Coronary artery bypass grafting in patients with low ejection fraction

Comparison of a coronary bypass surgery using a combination of both on-pump beating heart and cardioplegic arrest with conventional coronary bypass surgery using cardioplegic arrest on-pump

Objective

Antegrade cardioplegia may cause maldistribution in patients with multivessel coronary artery disease. Surgically bypassing large epicardial vessels before the cross-clamp and then administering cardioplegia from both the aortic root and the anastomosed grafts significantly prevent maldistribution and provide better cardiac protection.

Methods

This study included 80 patients, all older than 70 years with an ejection fraction between 25 and 35%. Patients were equally divided into two groups. Distal anastomoses to some of large epicardial coronary arteries were performed before the cross-clamp was placed. Grafted veins were attached to multi-perfusion set ports. Then, cross-clamping was performed, and the multi-perfusion set was disconnected from the aortic cannula and attached to the cardioplegia route. Antegrade cardioplegia was administered to both the aortic root and saphenous vein grafts. After all distal anastomoses were completed, the cross-clamp was removed, and the multi-perfusion set was connected to the aortic cannula again. Conventional coronary bypass techniques were used in group 2 patients.

Results

Inotropic agents were administered in 12 patients in group 1 and 29 patients in group 2 (p < 0.001). The average troponin I value in coronary sinus blood was 1.05 ± 0.8 ng/mL in group 1 and 3.12 ± 0.7 ng/mL in group 2 (p < 0.001). The average lactate value in coronary sinus blood was 1.15 ± 0.55 mmol/L in group 1 and 3.7 ± 2.4 mmol/L in group 2 (p < 0.001). Six patients died in the early postoperative period in group 2 (p = 0.028).

Conclusion

The current technique considerably reduces cross-clamping time and allows better distribution of the cardioplegic solution, preserving myocardium. Reduced coronary sinus lactate and troponin I levels also indicate better myocardial protection.

Perioperative Modulation of Left Ventricular Systolic Performance: A Retrospective Study on Ionized Calcium and Vitamin D in Cardiac Surgery Patients

Background: The perioperative impact of calcium and vitamin D on left ventricular (LV) performance during major cardiac surgery remains unexplored. We aimed to assess the relation of calcium and vitamin D measured at different time points with the LV ejection fraction (EF), and to investigate whether changes in EF correlate with postoperative outcomes. Methods: We enrolled 83 patients, in whom ionized calcium was measured before, during, and after surgery (until discharge), vitamin D preoperatively, and EF pre- and postoperatively at 24 h. The postoperative outcomes were cardiopulmonary bypass (CPB) time, aortic cross-clamp time, mechanical ventilation time, vasoactive inotropic score (VIS) (intraoperative, day 0, day 1), and ICU stay time. Results: The mean age was 64.9 ± 8.5 years, with 21 of the patients (25%) having an EF < 50%. The median change from preoperative to postoperative EF was -2.0 (-10.0-0.0) % (p < 0.001). At the baseline, the EF < 50% group had significantly lower preoperative vitamin D levels than the EF ≥ 50% group (p = 0.048). The calcium trend did not differ across the groups. Preoperative EF was significantly associated with CPB time (r = 0.22, p = 0.044) and aortic cross-clamp time (r = 0.24, p = 0.031). Postoperative EF was significantly and inversely associated with intraoperative VIS (r = -0.28, p = 0.009), VIS day 0 (r = -0.25, p = 0.020), VIS day 1 (r = -0.23, p = 0.036), and ICU length of stay (r = -0.22, p = 0.047). Finally, the change in ejection fraction was significantly and inversely associated with CPB time (r = -0.23, p = 0.037), aortic cross-clamp time (r = -0.22, p = 0.044), intraoperative VIS (r = -0.42, p < 0.001), VIS day 0 (r = -0.25, p = 0.024), mechanical ventilation time (r = -0.22, p = 0.047), and ICU length of stay (r = -0.23, p = 0.039). Conclusions: The fluctuations in perioperative ionized calcium levels were not associated with the evolution of LVEF, although preoperative vitamin D levels may affect those with low EF. Correspondingly, a reduced EF significantly impacted all the studied postoperative outcomes. Further investigation into biomarkers affecting cardiac inotropic function is warranted to better understand their significance.

Effects of different surgical strategies and left ventricular remodelling on the outcomes of coronary artery bypass grafting in heart failure patients with reduced ejection fraction

Background

Ischaemic heart failure with reduced ejection fraction (HFrEF) caused by coronary artery disease accounts for the largest proportion of heart failure cases with the worst prognosis. Coronary artery bypass grafting (CABG) is the most effective treatment for ischaemic HFrEF. On-pump and off-pump are the two surgical methods used for CABG. Whether patients with HFrEF should undergo on- or off-pump CABG is controversial in coronary heart disease surgery. The left ventricular end-systolic volume index (LVSEVI) is the gold standard for evaluating the severity of left ventricular remodelling; however, its effect on the perioperative risk and long-term survival rate of patients with HFrEF undergoing CABG remains unclear.

Methods

This single centre prospective cohort analysis included 118 coronary heart disease patients with symptoms and signs of heart failure and a left ventricular ejection fraction (LVEF) of <40% who were enrolled consecutively from January 2019 to December 2023. Operative mortality, perioperative complications, and long-term survival were compared among patients treated with various LVESVIs and surgical methods. The primary outcomes were cardiac death, myocardial infarction, heart failure, stroke, and revascularization, (percutaneous coronary intervention or redo CABG) with a median follow-up of 38 ± 10 months.

Results

The 30-day postoperative mortality of 118 patients was 6.8%. Patients in the off-pump group had significantly higher perioperative mortality than those in the on-pump group (12.5% vs. 3.8%, p = 0.03). In the off-pump group, a higher proportion of patients required perioperative mechanical assistance, such as intra-aortic artery balloon pump (IABP) or extracorporeal membrane oxygenation (ECMO), compared to those in the on-pump group (IABP: 75% vs. 47.4%, p = 0.004; ECMO: 22.5% vs. 1.3%, p = 0.000). Patients in the off-pump group were more likely to have postoperative atrial fibrillation (AF) (35% vs. 14.1%, p = 0.01). In the on-pump group, the incidence of postoperative AF (25% vs. 6.5%, p = 0.02) and IABP use (62.5% vs. 36.9%, p = 0.03) were significantly higher in patients with more severe left ventricular remodelling than in those with less severe left ventricular remodelling. In the off-pump group, patients with more severe left ventricular remodelling had higher ECMO usage (38.9% vs. 9.1%, p = 0.04), incidence of postoperative AF (61.1% vs. 13.6%, p = 0.02), and perioperative mortality (22.2%). Major adverse cardiac event (MACE)-free survival rate was significantly higher in the on-pump group than in the off-pump group, and there was no significant difference in MACE free survival rates between the two groups of patients with different degrees of left ventricular remodelling.

Conclusion

On-pump bypass is a better surgical procedure for patients with ischaemic HFrEF, especially those with severe left ventricular remodelling. Left ventricular remodelling increases perioperative mortality but has no effect on long-term survival.

Predicting outcomes in patients with low ejection fraction undergoing coronary artery bypass graft

Introduction

Reduced left ventricular ejection fraction (LVEF) is a well-known predictor of adverse events after cardiac surgery. We aimed to assess the outcomes in patients with low LVEF undergoing coronary artery bypass graft.

Methods

In this retrospective cohort, we included all patients with left ventricular ejection fraction ≤ 40 who underwent coronary artery bypass grafting between March 2007 and March 2016 (with a median follow-up of nine years) at Tehran Heart Center. Demographics and clinical characteristics were extracted from the data registry. Akaike information criterion (AIC) was used. The univariate Cox regression was performed. We investigated the predictors of mortality and major adverse cardiac and cerebrovascular events (MACCE) using Cox multivariable regression.

Results

In total, 5,532 cases (79 % male) with a mean age of 65.58 were included in the study. The nine-year overall survival was calculated at 68 %, and more than half of the patients had MACCE (55 %). In adjusted multivariable Cox regression analysis, moderate to severe mitral valve regurgitation, glomerular filtration rate ≤ 60, mild right ventricular dysfunction, and valvular heart disease independently predicted higher mortality. The abovementioned predictors and peripheral vascular disease significantly increased MACCE.

Conclusion

Our study indicates the clinical significance of mitral regurgitation, valvular heart disease, and renal function in patients with low ejection fraction treated by coronary artery bypass grafting surgery. Identifying predictors of adverse events can help with clinical decision-making and risk stratification, ultimately improving patient outcomes.

