Predictors of long-term survival after coronary artery bypass grafting surgery: results from the Society of Thoracic Surgeons Adult Cardiac Surgery Database (the ASCERT study)

Long-Term Mortality Risk According to Cardiorespiratory Fitness in Patients Undergoing Coronary Artery Bypass Graft Surgery

The aim of this study was to evaluate the association between cardiorespiratory fitness (CRF) and long-term survival in United States (US) Veterans undergoing CABG. We identified 14,550 US Veterans who underwent CABG at least six months after completing a symptom-limited exercise treadmill test (ETT) with no evidence of cardiovascular disease. During a mean follow-up period of 10.0 ± 5.4 years, 6502 (43.0%) died. To assess the association between CRF and risk of mortality, we formed the following five fitness categories based on peak workload achieved (metabolic equivalents or METs) prior to CABG: Least-Fit (4.3 ± 1.0 METs (n = 4722)), Low-Fit (6.8 ± 0.9 METs (n = 3788)), Moderate-Fit (8.3 ± 1.1 METs (n = 2608)), Fit (10.2 ± 0.8 METs (n = 2613)), and High-Fit (13.0 ± 1.5 METs (n = 819)). Cox proportional hazard models were used to calculate risk across CRF categories. The models were adjusted for age, body mass index, race, cardiovascular disease, percutaneous coronary intervention prior to ETT, cardiovascular medications, and cardiovascular disease risk factors. P-values < 0.05 using two-sided tests were considered statistically significant. The association between cardiorespiratory fitness and mortality was inverse and graded. For every 1-MET increase in exercise capacity, the mortality risk was 11% lower (HR = 0.89; CI: 0.88-0.90; p < 0.001). When compared to the Least-Fit category (referent), mortality risk was 22% lower in Low-Fit individuals (HR = 0.78; CI: 0.73-0.82; p < 0.001), 31% lower in Moderate-Fit individuals (HR = 0.69; CI: 0.64-0.74; p < 0.001), 52% lower in Fit individuals (HR = 0.48; CI: 0.44-0.52; p < 0.001), and 66% lower in High-Fit individuals (HR = 0.34; CI: 0.29-0.40; p < 0.001). Cardiorespiratory fitness is inversely and independently associated with long-term mortality after CABG in Veterans referred for exercise testing.

Risk Prediction Models for Long-Term Survival after Cardiac Surgery: A Systematic Review

BACKGROUND

The reporting of alternative postoperative measures of quality after cardiac surgery is becoming increasingly important as in-hospital mortality rates continue to decline. This study aims to systematically review and assess risk models designed to predict long-term outcomes after cardiac surgery.

METHODS

The MEDLINE and Embase databases were searched for articles published between 1990 and 2020. Studies developing or validating risk prediction models for long-term outcomes after cardiac surgery were included. Data were extracted using checklists for critical appraisal and systematic review of prediction modeling studies.

RESULTS

Eleven studies were identified for inclusion in the review, of which nine studies described the development of long-term risk prediction models after cardiac surgery and two were external validation studies. A total of 70 predictors were included across the nine models. The most frequently used predictors were age (n = 9), peripheral vascular disease (n = 8), renal disease (n = 8), and pulmonary disease (n = 8). Despite all models demonstrating acceptable performance on internal validation, only two models underwent external validation, both of which performed poorly.

CONCLUSION

Nine risk prediction models predicting long-term mortality after cardiac surgery have been identified in this review. Statistical issues with model development, limited inclusion of outcomes beyond 5 years of follow-up, and a lack of external validation studies means that none of the models identified can be recommended for use in contemporary cardiac surgery. Further work is needed either to successfully externally validate existing models or to develop new models. Newly developed models should aim to use standardized long-term specific reproducible outcome measures.

Residential Greenness and Long-term Mortality Among Patients Who Underwent Coronary Artery Bypass Graft Surgery

BACKGROUND

Studies have reported inverse associations between exposure to residential greenness and mortality. Greenness has also been associated with better surgical recovery. However, studies have had small sample sizes and have been restricted to clinical settings. We investigated the association between exposure to residential greenness and all-cause mortality among a cohort of cardiac patients who underwent coronary artery bypass graft (CABG) surgery.

METHODS

We studied this cohort of 3,128 CABG patients between 2004 and 2009 at seven cardiothoracic departments in Israel and followed patients until death or 1st May 2021. We collected covariate information at the time of surgery and calculated the patient-level average normalized difference vegetation index (NDVI) over the entire follow-up in a 300 m buffer from the home address. We used Cox proportional hazards regression models to estimate associations between greenness and death, adjusting for age, sex, origin, socioeconomic status, type of hospital admission, peripherality, air pollution, and distance from the sea.

RESULTS

Mean age at surgery was 63.8 ± 10.6 for men and 69.5 ± 10.0 for women. During an average of 12.1 years of follow-up (37,912 person-years), 1,442 (46%) patients died. A fully adjusted Cox proportional hazards model estimated a 7% lower risk of mortality (HR: 0.93, 95% CI = [0.85, 1.00]) per 1 interquartile range width increase (0.04) in NDVI. Results were robust to the use of different buffer sizes (100 m-1,250 m from the home) and to the use of average NDVI exposure during the first versus the last 2 years of follow-up.

CONCLUSIONS

Residential greenness was associated with lower risk of mortality in CABG patients.

The impact of telenursing on level of depression, stress and anxiety in discharged patients after coronary artery bypass graft surgery: A randomized clinical trial

BACKGROUND

After coronary artery bypass graft surgery patients are susceptible to mental disorders such as stress, anxiety, and depression following discharge from the hospital and often require post-discharge support and follow-up. Telenursing is an accessible method that may reduce stress, anxiety, and depression experienced by patients. This study aimed to investigate the impact of telenursing on depression, stress, and anxiety in discharged patients after CABG surgery.

MATERIALS AND METHODS

A randomized clinical trial was carried out. Eligible patients were divided randomly into intervention (n=40) and control (n=40) groups. Depression Anxiety Stress Scale-21 (DASS21) questionnaire was filled out by both groups one day before discharge from the hospital. The intervention group received SMS reminders of their treatment plan, referrals to the cardiac rehabilitation clinic, and routine care three times a week for six weeks, while the control group received routine care provided by the hospital only. In the week following the completion of the intervention period, both groups returned to fill out the questionnaire, and the data were analyzed using SPSS version 16.0, descriptive and inferential statistics, and independent and paired T-tests.

RESULT

The mean scores of depression, stress, and anxiety before intervention in the intervention group were 11.95, 18.75, and 18.17, and in the control group were 11.55, 18.37, and 17.4 respectively. The mean scores of depression, stress, and anxiety after intervention in the intervention group were 7.85, 10.5, and 10.45, and in the control group were 10.56, 17.9, and 16.5 respectively. No significant differences were seen between the two groups before the intervention (P>0.05), but the results showed significant differences between the two groups' mean scores of depression, stress, and anxiety after intervention (P<0.001).

CONCLUSION

Telenursing can reduce stress, anxiety, and depression in discharged patients after coronary artery bypass graft surgery by providing proper and cost-effective follow-up.

Mobile health for cardiovascular risk management after cardiac surgery: results of a sub-analysis of The Box 2.0 study

Aims

Lowering low-density lipoprotein (LDL-C) and blood pressure (BP) levels to guideline recommended values reduces the risk of major adverse cardiac events in patients who underwent coronary artery bypass grafting (CABG). To improve cardiovascular risk management, this study evaluated the effects of mobile health (mHealth) on BP and cholesterol levels in patients after standalone CABG.

Methods and results

This study is a post hoc analysis of an observational cohort study among 228 adult patients who underwent standalone CABG surgery at a tertiary care hospital in The Netherlands. A total of 117 patients received standard care, and 111 patients underwent an mHealth intervention. This consisted of frequent BP and weight monitoring with regimen adjustment in case of high BP. Primary outcome was difference in systolic BP and LDL-C between baseline and value after three months of follow-up. Mean age in the intervention group was 62.7 years, 98 (88.3%) patients were male. A total of 26 449 mHealth measurements were recorded. At three months, systolic BP decreased by 7.0 mmHg [standard deviation (SD): 15.1] in the intervention group vs. -0.3 mmHg (SD: 17.6; P < 0.00001) in controls; body weight decreased by 1.76 kg (SD: 3.23) in the intervention group vs. -0.31 kg (SD: 2.55; P = 0.002) in controls. Serum LDL-C was significantly lower in the intervention group vs. controls (median: 1.8 vs. 2.0 mmol/L; P = 0.0002).

