Coronary artery bypass grafting in patients with low ejection fraction

Outcome of cardiac surgery in patients with low preoperative ejection fraction

Background

In patients undergoing cardiac surgery, a reduced preoperative left ventricular ejection fraction (LVEF) is common and is associated with a worse outcome. Available outcome data for these patients address specific surgical procedures, mainly coronary artery bypass graft (CABG). Aim of our study was to investigate perioperative outcome of surgery on patients with low pre-operative LVEF undergoing a broad range of cardiac surgical procedures.

Methods

Data from patients with pre-operative LVEF ≤40 % undergoing cardiac surgery at a university hospital were reviewed and analyzed. A subgroup analysis on patients with pre-operative LVEF ≤30 % was also performed.

Results

A total of 7313 patients underwent cardiac surgery during the study period. Out of these, 781 patients (11 %) had a pre-operative LVEF ≤40 % and were included in the analysis. Mean pre-operative LVEF was 33.9 ± 6.1 % and in 290 patients (37 %) LVEF was ≤30 %. The most frequently performed operation was CABG (31 % of procedures), followed by mitral valve surgery (22 %) and aortic valve surgery (19 %). Overall perioperative mortality was 5.6 %. Mitral valve surgery was more frequent among patients who did not survive, while survivors underwent more frequently CABG. Post-operative myocardial infarction occurred in 19 (2.4 %) of patients, low cardiac output syndrome in 271 (35 %). Acute kidney injury occurred in 195 (25 %) of patients. Duration of mechanical ventilation was 18 (12–48) hours. Incidence of complications was higher in patients with LVEF ≤30 %. Stepwise multivariate analysis identified chronic obstructive pulmonary disease, pre-operative insertion of intra-aortic balloon pump, and pre-operative need for inotropes as independent predictors of mortality among patients with LVEF ≤40 %.

Conclusions

We confirmed that patients with low pre-operative LVEF undergoing cardiac surgery are at higher risk of post-operative complications. Cardiac surgery can be performed with acceptable mortality rates; however, mitral valve surgery, was found to be associated with higher mortality rates in this population. Accurate selection of patients, risk/benefit evaluation, and planning of surgical and anesthesiological management are mandatory to improve outcome.

Electronic supplementary material

The online version of this article (doi:10.1186/s12871-016-0271-5) contains supplementary material, which is available to authorized users.

Coronary-Artery Bypass Surgery in Patients with Ischemic Cardiomyopathy

BACKGROUND

The survival benefit of a strategy of coronary-artery bypass grafting (CABG) added to guideline-directed medical therapy, as compared with medical therapy alone, in patients with coronary artery disease, heart failure, and severe left ventricular systolic dysfunction remains unclear.

METHODS

From July 2002 to May 2007, a total of 1212 patients with an ejection fraction of 35% or less and coronary artery disease amenable to CABG were randomly assigned to undergo CABG plus medical therapy (CABG group, 610 patients) or medical therapy alone (medical-therapy group, 602 patients). The primary outcome was death from any cause. Major secondary outcomes included death from cardiovascular causes and death from any cause or hospitalization for cardiovascular causes. The median duration of follow-up, including the current extended-follow-up study, was 9.8 years.

RESULTS

A primary outcome event occurred in 359 patients (58.9%) in the CABG group and in 398 patients (66.1%) in the medical-therapy group (hazard ratio with CABG vs. medical therapy, 0.84; 95% confidence interval [CI], 0.73 to 0.97; P=0.02 by log-rank test). A total of 247 patients (40.5%) in the CABG group and 297 patients (49.3%) in the medical-therapy group died from cardiovascular causes (hazard ratio, 0.79; 95% CI, 0.66 to 0.93; P=0.006 by log-rank test). Death from any cause or hospitalization for cardiovascular causes occurred in 467 patients (76.6%) in the CABG group and in 524 patients (87.0%) in the medical-therapy group (hazard ratio, 0.72; 95% CI, 0.64 to 0.82; P<0.001 by log-rank test).

