Outcome of Patients With Low Ejection Fraction Undergoing Coronary Artery Bypass Grafting: Renal Function and Mortality After 3.8 Years

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.

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.

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.

Impact of chronic kidney disease in 29 893 patients undergoing transcatheter or surgical aortic valve replacement from the German Aortic Valve Registry

OBJECTIVES

Chronic kidney disease (CKD) is a key risk factor in patients undergoing transcatheter aortic valve implantation (TAVI) or surgical aortic valve replacement (SAVR). We analysed the impact of estimated glomerular filtration rate (eGFR) and CKD stages on their mid-term survival.

METHODS

Data from 29 893 patients enrolled in the German Aortic Valve registry from January 2011 to December 2015 receiving TAVI (n = 12 834) or SAVR (n = 17 059) at 88 sites were included. The impact of renal impairment, as measured by eGFR and CKD stages, was investigated. The primary end-point was 1-year cumulative all-cause mortality.

RESULTS

Higher CKD stages were significantly associated to lower in-hospital, 30-day- and 1-year survival rates. Both TAVI- and SAVR-treated patients in CKD 3a, 3b, 4 and 5 stages showed significant and gradually increasing HR values for 1-year all-cause mortality. The same trend persisted in multivariable analysis, although HR values for CKD 3a and 5 did not reach significance in TAVI patients, whereas CKD 4 + 5 did not reach statistical significance in SAVR. Likewise, eGFR as a continuous variable was a significant predictor for 1-year mortality, with the best cut-off points being 47.4 ml/min/1.73 m2 for TAVI and 59.8 ml/min/1.73 m2 for SAVR. Significant 8.6% and 9.0% increases in 1-year mortality were observed for every 5-ml reduction in eGFR for TAVI and SAVR, respectively.

CONCLUSIONS

CKD ≥3b and CKD ≥3a are the independent major risk factors for mortality in patients undergoing TAVI and SAVR, respectively. In the overall population of patients with severe aortic stenosis, an appropriate stratification based on CKD substage may contribute to a better selection of patients suitable for such therapies.

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.

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.

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.

Disability-free survival after coronary artery bypass grafting in women and men with heart failure

Objective

Heart failure (HF) impairs survival post coronary artery bypass grafting (CABG), but little is known about the postoperative quality of life (QoL) in patients with HF. We derived a patient-centred QoL surrogate and assessed the impact of different HF subtypes on this surrogate in the year post-CABG.

Methods

We surveyed 3112 cardiovascular patients to derive a patient-centred disability outcome and studied this outcome in a population-based cohort. We defined preserved ejection fraction as ≥50% and reduced ejection fraction as <50%. The primary outcome was disability, defined according to compiled patient-derived values. The secondary outcomes consisted of each individual component of disability, and death. The incidence of disability was calculated using cumulative incidence functions, with death as a competing risk. We identified predictors of disability using cause-specific hazard models.

Results

Patient-derived disability outcome consisted of stroke, nursing home admission and recurrent hospitalisations. When applied to 40 083 CABG patients (20.6% women), the incidence of disability was 5.4% while the incidence of death was 3.7% in the year post-CABG. Female sex was associated with an adjusted HR of 1.25 (95% CI 1.13 to 1.37) for disability. Women with HF with preserved ejection fraction had an adjusted HR of 1.73 (95% CI 1.52 to 1.98) for disability.

Conclusions

Disability was a more frequent complication than death in the year post-CABG. Women experienced higher burden of disability than men, and female sex and the presence of HF were important disability risk factors. Efforts should be dedicated to disability risk prediction to enable patient-centred operative decision-making and to developing sex-specific treatment strategies to improve outcomes.

Prevalence and Long-Term Survival After Coronary Artery Bypass Grafting in Women and Men With Heart Failure and Preserved Versus Reduced Ejection Fraction

BACKGROUND

Heart failure (HF) with reduced ejection fraction (rEF) is a widely regarded prognosticator after coronary artery bypass grafting. HF with preserved ejection fraction (pEF) accounts for up to half of all HF cases and is associated with considerable morbidity and mortality in hospitalized cohorts. However, HFpEF outcomes have not been elucidated in cardiac surgical patients. We investigated the prevalence and outcomes of HFpEF and HFrEF in women and men following coronary artery bypass grafting.