Conclusion

This study showed an association between home monitoring after CABG and a reduction in systolic BP, body weight, and serum LDL-C. The causality of the association between the observed weight loss and decreased LDL-C in intervention group patients remains to be investigated.

The synergistic effect of the triglyceride-glucose index and serum uric acid on the prediction of major adverse cardiovascular events after coronary artery bypass grafting: a multicenter retrospective cohort study

BACKGROUND

Elevated serum uric acid (SUA) is regarded as a risk factor for the development of cardiovascular diseases. Triglyceride-glucose (TyG) index, a novel surrogate for insulin resistance (IR), has been proven to be an independent predictor for adverse cardiac events. However, no study has specifically focused on the interaction between the two metabolic risk factors. Whether combining the TyG index and SUA could achieve more accurate prognostic prediction in patients undergoing coronary artery bypass grafting (CABG) remains unknown.

METHODS

This was a multicenter, retrospective cohort study. A total of 1225 patients who underwent CABG were included in the final analysis. The patients were grouped based on the cut-off value of the TyG index and the sex-specific criteria of hyperuricemia (HUA). Cox regression analysis was conducted. The interaction between the TyG index and SUA was estimated using relative excess risk due to interaction (RERI), attributable proportion (AP), and synergy index (SI). The improvement of model performance yielded by the inclusion of the TyG index and SUA was examined by C-statistics, net reclassification improvement (NRI) and integrated discrimination improvement (IDI). The goodness-of-fit of models was evaluated using the Akaike information criterion (AIC), Bayesian information criterion (BIC) and χ² likelihood ratio test.

RESULTS

During follow-up, 263 patients developed major adverse cardiovascular events (MACE). The independent and joint associations of the TyG index and SUA with adverse events were significant. Patients with higher TyG index and HUA were at higher risk of MACE (Kaplan-Meier analysis: log-rank P < 0.001; Cox regression: HR = 4.10; 95% CI 2.80-6.00, P < 0.001). A significant synergistic interaction was found between the TyG index and SUA [RERI (95% CI): 1.83 (0.32-3.34), P = 0.017; AP (95% CI): 0.41 (0.17-0.66), P = 0.001; SI (95% CI): 2.13 (1.13-4.00), P = 0.019]. The addition of the TyG index and SUA yielded a significant improvement in prognostic prediction and model fit [change in C-statistic: 0.038, P < 0.001; continuous NRI (95% CI): 0.336 (0.201-0.471), P < 0.001; IDI (95% CI): 0.031 (0.019-0.044), P < 0.001; AIC: 3534.29; BIC: 3616.45; likelihood ratio test: P < 0.001).

CONCLUSIONS

The TyG index interacts synergistically with SUA to increase the risk of MACE in patients undergoing CABG, which emphasizes the need to use both measures concurrently when assessing cardiovascular risk.

Development of a Bariatric Surgery Core Data Set for an International Registry

PURPOSE

Bariatric and metabolic surgery is an effective treatment for severe and complex obesity; however, robust long-term data comparing operations is lacking. Clinical registries complement clinical trials in contributing to this evidence base. Agreement on standard data for bariatric registries is needed to facilitate comparisons. This study developed a Core Registry Set (CRS) - core data to include in bariatric surgery registries globally.

MATERIALS AND METHODS

Relevant items were identified from a bariatric surgery research core outcome set, a registry data dictionary project, systematic literature searches, and a patient advisory group. This comprehensive list informed a questionnaire for a two-round Delphi survey with international health professionals. Participants rated each item's importance and received anonymized feedback in round 2. Using pre-defined criteria, items were then categorized for voting at a consensus meeting to agree the CRS.

RESULTS

Items identified from all sources were grouped into 97 questionnaire items. Professionals (n = 272) from 56 countries participated in the round 1 survey of which 45% responded to round 2. Twenty-four professionals from 13 countries participated in the consensus meeting. Twelve items were voted into the CRS including demographic and bariatric procedure information, effectiveness, and safety outcomes.

CONCLUSION

This CRS is the first step towards unifying bariatric surgery registries internationally. We recommend the CRS is included as a minimum dataset in all bariatric registries worldwide. Adoption of the CRS will enable meaningful international comparisons of bariatric operations. Future work will agree definitions and measures for the CRS including incorporating quality-of-life measures defined in a parallel project.

Coronary artery bypass grafting vs. percutaneous coronary intervention in coronary artery disease patients with advanced chronic kidney disease: A Chinese single-center study

Objectives

Aims to compare the contemporary and long-term outcomes of coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) in coronary artery disease (CAD) patients with advanced chronic kidney disease (CKD).

Methods

823 CAD patients with advanced CKD (eGFR < 30 ml/min/1.73 m²) were collected, including 247 patients who underwent CABG and 576 patients received PCI from January 2014 to February 2021. The primary endpoint was all-cause death. The secondary endpoints included major adverse cardiac and cerebrovascular events (MACCEs), myocardial infarction (MI), stroke and revascularization.

Results

Multivariable Cox regression models were used and propensity score matching (PSM) was also performed. After PSM, the 30-day mortality rate in the CABG group was higher than that in the PCI group but without statistically significant (6.6% vs. 2.4%, p = 0.24). During the first year, patients referred for CABG had a hazard ratio (HR) of 1.42 [95% confidence interval (CI), 0.41-3.01] for mortality compared with PCI. At the end of the 5-year follow-up, CABG group had a HR of 0.58 (95%CI, 0.38-0.86) for repeat revascularization, a HR of 0.77 (95%CI, 0.52-1.14) for survival rate and a HR of 0.88(95%CI, 0.56-1.18) for MACCEs as compared to PCI.

Conclusions

Among patients with CAD and advanced CKD who underwent CABG or PCI, the all-cause mortality and MACCEs were comparable between the two groups in 30 days, 1-year and 5 years. However, CABG was only associated with a significantly lower risk for repeat revascularization compared with PCI at 5 years follow-up.

Predictors of Long-Term Outcomes after Surgical Myocardial Revascularization

High mortality from cardiovascular diseases (CVD) requires improved approaches to the treatment of this socially significant pathology. Wide implementation of surgical myocardial revascularization makes it possible to improve significantly both life quality and expectancy in patients with coronary heart disease. The aim of this work was to analyze the literature on the impact of preoperative, operative and postoperative factors on the long-term prognosis after coronary artery bypass grafting (CABG). The review refers to both recent and earlier informative works. The target groups for this article are therapists, cardiologists, rehabilitologists, who work with patients in the short and long term after CABG. Data of Russian and foreign literature show that the long-term prognosis after CABG is largely determined by preoperative factors, in particular – age, set of cardiovascular risk factors (RF) and comorbidity, specifically – severity of coronary and systemic atherosclerosis, incident cardiovascular complications, structural and functional state of the heart. In the aggregate these factors reflect the cumulative effect and further potential of actual cardiovascular RFs, affect longterm risk of adverse events, and determine the therapeutic targets of secondary prevention. Priority of arterial conduits and completeness of revascularization are the main operative factors that determine the course of the long-term period after CABG. Among the postoperative factors, the efficiency of secondary CVD prevention is of paramount importance, in particular – achievement of target RF levels, compensation of cardiac and extracardiac pathology, adherence to the long-term medical therapy, known to improve outcomes based on specific comorbidity. Efficiency of secondary CVD prevention largely depends on patient's health attitudes, the key influence on which beyond attending physician can be provided by participation in rehabilitation programs, teaching patients the meaning and essentials of lifestyle modification and cardiovascular RFs’ control.

Differences in gender and outcomes following isolated coronary artery bypass graft (CABG) surgery

BACKGROUND

Gender impacts pre-, intra-, and postoperative parameters and outcomes following coronary artery bypass graft (CABG) with conflicting results. This study aimed to identify differences in preoperative, intraoperative, and postoperative parameters. It also seeks to compare the postoperative complications and mortality between two genders who had CABG surgery.

