86.9% of women and 86.1% of men (p = 0.50). In conclusion, although there were significant baseline differences and procedure-related complications between women and men undergoing TAVR with the CoreValve prosthesis, this analysis found no significant difference in 30-day or 1-year mortality.

Intensive Care Unit Stay of More than 14 Days after Cardiac Surgery is Associated with Non-cardiac Organ Failure

Some studies have shown an association between a prolonged intensive care unit (ICU) stay and risk factors such as mediastinal re-exploration, advanced age, low ejection fraction, lung disease and organ failure. The aim of this retrospective study was first to evaluate peri-operative risk factors ( n = 2683) and secondly to evaluate long-term survival ( n = 2563) in cardiac surgery patients with an ICU stay > 14 days. Long-term survival was assessed in an observational 3-year follow-up study. An ICU stay of > 14 days was associated independently with respiratory failure and dialysis-dependent acute renal failure, and with a significantly lower survival rate. Since an ICU stay is associated with a higher hospital and long-term mortality, measures should be taken throughout the entire hospital stay to identify and reduce the risk of organ failure.

Excess short-term mortality in women after isolated coronary artery bypass graft surgery

Objective

Female sex is considered a risk factor for adverse outcomes following isolated coronary artery bypass graft (CABG) surgery. We assessed the association between sex and short-term mortality following isolated CABG, and estimated the ‘excess’ deaths occurring in women.

Methods

Short-term mortality was investigated in 13 327 consecutive isolated CABG patients in North Texas between January 2008 and December 2012. The association between sex and CABG short-term mortality, and the excess deaths among women were assessed via a propensity-adjusted (by Society of Thoracic Surgeons-recognised risk factors) generalised estimating equations model approach.

Results

Short-term mortality was significantly higher in women than men (adjusted OR=1.39; 95% CI 1.04 to 1.86; p=0.027). This significantly greater risk translates into 35 ‘excess’ deaths among women included in this study (>10% of the total 343 deaths in the study cohort) and into 392 ‘excess’ deaths among the ∼40 000 women undergoing isolated CABG in the USA each year.

Conclusions

The higher risk associated with female sex lead to 35 ‘excess’ deaths in women in this study cohort (over 10% of the total deaths) and to 392 ‘excess’ deaths among women undergoing isolated CABG in the USA each year. Further research is needed to assess the causal mechanisms underlying this sex-related difference. Results of such work could inform the development and implementation of sex-specific treatment and management strategies to reduce women's mortality following CABG. Based on our results, if such work brought women's short-term mortality into line with men's, total short-term mortality could be reduced by up to 10%.

Effect of gender and race on operative mortality after isolated coronary artery bypass grafting

Studies examining outcomes after coronary artery bypass grafting (CABG) by gender and/or race have shown conflicting results. It remains to be determined if, or how, gender and race are independent risk factors for CABG operative mortality. Using all consecutive patients who underwent isolated CABG at Baylor University Medical Center in Dallas, Texas, from January 2004 to October 2011, the risk-adjusted associations between gender and race, respectively, and operative mortality were estimated using a generalized propensity approach, accounting for recognized Society of Thoracic Surgeons risk factors for mortality. Women were nearly 2 times more likely to die during or within 30 days of the operation than men (odds ratio 1.96, 95% confidence interval 1.44 to 2.66, p <0.0001), while no significant mortality differences were observed among races. In conclusion, these findings suggest that women face a significantly greater risk for operative death that should be taken into account during the treatment decision-making process but that race is not associated with CABG mortality and so should not be among the factors considered.

Long-term outcome in men and women after CABG; results from the IMAGINE trial

BACKGROUND

The aim of this study is to determine sex differences in long-term outcome after coronary artery bypass grafting (CABG).

METHODS

The international randomized controlled IMAGINE study included 2553 consecutive patients with a left ventricular ejection fraction of >40% who underwent isolated CABG. Median follow-up was 32 months (IQR 17-42 months). The composite endpoint comprised of death, myocardial infarction (MI), cerebrovascular event, angina, revascularization and congestive heart failure. Cox regression analysis was used to examine sex differences in outcome post-CABG.

RESULTS

Of the 2553 patients, 2229 were men and 324 (13%) were women. Women were older and more often reported diabetes and hypertension. Smoking and impaired renal function were more prevalent in men. Women experienced a higher event rate during follow-up (composite endpoint 18% vs 12%; P = 0.007). Cox regression showed an increased risk of the composite endpoint in women after adjustment for age (HR 1.48 (95% CI: 1.11-1.97)) which was non-significant after additional adjustment for other confounders (HR 1.26 (95% CI: 0.92-1.72)).