CONCLUSIONS

In a cohort of patients with ischemic cardiomyopathy, the rates of death from any cause, death from cardiovascular causes, and death from any cause or hospitalization for cardiovascular causes were significantly lower over 10 years among patients who underwent CABG in addition to receiving medical therapy than among those who received medical therapy alone. (Funded by the National Institutes of Health; STICH [and STICHES] ClinicalTrials.gov number, NCT00023595.).

Ten Years Experiences With Preoperative Evaluation Clinic for Day Admission Cardiac and Major Vascular Surgical Patients: Model for "Perioperative Anesthesia and Surgical Home"

Admission on the day of surgery for elective cardiac and noncardiac surgery is the prevalent practice in North America and Canada. This approach realizes medical, psychological and logistical benefits, and its success is predicated on an effective outpatient preoperative evaluation. The establishment of a highly functional preoperative clinic with a comprehensive set up and efficient logistical pathways is invaluable. This notion in recent years has included the entire perioperative period, and the concept of a perioperative anesthesia/surgical home (PASH) is gaining popularity. The anesthesiologists as perioperative physicians can organize and lead the entire process from the preoperative evaluation, through the hosptial discharge. The functions of the PASH include preoperative optimization of medical conditions and psychological preparation of the patients and their support system; the care in the operating room and intensive care unit; pain management; respiratory therapy; cardiac rehabilitation; and specialized nutrition. Along with oversight of the medical issues, the preoperative visit is an opportune time for counseling, clarification of expectations and discussion of research, as well as for utilization of various informatics systems to consolidate the pertinent information and distribute it to relevant health care providers. We review the scientific foundation and practical applications of a preoperative visit and share our experience with the development of the preoperative evaluation clinic, designed specifically for cardiac and major vascular patients scheduled for day admission surgery. The ultimate goal of preoperative evaluation clinic is to ensure a safe, efficient, and cost-effective perioperative care for patients undergoing a complex type of surgery.

Influence of Baseline Characteristics, Operative Conduct, and Postoperative Course on 30-Day Outcomes of Coronary Artery Bypass Grafting Among Patients With Left Ventricular Dysfunction: Results From the Surgical Treatment for Ischemic Heart Failure (STICH) Trial

BACKGROUND

Patients with severe left ventricular dysfunction, ischemic heart failure, and coronary artery disease suitable for coronary artery bypass grafting (CABG) are at higher risk for surgical morbidity and mortality. Paradoxically, those patients with the most severe coronary artery disease and ventricular dysfunction who derive the greatest clinical benefit from CABG are also at the greatest operative risk, which makes decision making regarding whether to proceed to surgery difficult in such patients. To better inform such decision making, we analyzed the Surgical Treatment for Ischemic Heart Failure (STICH) CABG population for detailed information on perioperative risk and outcomes.

METHODS AND RESULTS

In both STICH trials (hypotheses), 2136 patients with a left ventricular ejection fraction of ≤35% and coronary artery disease were allocated to medical therapy, CABG plus medical therapy, or CABG with surgical ventricular reconstruction. Relationships of baseline characteristics and operative conduct with morbidity and mortality at 30 days were evaluated. There were a total of 1460 patients randomized to and receiving surgery, and 346 (≈25%) of these high-risk patients developed a severe complication within 30 days. Worsening renal insufficiency, cardiac arrest with cardiopulmonary resuscitation, and ventricular arrhythmias were the most frequent complications and those most commonly associated with death. Mortality at 30 days was 5.1% and was generally preceded by a serious complication (65 of 74 deaths). Left ventricular size, renal dysfunction, advanced age, and atrial fibrillation/flutter were significant preoperative predictors of mortality within 30 days. Cardiopulmonary bypass time was the only independent surgical variable predictive of 30-day mortality.

CONCLUSIONS

CABG can be performed with relatively low 30-day mortality in patients with left ventricular dysfunction. Serious postoperative complications occurred in nearly 1 in 4 patients and were associated with mortality.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00023595.