METHOD

This prospective observational study included patients who had isolated CABG and were divided based on gender. Demographic information, underlying comorbidities, drug history, clinical and laboratory data at the time of referral, operative characteristics, postoperative variables, and mortality outcomes were tracked during hospitalization and six months after discharge.

RESULTS

Three hundred twenty patients were enrolled in the study during its duration. 71% were male. Women were older (62.40±9.03 vs. 59.99±9.81 years, p= 0.011) and had more dyslipidemia (p=0.003), hypertension (p=0.000), and diabetes (p=0.001), whereas men admitted with more myocardial infarction (MI) (p=0.011) and had lower Ejection fraction (EF) (p=0.001). They also had lower EF post-surgery (p <0.001) and six months after discharge (p = 0.006). However, the number of vessels involved was not different between genders (p=0.589), but the number of grafts was higher in men (p=0.008).There was no statistically significant difference in overall mortality rates between the two groups (4.42% and 6.38% in men and women, respectively, p= 0.464).

CONCLUSIONS

The women had more underlying comorbidities than men. Furthermore, there were some differences in the intra-operative parameters and postoperative complications between the two genders, but there was no difference in postoperative mortality in our setting.

Diagnostic radiology methods for assessing coronary artery bypass graft viability

The review describes available modern radiological methods which are currently applied for a detailed and comprehensive anatomical and functional assessment of the viability of various coronary artery bypass grafts. In addition, it presents some aspects of the implementation of these methods and clinical interpretation of the results.

Comparison of Machine Learning Models Including Preoperative, Intraoperative, and Postoperative Data and Mortality After Cardiac Surgery

IMPORTANCE

A variety of perioperative risk factors are associated with postoperative mortality risk. However, the relative contribution of routinely collected intraoperative clinical parameters to short-term and long-term mortality remains understudied.

OBJECTIVE

To examine the performance of multiple machine learning models with data from different perioperative periods to predict 30-day, 1-year, and 5-year mortality and investigate factors that contribute to these predictions.

DESIGN, SETTING, AND PARTICIPANTS

In this prognostic study using prospectively collected data, risk prediction models were developed for short-term and long-term mortality after cardiac surgery. Included participants were adult patients undergoing a first-time valve operation, coronary artery bypass grafting, or a combination of both between 1997 and 2017 in a single center, the University Medical Centre Groningen in the Netherlands. Mortality data were obtained in November 2017. Data analysis took place between February 2020 and August 2021.

EXPOSURE

Cardiac surgery.

MAIN OUTCOMES AND MEASURES

Postoperative mortality rates at 30 days, 1 year, and 5 years were the primary outcomes. The area under the receiver operating characteristic curve (AUROC) was used to assess discrimination. The contribution of all preoperative, intraoperative hemodynamic and temperature, and postoperative factors to mortality was investigated using Shapley additive explanations (SHAP) values.

RESULTS

Data from 9415 patients who underwent cardiac surgery (median [IQR] age, 68 [60-74] years; 2554 [27.1%] women) were included. Overall mortality rates at 30 days, 1 year, and 5 years were 268 patients (2.8%), 420 patients (4.5%), and 612 patients (6.5%), respectively. Models including preoperative, intraoperative, and postoperative data achieved AUROC values of 0.82 (95% CI, 0.78-0.86), 0.81 (95% CI, 0.77-0.85), and 0.80 (95% CI, 0.75-0.84) for 30-day, 1-year, and 5-year mortality, respectively. Models including only postoperative data performed similarly (30 days: 0.78 [95% CI, 0.73-0.82]; 1 year: 0.79 [95% CI, 0.74-0.83]; 5 years: 0.77 [95% CI, 0.73-0.82]). However, models based on all perioperative data provided less clinically usable predictions, with lower detection rates; for example, postoperative models identified a high-risk group with a 2.8-fold increase in risk for 5-year mortality (4.1 [95% CI, 3.3-5.1]) vs an increase of 11.3 (95% CI, 6.8-18.7) for the high-risk group identified by the full perioperative model. Postoperative markers associated with metabolic dysfunction and decreased kidney function were the main factors contributing to mortality risk.

CONCLUSIONS AND RELEVANCE

This study found that the addition of continuous intraoperative hemodynamic and temperature data to postoperative data was not associated with improved machine learning-based identification of patients at increased risk of short-term and long-term mortality after cardiac operations.

Robotic Coronary Revascularization is Feasible and Safe: 10-year Single-Center Experience

Objective

The purpose of this study is to investigate the outcomes of patients undergoing robotic surgical coronary revascularization whether total endoscopic coronary artery bypass (TECAB) or robotic-assisted minimally invasive direct coronary artery bypass (RA-MIDCAB) in our center.

Methods

This is a retrospective single-center study. It was conducted in the heart hospital at Hamad Medical Corporation, Qatar. We retrospectively studied all cases that had single grafts, left internal mammary artery (LIMA) to left anterior descending (LAD) coronary artery through a minimally invasive approach, either TECAB grafting or RA-MIDCAB grafting operations between February 2009 and December 2020. Both procedures were performed with the assistance of the da Vinci robotic system. In TECAB, the robotic system was used to harvest LIMA and perform the anastomosis with LAD. Whereas in RA-MIDCAB, LIMA was harvested by the robotic system but the anastomosis of LIMA to LAD was performed under direct vision through a small anterior thoracotomy incision. Seventy-one patients' files from the medical records department were reviewed. Preoperative data included age, gender, ethnicity, body mass index (BMI), cardiac risk factors, Euro score, presentation, and the results of the cardiac investigations. The intraoperative data were the type of procedure, operative time, and whether the procedure was completed as planned or converted to thoracotomy or sternotomy. The postoperative data included the length of hospital stay, postoperative complications, 3-month clinic follow-up, and the need for repeat coronary angiography or revascularization.

Results

We found that our patients' ages ranged from 31 to 70 years. The majority were males, with 64 (90.14%) patients. Thirty-one (44.93%) patients were found to have a BMI of 25-29.9 Kg/m2. Forty-seven (66.2%) patients were hypertensive and 37 (52.11%) were diabetic. Dyslipidemia was reported in 35 (50%) patients. TECAB was the primary procedure in 47 (66.2%) patients and the rest underwent RA-MIDCAB. Only 7 (10.14%) patients underwent a planned hybrid procedure. The procedure was completed as planned in 52 (73.2%) patients. The mean operative time was 355.9 ± 95.79 min. Fourteen (19.72%) TECAB procedures were converted to MIDCAB, whereas 5 (7.04%) required sternotomy. Thirteen (18.3%) patients were extubated on the table, 47 (66%) patients were extubated in <24 h, and 7 (9.8%) patients were extubated after 24 h of the procedure. Forty-two (59%) patients stayed only 24 h in ICU and 24 (33.8%) spent more than 24 h. Blood transfusion was required in 8 (11.2%) patients. Only 2 (2.8%) patients experienced bleeding after the surgery. Postoperative infection was observed in 3 (4.29%) patients. No new cerebrovascular accident was detected among the patients after the procedure. Median postoperative hospital stay was 5 days, interquartile range 2, range (2-39). During the 3-month postoperative follow-up, we found that three unplanned coronary angiographies were required for repeat intervention, one of them for LIMA-LAD anastomosis. No redo surgery was performed. Thirty-day mortality was reported in two patients only.

Conclusion

From our experience over more than 10 years in robotic cardiac surgery in Qatar, we believe that robotic coronary revascularization is safe and feasible in selected patients mainly with single vessel coronary artery disease but should be performed in specialized centers and by robotic-trained surgeons.

Clinical event rate in patients with and without left main disease undergoing isolated CABG: results from the European DuraGraft registry

OBJECTIVES

Left main coronary artery disease (LMCAD) is considered an independent risk factor for clinical events after coronary artery bypass grafting (CABG). We have conducted a subgroup analysis of the multicentre European DuraGraft registry to investigate clinical event-rates at 1-year in patients with and without LMCAD undergoing isolated CABG in contemporary practice.