CONCLUSION

Women have a worse long-term outcome after CABG than men in univariate analysis. However, after adjusting for potential confounders female sex became a non-significant predictor for prognosis, possibly due to the small sample size of women. Definite answers regarding sex-differences in long-term outcome after CABG should come from future pooling of studies comprising a larger number of women.

Safety and efficacy of percutaneous mitral valve repair using the MitraClip® system in patients with diabetes mellitus

BACKGROUND

Patients with diabetes mellitus show a negative outcome in percutaneous coronary intervention, aortic valve replacement and cardiac surgery. The impact of diabetes on patients undergoing treatment of severe mitral regurgitation (MR) using the MitraClip system is not known. We therefore sought to assess whether percutaneous mitral valve repair with the MitraClip system is safe and effective in patients with diabetes mellitus.

METHODS AND RESULTS

We included 58 patients with severe and moderate-to-severe MR in an open-label observational single-center study. Ninteen patients were under oral medication or insulin therapy for type II diabetes mellitus. MitraClip devices were successfully implanted in all patients with diabetes and in 97.4% (n = 38) of patients without diabetes (p = 0.672). Periprocedural major cardiac adverse and cerebrovascular events (MACCE) occurred in 5.1% (n = 2) of patients without diabetes whereas patients with diabetes did not show any MACCE (p = 0.448). 30-day mortality was 1.7% (n = 1) with no case of death in the diabetes group. Short-term follow up of three months showed a significant improvement of NYHA class and quality of life evaluated by the Minnesota Living with Heart Failure Questionnaire in both groups, with no changes in the 6-minute walk test.

CONCLUSIONS

Mitral valve repair with the MitraClip system is safe and effective in patients with type II diabetes mellitus.

TRIAL REGISTRATION

MitraClip Registry NCT02033811.

Prevalence of preoperative anaemia in patients having first-time cardiac surgery and its impact on clinical outcome. A retrospective observational study

The prevalence of anaemia is increasing globally. It has a close association with perioperative blood transfusion which, in turn, results in an increased risk of postoperative complications. Undesirable effects are not only limited to short-term, but also have long-term implications. Despite this, many patients undergo cardiac surgery with undiagnosed and untreated anaemia. We designed a retrospective, observational study to estimate the prevalence of anaemia in patients having cardiac surgery in Auckland District Health Board, blood transfusion rates and associated clinical outcome. Two hundred of seven hundred and twelve (28.1%) patients were anaemic. Red blood cell (RBC) transfusion rates were significantly higher in the anaemic group compared to the non-anaemic group (160 (80%) vs. 192 (38%), p-value <0.0001, RR (CI 95%) 2.133 (1.870-2.433)). Transfusion rates for fresh frozen plasma (FFP), cryoprecipitate and platelets were also higher in the anaemic group. Anaemia was significantly associated with the development of new infection (14 (7%) vs. 15 (2.9%), p-value 0.0193, RR (CI 95%) 2.389 (1.175-4.859)), prolonged ventilation time (47.01 hours vs. 23.59 hours, p-value 0.0076) and prolonged intensive care unit (ICU) stay (80.23 hours vs. 50.27, p-value 0.0011). Preoperative anaemia is highly prevalent and showed a clear link with significantly higher transfusion rates and postoperative morbidity. It is vital that a preoperative management plan for the correction of anaemia should be sought to improve patient safety and outcome.

Off-pump versus on-pump revascularization in females: a meta-analysis of observational studies

BACKGROUND

Coronary revascularization in female patients presents several challenges, including smaller target vessels and smaller conduits. Furthermore, late presentation and more co-morbidities than males may increase complication rates. The aim of this study was to assess whether off-pump coronary artery bypass (OPCAB) improves outcomes when compared to on-pump coronary artery bypass (ONCAB) in the female population.

METHODS

A systematic literature review identified six observational studies, incorporating 23313 patients (n=9596 OPCAB, 13717 ONCAB). These were meta-analyzed using random effects modeling. Heterogeneity, subgroup analysis, quality scoring and publication bias were assessed. The primary endpoints were 30-day mortality and major cardiac, respiratory and renal complications. Secondary endpoints were the number of grafts per patient.