METHODS AND RESULTS

We conducted a retrospective cohort study in Ontario, Canada, between October 1, 2008, and March 31, 2015, using Cardiac Care Network and Canadian Institute of Health Information data. HF is captured through a validated population-based database of all Ontarians with physician-diagnosed HF. We defined pEF as ejection fraction ≥50% and rEF as ejection fraction <50%. The primary outcome was all-cause mortality. Analyses were stratified by sex. Mortality rates were calculated using Kaplan-Meier method. The relative hazard of death was assessed using multivariable Cox proportional hazard models. Of 40 083 patients (20.6% women), 55.5% had pEF without HF, 25.7% had rEF without HF, 6.9% had HFpEF, and 12.0% had HFrEF. Age-standardized HFpEF mortality rates at 4±2 years of follow-up were similar in women and men. HFrEF standardized HFpEF mortality rates were higher in women than men.

CONCLUSIONS

We found a higher prevalence and poorer prognosis of HFpEF in women. A history of HF was a more important prognosticator than ejection fraction. Preoperative screening and extended postoperative follow-up should be focused on women and men with HF rather than on rEF alone.

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.

Revascularization in Patients With Severe Left Ventricular Dysfunction: Is the Assessment of Viability Still Viable?

Myocardial viability assessment is typically reserved for patients with coronary artery disease and significant left ventricular dysfunction. In this setting, there is myocardial adaptation to an altered physiological state that is potentially reversible. Imaging can characterize different parameters of cardiac function; however, despite previously published appraisals of different imaging modalities, there is still uncertainty regarding the role of these tests in clinical practice. The purpose of this review is to reflect on the physiological basis of myocardial viability, discuss the imaging tests available that characterize myocardial viability, and summarize the current published reports on the use of these tests in clinical practice.

Reduced Right Ventricular Function Predicts Long-Term Cardiac Re-Hospitalization after Cardiac Surgery

Background

The significance of right ventricular ejection fraction (RVEF), independent of left ventricular ejection fraction (LVEF), following isolated coronary artery bypass grafting (CABG) and valve procedures remains unknown. The aim of this study is to examine the significance of abnormal RVEF by cardiac magnetic resonance (CMR), independent of LVEF in predicting outcomes of patients undergoing isolated CABG and valve surgery.

Methods

From 2007 to 2009, 109 consecutive patients (mean age, 66 years; 38% female) were referred for pre-operative CMR. Abnormal RVEF and LVEF were considered <35% and <45%, respectively. Elective primary procedures include CABG (56%) and valve (44%). Thirty-day outcomes were perioperative complications, length of stay, cardiac re-hospitalizations and early mortaility; long-term (> 30 days) outcomes included, cardiac re-hospitalization, worsening congestive heart failure and mortality. Mean clinical follow up was 14 months.

Findings

Forty-eight patients had reduced RVEF (mean 25%) and 61 patients had normal RVEF (mean 50%) (p<0.001). Fifty-four patients had reduced LVEF (mean 30%) and 55 patients had normal LVEF (mean 59%) (p<0.001). Patients with reduced RVEF had a higher incidence of long-term cardiac re-hospitalization vs. patients with normal RVEF (31% vs.13%, p<0.05). Abnormal RVEF was a predictor for long-term cardiac re-hospitalization (HR 3.01 [CI 1.5-7.9], p<0.03). Reduced LVEF did not influence long-term cardiac re-hospitalization.

Conclusion

Abnormal RVEF is a stronger predictor for long-term cardiac re-hospitalization than abnormal LVEF in patients undergoing isolated CABG and valve procedures.

Coronary artery bypass grafting in patients 50 years or younger: a Swedish nationwide cohort study

BACKGROUND

There are limited data regarding long-term results after coronary artery bypass grafting (CABG) in young adults. We performed a nationwide population-based cohort study to analyze long-term survival, major adverse cardiovascular events, and factors associated with elevated risk in young adults undergoing CABG.