Peri-operative Levosimendan in Patients Undergoing Cardiac Surgery: An Overview of the Evidence

Levosimendan, a calcium sensitiser, has recently emerged as a valuable agent in the peri-operative management of cardiac surgery patients. Levosimendan is a calcium-sensitising ionodilator. By binding to cardiac troponin C and reducing its calcium-binding co-efficient, it enhances myofilament responsiveness to calcium and thus enhances myocardial contractility without increasing oxygen demand. Current evidence suggests that levosimendan enhances cardiac function after cardiopulmonary bypass in patients with both normal and reduced left ventricular function. In addition to being used as post-operative rescue therapy for low cardiac output syndrome, a pre-operative levosimendan infusion in high risk patients with poor cardiac function may reduce inotropic requirements, the need for mechanical support, the duration of intensive care admissions as well as post-operative mortality. Indeed, it is these higher-risk patients who may experience a greater degree of benefit. Larger, multicentre randomised trials in cardiac surgery will help to elucidate the full potential of this agent.

Extent of coronary and myocardial disease and benefit from surgical revascularization in ischemic LV dysfunction [Corrected]

BACKGROUND

Patients with ischemic left ventricular dysfunction have higher operative risk with coronary artery bypass graft surgery (CABG). However, those whose early risk is surpassed by subsequent survival benefit have not been identified.

OBJECTIVES

This study sought to examine the impact of anatomic variables associated with poor prognosis on the effect of CABG in ischemic cardiomyopathy.

METHODS

All 1,212 patients in the STICH (Surgical Treatment of IsChemic Heart failure) surgical revascularization trial were included. Patients had coronary artery disease (CAD) and ejection fraction (EF) of ≤35% and were randomized to receive CABG plus medical therapy or optimal medical therapy (OMT) alone. This study focused on 3 prognostic factors: presence of 3-vessel CAD, EF below the median (27%), and end-systolic volume index (ESVI) above the median (79 ml/m(2)). Patients were categorized as having 0 to 1 or 2 to 3 of these factors.

RESULTS

Patients with 2 to 3 prognostic factors (n = 636) had reduced mortality with CABG compared with those who received OMT (hazard ratio [HR]: 0.71; 95% confidence interval [CI]: 0.56 to 0.89; p = 0.004); CABG had no such effect in patients with 0 to 1 factor (HR: 1.08; 95% CI: 0.81 to 1.44; p = 0.591). There was a significant interaction between the number of factors and the effect of CABG on mortality (p = 0.022). Although 30-day risk with CABG was higher, a net beneficial effect of CABG relative to OMT was observed at >2 years in patients with 2 to 3 factors (HR: 0.53; 95% CI: 0.37 to 0.75; p<0.001) but not in those with 0 to 1 factor (HR: 0.88; 95% CI: 0.59 to 1.31; p = 0.535).

CONCLUSIONS

Patients with more advanced ischemic cardiomyopathy receive greater benefit from CABG. This supports the indication for surgical revascularization in patients with more extensive CAD and worse myocardial dysfunction and remodeling. (Comparison of Surgical and Medical Treatment for Congestive Heart Failure and Coronary Artery Disease [STICH]; NCT00023595).

Improvement of ejection fraction after coronary artery bypass grafting surgery in patients with impaired left ventricular function

OBJECTIVES

The present study evaluates our experience with aorto-coronary bypass grafting in patients with severe dysfunction of left ventricle (LV) and low ejection fraction-EF(<35%). Revascularization of myocardium in this settings remains contraversial because of concerns over morbidity, mortality and quality of life.

MATERIAL AND METHODES

Forty patients with severe coronary artery disease and dysfunction of LV (low ejection fraction <35%) underwent coronary artery bypass grafting in period of 3 years. Preoperative diagnostic of 40 patients was consisted of anamnesis, clinical exam, non-invasive methods EHO, MR and invasive diagnostic methods-cateterization. The major indication for surgery was severe anginal pain, heart failure symptoms and low ejection fraction. Internal mammary artery was used in all operated patients.

RESULTS

Average age of patients who have been operated was 59,8. In the present study, 81,3% were male and 18,8% female. We found one-vessel disease present in 2,5% (1/40) of patients, two -vessel disease in 40% (16/40), three-vessel disease in 42,5% (17/40) and four -vessel disease in 15% (6/40) of patients. One bypass grafting we implanted in 2,5% patients, two bypasses in 42,5%, three bypasses in 45 5%, and four bypasses in 10% of patients. Left ventricular ejection fraction assessed preoperativly was 18%-27% and postoperatively was improved to 31, 08% in period of 30 days.