RESULTS

No statistically significant difference was observed in 30-day mortality between the OPCAB and ONCAB groups (4.8% vs. 0.7%; OR 0.96; 95% CI [0.41, 2.24], p=0.92). Significant inter-study heterogeneity was also present (I2=94%) and was not explained by study size or quality. Peri-operative myocardial infarction (OR 0.65; 95% CI [0.51, 0.84], p=0.0009) was significantly lower with OPCAB without significant heterogeneity; however, OPCAB did not significantly alter other morbidity outcomes. OPCAB was associated with a trend towards fewer grafts per patient than ONCAB.

CONCLUSIONS

OPCAB is a safe alternative to ONCAB in the surgical revascularisation of female patients and may reduce post-operative myocardial infarction (MI). However, this does not translate into a reduction in 30-day mortality and OPCAB does not significantly improve other cardiovascular, renal or neurological outcomes. Late outcome data remains lacking and a well-structured, randomized trial is required to answer vital questions regarding the effect of OPCAB on women in the long-term.

Acute kidney injury after coronary artery bypass grafting and long-term risk of myocardial infarction and death

BACKGROUND

Acute kidney injury (AKI) after coronary artery bypass grafting (CABG) is associated with early mortality. Its impact on the risk of myocardial infarction (MI) over time and long-term mortality has not been well described.

METHODS

We performed a nationwide population-based cohort study in 27,929 patients who underwent a first isolated CABG between 2000 and 2008 in Sweden. Acute kidney injury was divided into three categories based on the absolute increase in postoperative serum creatinine (sCr) concentration compared with the preoperative baseline: stage 1, sCr increase of 0.3 to 0.5mg/dL; stage 2, sCr increase of >0.5 to 1.0mg/dL and stage 3, sCr increase of ≥ 1.0mg/dL.

RESULTS

The overall incidence of postoperative AKI was 13%, 6.3% met the criterion for stage 1, 4.3% for stage 2 and 2.3% for stage 3. During a mean follow-up of 5.0 years, there were 2119 (7.6%) MIs and 4679 (17%) deaths. Multivariable adjusted hazard ratios with 95% confidence intervals for MI were 1.35 (1.15 to 1.57), 1.80 (1.53 to 2.13) and 1.63 (1.29 to 2.07), in AKI stages 1, 2 and 3, respectively. The corresponding hazard ratios for all-cause mortality were 1.30 (1.17 to 1.44), 1.65 (1.48 to 1.83) and 2.68 (2.37 to 3.03), respectively.

CONCLUSIONS

Our results show that AKI after CABG is associated with an increased long-term risk of MI and death.

Relationship between gender and in-hospital morbidity and mortality after coronary artery bypass grafting surgery in an Iranian population

Background:

Many previous studies have investigated the influence of gender on coronary artery bypass grafting surgery (CABG) outcomes. Despite the great volume of reports on this issue, it is still not clear whether it is the gender of the patient or pre-existing comorbid conditions that is the best predictor for the different outcomes seen between men and women. Multiple studies have shown that women are at higher risk of postoperative complications than men, particularly in the perioperative period.

Objectives:

The goal of this study was to determine whether sex differences exist in preoperative variables between men and women, and to evaluate the effect of gender on short-term mortality and morbidity after CABG in an Iranian population.

Patients and Methods:

Data were collected prospectively from 690 consecutive patients (495 men and 195 women) who underwent isolated CABG. Preoperative, intraoperative, and postoperative variables, major complications and death were compared between the male and female patients until hospital discharge using multivariate analysis.

Results:

Women were older (P = 0.020), had more diabetes (P = 0.0001), more obesity (P = 0.010), a higher New York Heart Association functional class (P = 0.030), and there was less use of arterial grafts (P = 0.016). Men had more tobacco smokers (P = 0.0001) and lower preoperative ejection fractions (EF) (P = 0.030). After surgery, women had a higher incidence of respiratory complications (P = 0.003), higher creatine kinase (CK) – MB levels (P = 0.0001), and higher inotropic support requirements (P = 0.030). They also had a higher incidence of decreased postoperative EF versus preoperative values (P = 0.020). The length of ICU stay, incidence of return to ICU and postoperative death, were similar between men and women. Nevertheless, after adjusting for age and diabetes, female gender was still independently associated with higher morbidity in patients over 50 years of age.

Conclusions:

Women had more risk factors, comorbidities, and postoperative complications. Women older than 50 years of age were at a higher risk of postoperative complications than men. This difference decreased with younger age. In-hospital mortality rates were not influenced by sex, as there was no difference found between the two groups (2.5% women vs. 2.2% men; P > 0.05).