Sleep-Disordered Breathing, Advanced Age, and Diabetes Mellitus Are Associated with De Novo Atrial Fibrillation after Cardiac Surgery

Background: Postoperative de novo atrial fibrillation (POAF) is one of the most frequently encountered complications following cardiac surgery. Despite the identification of several risk factors, the link between sleep-disordered breathing (SDB) and POAF has barely been examined. The objective of this prospective observational study was to determine whether severe SDB is associated with POAF in patients after elective coronary artery bypass grafting (CABG) surgery. Study design and methods: The incidence and preoperative predictors of in-hospital POAF were assessed in 272 patients undergoing CABG surgery at the University Medical Center Regensburg (Germany). In-hospital POAF was detected by continuous telemetry-ECG monitoring and 12-lead resting ECGs within the first seven postoperative days. POAF that occurred after hospital discharge within 60 days post CABG surgery was classified as post-hospital POAF and was ascertained by standardized phone interviews together with the patients' medical files, including routinely performed Holter-ECG monitoring at 60 days post CABG surgery. The night before surgery, portable SDB monitoring was used to assess the presence and type of severe SDB, defined by an apnea-hypopnea index ≥ 30/h. Results: The incidence of in-hospital POAF was significantly higher in patients with severe SDB compared to those without severe SDB (30% vs. 15%, p = 0.009). Patients with severe SDB suffered significantly more often from POAF at 60 days post CABG surgery compared to patients without severe SDB (14% vs. 5%, p = 0.042). Multivariable logistic regression analysis showed that severe SDB (odds ratio, OR [95% confidence interval, CI]: 2.23 [1.08; 4.61], p = 0.030), age ≥ 65 years (2.17 [1.04; 4.53], p = 0.038), and diabetes mellitus (2.27 [1.15; 4.48], p = 0.018) were significantly associated with in-hospital POAF. After additional adjustment for heart failure, the association between sleep apnea and postoperative atrial fibrillation was attenuated (1.99 [0.92; 4.31], p = 0.081). Conclusions: Amongst established risk factors, severe SDB was significantly associated with in-hospital POAF in patients undergoing CABG surgery. Whether SDB contributes to POAF independently of heart failure and whether risk for POAF may be alleviated by proper treatment of SDB merits further investigation.

Prognostic factors of surgical management for heart failure patients with reduced left ventricular ejection fraction

Objectives

There are many available pharmaceutical and surgical management for Coronary artery disease (CAD) patients. However, coronary artery bypass grafting (CABG) is the preferred treatment modality for CAD patients with low ejection fraction (EF) in view of the more favorable outcomes. This study aimed to determine the associated factors of poor outcomes post-CABG for heart failure patients with reduced left ventricular ejection fraction who underwent on-pump and off-pump CABG.

Methods

A retrospective review of CAD patients who underwent isolated on-pump CABG (ONCAB) or off-pump CABG (OPCAB) in Beijing Anzhen Hospital Affiliated with Capital Medical University from January 2013 to March 2021. Only those with confirmed reduced left ventricular ejection fraction (LVEF) ≤40% on preoperative echocardiography were included. By analyzing the clinical and surgical data, postoperative mortality and morbidity, as well as major cardiovascular and cerebrovascular adverse events (MACCE) as endpoints, certain risk factors of the postoperative complications were identified.

Results

Out of the 500 patients, 64 developed MACCE, of which 14 (13.6%) occurred in the ONCAB group and 50 (14.0%) in the OPCAB group. Univariate COX regression analysis showed that age ≥65 years, history of diabetes, and preoperative renal insufficiency were independent risk factors for postoperative primary endpoint events in CAD patients with heart failure with reduced ejection fraction (HFrEF). Following the multivariate COX regression analysis, in addition to the above three risk factors, a history of previous percutaneous coronary angiography (PCI) intervention was also a risk factor for the occurrence of the primary endpoints post-CABG.

Conclusion

Based on the analysis, significant predictors of post-CABG MACCE in patients with HFrEF included being older than 65 years old, having diabetes, preoperative renal insufficiency, and having previous PCI.

Off-pump minimally invasive coronary artery bypass grafting in patients with left ventricular dysfunction: the lampang experience

Introduction

The minimally invasive cardiac surgery off-pump coronary artery bypass (MICSOPCAB) is technically difficult; therefore, previous studies have indicated that MICSOPCAB should be contraindicated in patients with impaired left ventricular (LV) function. In this study, we investigated the feasibility of MICSOPCAB in patients with impaired LV function.

Methods

The 226 patients underwent MICSOPCAB between August 2017 and September 2022. Our study defined impaired LV function as ejection fraction (EF) in echocardiography 40% or less. The patients were divided into Low EF group (n = 39) and Normal EF group (n = 187).

Results

The Low EF group was in a more critical preoperative condition than Normal EF group (41.0% in the Low EF group vs. 14.4% in the Normal EF group; p < 0.001). For preoperative transthoracic echocardiography, LV end-diastolic diameter (5.5 ± 0.9 cm in the Low EF group vs. 5.0 ± 0.8 cm in the Normal EF group; p < 0.001) and LV end-systolic diameter (4.4 ± 1.0 cm in the Low EF group vs. 3.4 ± 1.0 cm in the Normal EF group; p < 0.001) were significantly larger in the Low EF group. No differences were found in the operative time (180 [160-240] min in the Low EF group vs. 205 [165-253] min in the Normal EF group; p = 0.231) and the median number of distal anastomoses (2 [1-2] in the Low EF group vs. 2 [1-3] in the Normal EF group; p = 0.073). Intensive care unit stay was longer in the Low EF group than in the Normal EF group (2 [1-2] in the Low EF group vs. 1 [1-2] in the Normal EF group; p = 0.010). Perioperative transfusion was more common in the Low EF group than in the Normal EF group (69.7% vs. 49.2%; p = 0.023). There were no differences in major complications, hospital stay, and 30-day mortality. The Kaplan-Meier curve showed no significant difference in postoperative major adverse cardiac or cerebrovascular events rates between the two groups (p = 0.185).

Conclusion

In this study, MICSOPCAB can be performed in patients with low EF having short- and mid-term outcomes similar to patients with normal EF. Therefore, low EF should not be contraindicated in MICSOPCAB.

On- vs. Off-Pump CABG in Heart Failure Patients with Reduced Ejection Fraction (HFrEF): A Multicenter Analysis

OBJECTIVE

This study aimed to compare postoperative outcomes and 30-day mortality in patients with reduced ejection fraction (<40%) who underwent isolated coronary artery bypass grafting (CABG) with (ONCAB) and without (OPCAB) the use of cardiopulmonary bypass.

METHODS

data from four university hospitals in Germany, spanning from January 2017 to December 2021, were retrospectively analyzed. A total of 551 patients were included in the study, and various demographic, intraoperative, and postoperative data were compared.

RESULTS

demographic parameters did not exhibit any differences. However, the OPCAB group displayed notably higher rates of preoperative renal insufficiency, urgent surgeries, and elevated EuroScore II and STS score. During surgery, the ONCAB group showed a significantly higher rate of complete revascularization, whereas the OPCAB group required fewer intraoperative transfusions. No disparities were observed in 30-day/in-hospital mortality for the entire cohort and the matched population between the two groups. Subsequent to surgery, the OPCAB group demonstrated significantly shorter mechanical ventilation times, reduced stays in the intensive care unit, and lower occurrences of ECLS therapy, acute kidney injury, delirium, and sepsis.

CONCLUSIONS

the study's findings indicate that OPCAB surgery presents a safe and viable alternative, yielding improved postoperative outcomes in this specific patient population compared to ONCAB surgery. Despite comparable 30-day/in-hospital mortality rates, OPCAB patients enjoyed advantages such as decreased mechanical ventilation durations, shorter ICU stays, and reduced incidences of ECLS therapy, acute kidney injury, delirium, and sepsis. These results underscore the potential benefits of employing OPCAB as a treatment approach for patients with coronary heart disease and reduced ejection fraction.

Outcomes and Direct Cost of Isolated Nonemergent CABG in Patients With Low Ejection Fraction

OBJECTIVE

Preoperative left ventricular ejection fraction (LVEF) is one of the main predictors of outcomes in cardiac surgery. We present current era outcomes and associated direct cost in nonemergent isolated coronary artery bypass surgery (CABG) patients with LVEF <20% over the past 6 years and compare it with higher EF subgroups.

METHODS

Six-year data from 2016 to 2022 at hospitals sharing Society of Thoracic Surgeons and financial data with Biome Analytics were analyzed based on 3 EF subgroups (EF ≤20%, EF 21% to 35%, and EF >35%). Outcomes and costs were assessed.