METHODS

Patients undergoing isolated CABG were selected. The primary end-point was the incidence of a major adverse cardiac event (MACE) defined as the composite of death, myocardial infarction (MI) or repeat revascularization (RR) at 1-year. The secondary end-point was major adverse cardiac and cerebrovascular events (MACCE) defined as MACE plus stroke. Propensity score matching (PSM) was performed to balance for differences in baseline characteristics.

RESULTS

LMCAD was present in 1,033 (41.2%) and absent in 1,477 (58.8%) patients. At 1-year, the MACE rate was higher for LMCAD patients (8.2% vs 5.1%, p = 0.002) driven by higher rates of death (5.4% vs 3.4%, p = 0.016), MI (3.0% vs 1.3%, p = 0.002) and numerically higher rates of RR (2.8% vs 1.8%, p = 0.13). The incidence of MACCE was 8.8% vs 6.6%, p = 0.043 with a stroke rate of 1.0% and 2.4%, p = 0.011, for LMCAD and non-LMCAD group, respectively. After PSM, the MACE rate was 8.0% vs 5.2%, p = 0.015. The incidence of death was 5.1% vs 3.7%, p = 0.10, MI 3.0% vs 1.4%, p = 0.020, and RR was 2.7% vs 1.6%, p = 0.090, for the LMCAD and non-LMCAD group, respectively. Less strokes occurred in LMCAD patients (1.0% vs 2.4%, p = 0.017). The MACCE rate was not different: 8.5% vs 6.7%, p = 0.12.

CONCLUSIONS

In this large registry, LMCAD was demonstrated to be an independent risk factor for MACE after isolated CABG. Conversely, the risk of stroke was lower in LMCAD patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02922088.

Impaired fibrin clot lysis is associated with increased mortality in patients after coronary artery bypass grafting: A long-term follow-up study

BACKGROUND

Mortality after coronary artery bypass grafting (CABG) is primarily thromboembolic by nature. We investigated whether impaired fibrinolysis observed in cardiovascular diseases is associated with long-term mortality following CABG.

METHODS

The study population comprised 292 consecutive patients (aged 64.6 ± 8.1 years) who underwent scheduled CABG. We measured plasma clot lysis time (CLT) preoperatively as a measure of fibrinolysis capacity. Cardiovascular and all-cause deaths were recorded during a median follow-up of 13.8 years.

RESULT

CLT positively correlated with age (r = .56, p < .001), fibrinogen (r = .25, p = .002) and EuroSCORE I (r = .32, p < .001). The cardiovascular and overall mortality rates were 3.0 and 4.9 per 100 patient-years (32.4% vs 52.8%) respectively. In patients who died from cardiovascular and all causes, CLT was prolonged compared with survivors (both p < .050). Multivariable Cox regression analysis adjusted for potential confounders showed that long-term cardiovascular and all-cause deaths were associated with CLT (HR per 10 min 1.206; 95% CI 1.037-1.402, p = .015 and HR 1.164; 96% CI 1.032-1.309, p = .012), low-density lipoprotein cholesterol (HR per 1 mmol/L 1.556; 95% CI 1.205-2.010, p < .001 and HR 1.388; 96% CI 1.125-1.703, p = .002), C-reactive protein (HR per 10 mg/L 1.171; 95% CI 1.046-1.312, p = .006 and HR 1.127; 95% CI 1.005-1.237, p = .022) and EuroSCORE I (HR 1.173; 95% CI 1.016-1.355, p = .030 and HR 1.183; 95% CI 1.059-1.317, p = .003 respectively). Type 2 diabetes was solely associated with overall mortality (HR 1.594; 96% CI 1.088-2.334, p = .017).

CONCLUSIONS

In this study, we showed that reduced fibrin clot susceptibility to fibrinolysis is weekly associated with long-term mortality in advanced CAD.

Comparison of Coronary Artery Bypass Grafting and Drug-Eluting Stent Implantation in Patients With Chronic Kidney Disease: A Propensity Score Matching Study

Objectives

To compare the long-term outcomes of coronary artery bypass grafting (CABG) vs. percutaneous coronary intervention (PCI) with drug-eluting stents (DESs) for coronary artery disease (CAD) patients with chronic kidney disease (CKD).

Methods

Coronary artery disease patients with decreased kidney function (estimated glomerular filtration rate &lt;60 ml/min/1.73 m2) who underwent CABG (n = 533) or PCI with DES (n = 952) from 2013 to 2020 were enrolled at a single center. The baseline characteristics and clinical outcomes were compared between the CABG and PCI groups for each matched pair of patients with CKD. The primary endpoint was the occurrence of all-cause death. The secondary endpoints were major adverse cardiovascular events (MACCEs) such as death, myocardial infarction (MI), stroke, and repeat revascularization.

Results

A total of 1,485 patients underwent revascularization, such as 533 CABG and 952 patients with PCI. The median follow-up duration was 55.6 months (interquartile range 34.3–74.7 months). Multivariable Cox regression models were used for risk adjustment, and after propensity score matching (PSM), 399 patients were well matched in each group. The in-hospital mortality rate in the CABG group was higher than that in the PCI group, but the difference was not statistically significant (5.0 vs. 2.5%, p = 0.063). At the 1-year follow-up, CABG was associated with a lower survival rate than PCI (94.2 vs. 98.0%, hazard ratio [HR] of 3.72, 95% CI = 1.63–8.49, p &lt; 0.01). At the end of the 5-year follow-up, the freedom from MI and the freedom from repeated revascularization were both better in the CABG group compared to the PCI group (89.1 vs. 81.7%, HR of 0.59, 95% CI = 0.38–0.92, p = 0.019; 86.9 vs. 73.8%, HR of 0.54, 95% CI = 0.36–0.81, p = 0.003, respectively). Furthermore, the freedom from MACCEs was also better in the patients of CABG compared with the patients of PCI (58.5 vs. 51.3%, HR of 0.71, 95% CI = 0.55–0.91, p = 0.030). CABG had a higher cumulative survival rate (68.4 vs. 66.0%) but without a statistically significant difference (HR of 0.92, 95% CI = 0.67–1.27, p = 0.602) compared with that of PCI.

Conclusions

Compared to the use of PCI with a drug-eluting stent among patients with CKD, the use of CABG was associated with a lower MI rate, repeat revascularization rate, and lower number of MACCEs during the long-term follow-up. At a follow-up of 1 year, the number of MACCEs and other adverse events were comparable between the two cohorts, but CABG showed a lower survival rate than PCI.

A novel nomogram for predicting 3-year mortality in critically ill patients after coronary artery bypass grafting

Background

The long-term outcomes for patients after coronary artery bypass grafting (CABG) have been received more and more concern. The existing prediction models are mostly focused on in-hospital operative mortality after CABG, but there is still little research on long-term mortality prediction model for patients after CABG.

Objective

To develop and validate a novel nomogram for predicting 3-year mortality in critically ill patients after CABG.

Methods

Data for developing novel predictive model were extracted from Medical Information Mart for Intensive cart III (MIMIC-III), of which 2929 critically ill patients who underwent CABG at the first admission were enrolled.

Results

A novel prognostic nomogram for 3-year mortality was constructed with the seven independent prognostic factors, including age, congestive heart failure, white blood cell, creatinine, SpO₂, anion gap, and continuous renal replacement treatment derived from the multivariable logistic regression. The nomogram indicated accurate discrimination in primary (AUC: 0.81) and validation cohort (AUC: 0.802), which were better than traditional severity scores. And good consistency between the predictive and observed outcome was showed by the calibration curve for 3-year mortality. The decision curve analysis also showed higher clinical net benefit than traditional severity scores.

Conclusion

The novel nomogram had well performance to predict 3-year mortality in critically ill patients after CABG. The prediction model provided valuable information for treatment strategy and postdischarge management, which may be helpful in improving the long-term prognosis in critically ill patients after CABG.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12893-021-01408-8.