CONCLUSION

In patients with left ventricular dysfunction, coronary artery bypass grafting can be performed safely with improvement in quality of life and in left ventricular ejection fraction.

Coronary surgery in patients with low ejection fraction: mid-term results

BACKGROUND

The aim of this study was to investigate the effect of preoperative low ejection fraction (≤30%) on postoperative morbidity and mortality in patients undergoing isolated on-pump coronary artery bypass grafting. We also investigated the effect of pre- and perioperative factors on survival.

METHODS

Between January 2002 and December 2009, 103 (6.2%) patients with an ejection fraction ≤30% and 1554 (93.8%) with an ejection fraction >30% underwent coronary artery bypass grafting.

RESULTS

In multivariate logistic regression analysis, cardiopulmonary bypass time, operation time, prolonged inotropic support, and intensive care unit stay were independent predictors of mortality in patients with low ejection fraction. Intensive care unit and hospital stays were significantly longer in these patients, and the postoperative mortality rate was significantly higher. Advanced age (≥70 years) influenced mortality during the follow-up of patients with low ejection fraction. Midterm survival was significantly reduced in patients with ejection fraction ≤30%. Smoking, prolonged inotropic support, and prolonged ventilatory support were independent predictors of midterm survival in patients with ejection fraction ≤30%.

CONCLUSION

On-pump coronary artery bypass grafting can be performed in patients with ejection fraction ≤30%, with reasonable mortality and morbidity rates.

Predictors of intra-aortic balloon pump insertion in coronary surgery and mid-term results

Background

We aimed to investigate the preoperative, operative, and postoperative factors affecting intra-aortic balloon pump (IABP) insertion in patients undergoing isolated on-pump coronary artery bypass grafting (CABG). We also investigated factors affecting morbidity, mortality, and survival in patients with IABP support.

Methods

Between January 2002 and December 2009, 1,657 patients underwent isolated CABG in İzmir Katip Celebi University Atatürk Training and Research Hospital. The number of patients requiring support with IABP was 134 (8.1%).

Results

In a multivariate logistic regression analysis, prolonged cardiopulmonary bypass time and prolonged operation time were independent predictive factors of IABP insertion. The postoperative mortality rate was 35.8% and 1% in patients with and without IABP support, respectively (p=0.000). Postoperative renal insufficiency, prolonged ventilatory support, and postoperative atrial fibrillation were independent predictive factors of postoperative mortality in patients with IABP support. The mean follow-up time was 38.55±22.70 months and 48.78±25.20 months in patients with and without IABP support, respectively. The follow-up mortality rate was 3% (n=4) and 5.3% (n=78) in patients with and without IABP support, respectively.

Conclusion

The patients with IABP support had a higher postoperative mortality rate and a longer length of intensive care unit and hospital stay. The mid-term survival was good for patients surviving the early postoperative period.

Preoperative estimated glomerular filtration rate as a significant predictor of long-term outcomes after coronary artery bypass grafting in Japanese patients

PURPOSES

The aim of this retrospective study was to investigate the effect of chronic kidney disease (CKD) on outcomes after coronary artery bypass grafting (CABG), and to determine whether preoperative estimated glomerular filtration rate (eGFR) can be a predictor of long-term outcomes after CABG.

METHODS

486 Japanese patients who underwent isolated CABG between December 2000 and August 2010 were evaluated. Preoperative eGFR was estimated by the Japanese equation according to guidelines from the Japanese Society of Nephrology. We defined CKD as a preoperative eGFR of less than 60 ml/min/1.73 m(2). 203 patients had CKD (CK group) and 283 patients did not (N group).

RESULTS

During a mean observation time of 53 months, the overall survival rate was significantly lower in the CK group than in the N group (p = 0.0044). Similarly, the CK group had significantly more unfavorable results with regard to freedom from cardiac death, major adverse cardiovascular and cerebrovascular events (MACCE), and hemodialysis. Using multivariate analyses, preoperative eGFR was an independent predictor of all-cause mortality (HR 0.983; p = 0.026), cardiac mortality (HR 0.963; p = 0.006), and incidence of MACCE (HR 0.983; p = 0.002).