RESULTS

Overall 30-day mortality of 12,649 patients was 1.9%. The EF ≤20% (n = 248), EF 21% to 35% (n = 1,408), and EF >35 (n = 10,993) cohorts had mortality of 6.9%, 3.7%, and 1.6%, respectively. The EF ≤20% subgroup had higher use of cardiopulmonary bypass, blood products, and mechanical support. In addition, the EF ≤20% subgroup had higher complication rates in almost all measured categories. Also, the EF ≤20% cohort had significantly higher length of stay, intensive care unit (ICU) hours, ICU and hospital readmissions, and lowest discharge to home rate. The strongest factors associated with mortality were postoperative cardiac arrest, renal failure requiring dialysis, extracorporeal membrane oxygenation, sepsis, prolonged ventilation, and gastrointestinal event. The overall median direct cost of care was $37,387.79 ($27,605.18, $51,720.96), with a median direct cost of care in the EF ≤20%, EF 21% to 35%, and EF >35% subgroups of $52,500.17 ($34,103.52, $80,806.79), $44,108.32 ($31,597.58, $63,788.03), and $36,521.80 ($27,168.91, $50,019.31), respectively.

CONCLUSIONS

In nonemergent isolated CABG surgery, low EF continues to have higher surgical risks and higher direct cost of care despite advances in cardiovascular care.

Comparison of Early and Long-Term Mortality in Patients With Reduced and Preserved Ejection Fraction Undergoing Coronary Artery Bypass Graft: A Systematic Review and Meta-Analysis

The aim of this study was to compare early and long-term mortality in patients with reduced and preserved ejection fraction (EF) undergoing coronary artery bypass graft (CABG). This meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. Two investigators independently conducted a systematic and comprehensive search of PubMed, EMBASE, and Scopus from inception to July 15, 2023, using the search terms "reduced ejection fraction," "preserved ejection fraction," "coronary artery bypass surgery," and "mortality." Boolean operators (AND, OR) were used with medical subject heading (MeSH) terms to refine the search. The reference lists of all included articles were manually searched to identify potentially relevant studies. We restricted our search to studies published in the English language. The outcomes assessed in this meta-analysis included short-term mortality (including in-hospital and 30-day mortality) and long-term mortality. A total of five studies were included in this meta-analysis. The pooled sample size is 94,399 participants. Pooled analysis showed that the risk of early mortality was significantly higher in patients with reduced EF compared to patients with preserved EF (risk ratio, RR: 2.14, 95% CI: 1.50 to 3.06). The pooled analysis also reported that late mortality was significantly higher in patients with reduced EF compared to patients with preserved EF (RR: 1.67, 95% CI: 1.35 to 2.08). The pooled analysis of studies demonstrated a significantly higher rate of both early and late mortality in patients with reduced EF, emphasizing the importance of EF assessment in risk stratification for CABG patients.

Coronary revascularization for heart failure with coronary artery disease: A systematic review and meta-analysis of randomized trials

AIMS

Coronary artery disease (CAD) is a common cause of heart failure (HF). Whether coronary revascularization improves outcomes in patients with HF receiving guideline-recommended pharmacological therapy (GRPT) remains uncertain; therefore, we conducted a systematic review and meta-analysis of relevant randomized controlled trials (RCTs).

METHODS AND RESULTS

We searched in public databases for RCTs published between 1 January 2001 and 22 November 2022, investigating the effects of coronary revascularization on morbidity and mortality in patients with chronic HF due to CAD. All-cause mortality was the primary outcome. We included five RCTs that enrolled, altogether, 2842 patients (most aged <65 years; 85% men; 67% with left ventricular ejection fraction ≤35%). Overall, compared to medical therapy alone, coronary revascularization was associated with a lower risk of all-cause mortality (hazard ratio [HR] 0.88, 95% confidence interval [CI] 0.79-0.99; p = 0.0278) and cardiovascular mortality (HR 0.80, 95% CI 0.70-0.93; p = 0.0024) but not the composite of hospitalization for HF or all-cause mortality (HR 0.87, 95% CI 0.74-1.01; p = 0.0728). There were insufficient data to show whether the effects of coronary artery bypass graft surgery or percutaneous coronary intervention were similar or differed.

CONCLUSIONS

For patients with chronic HF and CAD enrolled in RCTs, the effect of coronary revascularization on all-cause mortality was statistically significant but neither substantial (HR 0.88) nor robust (upper 95% CI close to 1.0). RCTs were not blinded, which may bias reporting of the cause-specific reasons for hospitalization and mortality. Further trials are required to determine which patients with HF and CAD obtain a substantial benefit from coronary revascularization by either coronary artery bypass graft surgery or percutaneous coronary intervention.

Days alive and out of hospital at 30 days and outcomes of off-pump coronary artery bypass grafting

Days alive and out of hospital (DAOH) is a simple estimator based on the number of days not in hospital within a defined period. In cases of mortality within the period, DAOH is regarded as zero. It has not been validated solely in off-pump coronary artery bypass grafting (OPCAB). This study aimed to demonstrate a correlation between DAOH and outcome of OPCAB. We identified 2211 OPCAB performed from January 2010 to August 2016. We calculated DAOH at 30 and 60 days. We generated a receiver-operating curve and compared outcomes. The median duration of hospital stay after OPCAB was 6 days. The median DAOH values at 30 and 60 days were 24 and 54 days. The estimated thresholds for 3-year mortality for DAOH at 30 and 60 days were 20 and 50 days. Three-year mortality was higher for short DAOH (1.2% vs. 5.7% and 1.1% vs. 5.6% DAOH at 30 and 60 days). After adjustment, the short DAOH 30 group showed significantly higher mortality during 3-year follow-up (hazard ratio 3.07; 95% confidence interval 1.45-6.52; p = 0.004). DAOH at 30 days after OPCAB showed a correlation with 3-year outcomes. DAOH 30 might be a reliable long-term outcome measure that can be obtained within 30 days after surgery.

Off-pump versus on-pump coronary artery bypass graft surgery outcomes in patients with severe left ventricle dysfunction: inverse probability weighted study

Objective

In this study we aimed to compare on-pump and off-pump coronary artery bypass grafting (CABG) outcomes in patients presented with low left ventricular ejection fraction (EF) as a high-risk group of patients.

Methods

In this registry-based study from 2014 and 2016, all patients with severe left ventricular dysfunction (EF less than 35%) were included and followed until 2020. The median follow-up period was 47.83 [38.41, 55.19] months. Off pump CABG (OPCABG) was compared with on-pump CABG (ONCABG) in terms of mid-term non-fatal cardiovascular events (CVEs) and all-cause mortality. Propensity score method (with inverse probability weighting technique) was used to compare these two groups.

Results

From 14,237 patients who underwent isolated CABG, 2055 patients with EF ≤ 35% were included; 1705 in ONCABG and 350 patients in OPCABG groups. Although OPCABG was associated with lower risk of 30-days mortality (Odds Ratio [OR]: 0.021; Confidence Interval [CI] 95% [0.01, 0.05], P < 0.001); there was no significant difference between OPCABG and ONCABG in term of mid-term mortality and non-fatal CVEs ((Hazard ratio [HR]: 0.822; 95%CI [0.605, 1.112], p = 0.208) and (HR: 1.246; 95%CI [0.805, 1.929], p = 0.324), respectively). Patients with more than three traditional coronary artery disease risk factors, had more favorable outcomes (in terms of mid-term mortality) if underwent OPCABG (HR: 0.420; 95%CI [0.178, 0.992], p = 0.048).

Conclusion

OPCABG was associated with lower risk of 30-days mortality; however, mid-term outcomes were comparable in both OPCABG and ONCABG techniques.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02895-0.

Myocardial Viability Testing in the Management of Ischemic Heart Failure

Although major advances have occurred lately in medical therapy, ischemic heart failure remains an important cause of death and disability. Viable myocardium represents a cause of reversible ischemic left ventricular dysfunction. Coronary revascularization may improve left ventricular function and prognosis in patients with viable myocardium. Although patients with impaired left ventricular function and multi-vessel coronary artery disease benefit the most from revascularization, they are at high risk of complications related to revascularization procedure. An important element in selecting the patients for myocardial revascularization is the presence of the viable myocardium. Multiple imaging modalities can assess myocardial viability and predict functional improvement after revascularization, with dobutamine stress echocardiography, nuclear imaging tests and magnetic resonance imaging being the most frequently used. However, the role of myocardial viability testing in the management of patients with ischemic heart failure is still controversial due to the failure of randomized controlled trials of revascularization to reveal clear benefits of viability testing. This review summarizes the current knowledge regarding the concept of viable myocardium, depicts the role and tools for viability testing, discusses the research involving this topic and the controversies related to the utility of myocardial viability testing and provides a patient-centered approach for clinical practice.