METHODS AND RESULTS

We included all adult patients ≤50 years of age who underwent primary isolated CABG in Sweden between 1997 and 2013 from the Swedish Web System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies (SWEDEHEART) register. Patient data were linked from national Swedish health data registers to create a study database. We identified 4086 young adults with a mean age of 46 years and 18% women. During a median follow-up time of 10.9 years (interquartile range, 6.4-14.1) 490 (12%) patients died. Survival at 5, 10, and 15 years was 96% (95% CI, 95-96), 90% (95% CI, 89-91), and 82% (95%CI, 80-83), respectively, which was significantly better in comparison with patients aged 51 to 70 years and >70 years who underwent CABG during the same period. The cumulative incidence of death or a major adverse cardiovascular event during 17 years after CABG was mainly driven by myocardial infarction or the need for repeat revascularization. The most important risk factors for all-cause mortality were chronic kidney disease, reduced left ventricular ejection fraction, peripheral vascular disease, or chronic obstructive pulmonary disease.

CONCLUSIONS

Long-term survival and freedom from major cardiovascular events after CABG was better in young adults than in older patients. Factors significantly associated with an elevated long-term risk of death or adverse outcome were similar to well-known risk factors for older age groups following CABG.

CLINICAL TRIAL REGISTRATION

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

Outcomes of off-pump coronary bypass grafting with the bilateral internal thoracic artery for left ventricular dysfunction

This study evaluated the outcomes of off-pump coronary artery bypass surgery (OPCAB) with severe left ventricular dysfunction using composite bilateral internal thoracic artery grafting. From January 2001 to December 2008, 1,842 patients underwent primary isolated OPCAB with composite bilateral internal thoracic artery grafting. A total of 131 of these patients were diagnosed with a severely depressed preoperative left ventricle ejection fraction (LVEF) (≤ 0.35). These patient outcomes were compared with the outcomes of 830 patients that had mildly or moderately depressed LVEF (0.36 to 0.59) and 881 patients with normal LVEF (>0.6). The early mortality for patients with severe LVEF was 2.3%. The 3-yr and 7-yr survival rate for patients with severe LV dysfunction was 86.0% and 82.8%, respectively. Multivariate analysis showed that severe LV dysfunction EF increased the risk of all-cause death (P=0.012; hazard ratio [HR],2.14; 95% confidence interval [CI],1.19-3.88) and the risk of cardiac-related death (P=0.008; HR,3.38; 95% CI, 1.37-8.341). The study identified positive surgical outcomes of OPCAB, although severe LVEF was associated with two-fold increase in mortality risk compared with patients who had normal LVEF.

Coronary artery bypass grafting in patients with left ventricular dysfunction: predictors of long-term survival and impact of surgical strategies

BACKGROUND

In the surgical management of ischemic cardiomyopathy, factors associated with long-term prognosis after coronary artery bypass grafting (CABG) in patients with severe left ventricular (LV) dysfunction are poorly understood. This study aimed to determine predictors of clinical outcomes in patients with severe LV dysfunction undergoing CABG.

METHODS

Out of 6084 patients who underwent CABG between 1997 and 2011, 476 patients (aged 62.6 ± 9.3 years, 100 females) were identified as having severe LV dysfunction (ejection fraction ≤ 35%), preoperatively. All-cause mortality and adverse cardiac events (myocardial infarction, repeat revascularization, stroke and hospitalization due to cardiovascular causes) were evaluated during a median follow-up period of 55.2 months (inter-quartile range: 26.4-94.8 months).

RESULTS

During the follow-up, 187 patients (39.3%) died and 126 cardiac events occurred in 104 patients (21.8%). Five-year survival and event-free survival rates were 72.1 ± 2.2% and 61.3 ± 2.4%, respectively. On Cox-regression analysis, old age (P < 0.001), recent MI (P < 0.001), history of coronary stenting (P = 0.023), decreased glomerular filtration rate (P < 0.001), and presence of mitral regurgitation (≥moderate) (P = 0.012) or LV wall thinning (P = 0.007) emerged as significant and independent predictors of death. After adjustment for important covariates affecting outcomes, none of the pump strategy (off-pump vs. on-pump), concomitant mitral surgery or surgical ventricular reconstruction (SVR) affected survival or event-free survival (P = 0.082 to >0.99).