CONCLUSIONS

The CK group had significantly more unfavorable outcomes than the N group. Preoperative eGFR was an independent predictor of long-term outcomes after CABG in Japanese patients.

Decision making and results of coronary artery bypass grafting for patients with poor left ventricular function

BACKGROUND

The aim of this study is to determine the results of coronary artery bypass surgery in patients with a low ejection fraction. Between January 2007 and January 2011, 3556 consecutive patients who underwent coronary artery bypass grafting at the Cardiovascular Surgery Clinic at Sifa University Hospital, Izmir, Turkey, were analyzed retrospectively.

METHODS

The patients were divided into 2 groups. Patients undergoing isolated first-time elective coronary bypass surgery were classified according to their preoperative ejection fraction; Patients in Group I had an ejection fraction between 20% and 35% with poor left ventricular function (n = 1246; 695 men and 551 women; mean age, 62.25 ± 5.72 years, range, 47-78 years). Control patients in Group II underwent elective coronary artery bypass grafting at the same time and had left ventricular ejection fraction between 36% and 49% (n = 2310; 1211 men and 1099 women; mean age, 61.83 ± 8.12 years, range, 41-81 years). The mean follow-up time for all patients was 24 ± 9.4 months (range, 12-48 months). Patients were followed postoperatively at the end of the first month and every 6 months. The left ventricular ejection fraction was assessed by transthoracic echocardiography.

RESULTS

The mean number of distal anastomoses, myocardial infarction, and mean age was not significantly different between the 2 groups; however, cross-clamp time was longer in Group I. Patient recovery time was significantly longer in Group I. Morbidity (14.5% in Group I versus 7.4% in Group II, P < .005) and mortality (1.76% versus 0.30%, P < .005) were higher in Group I. During late follow-up, the 2-year survival rate (85.1% versus 94.5%) and 2-year event-free rate (77.6% versus 86.9%) were significantly lower in Group I when compared to Group II. Postoperative left ventricular ejection fraction values were significantly superior in Group I compared to Group II.

CONCLUSION

Coronary artery bypass grafting can be safely performed in patients with low ejection fraction with minimal postoperative morbidity and mortality. The viable myocardium could be reliably determined by positron emission tomography. Low ejection fraction patients could greatly benefit from coronary bypass surgery regarding postoperative ejection fraction, increased long-term survival, improvement in New York Heart Association classification, and higher quality of life.

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.

Recovery of left ventricular function after percutaneous revascularization of a left main chronic total occlusion

Surgical revascularization of left main and/or three-vessel coronary artery disease (CAD) is associated with improved survival in patients with left ventricular dysfunction when compared to medical therapy and can result in improved left ventricular ejection fraction (LVEF) [1]. Multivessel percutaneous coronary intervention (PCI) is equivalent to surgery regarding short and intermediate term mortality, and left main PCI has emerged as a safe and effective alternate to surgical revascularization [2]. However, outcomes of unprotected left main PCI in patients with severely depressed LVEF have not been examined. We report a patient with left main chronic total occlusion, multivessel CAD, and dilated cardiomyopathy, in whom complete revascularization via PCI resulted in decreased left ventricular size and improved LVEF.

Predictors of low cardiac output syndrome after isolated coronary artery bypass surgery: trends over 20 years

BACKGROUND

Postoperative low cardiac output syndrome (LCOS) is associated with high morbidity and mortality after coronary artery bypass grafting (CABG). We sought to examine trends in predictors of LCOS after isolated CABG.

METHODS

A total of 25,176 consecutive patients who underwent isolated CABG between 1990 and 2009 were included. To examine trends over time, we divided patients into four equivalent eras (1990 to -1994, n = 6,489; 1995 to 1999, n = 8,175; 2000 to 2004, n = 6,741; 2005 to 2009, n = 3,797). We used multivariable analysis to identify predictors of LCOS.