Preventive Impella® Support in High-Risk Patients Undergoing Cardiac Surgery

Background: Patients with severely reduced LV-EF ≤ 30% undergoing CABG have a high risk for postoperative cardiogenic shock. The optimal timing of an adequate hemodynamic support has an impact on short- and midterm mortality after CABG. This study aimed to assess the prophylactic use of the Impella pump in high-risk patients undergoing elective cardiac surgery. Methods: In this single-center retrospective study, 14 patients with LV-EF (≤30%) undergoing cardiac surgery received a prophylactic, perioperative Impella (5.0, 5.5) support between 2020 and 2022. Results: The mean age at surgery was 64.2 ± 2.6 years, the mean preoperative LV-EF was 20.7% ± 1.56%. The duration of Impella support was 4 (3–7.8) days and the 30-day survival rate was 92.85%. Acute renal failure occurred in four patients who were dialyzed on average for 1.2 ± 0.7 days. Mechanical ventilation was needed for 1.75 (0.9–2.7) days. Time to inotrope/vasopressor independence was 2 (0.97–7.25) days with a highest lactate level (24 h postoperatively) of 3.8 ± 0.6 mmol/l. Postoperative LV-EF showed a significant improvement when compared to preoperative LV-EF (29.1% ± 2.6% vs. 20.7% ± 1.56% (p = 0.022)). Conclusion: The prophylactic Impella application seems to be a safe approach to improve the outcomes of this patient population.

In-hospital mortality of patients with severe left ventricular dysfunction undergoing coronary artery bypass grafting in Iranian population

Background

Historically, coronary artery bypass grafting is associated with a higher mortality rate in patients with severe heart failure. This study aimed to assess the in-hospital mortality of CABG in patients with severe heart failure in Iranian patients and to identify factors associated with adverse outcomes.

Methods

This retrospective descriptive study enrolled patients with severe heart failure who underwent coronary artery bypass surgery from 2015 to 2020 in Madani Hospital, affiliated with Tabriz University of Medical Sciences.

Results

A total of 865 consecutive patients with a mean age of 60.65 ± 10.00 were enrolled in the study. Of all participants, 175 were female (20.4%), and 684 were male. The overall mortality rate was 9.5%. In the univariate analysis, predictors of ICU mortality were age, female sex, DM, and renal failure (P value < 0.05). None of the factors studied was an independent predictor of ICU mortality in the multivariate analysis.

Conclusion

This study established that although coronary artery bypass surgery is reported to have low mortality and postoperative morbidity in patients with severe heart failure, there are still centers that face higher mortality rates in these patients. Improving these patients' outcomes would be possible through identifying the associated risk factors and pre-and postoperative management.

Pre-operative, Intraoperative, and Post-operative Determinants Associated with 30-day Mortality Post-Coronary Artery Bypass Graft: A Retrospective Cohort Study

Abstract Background: Various determinants of 30-day mortality risk in CABG patients have been formulated into certain scoring models such as the EuroSCORE and ACEF model. However, these models only consider preoperative parameters while excluding intraoperative, postoperative, and perioperative parameters. Currently, the prior research has increasingly emphasized the role of these excluded parameters as determinants of post-CABG mortality. Furthermore, there are differences in mortality rate of CABG procedures in Indonesia when compared with other countries. Hence, this study aimed to identify preoperative, intraoperative, and postoperative determinants of 30-day mortality after CABG surgery in Indonesian population. Methods: In this retrospective cohort study, secondary data were obtained from the medical records of 263 patients aged ≥ 18 years who underwent CABG at a single center in Indonesia during the year 2012–2015. Selected preoperative, intraoperative, postoperative, and perioperative determinants were analyzed in both bivariate and multivariate Cox regression models to identify determinants associated with 30-day mortality. Results: The 30-day mortality rate after CABG was 11.8%. Multivariate analysis identified neurological dysfunction (HR 6.16; 95% CI 2.42-15.66), renal impairment (HR 3.9; 95% CI 1.46-10.38), left ventricle dysfunction (HR 3.53;95% CI 1.55-8.03), aortic clamp duration (HR 3.7;95% CI 1.53-8.96), surgery duration (HR 3.85;95% CI 1.39-10.70), postoperative thrombocytopenia (HR 3.99;95% CI 1.72-9.23), and postoperative intra-aortic balloon pump (HR 10.98; 95% CI 4.77-25.28) as significant determinants associated with 30-day mortality after CABG Conclusions: Neurological dysfunction, renal impairment, left ventricle dysfunction, aortic clamp duration, surgery duration, postoperative thrombocytopenia, and postoperative intra-aortic balloon pump were independent determinants for 30-day mortality after CABG.

The Effect of Low Preoperative Ejection Fraction on Mortality After Cardiac Surgery in Indonesia

Background

Among cardiac surgery patients, low preoperative left ventricular ejection fraction (LVEF) is common and has been associated with poor outcomes. The objective of this study was to assess the association between LVEF and postoperative mortality in patients undergoing open-heart surgery in several hospitals in Indonesia.

Methods

We conducted a multicenter study with the retrospective design using data from patients undergoing open-heart surgery in 4 institutions in Indonesia. Data regarding LVEF and other potential risk factors were extracted from medical records and compiled in one datasheet. Statistical analyses were performed to assess if low LVEF was associated with postoperative mortality and identify other potential risk factors.

Results

A total of 4789 patients underwent cardiac surgery in participating centers during the study period. Of these, 189 subjects (3.9%) had poor preoperative LVEF. Poor LVEF was associated with postoperative mortality (adjusted OR 2.761, 95% CI 1.763–4.323, p < 0.001). Based on types of surgery, LVEF had a significant association with mortality only in CABG patients, while there was no such association in valve surgery and inconclusive in congenital surgery patients. Other significant independent predictors of in-hospital mortality included age more than 65 years old, non-elective surgery, the complexity of procedures, history of cardiac surgery, organ failure, CARE score ≥ 3, NYHA class ≥ III, and poor right ventricular function.

Conclusion

Patients with low preoperative LVEF undergoing open-heart surgery had a higher risk of postoperative mortality. Cardiac surgery can be performed with acceptable mortality rates. Accurate selection of patients, risk/benefit evaluation, and planning of surgical and anesthesiological management are mandatory to improve outcomes.

Robotic Off-Pump Totally Endoscopic Coronary Artery Bypass in Patients With Low Ejection Fraction

Objective: Robotic totally endoscopic coronary bypass (R-TECAB) has been shown to be a safe and effective technique with excellent outcomes. The aim of this study is to assess the feasibility of R-TECAB in patients with low left ventricular ejection fraction (LVEF) and to report our midterm outcomes with up to 7-year follow-up. Methods: All patients undergoing R-TECAB at our institution between July 2013 and July 2020 were retrospectively reviewed. A total of 100 patients were identified with low LVEF defined as ≤40%. The preoperative characteristics, perioperative and postoperative outcomes, as well as the midterm results were reviewed. Results: The mean LVEF was 31%, and 62% of all patients had preexisting congestive heart failure. Of the cohort, 59% had 3-vessel disease and 6% underwent previous cardiac surgery. Multivessel TECAB was performed in 54%. Hybrid coronary revascularization occurred in 36 individuals. Two patients required cardiopulmonary bypass, and 35% were extubated in the operating room. No sternotomy conversions were required. One patient underwent reoperation for bleeding. No perioperative stroke, myocardial infarction, or mortality occurred. The left internal mammary artery graft patency was 97% at a mean of 1.6 months in the staged hybrid percutaneous coronary intervention group. At midterm follow-up the cardiac-related mortality was 5%. Heart transplant or left ventricular assist device was required in 4 patients, and 1 patient experienced a myocardial infarction. Freedom from major adverse cardiac events was 89%. Conclusions: Off-pump TECAB can be successfully performed in patients with low LVEF in the setting of an experienced and dedicated robotic cardiac surgery team. Our data demonstrate the feasibility of the technique with excellent perioperative and midterm outcomes.

Significance of preoperative left ventricular ejection fraction in 5-year outcome after isolated CABG

BACKGROUND

Pre-operative ejection fraction (EF) and comorbidities affect post-op outcomes. We aimed to compare the mortality and adverse events of patients with different baseline EF and also to evaluate the distribution of comorbidities in each EF group.

METHODS

A total of 20,937 patients who underwent isolated coronary artery bypass graft (CABG) surgery from January 2006 to December 2016 was included. Patients were divided into three groups based on their pre-operative left ventricular EF as follows; (1) Normal: EF ≥ 50%; (2) Mild to moderately reduced: 50% < EF ≤ 35%; and (3) Severely reduced: EF < 35%. The backward elimination method was considered for multivariate Cox-regression analysis to locate predictors of mortality and non-fatal cerebro-cardiovascular events (CCVEs). The median follow-up time was 5.61 [3.12-8.0] years.