CONCLUSIONS

Long-term survival following CABG in patients with severe LV dysfunction was affected by age, renal function, recent MI, prior coronary stenting, and presence of mitral regurgitation or LV wall thinning. Neither concomitant mitral surgery nor SVR, however, had significant influence on clinical outcomes.

Noninvasive assessment myocardial viability: current status and future directions

Observations of reversibility of cardiac contractile dysfunction in patients with coronary artery disease and ischemia were first made more than 40 years ago. Since that time a wealth of basic science and clinical data has been gathered exploring the mechanisms of this phenomenon of myocardial viability and relevance to clinical care of patients. Advances in cardiac imaging techniques have contributed greatly to knowledge in the area, first with thallium-201 imaging, then later with Tc-99m-based tracers for SPECT imaging and metabolic tracers used in conjunction with positron emission tomography (PET), most commonly F-18 FDG in conjunction with blood flow imaging with N-13 ammonia or Rb-82 Cl. In parallel, stress echocardiography has made great progress also. Over time observational studies in patients using these techniques accumulated and were later summarized in several meta-analyses. More recently, cardiac magnetic resonance imaging (CMR) has contributed further information in combination with either late gadolinium enhancement imaging or dobutamine stress. This review discusses the tracer and CMR imaging techniques, the pooled observational data, the results of clinical trials, and ongoing investigation in the field. It also examines some of the current challenges and issues for researchers and explores the emerging potential of combined PET/CMR imaging for myocardial viability.

Renal dysfunction and long-term risk of heart failure after coronary artery bypass grafting

BACKGROUND

Renal dysfunction is associated with increased long-term mortality and incidence of myocardial infarction after coronary artery bypass grafting (CABG). The aim was to investigate the relationship between renal dysfunction and long-term risk of heart failure after CABG.

METHODS

All 29,602 patients who underwent primary isolated CABG from 2000 through 2008 in Sweden, with no myocardial infarction within 14 days before surgery, no prior hospitalization for heart failure, and alive 30 days postoperatively, were included from the Swedish Web-system for Enhancement and Development of Evidence-based care in Heart disease Evaluated According to Recommended Therapies registry. Glomerular filtration rates (eGFR) were estimated using the Modification of Diet in Renal Disease equation. Hazard ratios with 95% CIs were calculated for first hospitalization for heart failure.

RESULTS

Mean age in the study population was 67 years, and 20% had eGFR <60 mL/min per 1.73 m(2). During a mean follow-up of 4.5 years, there were 1,690 (5.7%) cases of heart failure. Adjusted hazard ratios with 95% CI for heart failure in patients with eGFR 45 to 60, 30 to 45, and 15 to 30 mL/min per 1.73 m(2) were 1.53 (1.36-1.72), 2.08 (1.76-2.45), and 2.14 (1.52-3.01), respectively, compared with patients with eGFR >60 mL/min per 1.73 m(2).

CONCLUSIONS

Renal dysfunction is a long-term predictor of new-onset heart failure after primary isolated CABG.

Long-term outcomes after off-pump coronary artery bypass grafting in left ventricular dysfunction

PURPOSE

We assessed the long-term clinical, angiographic, and echocardiographic outcomes of patients with left ventricular dysfunction (ejection fraction ≤40%) who underwent isolated off-pump coronary artery bypass grafting.

METHODS

One hundred sixty one patients were included. Mean age was 67.2 ± 11.4 years, and 20 patients (12.4%) were female. Eighty-eight patients (54.7%) were New York Heart Association functional class 3 or 4. Early postoperative and follow-up angiography and echocardiography findings were analyzed, and mid-term survival rates (mean follow-up 40.7 ± 25.6 months) were calculated.

RESULTS

Mean number of distal anastomoses was 4.4 ± 1.3. Bilateral internal thoracic artery grafts were used in 84.5% of patients. Operative mortality was 2.5%. Early patency rate of anastomoses was 98.3%. Early postoperative ejection fraction improved from 33.1 ± 5.6% preoperatively to 36.9 ± 9.5% (p <0.001). Seven-year survival rate was 73.9 ± 5.3%, and freedom from cardiac events rate was 68.5 ± 5.2%. One-year patency rate of anastomoses was 85.8%. Follow-up ejection fraction was 39.1 ± 10.7% (p <0.001).