Association Between Postoperative Thrombocytopenia and Outcomes After Coronary Artery Bypass Grafting Surgery

Objectives: The effect of postoperative thrombocytopenia on adverse events among coronary artery bypass graft (CABG) patients remains unclear. This study aims to investigate the association between postoperative thrombocytopenia and perioperative outcomes of CABG. Methods: This is a retrospective study with MIMIC-III (Medical Information Mart for Intensive Care III) database. Adult patients who underwent CABG were included to analyze the impact of thrombocytopenia in patients' outcomes. Postoperative thrombocytopenia was defined as a platelet count <100 × 10⁹/L on the first day after CABG surgery. A multivariable logistic regression analysis was utilized to adjust the effect of thrombocytopenia on outcomes for baseline and covariates, and to determine the association with outcomes. Results: A total of 4,915 patients were included, and postoperative thrombocytopenia occurred in 696 (14.2%) patients. Postoperative thrombocytopenia was not associated with increased 28-day mortality (OR 0.75; 95% CI 0.33-1.72; P = 0.496) or in-hospital mortality (OR 0.75; 95% CI 0.34-1.63; P = 0.463) after adjusting for confounders. Regarding the secondary outcomes, it was associated with a higher risk of a prolonged stay in the intensive care unit (OR 1.53; 95% CI 1.18-1.97; P = 0.001), prolonged hospital stays (OR 1.58; 95% CI 1.21-2.06; P = 0.001), prolonged mechanical ventilation time (OR 1.67; 95% CI 1.14-2.44; P = 0.009), and a trend toward increased occurrence of massive bleeding (OR 1.41; 95% CI 1.00-2.01; P = 0.054). There was no significant association between an increased risk of prolonged vasopressor use and the continuous renal replacement therapy rate. Conclusions: Postoperative thrombocytopenia was associated with prolonged ICU and hospital stays but not with increased perioperative mortality among CABG patients.

Long-Term Survival After On-Pump and Off-Pump Coronary Artery Bypass Grafting

BACKGROUND

Off-pump coronary artery bypass grafting (CABG) may be associated with increased hazard for long-term mortality as compared to on-pump CABG. We sought to evaluate risk-adjusted long-term survival after off-pump and on-pump CABG, particularly among high-volume and low-volume CABG surgeons.

METHODS

We evaluated 1,235,089 isolated CABGs (off-pump = 209,085; on-pump = 1,026,004) performed in Medicare beneficiaries from 2001-2015. Long-term hazard for mortality after off-pump versus on-pump CABG was compared with Kaplan-Meier and log-rank analysis among all CABG surgeons as well as high-volume and low-volume CABG surgeons, before and after inverse-probability of treatment weighting (IPTW) to adjust for confounding.

RESULTS

Among all surgeons, off-pump CABG was associated with a statistically-significant hazard for mortality as compared to on-pump CABG before and after IPTW (median survival: off-pump 9.8 years vs on-pump 10.2 years; difference in median survival -134 days; log-rank p<0.001). Cox regression analysis confirmed an interaction between surgeon volume and long-term mortality. The hazard for mortality associated with off-pump CABG was decreased among high-volume surgeons (difference in median survival: -84 days; log-rank p<0.001) and increased among low-volume surgeons (difference in median survival: -240 days; long-rank p<0.001).

CONCLUSIONS

Off-pump CABG was associated with a significant, but clinically modest, increased hazard for mortality as compared to on-pump CABG. The hazard was reduced when off-pump CABG was performed by high-volume CABG surgeons.

Determinants of the Downward Trend in Coronary Artery Bypass Graft Surgery Among Patients With Multivessel Disease and Class-I Indication for Surgery

Introduction

Coronary artery bypass graft (CABG) is the most effective coronary revascularization procedure, and it has been endorsed by many trials and studies over the years. However, due to CABG's immediate adverse effects, patients tend to prefer percutaneous coronary intervention (PCI) for coronary revascularization over it. This article focuses on the recent downtrend in CABG procedures for revascularization among patients for whom it is indicated. This study’s main objective was to identify the factors responsible for the downtrend in patients undergoing CABG despite a clear indication for it in those with multivessel diseases.

Methods

This study was conducted at the Lady Reading Hospital, Peshawar, Pakistan, from August 1, 2020, to January 1, 2021. A total of 340 patients with a class-I indication (presence of conditions regarding which there is evidence and/or general agreement that a given procedure or treatment is beneficial, useful, and effective) for CABG were enrolled in the study. Data related to all the variables were collected from patients and hospital records through an adequately designed proforma. For analysis, we applied the chi-square test to elaborate on the data for information and point biserial correlation to rule out the effect of age and weight on CABG’s downward trend.

Results

The mean age of the patients was 58.77 ± 9.54 years; 65.88% were male, and 34.12% were female. Only 17.65% of the patients underwent CABG; 71.47% opted for medical treatment, and 9.41% underwent PCI. Out of the 280 patients who did not undergo CABG, 26.76% had financial issues; 23.82% were high-risk patients and hence refused surgeries by the surgeons; 20.59% of patients were not willing to undergo surgery; 7.94% were on the waiting list, and 3.24% had deranged renal function tests (RFTs).

Conclusions

A limited number of patients underwent revascularization therapy even though they had clear indications for CABG. The high-risk status of patients, patients' unwillingness, and the cost of the procedure were the primary reasons behind the downtrend in CABG procedures among patients with a clear indication for the same.

Impact of postoperative complications after cardiac surgery on long-term survival

PURPOSE

The impact of postoperative complications on long-term survival is not well characterized. We sought to study the prevalence of postoperative complications after cardiac surgery and their impact on long-term survival.

METHODS

Operative survivors (n = 26,221) who underwent coronary artery bypass grafting (CABG) (n = 13,054, 49.8%), valve surgery (n = 8667, 33.1%) or combined CABG and valve surgery (n = 4500, 17.2%) from 1993 to 2019 were included in the study. Records were reviewed for postoperative complications and long-term survival. Propensity-match analysis was performed between patients who did and did not have a postoperative complication. The associations between postoperative complications and survival were assessed using a Cox-proportional model.

RESULTS

Complications occurred in 17,463 (66.6%) of 26,221 operative survivors. A total of 17 postoperative complications were analyzed. Postoperative blood product use was the commonest (n = 12,397, 47.3%), followed by atrial fibrillation (n = 8399, 32.0%), prolonged ventilation (n = 2336, 8.9%), renal failure (n = 870, 3.3%), reoperation for bleeding (n = 859, 3.3%) and pacemaker/ICD insertion (n = 795, 3.0%). Stroke (hazard ratio [HR]: 1.55; 95% confidence interval [CI]: 1.36-1.77), renal failure (HR: 1.45; 95% CI: 1.33-1.58) and pneumonia (HR: 1.23; 95% CI: 1.11-1.36) had the strongest impact on long-term survival. Long-term survival decreased as the number of postoperative complications increased.

CONCLUSIONS

Postoperative complications after cardiac surgery significantly impact outcomes that extend beyond the postoperative period. Stroke, renal failure, and pneumonia are particularly associated with poor long-term survival.

Monitoring the Impact of Aggressive Glycemic Intervention during Critical Care after Cardiac Surgery with a Glycemic Expert System for Nurse-Implemented Euglycemia: The MAGIC GENIE Project

A novel, multi-dimensional protocol named GENIE has been in use for intensive insulin therapy (IIT, target glucose <140 mg/dL) in the surgical intensive care unit (SICU) after open heart surgery (OHS) at VA Pittsburgh since 2005. Despite concerns over increased mortality from IIT after the publication of the NICE-SUGAR Trial, it remains in use, with ongoing monitoring under the MAGIC GENIE Project showing that GENIE performance over 12 years (2005-2016) aligns with the current consensus that IIT with target blood glucose (BG) <140 mg/dL is advisable only if it does not provoke severe hypoglycemia (SH). Two studies have been conducted to monitor glucometrics and outcomes during GENIE use in the SICU. One compares GENIE (n = 382) with a traditional IIT protocol (FORMULA, n = 289) during four years of contemporaneous use (2005-2008). The other compares GENIE's impact overall (n = 1404) with a cohort of patients who maintained euglycemia after OHS (euglycemic no-insulin [ENo-I], n = 111) extending across 12 years (2005-2016). GENIE performed significantly better than FORMULA during contemporaneous use, maintaining lower time-averaged glucose, provoking less frequent, severe, prolonged, or repetitive hypoglycemia, and achieving 50% lower one-year mortality, with no deaths from mediastinitis (0 of 8 cases vs 4 of 9 on FORMULA). Those benefits were sustained over the subsequent eight years of exclusive use in OHS patients, with an overall one-year mortality rate (4.2%) equivalent to the ENo-I cohort (4.5%). The results of the MAGIC GENIE Project show that GENIE can maintain tight glycemic control without provoking SH in patients undergoing OHS, and may be associated with a durable survival benefit. The results, however, await confirmation in a randomized control trial.