RESULTS

The mean age in the total population was 60.94 ± 9.51 years and 73.6% of the total population was male. Diabetes mellitus was the common risk factor of mortality and CCVE in all EF groups. Impaired renal function (GFR < 60 ml/min) was associated with a higher risk of mortality after CABG regardless of EF level. The median 5-year mortality rate in patients with normal EF, mild-moderately reduced EF and severely reduced EF were 9.5%, 12.8%, and 22.7% respectively (P < 0.001). Although the trend of CCVEs was higher in severe left ventricle (LV) dysfunction, it was not statistically significant (p = 0.071).

CONCLUSION

Patients with severely reduced EF are at higher risk of mortality after CABG compared to those with higher EF levels; however, the rate of CCVEs may not be necessarily higher after adjustment for multiple pre-operative comorbidities.

Conventional cardiac surgery in patients with end-stage coronary artery disease: yesterday and today

Surgical therapy of combined coronary artery disease (CAD) and heart failure, also referred to as end-stage CAD, has evolved throughout the years and patients are currently being offered traditional coronary artery bypass grafting (CABG), with or without surgical ventricle restoration (SVR), interventions for ischemic mitral valve regurgitation, heart transplantation or implantation of mechanical cardiovascular support systems. Among surgical methods, operative myocardial revascularization (with or without ventricle restoration) is still playing an important role, aiming at restoration of proper myocardial perfusion, especially if heart muscle viability is present. Facing the donor shortage, CABG may constitute a valuable alternative to transplantation in selected patients. In individuals considered not suitable for surgical revascularization, implantation of mechanical circulatory support (MCS) not only appears as a salvage procedure, but also allows for reevaluation of future therapy directions. This article aims at providing an overview of evolving and current surgical practices in patients with end-stage CAD.

Association of Both High and Low Left Ventricular Ejection Fraction With Increased Risk After Coronary Artery Bypass Grafting

BACKGROUND

While reduced left ventricular ejection fraction (LVEF) is a known risk factor for complications after coronary artery bypass grafting (CABG), the relevance of higher LVEF values has not been established. Currently, most risk stratification tools consider LVEF values above a certain point as normal. However, since this does not account for insufficient ventricular filling or increased adrenergic tone, higher values may have clinical significance. To improve our understanding of this situation, we investigated the relationship of preoperative LVEF values with short- and long-term outcomes after CABG using a strategy that allowed for the identification of nonlinear relationships. We hypothesised that both higher and lower values are independently associated with increased postoperative complications and death in this population.

METHODS

We performed a single-centre retrospective cohort study of patients undergoing isolated CABG surgery. All patients had a preoperative measurement of their LVEF. Surgery involving mitral valve repair was excluded in order to eliminate the impact of mitral regurgitation. The primary outcome was long-term mortality; secondary outcomes included atrial fibrillation, operative mortality, and a composite outcome including any postoperative adverse event. Fractional polynomial equations were used to model the relationship between LVEF and outcomes so we could account for nonlinear relationships if present. Adjustments for confounders were made using multivariable logistic regression and Cox models.

RESULTS

A total of 7,932 subjects were included in the study. After adjusting for patient and surgical characteristics, LVEF remained associated with the primary outcome as well as the composite outcome of any postoperative adverse event. Both these relationships were best described by a J-shaped curve given that higher LVEF values were associated with increased risk, albeit not as high has lower values. Regarding long-term mortality, individuals with a preoperative LVEF of 60% demonstrated the longest survival. A statistically significant relationship was not found between LVEF and operative mortality or atrial fibrillation after adjustment for confounders.

CONCLUSIONS

Higher preoperative LVEF values may be associated with increased risk for patients undergoing CABG surgery. Future studies are needed to better characterise this phenotype.

Preoperative, Multidisciplinary Clinical Optimization of Patients with Severely Depressed Left Ventricular Ejection Fraction Who Are Undergoing Coronary Artery Bypass Grafting

Coronary artery bypass grafting (CABG) remains a routine operation despite major advancements in angioplastic procedures. Around 200,000 CABG procedures are performed annually in the U.S. Patients who are not candidates for angioplasty intervention often have advanced coronary disease and comorbidities that raise the risk of heart failure with decreased ejection fraction to around 25%. Over the years, significant developments in various preoperative interventions have occurred; in this paper, we suggest a multidisciplinary preoperative algorithm that can be included in a regularly scheduled multidisciplinary care plan.

The effect of ejection fraction on mortality in Coronary Artery Bypass Grafting (CABG) patients

Background and Objectives

Patients with low ejection fraction undergoing isolated CABG surgery are at a higher risk for postoperative complications and mortality. This study was conducted to evaluate the impact of ejection fraction on the outcome of isolated Coronary Artery Bypass Grafting (CABG).

Methods

Between July, 2017 to May, 2019 total 1214 patients underwent isolated CABG. Patients were divided into three groups based on their pre-operative Ejection Fraction (EF). Group-I included 625 patients with EF >50% [Normal EF], Group-II included 484 patients with EF 35-50% [Mild to Moderately Reduced EF], and Group 3 included 105 patients with EF<35% [Severely Reduced EF].

Results

The mean age of Group-I was 57.58 ± 9.206, Group-II was 58.38±9.124 and Group-III was 58.81± 8.663. The male gender was the predominant gender in all three groups: 194(41.1%) in Group-I, 201(52.6%) in Gp2, 52 (61.9%) in Group-III. 231(36.9) patients in Group-I, 234(48.3)in Group-II and 59(56.2) in Group-III had raised creatinine pre operatively. 5(0.8%) patients in Group-I, 2(0.4%) in Group-II and 3(2.9%) in Group-III had history of CVA. Hypertension was present in approximately 60% of all our patients. In the per-operative period 20(3.2%) patients in Group-I required an IABP as compared to 73(15.1%) in Group-II and 41(39.0%) in Group-III. The mean post-operative mortality in Group-I was 19 (3%), Group-II was 24(5.0%) and low EF group was 9(8.6%).

Conclusions

The results clearly indicate that worsening pre-operative ejection fraction is associated with a higher mortality post-operatively in patients undergoing isolated CABG. In addition, use of IABP increases as pre-operative LVEF decreases.

Evaluation of β-blocker therapy for long-term outcomes in patients with low ejection fraction after cardiac surgery

Background

Preoperative low left ventricular ejection fraction (LVEF) has been reported as an independent risk factor for in-hospital mortality. However, there were few studies evaluating the long-term mortality in these patients. We, therefore, conducted this study to investigate long-term outcomes of surgery on patients with LVEF≤35% undergoing a broad range of cardiac procedures.

Methods

We performed a retrospective cohort study in 510 patients from January 1, 2007 to September 1, 2019. These patients were divided into survival group (n = 386) and non-survival group (n = 124). The multivariate Cox analysis was used to estimate the risk factors for survival. In Cox analysis, β-blockers were indicated to be associated with long-term mortality. To further address bias, we derived a propensity score predicting the function of β-blockers on survival, and matched 52 cases to 52 controls with similar risk profiles.

Results

Patients were followed for a median period of 24 months (interquartile range: 11–44 months). Multivariate Cox regression analysis indicated that the non-survival group had higher weight, higher EuroSCORE, more smoking patients, longer time of cardiopulmonary bypass (CPB), more intra-aortic balloon pump (IABP) use, and more patients who always used β-blocker (HR: 2.056, 95%CI:1.236–3.420, P = 0.005) compared with survival group. After propensity matching, the group which always used β-blocker showed higher rate of all-cause death compare with the control group (61.54% vs 80.77%, P = 0.030).

Conclusions

The risk factors for long-term survival were weight, EuroSCORE, smoking, CPB, IABP, always used β-blockers in patients with LVEF≤35%. The discharge prescription of β-blocker should be cautiously administrated in those patients.

Short-term outcomes of on- vs off-pump coronary artery bypass grafting in patients with left ventricular dysfunction: a systematic review and meta-analysis

Objectives

Does the manipulation of the off-pump CABG (OPCAB) in patient with depressed left ventricular function is better than on-pump CABG (ONCAB) approach in in-hospital mortality and morbidities? Here we undertook a meta-analysis of the best evidence available on the comparison of primary and second clinical outcomes of the off-pump and on-pump CABG.

Design

Systematic literature reviewer and meta-analysis.

Data sources

PubMed, EMBASE, Web of science and Cochrane Center Registry of Controlled Trials were searched the studies which comparing the use of the off-pump CABG(OPCAB) and on-pump CABG (ONCAB) for patients with LVD during January 1990.1 to January 2018.