CONCLUSIONS

Early and long-term outcomes of off-pump coronary artery bypass grafting in patients with left ventricular dysfunction were favorable, including early postoperative and follow-up patency rates of anastomoses and echocardiographic recovery of ejection fraction.

Early risk of mortality after coronary artery revascularization in patients with left ventricular dysfunction and potential role of the wearable cardioverter defibrillator

BACKGROUND

Implantation of implantable cardioverter defibrillator for prevention of sudden cardiac death is deferred for 90 days after coronary revascularization, but mortality may be highest early after cardiac procedures in patients with ventricular dysfunction. We determined mortality risk in postrevascularization patients with left ventricular ejection fraction ≤35% and compared survival with those discharged with a wearable cardioverter defibrillator (WCD).

METHODS AND RESULTS

Hospital survivors after surgical (coronary artery bypass graft surgery) or percutaneous (percutaneous coronary intervention [PCI]) revascularization with left ventricular ejection fraction ≤35% were included from Cleveland Clinic and national WCD registries. Kaplan-Meier, Cox proportional hazards, propensity score-matched survival, and hazard function analyses were performed. Early mortality hazard was higher among 4149 patients discharged without a defibrillator compared with 809 with WCDs (90-day mortality post-coronary artery bypass graft surgery 7% versus 3%, P=0.03; post-PCI 10% versus 2%, P<0.0001). WCD use was associated with adjusted lower risks of long-term mortality in the total cohort (39%, P<0.0001) and both post-coronary artery bypass graft surgery (38%, P=0.048) and post-PCI (57%, P<0.0001) cohorts (mean follow-up, 3.2 years). In propensity-matched analyses, WCD use remained associated with lower mortality (58% post-coronary artery bypass graft surgery, P=0.002; 67% post-PCI, P<0.0001). Mortality differences were not attributable solely to therapies for ventricular arrhythmia. Only 1.3% of the WCD group had a documented appropriate therapy.

CONCLUSIONS

Patients with left ventricular ejection fraction ≤35% have higher early compared to late mortality after coronary revascularization, particularly after PCI. As early hazard seemed less marked in WCD users, prospective studies in this high-risk population are indicated to confirm whether WCD use as a bridge to left ventricular ejection fraction improvement or implantable cardioverter defibrillator implantation can improve outcomes after coronary revascularization.

Predictive accuracy of SYNTAX score for predicting long-term outcomes of unprotected left main coronary artery revascularization

The American College of Cardiology/American Heart Association recently updated recommendations for percutaneous coronary intervention (PCI) of unprotected left main coronary artery (ULMCA) disease from class III to II(b) according to the results of the SYNergy between percutaneous coronary intervention with TAXus and cardiac surgery (SYNTAX) trial. The SYNTAX score is an angiographic tool using solely the coronary anatomy. We studied the effect of co-morbidities (Parsonnet's score) on the ability of the SYNTAX score to predict long-term outcomes in patients with ULMCA disease treated by revascularization. A total of 328 patients underwent revascularization of ULMCA from April 2003 to February 2007. Of the 328 patients, 120 underwent PCI (median follow-up 973 days) and 208 underwent coronary artery bypass grafting (CABG) (median follow-up 1,298 days). The ability of the SYNTAX score to predict outcomes was assessed using the Cox proportional hazards model. The outcomes between the PCI and CABG groups were compared by propensity analysis. The median SYNTAX score was 26 in the PCI and 28 in the CABG group (p = 0.5). In the PCI group, greater quartiles were associated with worse survival (62.1% at SYNTAX score of ≥36 vs 82.4% at SYNTAX score of <36, p = 0.03) and all-cause mortality, myocardial infarction, cerebrovascular events, and target vessel revascularization-free (MACCE) survival (47.7%, SYNTAX score ≥20 vs 76.6%, SYNTAX score <20, p = 0.02). Using the Parsonnet score as a covariate, the SYNTAX score continued to be an independent predictor of MACCE and demonstrated a trend toward predicting mortality in the PCI group. In contrast, the SYNTAX score did not predict the outcomes for the CABG group. No difference was found in mortality between the PCI and CABG groups for ULMCA disease, regardless of coronary complexity; although greater SYNTAX scores were associated with increased MACCE rates with PCI compared to CABG. Both the coronary anatomy (SYNTAX score) and co-morbidities (Parsonnet's score) predicted long-term outcomes for PCI of ULMCA disease. In contrast, the SYNTAX score did not predict the outcomes after CABG. In conclusion, the ideal scoring system to guide an appropriate revascularization decision for ULMCA disease should take into account both the coronary anatomy and the co-morbidities.