Utility of nuclear stress imaging in predicting long-term outcomes one-year post CABG Surgery

BACKGROUND

Early MPI after CABG is currently considered rarely appropriate in asymptomatic patients. This study aimed to identify prognostic value of nuclear stress-imaging post-CABG.

METHODS

This was a single center prospective study looking at long-term outcomes post-CABG. Per protocol participants underwent SPECT-MPI stress testing and coronary angiogram on the same day, 1-year following CABG. Defect size was semi-quantified. The primary outcomes were the composite of death and congestive heart failure.

RESULTS

Eighty-four participants underwent nuclear stress-imaging and angiography, with a median follow-up of 11.1 years. Three separate stress findings predicted the primary outcome: inability to reach stage 3 of a Bruce protocol (OR 7.3, CI 2.4-22.1, P < 0.001), LVEF < 45% (OR 4.0, CI 1.1-15.3, P = 0.041) and a moderate-large stress defect size (HR 2.31, CI 1.1-1.5, P = 0.04). These findings appear to be additive and strongest among patients who underwent exercise stress testing (HR 10.6, CI 3.6-30.6, P < 0.001). Graft disease was identified in 39 (46%) patients and compared to those individuals with no graft disease, did not predict long-term adverse outcomes (P = 0.29).

CONCLUSION

In clinically stable patients early after revascularization with CABG, SPECT-MPI can identify patients at higher risk of heart failure and death.

Predictors of Hospital Readmission within 30 Days after Coronary Artery Bypass Grafting: Data Analysis of 2,272 Brazilian Patients

Introduction

In order to reduce readmission rates after coronary artery bypass grafting (CABG), its predictors should be known in different contexts. The objective of this study was to identify predictive factors of hospital readmission within 30 days after CABG in a Brazilian center.

Methods

A secondary analysis of an electronic database of patients submitted to isolated CABG was performed. The relationship between readmission within 30 days and demographic, anthropometric, clinical, and surgery-related characteristics was investigated by univariate analyses. Predictors were identified by multiple logistic regression.

Results

Data from 2,272 patients were included, with an incidence of readmission of 8.6%. The predictors of readmission were brown skin color (Beta=1.613; 95% confidence interval [CI] 1.047-2.458; P=0.030), African-American ethnicity (Beta=0.136; 95% CI 0.019-0.988; P=0.049), chronic kidney disease (Beta=2.214; 95% CI 1.269-3.865; P=0.005), postoperative use of blood products (Beta=1.515; 95% CI 1.101-2.086; P=0.011), chronic obstructive pulmonary disease (Beta=2.095; 95% CI 1.284-3.419; P=0.003), and use of acetylsalicylic acid (Beta=1.418; 95% CI 1.000-2.011; P=0.05). Preoperative antibiotic prophylaxis (Beta=0.742; 95% CI 0.5471.007; P=0.055) was marginally significant.

Conclusion

The predictors identified may support a closer postoperative follow-up and individualized planning for a safe discharge.

Medical therapy vs early revascularization in diabetics with chronic total occlusions: A meta-analysis and systematic review

BACKGROUND

Management of chronic total occlusions (CTO) in diabetics is challenging, with a recent trend towards early revascularization [ER: Percutaneous coronary intervention (PCI) and bypass grafting] instead of optimal medical therapy (OMT). We hypothesize that ER improves morbidity and mortality outcomes in diabetic patients with CTOs as compared to OMT.

AIM

To determine the long term clinical outcomes and to compare morbidity and mortality between OMT and ER in diabetic patients with CTOs.

METHODS

Potentially relevant published clinical trials were identified in Medline, Embase, chemical abstracts and Biosis (from start of the databases till date) and pooled hazard ratios (HR) computed using a random effects model, with significant P value < 0.05. Primary outcome of interest was all-cause death. Secondary outcomes included cardiac death, prompt revascularization (ER) or repeat myocardial infarction (MI). Due to scarcity of data, both Randomized control trials and observational studies were included. 4 eligible articles, containing 2248 patients were identified (1252 in OMT and 1196 in ER). Mean follow-up was 45-60 mo.

RESULTS

OMT was associated with a higher all-cause mortality [HR: 1.70, 95% confidence interval (CI): 0.80-3.26, P = 0.11] and cardiac mortality (HR: 1.68, 95%CI: 0.96-2.96, P = 0.07). Results were close to significance. The risk of repeat MI was almost the same in both groups (HR: 0.97, 95%CI: 0.61-1.54, P = 0.90). Similarly, patients assigned to OMT had a higher risk of repeat revascularization (HR: 1.62, 95%CI: 1.36-1.94, P < 0.00001). Sub-group analysis of OMT vs PCI demonstrated higher all-cause (HR: 1.98, 95%CI: 1.36-2.87, P = 0.0003) and cardiac mortality (HR: 1.87, 95%CI: 0.96-3.62, P = 0.06) in the OMT group. The risk of repeat MI was low in the OMT group vs PCI (HR: 0.53, 95%CI: 0.31-0.91, P = 0.02). Data on repeat revascularization revealed no difference between the two (HR: 1.00, 95%CI: 0.52-1.93, P = 1.00).

CONCLUSION

In diabetic patients with CTO, there was a trend for improved outcomes with ER regarding all-cause and cardiac death as compared to OMT. These findings were reinforced with statistical significance on subgroup analysis of OMT vs PCI.

Noninvasive flow evaluations of coronary artery bypass grafting using dynamic cardiac CT

We aimed to investigate the correlation of graft flow measurements between transit-time flow measurement (TTFM) during coronary artery bypass grafting (CABG) surgery and dynamic cardiac CT after the surgery.Fourteen patients underwent CABG with TTFM and postoperative dynamic cardiac CT; 11 internal thoracic artery (ITA) grafts and 15 saphenous venous grafts (SVGs) were included for analysis. Pearsons correlation analysis was performed for the comparisons of the TTFM and cardiac dynamic CT flow parameters.TTFM was not significantly correlated with the CT flow of the ITA grafts (r = -0.23, P = .49), but it had a very strong correlation with the CT flow of the SVGs (r = 0.83, P < .01).In patients who underwent CABG surgery, dynamic cardiac CT enabled quantitative evaluation of SVG flow, with good correlation with TTFM.

The trade-off between costs and outcome after cardiac surgery. Evidence from an Italian administrative registry

Effective resource allocation policies relating to the long-term effects of complex surgical procedures require accurate prediction of the likelihood of future hospitalization. By approximating clinical conditions with administrative data and controlling for complex case-mix scenarios, we provide evidence of a trade-off between costs and outcome in cardiac surgery. We modelled administrative data to account for clinical conditions in a population of patients admitted for cardiac surgery and their readmissions for complications. Costs were calculated at first admission, the outcome variable was defined as time to readmission within six months post-discharge. Risk factors for readmission were defined as comorbidities and postoperative complications, derived by clinical judgement from the International Classification of Diseases. We predicted health outcome as a function of costs and other patient- and hospital-level features using a two-stage residual inclusion estimation method to tackle endogenous relationships applied to Cox proportional hazard models. We confirmed the trade-off and negative association between costs and hazard of readmission when controlling for all complex risk factors. Accurate matching of standard codes for diseases and procedures with clinical conditions may be a reliable methodology to assess time to readmissions and costs on a large population scale.

Adverse Outcomes Associated With Delaying or Withholding β-Blockers After Cardiac Surgery: A Retrospective Single-Center Cohort Study

BACKGROUND

Ideal timing of postoperative β-blockers is unclear. We hypothesized that patients who do not receive β-blockers immediately after cardiac surgery would have increased in-hospital mortality (primary outcome) and postoperative hemodynamic, pulmonary, neurologic, or respiratory complications (secondary outcomes).