Eligibility criteria

All observation studies and randomized controlled trials comparing on-pump and off-pump as main technique for multi-vessel coronary artery disease (defined as severe stenosis (>70%) in at least 2 major diseased coronary arteries) with left ventricular dysfunction(defined as ejection fraction (EF) 40% or less) were included.

Data extraction and synthesis

Authors will screen and select the studies extract the following data, first author, year of publication, trial characters, study design, inclusion and exclusion criteria, graft type, clinical outcome, assess the risk of bias and heterogeneity. Study-specific estimates will pool through the modification of the Newcastle-Ottawa scale for the quality of study and while leave-one-out analysis will be used to detect the impact of individual studies on the robustness of outcomes.

Results

Among the 987 screened articles, a total of 16 studies (32,354 patients) were included. A significant relationship between patient risk profile and benefits from OPCAB was found in terms of the 30-day mortality (odds ratio [OR], 0.84; 95% confidence interval [CI], 0.73–0.97; P = 0.02), stroke (OR, 0.69; 95% CI, 0.55–0.86; P = 0.00), myocardial infarction (MI) (OR, 0.71; 95% CI, 0.53–0.96; P = 0.02), renal failure (OR, 0.71; 95% CI, 0.55–0.93; P = 0.01), pulmonary complication (OR, 0.68; 95% CI, 0.52–0.90; P = 0.01), infection (OR, 0.67; 95% CI, 0.49–0.91; P = 0.00),postoperative transfusion (OR, 0.25; 95% CI, 0.08–0.84; P = 0.02) and reoperation for bleeding (OR, 0.56; 95% CI, 0.41–0.75; P = 0.00). There was no significant difference in atrial fibrillation (AF) (OR, 0.96;95%; CI, 0.78–1.41; P = 0.56) and neurological dysfunction (OR, 0.88; 95% CI, 0.49–1.57; P = 0.65).

Conclusions

Compared with the on-pump CABG with LVD, using the off-pump CABG is a better choice for patients with lower mortality, stroke, MI, RF, pulmonary complication, infection, postoperative transfusion and reoperation for bleeding. Further randomized studies are warranted to corroborate these observational data.

A comparison of immediate postoperative complications in using left internal mammary artery + vein versus only vein as conduit in patients undergoing off-pump coronary artery bypass grafting

Objective:

The objective of the study is to compare the immediate postoperative cardiac complications in patients undergoing off-pump coronary artery bypass grafting (OPCABG) using mixed (arterial and venous grafts) versus only venous grafts and to compare the requirement of packed red cell units and intra-aortic balloon pump (IABP) in both the groups.

Materials and Methods:

This was an observational, analytical, prospective study.

Sample Size:

Fifty new patients were included in the study.

Inclusion/Exclusion Criteria:

Patients diagnosed with triple-vessel coronary artery disease (CAD) undergoing OPCABG with an ejection fraction (EF) of more than 30%. Patients who have undergone prior CABG, EF <30%, preexisting valvular heart disease, any evidence pulmonary hypertension, preoperative IABP, any history of neurological dysfunction, left atrium size more than 5.5 cm, and history of coagulation disorder was excluded from the study.

Results:

The most common immediate postoperative cardiac complication observed was atrial fibrillation followed by ventricular arrhythmias in both the groups. There was no statistically significant difference in complication rate between the two groups. Postoperative requirement of IABP and requirements of blood products were also similar in both the groups.

Conclusion:

Patients undergoing off-pump CABG have similar immediate postoperative complications irrespective of the type of conduit used.

Left ventricular function outcome after coronary artery bypass grafting, King Abdullah Medical City (KAMC)- single-center experience

Background

Coronary artery bypass grafting is known to be associated with better outcome in ischemic heart disease patients with low ejection fraction. We aim to demonstrate the effect of coronary artery bypass grafting (CABG) on left ventricle (LV) systolic function and to identify the predictors that adversely lead to postoperative poor outcome.

Result

This is a cross-sectional prospective study; we included 110 patients with left ventricular ejection fraction (LVEF) < 50% who underwent CABG with a mean age of 56.1 ± 12.2 years old. Those patients were classified into two groups: group I, 76 (69%) patients with LVEF > 35%, and group II, 34 (31%) patients with LVEF < 35%. Our results as regards demographic and clinical data revealed that group II patients had a significantly higher prevalence of diabetes mellitus (DM) and Euro SCORE II compared to group I patients (p = 0.05 and < 0.001 respectively); otherwise, all other clinical predictors did not differ between the two studied groups. There was a significant improvement in LVEF post-surgery (p = 0.05) in both groups with observed no significant difference recorded for in-hospital mortality rate among patients with different groups. DM, significant diastolic dysfunction, and insertion of IABP are predictors of in-hospital mortality of the patients (p = 0.001, 0.03 and < 0.001, respectively)

Conclusion

We concluded that there is a significant improvement of LV systolic function after CABG and hence better survival rate. DM, significant diastolic dysfunction, and perioperative insertion of IABP are predictors of mortality after cardiac surgery. Special care should be provided to such patients to improve their outcome

Levosimendan in patients with reduced left ventricular function undergoing isolated coronary or valve surgery

OBJECTIVE

In the Levosimendan in Patients with Left Ventricular Systolic Dysfunction Undergoing Cardiac Surgery Requiring Cardiopulmonary Bypass (LEVO-CTS) trial, no differences in clinical outcomes were observed between levosimendan and placebo in a broad population of patients undergoing cardiac surgery. In previous studies, the benefits of levosimendan were most clearly evident in patients undergoing isolated coronary artery bypass grafting (CABG) surgery. In a prespecified analysis of LEVO-CTS, we compared treatment-related outcomes and costs across types of cardiac surgical procedures.

METHODS

Overall, 563 (66.4%) patients underwent isolated CABG, 97 (11.4%) isolated valve, and 188 (22.2%) combined CABG/valve surgery. Outcomes included the co-primary 4-component composite (30-day mortality, 30-day renal replacement, 5-day myocardial infarction, or 5-day mechanical circulatory support), the 2-component composite (30-day mortality or 5-day mechanical circulatory support), 90-day mortality, low cardiac output syndrome (LCOS), and 30-day medical costs.

RESULTS

The 4- and 2-component outcomes were not significantly different with levosimendan and placebo in patients undergoing CABG (15.2% vs 19.3% and 7.8% vs 10.4%), valve (49.0% vs 33.3% and 22.4% vs 2.1%), or combined procedures (39.6% vs 35.9% and 24.0% vs 19.6%). Ninety-day mortality was lower with levosimendan in isolated CABG (2.1% vs 7.9%; hazard ratio [HR], 0.26; 95% confidence interval [CI], 0.11-0.64), but not significantly different in valve (8.3% vs 2.0%; HR, 4.10; 95% CI, 0.46-36.72) or combined procedures (10.4% vs 7.6%; HR, 1.39; 95% CI, 0.53-3.64; interaction P = .011). LCOS (12.0% vs 22.1%; odds ratio, 0.48; 95% CI, 0.30-0.76; interaction P = .118) was significantly lower in levosimendan-treated patients undergoing isolated CABG. Excluding study drug costs, median and mean 30-day costs were $53,707 and $65,852 for levosimendan and $54,636 and $67,122 for placebo, with a 30-day mean difference (levosimendan - placebo) of -$1270 (bootstrap 95% CI, -$8722 to $6165).

CONCLUSIONS

Levosimendan was associated with lower 90-day mortality and LCOS in patients undergoing isolated CABG, but not in those undergoing isolated valve or combined CABG/valve procedures.

[Predictors of early occlusion of coronary bypass grafts in patients with extremely low ejection fraction]

The authors carried out a retrospective study aimed at revealing predictors of early incompetence of coronary bypass grafts in patients with the ejection fraction below 30%. The study included a total of 104 patients presenting with coronary artery disease and the ejection fraction below 30%, who over the period from 2009 to 2016 underwent coronary artery bypass grafting with the use of autovenous and autoarterial conduits. 77 patients endured plasty of an aneurysm of the left ventricle (LV), 89 patients sustained plasty of the valvular apparatus. All patients were subjected to control coronary bypass angiography (CBA) within 12 postoperative months. Thus, we analysed a total of 184 autoarterial and 84 autovenous shunts. The findings of CBA revealed occlusions of 2 (1%) arterial and 10 (11%) venous conduits. Analysing the coronary bypass angiographies of the patients ranked according to the values of the effective stroke volume index demonstrated the following regularity: a decrease in the LV effective stroke volume index of less than 30 ml/m2 was accompanied bу increased incidence of thrombosis of autovenous shunts in the immediate postoperative period. Predictors of early occlusion of coronary bypass grafts were revealed by means of the Cox regression analysis. It was determined that using an autovein increased the risk of occlusion of the shunt by 26%, a decrease in the effective stroke volume index of the left ventricle by 1 ml/m2 increased the risk of early occlusion of coronary bypass grafts by 18%, a decrease in the diameter of the shunted artery by 0.5 mm increased the risk for early occlusion of the shunt by 12%, a decrease in the blood flow velocity (Qmean) by 1 ml/m2 increased the risk for occlusion of the shunt by 10%, a decrease in the peripheral resistance index (RI) by 1 unit elevated the risk of early occlusion of the bypass graft by 12%. Analysing the revealed independent predictors with the help of the neural network method demonstrated that the strongest influence on early incompetence of the coronary bypass graft was exerted by the type of the conduit and effective stroke index.