Off-pump Coronary Bypass Surgery in Patients with Low Ejection Fraction

Objective

Long-term survival after off-pump surgery in patients with low ejection fraction was investigated.

Methods

Three hundred forty-six patients with ejection fraction 30% or less with isolated off-pump coronary artery bypass surgery (OPCAB) were compared with a propensity matched historical group operated on-pump (ONCAB) and with data from literature after percutaneous coronary intervention and OPCAB surgery.

Results

The lower invasiveness of OPCAB contributed to a significantly better 30-day survival, shorter postoperative length of stay, and fewer in-hospital complications. Incomplete revascularization of the posterior and lateral territories of the heart correlated with higher 1-year mortality. The probability of survival for 8 years after OPCAB was 50.1% (n = 76) versus 49.7% (n = 82) for ONCAB without comparable data from literature for OPCAB or percutaneous coronary intervention in these high-risk patients.

Conclusions

OPCAB surgery in patients with low ejection fraction is a viable alternative but so far without demonstrable long-term survival advantage to ONCAB.

Prognostic value of the Syntax score in patients undergoing coronary artery bypass grafting for three-vessel coronary artery disease

BACKGROUND

The Syntax score prognostic value has recently been highlighted in patients undergoing percutaneous coronary intervention (PCI) for multivessel coronary artery disease (CAD), however its prognostic value in patients undergoing coronary artery bypass grafting (CABG) for multivessel CAD is still unknown. The aim of this study was to evaluate the prognostic value of the Syntax score in patients undergoing CABG for 3-vessel CAD.

METHODS

A cohort of 320 consecutive patients with multivessel (3-vessel) CAD who were subjected for CABG were included in this study and divided into tertiles according to the Syntax score (<24.5, 24.5-34, and >34). During the 1-year follow-up, cardiovascular events including death, myocardial infarction (MI), and stroke were systematically indexed. The primary end point was the composite criteria death/MI/stroke.

RESULTS

The Syntax score ranged from 11-74 with a mean of 31.2 +/- 12.6 and a median of 28.5 [22-38]. Baseline clinical characteristics were similar among the tertiles. No statistical difference was found for the composite criteria death/MI/stroke: 9.4% versus 7.5% versus 10.4% in the groups with a Syntax score <24.5, 24.5-34, and >34, respectively (P = 0.754).

CONCLUSION

Unlike for PCI, the Syntax score has a poor prognostic value for severe cardiovascular events in patients undergoing CABG for 3-vessel CAD. Other risk scores should be used to predict the outcome of this population.

Comorbidity in patients undergoing coronary artery bypass graft surgery: impact on outcome and implications for cardiac rehabilitation

The increasing comorbid disease burden among patients undergoing coronary artery bypass graft surgery (CABG) and the improved operative survival are expanding the number of post-CABG patients living with prognostically significant comorbidities. In a large contemporary database, 29.9% of the patients receiving isolated CABG had diabetes mellitus, 16% peripheral vascular disease, 18.6% chronic obstructive pulmonary disease, and 27.5% renal dysfunction. Patients with comorbidity are more likely to be old and often female, may have special care-requirements early after discharge, and are at increased risk for adverse outcomes. Contemporary available evidence indicates that older individuals, women, and patients with comorbidities are significantly less likely to receive cardiac rehabilitation. In addition, compliance with proven atherosclerosis risk reduction strategies for CABG patients is suboptimal. In this article we will review the impact of comorbidity on short-term and long-term outcome after CABG and their implications for cardiac rehabilitation.

Totally epicardial cardiac resynchronization therapy system implantation in patients with heart failure undergoing CABG

BACKGROUND

Systolic dyssynchrony is present in a considerable number of patients with heart failure (HF) undergoing coronary artery bypass grafting (CABG). Surgical revascularization offers an optimal setting for totally epicardial cardiac resynchronization therapy (CRT) system implantation.