RESULTS

The prevalence of LCOS declined from 9.1% (1990 to 1994) to 2.4% (2005 to 2009, p < 0.001). The following were the major independent predictors of LCOS for the entire cohort (odds ratios in parentheses): reoperative CABG (4.1); earlier year of operation (4.1, 2.6, 1.7 for the first, second, and third eras, respectively); left ventricular ejection fraction (LVEF) less than 0.20 (3.5), emergency surgery (2.7), cardiogenic shock (2.3), female gender (2), and LVEF 0.20 to 0.39 (2). Unlike other risk factors, the impact of LVEF less than 0.20 on development of postoperative LCOS increased substantially in the latest era (odds ratio, 7.8) compared with (odds ratios, 3.1, 4.3, and 3.2) the first, second, and third eras, respectively.

CONCLUSIONS

The impact of LVEF less than 0.20 on development of postoperative LCOS has increased markedly in the latest era of our study. Prudent preoperative evaluation in patients with severe left ventricular dysfunction is critical. Further innovative research in myocardial protection and circulatory support is warranted in patients with severe left ventricular dysfunction.

Risk of adverse events after coronary artery bypass graft and subsequent noncardiac surgery

Aims: Coronary artery bypass grafts (CABGs) are increasingly performed in elderly patients. Risk factors and outcomes are poorly described for those undergoing noncardiac surgery within 1 year after CABG. Our objectives were to assess the risk and predictors of major adverse events associated with noncardiac surgery within 1 year after CABG. Methods: In a retrospective review of medical records at Mayo Clinic (Rochester, MN, USA), over a period of 5 years, we identified patients who underwent noncardiac procedures within 1 year post-CABG. All events that occurred within 30 days after noncardiac surgery and deaths within 1 year after noncardiac surgery were considered to be related to CABG. Results: We identified 211 patients; of these, 21 patients had 24 adverse events. Within 1 year, 11 died, and within the first 30 days, three myocardial infarctions, six acute congestive heart failure episodes, three cerebrovascular accidents and one deep vein thrombosis episode had occurred. Predictors of an adverse event included emergency operation (odds ratio: 6.8), ejection fraction less than 45% (p < 0.001) and elevated right ventricular systolic pressure by 40 mmHg or more (p = 0.03). After the noncardiac procedure, patients requiring dialysis (p = 0.02), ventilatory support (p = 0.03) and longer hospital stay (p = 0.03) had greater rates of adverse outcomes. Conclusion: Post-CABG, preoperative ejection fraction less than 45%, right ventricular systolic pressure of 40 mmHg or more, as well as emergent noncardiac surgery, were predictors of adverse outcomes after the noncardiac procedure. Longer postoperative hospital stay, dialysis, as well as ventilatory support, were predictors of adverse outcomes after CABG.

Preoperative ejection fraction as a predictor of survival after coronary artery bypass grafting: comparison with a matched general population

BACKGROUND

Preoperative left ventricular dysfunction is an established risk factor for early and late mortality after revascularization. This retrospective analysis demonstrates the effects of preoperative ejection fraction on the short-term and long-term survival of patients after coronary artery bypass grafting.

METHODS

Early and late mortality were determined retrospectively in 10 626 consecutive patients who underwent isolated coronary bypass between January 1998 and December 2007. The subjects were divided into 3 groups according to their preoperative ejection fraction. Expected survival was estimated by comparison with a general Dutch population group described in the database of the Dutch Central Bureau for Statistics. For each of our groups with a known preoperative ejection fraction, a general Dutch population group was matched for age, sex, and year of operation.

RESULTS AND DISCUSSION

One hundred twenty-two patients were lost to follow-up. In 219 patients, the preoperative ejection fraction could not be retrieved. In the remaining patients (n = 10 285), the results of multivariate logistic regression and Cox regression analysis identified the ejection fraction as a predictor of early and late mortality. When we compared long-term survival and expected survival, we found a relatively poorer outcome in all subjects with an ejection fraction of < 50%. In subjects with a preoperative ejection fraction of > 50%, long-term survival exceeded expected survival.

CONCLUSIONS

The severity of left ventricular dysfunction was associated with poor survival. Compared with the survival of the matched general population, our coronary bypass patients had a worse outcome only if their preoperative ejection fraction was < 50%.