Coronary artery bypass grafting in patients with low ejection fraction: what are the risk factors?

BACKGROUND

Left ventricular (LV) dysfunction alone is insufficient as an independent predictor of postoperative complications and mortality in coronary artery bypass graft (CABG) surgery. Our objective was to identify additional independent risk factors in patients with low left ventricle ejection fraction (EF) who underwent CABG.

METHODS

We retrospectively analyzed CABG results of 346 consecutive patients with low EF (≤30%) in a single institution between 2009 and 2015. The primary study endpoint was 30-day all-cause mortality. The secondary endpoints were the development of major adverse cardiac events (MACE) and renal complications after operation. A subgroup of patients underwent additional analyses of the interaction between extents of viable myocardium and postoperative endpoints.

RESULTS

The analysis showed that preoperative hemodynamic instability (AOR=4.57; 95% CI: 1.53-13.7, P=0.007) and serum creatinine >166 µmol/L (AOR=3.46; 95% CI: 1.12-10.7, P=0.031) were independent predictors of 30-day death. Both urgent and emergency operations were predictors for MACE (P=0.038; P=0.005) and renal complications (P=0.004; P=0.007). Pre-existing diabetes mellitus increased the likelihood of renal complications (P=0.020). In the sub-analysis of patients with viable myocardium, the mortality was significantly lower with predicted mortality (P=0.014).

CONCLUSIONS

Patients with significant LV dysfunction undergoing isolated CABG have fair short-term survival even with EF less than 30%. Hemodynamic instability prior to operation and preoperative kidney dysfunction are strong predictors of mortality in patients with low EF. Favorable coronary targets, meticulous operative techniques, and optimal surgical timing before hemodynamic deterioration occurs are essential to minimize the risk of revascularization complications and early postoperative mortality.

CABG in patients with left ventricular dysfunction: indications, techniques and outcomes

Ischemic chronic heart failure (CHF) represents one of the cardiovascular diseases with the worst degree of morbidity and mortality in the western world, and with the highest health care costs. Despite several studies demonstrated that surgical revascularization (CABG), especially in the presence of viable myocardium, improve heart function, and therefore, survival, the matter remains unclear and controversial. In the late 1970s, the Coronary Artery Surgery Study showed that a subgroup of patients with coronary artery disease, angina, and reduce LV function had a significant survival benefit after CABG compared to those treated medically. The key concept behind this observation was the presence of viable myocardium, which can resume function following revascularization. In contrary, the surgical treatment for ischemic heart failure (STICH) trial, which randomized patients with CAD and LV dysfunction to evidence-based medical therapy or CABG plus medical therapy, failed to demonstrate at a median follow-up of 56 months a significant difference between the CABG group and the medical therapy group in the rate of death from any cause. However, the results of the STICH extension study (STICHES) at 10 years follow-up demonstrated that CABG is associated with a significant reduction in all-cause mortality, cardiovascular mortality, and readmission for heart compared to optimal medical therapy (OMT) in patients with severe ischemic LV dysfunction. Therefore, this review discusses the available evidences in literature, from observational studies to randomized trials, including operative techniques and controversial issues, in order to better clarify the role of CABG in the current management of ischemic patients with LVD.

Postoperative complications after elective coronary artery bypass grafting surgery in patients with sleep-disordered breathing

BACKGROUND

Sleep-disordered breathing (SDB) may increase the risk of postoperative complications in patients after cardiac surgery. This study evaluated the length of hospital stay as well as postoperative cardiac, respiratory, and renal complications after elective coronary artery bypass grafting (CABG) in patients without SDB, with central sleep apnea (CSA), or with obstructive sleep apnea (OSA).

METHODS

The presence and type of SDB had been assessed with polygraphic recordings in 100 patients the night before elective CABG surgery. SDB was defined as an apnea-hypopnea index (AHI) of ≥ 15/h. Prolonged length of hospital stay (LOS) and postoperative hemodynamic instability due to any cause were retrospectively evaluated as primary endpoints and cardiac, respiratory, and renal complications as secondary endpoints.

RESULTS

37% of patients had SDB, 14% CSA, and 23% OSA. LOS differed significantly between patients without SDB and those with CSA and OSA [median (25;75. percentile): 8.0 days (7.5;11.0) vs. 9.5 days (7.0;12.5) vs. 12.0 days (9.0;17.0), Kruskal-Wallis test between three groups: p = 0.023; OSA vs. no SDB: p = 0.005]. AHI was significantly associated with prolonged LOS [> 9 days; odds ratio (OR) (95% confidence interval): 1.047 (1.001;1.095), p = 0.044]. Prolonged need of vasopressors (≥ 48 h) was observed in 36% of patients without SDB, in 64% with CSA, and in 62% with OSA (p = 0.037). AHI was significantly associated with prolonged (≥ 48 h) need of vasopressors [OR (95% CI): 1.052 (1.002;1.104), p = 0.040], independent of any confounders.

CONCLUSIONS

SDB, particularly OSA, is associated with prolonged LOS after CABG, independent of known confounders. Prolonged LOS in patients with SDB may be due to increased postoperative hemodynamic instability due to any cause.

Levosimendan in Patients with Left Ventricular Dysfunction Undergoing Cardiac Surgery: An Update Meta-Analysis and Trial Sequential Analysis

BACKGROUND

Recent studies suggest that levosimendan does not provide mortality benefit in patients with low cardiac output syndrome undergoing cardiac surgery. These results conflict with previous findings. The aim of the current study is to assess whether levosimendan reduces postoperative mortality in patients with impaired left ventricular function (mean EF ≤ 40%) undergoing cardiac surgery.

METHODS

We conducted a comprehensive search of PubMed, EMBASE, and Cochrane Library Database through November 20, 2017. Inclusion criteria were random allocation to treatment with at least one group receiving levosimendan and another group receiving placebo or other treatments and cardiac surgery patients with a left ventricular ejection fraction of 40% or less. The primary endpoint was postoperative mortality. Secondary outcomes were cardiac index, pulmonary capillary wedge pressure (PCWP), length of intensive care unit (ICU) stay, postoperative atrial fibrillation, and postoperative renal replacement therapy. We performed trial sequential analysis (TSA) to evaluate the reliability of the primary endpoint.

RESULTS

Data from 2,152 patients in 15 randomized clinical trials were analyzed. Pooled results demonstrated a reduction in postoperative mortality in the levosimendan group [RR = 0.53, 95% CI (0.38-0.73), I2 = 0]. However, the result of TSA showed that the conclusion may be a false positive. Secondary outcomes demonstrated that PCWP, postoperative renal replacement therapy, and length of ICU stay were significantly reduced. Cardiac index was greater in the levosimendan group. No difference was found in the rate of postoperative atrial fibrillation.

CONCLUSIONS

Levosimendan reduces the rate of death and other adverse outcomes in patients with low ejection fraction who were undergoing cardiac surgery, but results remain inconclusive. More large-volume randomized clinical trials (RCTs) are warranted.

Off-pump versus on-pump coronary artery bypass grafting-a surreal controversy?

As per the findings of the SYNTAX Trial, it has been established that coronary artery bypass grafting (CABG) affords the best long-term results in patients with multivessel disease. However, it is still a point of contention whether 'off-pump' CABG (OPCAB) (on cardiopulmonary bypass) is better. Many studies appear to establish the superiority of one or the other. But there is still no well-planned multi-centre randomised controlled trial looking into all aspects of the issue that can, once and for all, put the controversy to rest. But as long as one is able to give the patient a good result, does it really matter whether the procedure is done off or on pump? This article looks at the available evidence with regard to various parameters comparing OPCAB and conventional CABG in an attempt to answer the question, if at all, it is a question!