AIM

To assess the efficacy of totally epicardial CRT implantation during CABG, in patients with HF.

METHODS

Twenty three patients with HF and dyssynchrony underwent totally epicardial CRT system implantation during CABG. This randomised, single-blind, cross-over study compared clinical and echocardiographic parameters during two periods: 3 months of active CRT (CRT+) and 3 months of inactive CRT (CRT-) pacing.

RESULTS

Twenty two patients underwent randomisation and completed both study periods. In the CRT+ group more patients improved by two NYHA classes (p=0.028), had a longer 6-minute walk test distance (p=0.047) and better quality of life (p=0.003) compared with the CRT- group. Echocardiography revealed an improved LV ejection fraction (p<0.001), smaller LV end-systolic volume (p=0.04), reduced mitral regurgitation (p=0.026) and improved LV synchrony in the CRT+ group compared with the CRT- group.

CONCLUSION

CRT delivered by a totally epicardial system implanted during CABG is associated with additional improvement of clinical and echocardiographic parameters in patients with HF and systolic dyssynchrony.

Long-term survival and functional recovery after isolated coronary artery bypass grafting in patients with severe left ventricular dysfunction

OBJECTIVE

Coronary artery bypass grafting (CABG) in patients with left ventricular dysfunction has been considered to be a challenging operation. We assessed the early angiographic and long-term clinical and functional outcomes of patients with poor left ventricular function who underwent isolated CABG.

METHODS

We retrospectively reviewed the records of 78 patients with a poor left ventricular ejection fraction (35% or less) who underwent isolated CABG between January 1991 and November 2006. The mean age of the patients was 66.1+/-9.4 years, and their mean New York Heart Association functional class was 3.1+/-0.8. Their mean end-diastolic left ventricular diameter was 57.4+/-8.1 mm, and their mean grade of mitral regurgitation was 0.7+/-1.0. Early postoperative angiograms were performed at 32.5+/-33.5 days after the operation. Interval echocardiographic data were analyzed, and the long-term survival rate was evaluated.

RESULTS

The average number of distal anastomoses per patient was 3.2 +/-1.1. The operative mortality rate was 7.7%. Stroke occurred in 1.3% of patients. The overall patency rates for arterial and venous grafts were 100% and 97.2%, respectively. The left ventricular ejection fraction significantly improved from 28.2%+/-5.1% to 34.4%+/-8.4%. Both the end-diastolic and end-systolic left ventricular dimensions significantly decreased from 57.4+/-8.1 to 55.1+/-8.8 mm and from 47.4+/-8.4 to 45.1+/-9.7, re spectively. The actuarial patient survival rate at 10 years was 73.1%.

CONCLUSION

CABG in patients with left ventricular dysfunction was effective, with favorable early graft patency rates. The long-term outcome was also acceptable, with echocardiographic functional recovery.

Factors Affecting Survival after Endovascular Aneurysm Repair: Results from a Population Based Audit

OBJECTIVES

To determine the effect of pre-operative factors on mid-term survival of patients enrolled in an Australian audit of endovascular aneurysm repair (EVAR).

DESIGN

Prospective longitudinal national register (audit) of patients undergoing EVAR.

METHODS

961 individuals who had elective or semi-urgent EVAR of abdominal aortic aneurysms were enrolled in the audit between November 1999 and May 2001. Data was contributed by 81 surgeons from 64 hospitals. Kaplan-Meier survival analysis was used to determine survival rates and factors significantly influencing survival. Parametric survival analysis with log-exponential distribution was used to estimate expected 3 and 5 year survival for different ages, ASA, creatinine and aneurysm sizes.

RESULTS

Overall survival was 93% at 1 year, 80% at 3 years and 67% at five years. Survival rates were found to be statistically associated with ASA, age, aneurysm size and creatinine levels. ASA has the largest effect. Five year survival rates for aneurysms >or=65 mm and <55 mm were 54% and 76% respectively. Pre-operative creatinine levels >or=160 micromol/L lowered the survival rate from 71% to 40%.

CONCLUSIONS

Survival for EVAR patients is strongly correlated with a number of pre-operative factors. This survival analysis provides a useful decision-making tool for surgeons particularly for individuals with smaller aneurysms.