METHODS

We performed a retrospective cohort study evaluating patients who underwent cardiac surgery at our institution from January 1, 2013 to September 30, 2017. We compared outcomes between patients who received β-blockers by postoperative day (POD) 5 with outcomes in patients who did not receive β-blockers at any time or received them after POD 5. Inverse probability of treatment weighting was used to minimize confounding. Univariate logistic regression analyses were performed on the weighted sets using absent or delayed β-blockers as the independent variable and each outcome as dependent variables in separate analyses. A secondary analysis was performed in patients prescribed preoperative β-blockers. E-values were calculated for significant outcomes.

RESULTS

All results were confounder adjusted. Among patients presenting for cardiac surgery, not receiving β-blockers by POD 5 or at any time was not associated with the primary outcome in-hospital mortality, estimated odds ratio (OR; 99.5% confidence interval [CI]) of 1.6 (0.49-5.1), P = .28. Not receiving β-blockers by POD 5 or at any time was associated with postoperative atrial fibrillation, estimated OR (99.5% CI) of 1.5 (1.1-2.1), P < .001, and pulmonary complications, estimated OR (99.5% CI) of 3.0 (1.8-5.2), P < .001. E-values were 2.4 for postoperative atrial fibrillation and 5.6 for pulmonary complications. Among patients presenting for cardiac surgery taking preoperative β-blockers, not receiving β-blockers by POD 5 or at any time was not associated with the primary outcome mortality, with estimated OR (99.5% CI) of 1.3 (0.43-4.1), P = .63. In this subset, not receiving β-blockers by POD 5 or at any time was associated with increased adjusted ORs of postoperative atrial fibrillation (OR = 1.6; 99.5% CI, 1.1-2.4; P < .001) and postoperative pulmonary complications (OR = 2.8; 99.5% CI, 1.6-5.2; P < .001). Here, e-values were 2.7 for postoperative atrial fibrillation and 5.1 for pulmonary complications. For the sensitivity analyses for secondary outcomes, exposure and outcome periods overlap. Outcomes may have occurred before or after postoperative β-blocker administration.

CONCLUSIONS

Among patients who undergo cardiac surgery, not receiving postoperative β-blockers within the first 5 days after cardiac surgery or at any time is not associated with in-hospital mortality and is associated with, but may not necessarily cause, postoperative atrial fibrillation and pulmonary complications.

The use of both internal thoracic arteries for coronary revascularization increases the estimate of post-operative lower limb ischemia in patients with peripheral artery disease

Background

Patients with a history of peripheral arterial disease (PAD) undergoing coronary artery bypass grafting (CABG) exhibit higher rates of complications. There are conflicting data on the survival benefits for bilateral thoracic artery (BITA) grafting compared with left internal thoracic artery (LITA) CABG in patients with PAD. The aim of the study was to explore the influence of the use of BITA grafts vs. LITA for CABG on post-operative acute lower limb ischemia (ALLI) and main post-operative complications in patients with concomitant PAD.

Methods

We used a propensity-score (PS) based analysis to compare outcomes between the two surgical procedures, BITA and LITA. The inverse probability of treatment weighting PS technique was applied to adjust for pre- and intra-operative confounders, and to get optimal balancing of the pre-operative data. The primary outcome was the estimate of postoperative ALLI. Secondary outcomes included overall death and death of cardiac causes within 30 days of surgery, stroke and acute kidney disease (AKD).

Results

The study population consisted of 1961 patients. The LITA procedure was performed in 1768 patients whereas 193 patients underwent a BITA technique. The estimate of ALLI was 14% higher in the BITA compared to the LITA (p < 0.001) group. Thirty-day mortality, cardiac death, occurrence of stroke and AKI did not differ significantly between the groups.

Conclusions

The use of both ITAs led to a significant increase in ALLI. This result was most likely caused by the complete disruption of the ITA collateral providing additional blood supply to the lower extremities. Based on our data, BITA should be used with extreme caution in PAD patients. Further research on this topic is necessary to confirm our findings.

Effects of Preoperative WBC Count on Post-CABG Surgery Clinical Outcome

OBJECTIVE

White blood cells (WBCs) play a major role in inflammation, with effects on the vascular wall, the microvascular blood flow, and endothelial cells and endothelial function. Previous studies have shown that a high WBC count may increase the risk of cardiovascular complication rate and mortality after coronary artery bypass graft (CABG) surgery. The aim of the study was to evaluate the association between preoperative WBC count and the post-CABG clinical outcome.

METHODS

A retrospective study that was based on 239 patients who underwent CABG surgery in our medical center. Statistical analysis estimated the effect of WBC count in postoperative clinical outcomes, including atrial fibrillation, length of stay, readmission rate, and death.

RESULTS

The preoperative WBC count was associated with longer hospitalization length (B = 0.392, P < 0.01). A preoperative WBC count >8150/μL predicted a longer stay (Z = 2.090, P = 0.03). A low lymphocyte count was associated with atrial fibrillation (B = -0.543, P = 0.03). Female patients were older (Z = 2.920, P < 0.01), had impaired renal function (Z = -3.340, P < 0.01), and had a higher rate of postoperative atrial fibrillation (df 2 = 3.780, P = 0.05) and readmission (df 2 = 5.320, P = 0.02).

CONCLUSIONS

Preoperative WBC count may have an effect on the postoperative clinical outcome in patients undergoing CABG. Surgeons should pay more attention to patients' WBC count and sex and plan surgery and postoperative management accordingly.

Association of Functional, Cognitive, and Psychological Measures With 1-Year Mortality in Patients Undergoing Major Surgery

Importance

More older adults are undergoing major surgery despite the greater risk of postoperative mortality. Although measures, such as functional, cognitive, and psychological status, are known to be crucial components of health in older persons, they are not often used in assessing the risk of adverse postoperative outcomes in older adults.

Objective

To determine the association between measures of physical, cognitive, and psychological function and 1-year mortality in older adults after major surgery.

Design, Setting, and Participants

Retrospective analysis of a prospective cohort study of participants 66 years or older who were enrolled in the nationally representative Health and Retirement Study and underwent 1 of 3 types of major surgery.

Exposures

Major surgery, including abdominal aortic aneurysm repair, coronary artery bypass graft, and colectomy.

Main Outcomes and Measures

Our outcome was mortality within 1 year of major surgery. Our primary associated factors included functional, cognitive, and psychological factors: dependence in activities of daily living (ADL), dependence in instrumental ADL, inability to walk several blocks, cognitive status, and presence of depression. We adjusted for other demographic and clinical predictors.

Results

Of 1341 participants, the mean (SD) participant age was 76 (6) years, 737 (55%) were women, 99 (7%) underwent abdominal aortic aneurysm repair, 686 (51%) coronary artery bypass graft, and 556 (42%) colectomy; 223 (17%) died within 1 year of their operation. After adjusting for age, comorbidity burden, surgical type, sex, race/ethnicity, wealth, income, and education, the following measures were significantly associated with 1-year mortality: more than 1 ADL dependence (29% vs 13%; adjusted hazard ratio [aHR], 2.76; P = .001), more than 1 instrumental ADL dependence (21% vs 14%; aHR, 1.32; P = .05), the inability to walk several blocks (17% vs 11%; aHR, 1.64; P = .01), dementia (21% vs 12%; aHR, 1.91; P = .03), and depression (19% vs 12%; aHR, 1.72; P = .01). The risk of 1-year mortality increased within the increasing risk factors present (0 factors: 10.0%; 1 factor: 16.2%; 2 factors: 27.8%).

Conclusions and Relevance

In this older adult cohort, 223 participants (17%) who underwent major surgery died within 1 year and poor function, cognition, and psychological well-being were significantly associated with mortality. Measures in function, cognition, and psychological well-being need to be incorporated into the preoperative assessment to enhance surgical decision-making and patient counseling.

Ablation of atrial fibrillation during coronary artery bypass grafting: Late outcomes in a Medicare population

BACKGROUND

This study compares outcomes of patients with preoperative atrial fibrillation undergoing coronary artery bypass grafting (CABG) with or without concomitant atrial fibrillation ablation in a nationally representative Medicare cohort.

OBJECTIVES

This study examined early and late outcomes in CABG patients with a preoperative history of atrial fibrillation to determine the correlation between surgical atrial fibrillation ablation to mortality and stroke or systemic embolization.