Modifying risks to improve outcome in cardiac surgery: An anesthesiologist's perspective

Challenging times are here for cardiac surgical and anesthesia team. The interventional cardiologist seem to have closed the flow of ‘good cases’ coming up for any of the surgery,; successful percutaneous interventions seem to be offering reasonable results in these patients, who therefore do not knock on the doors of the surgeons any more. It is a common experience among the cardiac anesthesiologists and surgeons that the type of the cases that come by now are high risk. That may be presence of comorbidities, ongoing medical therapies, unstable angina, uncontrolled heart failure and rhythm disturbances; and in patients with ischemic heart disease, the target coronaries are far from ideal. Several activities such as institution of preoperative supportive circulatory, ventilatory, and systemic disease control maneuvers seem to have helped improving the outcome of these ‘high risk ‘ patients. This review attempts to look at various interventions and the resulting improvement in outcomes. Several changes have happened in the realm of cardiac surgery and several more are en route. At times, for want of evidence, maximal optimization may not take place and the patient may encounter unfavorable outcomes.. This review is an attempt to bring the focus of the members of the cardiac surgical team on the value of preoperative optimization of risks to improve the outcome. The cardiac surgical patients may broadly be divided into adults undergoing coronary artery bypass graft surgery, valve surgery and pediatric patients undergoing repair/palliation of congenital heart ailments. Optimization of risks appear to be different in each genre of patients. This review also brings less often discussed issues such as anemia, nutritional issues and endocrine problems. The review is an attempt to data on ameliorating modifiable risk factors and altering non modifiable ones.

Effect of levosimendan on prognosis in adult patients undergoing cardiac surgery: a meta-analysis of randomized controlled trials

Background

Small trials suggest that levosimendan is associated with a favorable outcome in patients undergoing cardiac surgery. However, recently published larger-scale trials did not provide evidence for a similar benefit from levosimendan. We performed a meta-analysis to assess the survival benefits of levosimendan in patients undergoing cardiac surgery and to investigate its effects in subgroups of patients with preoperative low-ejection fraction (EF).

Methods

We identified randomized clinical trials through 20 April 2017 that investigated levosimendan therapy versus control in patients undergoing cardiac surgery. Individual patient data from each study were compiled. Meta-analyses were performed for primary outcomes, secondary outcomes and serious adverse events, and subgroup analyses according to the preoperative EF of enrolled patients were also conducted. The risk of bias was assessed using the Cochrane risk-of-bias tool.

Results

Seventeen studies involving a total of 2756 patients were included. Levosimendan therapy was associated with a significant reduction in 30-day mortality (RR 0.67; 95% CI, 0.49 to 0.93; p = 0.02) and reduced the risk of death in single-center trials (RR 0.49; 95% CI, 0.30 to 0.79; p = 0.004) and in subgroup trials of inferior quality (RR 0.39; 95% CI, 0.17 to 0.92; p = 0.02); however, in multicenter and in high-quality subgroup-analysis trials, no significant difference in mortality was observed between patients who received levosimendan therapy and controls (p > 0.05). However, in high-quality subgroup trials, levosimendan therapy was associated with reduced mortality in patients in a preoperative low-EF subgroup (RR 0.58; 95% CI, 0.38 to 0.88; p = 0.01). Similarly, only patients in the preoperative low-EF subgroup benefited in terms of reduced risk of renal replacement therapy (RR 0.54; 95% CI, 0.34 to 0.85; p = 0.007). Furthermore, levosimendan therapy was associated with a significant reduction in intensive care unit (ICU) length of stay (MDR −17.19; 95% CI, −34.43 to −2.94; p = 0.02).

Conclusions

In patients undergoing cardiac surgery, the benefit of levosimendan in terms of survival was not shown in multicenter or in high-quality trials; however, levosimendan therapy was associated with reduced mortality in patients with preoperative ventricular systolic dysfunction.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1848-1) contains supplementary material, which is available to authorized users.

Impact of severe left ventricular dysfunction on in-hospital and mid-term outcomes of Chinese patients undergoing first isolated off-pump coronary artery bypass grafting

Background

Few studies focused on evaluating the impacts of preoperative severe left ventricular dysfunction on clinical outcomes of patients undergoing off-pump coronary artery bypass grafting surgery (OPCAB). This single center retrospective study aimed to evaluate the impacts of severe left ventricular dysfunction on in-hospital and mid-term clinical outcomes of Chinese patients undergoing first, scheduled, and isolated OPCAB surgery.

Methods

From January 2010 to December 2014, 2032 eligible patients were included in this study and were divided into 3 groups: a severe group (patients with preoperative left ventricular ejection fraction (LVEF) of ≤35%, n = 128), an impaired group (patients with preoperative LVEF of 36-50%, n = 680), and a normal group (patients with preoperative LVEF of >50%, n = 1224). In-hospital and follow-up clinical outcomes were investigated and compared.

Results

Patients in the severe group compared to the other 2 groups had higher in-hospital mortality and higher incidences of low cardiac output and prolonged ventilation. Kaplan-Meier curves showed a similar cumulative follow-up survival between the severe group and the impaired group (χ² = 1.980, Log-rank p = 0.159) and between the severe group and the normal group (χ² = 2.701, Log-rank p = 0.102). Multivariate Cox regression indicated that grouping was not a significant variable related to mid-term all-cause mortality. No significant difference was found in the rate of repeat revascularization between the severe group (2.4%) and the other 2 groups.

Conclusions

Patients with preoperative LVEF of ≤35% compared to preoperative LVEF of >35% increased the risk of in-hospital death and incidences of postoperative low cardiac output and prolonged ventilation, but shared similar mid-term all-cause mortality and repeat revascularization after OPCAB surgery.

The Predictive Value of Integrated Pulmonary Index after Off-Pump Coronary Artery Bypass Grafting: A Prospective Observational Study

Background

The early warning scores may increase the safety of perioperative period. The objective of this study was to assess the diagnostic and predictive role of Integrated Pulmonary Index (IPI) after off-pump coronary artery bypass grafting (OPCAB).

Materials and Methods

Forty adult patients undergoing elective OPCAB were enrolled into a single-center prospective observational study. We assessed respiratory function using IPI that includes oxygen saturation, end-tidal CO₂, respiratory rate, and pulse rate. In addition, we evaluated blood gas analyses and hemodynamics, including ECG, invasive arterial pressure, and cardiac index. The measurements were performed after transfer to the intensive care unit, after spontaneous breathing trial and at 2, 6, 12, and 18 h after extubation.

Results and Discussion

The value of IPI registered during respiratory support correlated weakly with cardiac index (rho = 0.4; p = 0.04) and ScvO₂ (rho = 0.4, p = 0.02). After extubation, IPI values decreased significantly, achieving a minimum by 18 h. The IPI value ≤9 at 6 h after extubation was a predictor of complicated early postoperative period (AUC = 0.71; p = 0.04) observed in 13 patients.

Conclusion

In off-pump coronary surgery, the IPI decreases significantly after tracheal extubation and may predict postoperative complications.

Impact of Patient and Lesion Complexity on Long-Term Outcomes Following Coronary Revascularization With New-Generation Drug-Eluting Stents

Long-term clinical outcomes of new-generation drug-eluting stents in complex anatomic and clinical settings are not well defined. This study assessed the impact of patient and lesion complexity on 2-year outcomes after coronary revascularization with ultrathin strut biodegradable-polymer (BP) sirolimus-eluting stents (SES) versus durable-polymer (DP) everolimus-eluting stents (EES). In a prespecified analysis of the BIOSCIENCE randomized trial (NCT01443104), complex patients (911 of 2,119; 43%) were defined by the presence of acute ST-elevation myocardial infarction (MI); left ventricular ejection fraction ≤30%; renal dysfunction; insulin-treated diabetes; treatment of ostial lesion, bypass graft, unprotected left main lesion; or 3-vessel intervention. The primary end point was target lesion failure (TLF), a composite of cardiac death, target vessel MI, and clinically indicated target lesion revascularization. At 2 years, complex compared with simple patients had a greater risk of TLF (14.5% vs 7.4%, risk ratio 2.05, 95% confidence interval 1.56 to 2.69; p <0.001). The difference was sustained beyond 1 year on landmark analysis. Complex patients had higher rates of the patient-oriented composite end point of death, any MI, or any revascularization (23% vs 14.4%; p <0.001) as well as definite stent thrombosis (1.6% vs 0.4%, p = 0.006). There were no differences in TLF and patient-oriented composite end point between the BP-SES versus DP-EES, consistently among simple and complex patients. In conclusion, patient and lesion complexity had a durable adverse impact on clinical outcomes throughout 2 years of follow-up in this all-comers randomized trial. Safety and efficacy of new-generation BP-SES and DP-EES were comparable, irrespective of complexity status.