Association of gender with outcomes in critically ill patients

Introduction

The influence of gender on mortality and other outcomes of critically ill patients is not clear. Different studies have been performed in various settings and patient populations often yielding conflicting results. We wanted to assess the relationship of gender and intensive care unit (ICU) outcomes in the patients included in the Acute Physiology and Chronic Health Evaluation (APACHE) IV database (Cerner Corporation, USA).

Methods

We performed a retrospective review of the data available in the APACHE IV database. A total of 261,255 consecutive patients admitted to adult ICUs in United States from 1 January 2004 to 31 December 2008 were included. Readmissions were excluded from the analysis. The primary objective of the study was to assess the relationship of gender with ICU mortality. The secondary objective was to evaluate the association of gender with active therapy, mechanical ventilation, length of stay in the ICU, readmission rate and hospital mortality. The gender-related outcomes for disease subgroups including acute coronary syndrome, coronary artery bypass graft (CABG) surgery, sepsis, trauma and chronic obstructive pulmonary disease (COPD) exacerbation were assessed as well.

Results

ICU mortality was 7.2% for men and 7.9% for women, odds ratio (OR) for death for women was 1.07 (95% confidence interval (CI): 1.04 to 1.1). There was a statistically significant interaction between gender and age. In patients <50 years of age, women had a reduced ICU mortality compared with men, after adjustment for acute physiology score, ethnicity, co-morbid conditions, pre-ICU length of stay, pre-ICU location and hospital teaching status (adjusted OR 0.83, 95% CI: 0.76 to 0.91). But among patients ≥50 years of age, there was no significant difference in ICU mortality between men and women (adjusted OR 1.02, 95% CI: 0.98 to 1.06).

A higher proportion of men received mechanical ventilation, emergent surgery, thrombolytic therapy and CABG surgery. Men had a higher readmission rate and longer length of ICU stay. The adjusted mortality of women compared to men was higher with CABG, while it was lower with COPD exacerbation. There was no significant difference in mortality in acute coronary syndrome, sepsis and trauma.

Conclusions

Among the critically ill patients, women less than 50 years of age had a lower ICU mortality compared to men, while 50 years of age or older women did not have a significant difference compared to men. Women had a higher mortality compared to men after CABG surgery and lower mortality with COPD exacerbation. There was no difference in mortality in acute coronary syndrome, sepsis or trauma.

Gender gap in acute coronary heart disease: Myth or reality?

AIM

To investigate potential gender differences in the prevalence of cardiovascular risk factors, cardiovascular disease (CVD) management, and prognosis in acute coronary syndrome (ACS).

METHODS

A systematic literature search was performed through Medline using pre-specified keywords. An additional search was performed, focusing specifically on randomized controlled clinical trials in relation to therapeutic intervention and prognosis. In total, 92 relevant articles were found.

RESULTS

Women with CVD tended to have more hypertension and diabetes at the time of presentation, whereas men were more likely to smoke. Coronary angiography and revascularization by percutaneous coronary intervention were performed more often in men. Women were at a greater risk of short-term mortality and complications after revascularization. Interestingly, women under 40 years presenting with ACS were at highest risk of cardiovascular death compared with men of the same age, irrespective of risk factors. This disadvantage disappeared in older age. The long-term mortality risk of ACS was similar in men and women, and even in favor of women.

CONCLUSION

Mortality rates are higher among young women with ACS, but this difference tends to disappear with age, and long-term prognosis is even better among older women.

Gender's impact on outcome in coronary surgery with minimized extracorporeal circulation

BACKGROUND

The role of female gender in cardiac surgery is still controversial. We examined the impact of gender on mortality after coronary artery bypass grafting (CABG) with minimized extracorporeal circulation (MECC).

METHODS

Between January 2004 and May 2009, 1,662 patients (439 females, 1,223 males) underwent CABG with MECC at the University Medical Center Regensburg. Perioperative data were retrospectively analyzed; primary end point was in-hospital mortality.

RESULTS

At operation, women were older, had a higher prevalence of diabetes and impaired renal function, and underwent more often non-elective surgery. Unadjusted mortality was significantly lower for men and than for women (2.3 vs. 5.7%; p = 0.001). Risk-adjusted mortality rates were derived by stepwise logistic regression. The final model reduced the gender-related mortality gap from 147 to 32%. Goodness of fit and discriminatory performance (AUC = 0.83) were good. Female gender, however, could not be identified as an independent risk factor for adverse outcome (OR 1.6; 95% CI 0.8-3.4). Risk-adjusted mortality was calculated as 4.9% in females and 2.6% in males. Low body surface area (<1.66 m(2)) was associated with excess mortality in females.