METHODS

In the Medicare-linked Society of Thoracic Surgeons database, 361,138 patients underwent isolated CABG from 2006 to 2013; 34,600 (9.6%) had preoperative atrial fibrillation; 10,541 (30.5%) were treated with surgical ablation (ablation group), and 23,059 were not (no ablation group). Propensity score matching was performed using a hierarchical mixed model. Long-term survival was summarized using Kaplan-Meier curves and Cox regression models with robust variance estimation. The stroke or systemic embolization incidence was modeled using the Fine-Gray model. Median follow-up was 4 years.

RESULTS

Long-term mortality in propensity score-matched CABG patients (mean age 74 years; Society of Thoracic Surgeons risk score, 2.25) receiving ablation versus no ablation was similar (log-rank P = .30). Stroke or systemic embolization occurred in 2.2% versus 2.1% at 30 days and 9.9% versus 12.0% at 5 years (Gray P = .0091). Landmark analysis from 2 to 5 years showed lower mortality (hazard ratio, 0.89; 95% confidence interval 0.82-0.97; P = .0358) and lower risk of stroke or systemic embolization (hazard ratio, 0.73; 95% confidence interval, 0.61-0.87; P = .0006) in the ablation group.

CONCLUSIONS

Concomitant ablation in CABG patients with preoperative atrial fibrillation is associated with lower stroke or systemic embolization and mortality in patients who survive more than 2 years.

Gait Speed and 1-Year Mortality Following Cardiac Surgery: A Landmark Analysis From the Society of Thoracic Surgeons Adult Cardiac Surgery Database

Background

In older adults undergoing cardiac surgery, prediction of downstream risk is critical. Our objective was to determine the association of 5‐m gait speed with 1‐year mortality and repeat hospitalization following cardiac surgery.

Methods and Results

In this prospective cohort of patients undergoing cardiac surgery at centers participating in the Society of Thoracic Surgeons Database with gait speed recorded, we examined all‐cause mortality using a landmark analysis at 0 to 30, 30 to 365, and >365 days, as well as repeat hospitalization. The cohort consisted of 8287 patients (median age, 74 years; 32% females). At 1 year, survival was 90% in the slow (<0.83 m/s), 95% in the middle (0.83–1.00 m/s), and 97% in the fast (>1.00 m/s) gait speed tertiles, and risk of hospitalization was 45%, 33%, and 27%, respectively (both P<0.0001). After adjustment, gait speed remained predictive of mortality (hazard ratio, 2.16 per 0.1‐m/s decrease in gait speed; 95% confidence interval, 1.59–2.93) and rehospitalization (hazard ratio, 1.71 per 0.1‐m/s decrease in gait speed; 95% confidence interval, 1.45–2.0). In a landmark analysis, the effect of slow gait speed on mortality was most marked from 30 to 365 days after surgery, where each decline in 0.1 m/s of gait speed conferred a 2‐fold increased risk of mortality.

Conclusions

Gait speed is a simple tool to screen for frailty and identify older adults at risk for adverse events in the early and midterm postoperative periods.

A simple-to-use nomogram to predict long term survival of patients undergoing coronary artery bypass grafting (CABG) using bilateral internal thoracic artery grafting technique

BACKGROUND

Several risk scores have been created to predict long term mortality after coronary artery bypass grafting (CABG). Several studies demonstrated a reduction in long-term mortality following bilateral internal thoracic arteries (BITA) compared to single internal thoracic artery. However, these prediction models usually referred to long term survival as survival of up to 5 years. Moreover, none of these models were built specifically for operation incorporating BITA grafting.

METHODS

A historical cohort study of all patients who underwent isolated BITA grafting between 1996 and 2011 at Tel-Aviv Sourasky medical center, a tertiary referral university affiliated medical center with a 24-bed cardio-thoracic surgery department. Study population (N = 2,935) was randomly divided into 2 groups: learning group which was used to build the prediction model and validation group. Cox regression was used to predict death using pre-procedural risk factors (demographic data, patient comorbidities, cardiac characteristics and patient's status). The accuracy (discrimination and calibration) of the prediction model was evaluated.

METHODS AND FINDINGS

The learning (1,468 patients) and validation (1,467 patients) groups had similar preoperative characteristics and similar survival. Older age, diabetes mellitus, chronic obstructive lung disease, congestive heart failure, chronic renal failure, old MI, ejection fraction ≤30%, pre-operative use of intra-aortic balloon, and peripheral vascular disease, were significant predictors of mortality and were used to build the prediction model. The area under the ROC curves for 5, 10, and 15-year survival ranged between 0.742 and 0.762 for the learning group and between 0.766 and 0.770 for the validation group. The prediction model showed good calibration performance in both groups. A nomogram was built in order to introduce a simple-to-use tool for prediction of 5, 10, and 15-year survival.

CONCLUSIONS

A simple-to-use validated model can be used for a prediction of 5, 10, and 15-year mortality after CABG using the BITA grafting technique.

Comparison Effect of Tranexamic Acid (TA) and Tranexamic Acid Combined with Vitamin C (TXC) on Drainage Volume and Atrial Fibrillation Arrhythmia in Patients Undergoing Cardiac Bypass Surgery: Randomized Clinical Trial

BACKGROUND

Tranexamic acid and vitamin C are potent antifibrinolytic and oxidative stress agents that reduce blood loss and transfusion blood in cardiopulmonary bypass (CPB).

OBJECTIVES

The aim of this study was to evaluate the efficacy of tranexamic acid (TA) and tranexamic acid combined with vitamin C (TXC) on drainage volume (blood loss) and atrial fibrillation (AF) in patients undergoing cardiac bypass surgery in Gorgan, Shafa hospital, Iran.

METHODS

This study is a double-blind randomized clinical trial. A sample size of 120 candidates of cardiac bypass surgery were included in this prospective study. Patients were randomly assigned to treatments in two groups. In both groups, 50 mg/kg tranexamic acid was administered intravenously directly before sternotomy: group A (N = 58) patients received tranexamic acid (TA) only and group B (N = 62) tranexamic acid with vitamin C (TXC) half an hour before surgery and 2 g vitamin C with 100 mL 0.9% saline were injected. Subsequently, during 4 days after surgery, 1000 mg of vitamin C and 100 cc 0.9% saline was infused every day. Intraoperative and postoperative blood loss (volume of blood in the drain) and atrial fibrillation complications were recorded for 24 hours after the operation.

RESULTS

The patients who received vitamin C had less bleeding during operation and in the early hours post-operation. Patients in (TA) group had mean drainage of 34.41 milliliter more than patients in (TXC) group (P < 0.001). Chi-square test showed that arrhythmia (AF) condition was the same in the two groups during 14 times of study (four times during operation and ten times up to 24 hours after the operation), and AF arrhythmia in the two groups was less than 5%.

CONCLUSIONS

In this study tranexamic acid with vitamin C have a positive effect on the amount of drainage (blood loss) and there was no significant difference in the incidence of AF between two groups.

Perioperative use of renin-angiotensin system inhibitors and outcomes in patients undergoing cardiac surgery

It remains disputable about perioperative use of renin-angiotensin system inhibitors (RASi) and their outcome effects. This multicenter retrospective cohort study examines association between use of perioperative RASi and outcomes in patients undergoing coronary artery bypass graft and/or valve surgery. After the exclusion, the patients are divided into 2 groups with or without preoperative RASi (PreRASi, n = 8581), or 2 groups with or without postoperative RASi (PostRASi, n = 8130). With using of propensity scores matching to reduce treatment selection bias, the study shows that PreRASi is associated with a significant reduction in postoperative 30-day mortality compared with without one (3.41% vs. 5.02%); PostRASi is associated with reduced long-term mortality rate compared with without one (6.62% vs. 7.70% at 2-year; 17.09% vs. 19.95% at 6-year). The results suggest that perioperative use of RASi has a significant benefit for the postoperative and long-term survival among patients undergoing cardiac surgery.

Renin-angiotensin system inhibitors (RASi) are beneficial in several classes of cardiovascular patients. However, whether their perioperative use is beneficial and/or safe in cardiac surgery is unclear. Here the authors perform a multicenter retrospective cohort study showing that preoperative and postoperative use of RASi is associated with reduction of mortality in patients undergoing cardiac surgery.