CONCLUSIONS

Gender-related disparity in outcome still remains present after surgery with minimized extracorporeal circulation. However, female gender per se is not an independent risk factor for in-hospital mortality, but close attention should be paid on modifiable risk factors.

Female gender and the risk for death after cardiac surgery in septuagenarians and octogenarians: a retrospective observational study

BACKGROUND

In elderly patients, the impact of gender on outcome after cardiac surgery is a debated topic of ongoing relevance.

OBJECTIVE

This study assessed the hypothesis that, among septuagenarians and octogenarians, women have poorer outcomes compared with men after cardiac surgery.

METHODS

For this retrospective observational study, the electronic medical records of patients who underwent cardiac surgery between January 2006 and August 2009 at Department of Cardiothoracic Surgery, University Medical Center, Regensburg, Germany, were reviewed. The primary end points were the proportions of women and men with in-hospital and 30-day mortality, and postoperative morbidity was considered a secondary end point.

RESULTS

The records of 598 patients were reviewed (274 female [137 septuagenarians, 162 octogenarians; mean (SD)] age, 77.8 [4.8] years]; 324 male [137 septuagenarians, 162 octogenarians; mean age, 78.3 [4.8] years]; all, P = NS). At baseline, the gender groups differed significantly with respect to mean logistic European System for Cardiac Operative Risk Evaluation score (EuroSCORE) (used for calculating expected mortality) (11.9% in women, 9.9% in men; P = 0.007), rate of diabetes mellitus did not reach statistical significance ([statistical significance was considered at P < 0.05] 12.4% vs 7.4%; P = 0.052), rate of renal dysfunction (51.5% vs 28.6%; P < 0.001), proportion undergoing isolated valve surgery (43.1% vs 24.7%, respectively; P < 0.0001), and perfusion technique (conventional [83.2% vs 69.4%] vs minimized [16.8% vs 30.6%] extracorporeal circulation) (P < 0.0001). In-hospital mortality (7.3% vs 5.6%; P = 0.404) and 30-day mortality (8.0% vs 5.9%; P = 0.332) were not significantly different between genders. There were no significant differences in mortality with respect to age group. On multivariate analysis, age and female gender were not found to be independent risk factors for early mortality. The between-gender differences in postoperative morbidity, including central neurologic event (P = 0.412), need for dialysis (P = 0.491), and respiratory insufficiency (P = 1.00), were nonsignificant, as were median durations of intensive care unit stay (P = 0.68) and hospital stay (P = 0.52) stay.

CONCLUSION

In septuagenarians and octogenarians, female gender was not associated with increased risks for morbidity and mortality after cardiac surgery.

Effects of sex, body mass index, and body size on the outcome of coronary artery bypass surgery: Iranian experience

OBJECTIVE

Sex, body mass index, and body surface area have been proposed as important determinants of outcome after coronary artery bypass graft surgery.

METHODS

In a retrospective study, the archived files of the patients who had undergone isolated coronary artery bypass graft (CABG) in our center from January 2005 to September 2008 were evaluated. The data regarding the patients' body surface area (BSA), body mass index (BMI), and laboratory tests as well as their demographic data and the number of deaths, duration of intensive care unit (ICU) stay, and duration of hospital admissions were collected. Duration of ICU stay >4 days and death were considered for the final outcomes to present the morbidity and mortality, respectively.

RESULTS

In total, the files of 1223 patients were reviewed. BSA was different between men and women, but the differences in mortality and morbidity were not statistically significant. The difference between the mean BMI in men and women was not significant (P = 0.72). In all, 11 patients (9 men, 2 women) died during the hospital stay, but no significant difference was observed between the men and the women (P = 0.59). Among the patients, 6.5% stayed >4 days in the ICU (50 men, 20 women) with no significant difference between the two (P = 0.482). No significant differences were found between the BSA and BMI of the patients who died and those who were discharged from the hospital (P = 0.088 and P = 0.321, respectively). There were no significant correlations between the duration of hospital stay and the BSA or BMI (P = 0.44 and P = 0.26, respectively).

CONCLUSION

Sex, BMI, and BSA do not affect the outcome after CABG.