New-onset atrial fibrillation predicts long-term mortality after coronary artery bypass graft

OBJECTIVES

We sought to investigate the association between new-onset atrial fibrillation after coronary artery bypass graft (CABG) (post-operative atrial fibrillation [POAF]) and long-term mortality in patients with no history of atrial fibrillation.

BACKGROUND

POAF predicts longer hospital stay and greater post-operative mortality.

METHODS

A total of 16,169 consecutive patients with no history of AF who underwent isolated CABG at our institution between January 1, 1996, and December 31, 2007, were included in the study. All-cause mortality data were obtained from Social Security Administration death records. A multivariable Cox proportional hazards regression model was constructed to determine the independent impact of new-onset POAF on long-term survival after adjusting for several covariates. The covariates included age, sex, race, pre-operative risk factors (ejection fraction, New York Heart Association functional class, history of myocardial infarction, index myocardial infarction, stroke, chronic obstructive pulmonary disease, peripheral arterial disease, smoking, diabetes, renal failure, hypertension, dyslipidemia, creatinine level, dialysis, redo surgery, elective versus emergent CABG, any valvular disorder) and post-operative adverse events (stroke, myocardial infarction, acute respiratory distress syndrome, and renal failure), and discharge cardiac medications known to affect survival in patients with coronary disease.

RESULTS

New-onset AF occurred in 2,985 (18.5%) patients undergoing CABG. POAF independently predicted long-term mortality (hazard ratio: 1.21; 95% confidence interval: 1.12 to 1.32) during a mean follow-up of 6 years (range 0 to 12.5 years). This association remained true after excluding from the analysis those patients who died in-hospital after surgery (hazard ratio: 1.21; 95% confidence interval: 1.11 to 1.32). Patients with POAF discharged on warfarin experienced reduced mortality during follow-up.

CONCLUSIONS

In this large cohort of patients, POAF predicted long-term mortality. Warfarin anticoagulation may improve survival in POAF.

Off-Pump Coronary Artery Bypass Surgery in Severe Left Ventricular Dysfunction

Our aim was to examine hospital outcomes of coronary artery bypass surgery in patients with and without left ventricular dysfunction, with regard to the surgical technique (off- or on-pump). Between March 2007 and March 2008, 689 consecutive patients underwent isolated first-time coronary artery bypass; 127 had ejection fractions ≤30% (group 1) and 562 had ejection fractions >30% (group 2). Data of preoperative risk profiles and hospital outcomes were collected prospectively. Off-pump operations were performed in 49 (38.6%) patients in group 1 and 196 (34.9%) in group 2. The incidences of infectious, neurologic, and cardiac complications postoperatively were significantly higher in group 1. In multivariate analysis, preoperative ejection fraction ≤30% was found to be an independent risk factor for postoperative complications and hospital mortality. The subgroup of patients undergoing off-pump surgery in both groups had a significantly lower rate of total complications than those undergoing conventional on-pump operations, but no significant difference in mortality was observed between those undergoing off-pump or conventional surgery in either group. Off-pump surgery helped to limit the increased morbidity rate after coronary bypass in patients with ventricular dysfunction.

Is severely left ventricular dysfunction a predictor of early outcomes in patients with coronary artery bypass graft?

BACKGROUND

Traditionally, the Coronary artery bypass grafting (CABG) surgery outcomes of patients with low ejection fraction (EF) have been worse compared to patients with moderate to good left ventricular function. During the past decade, despite improvements in surgical techniques, the trend in the outcomes of these patients remained unclear.

AIM

We sought to determine the effect of left ventricular dysfunction on early mortality and morbidity and to specify predictors of early mortality of isolated CABG in a large group of patients EF≤35%.

METHOD

We retrospectively analyzed data of 14 819 consecutive patients undergoing isolated CABG from February 2002 to March 2008 at Tehran Heart Center. Patients were divided into two groups based on their LVEF (EF≤35% and EF>35%). Differences in case-mix between patients with EF≤35% and those without were controlled by constructing a propensity score.

RESULTS

Mean age of our patients was 58.7±9.5 years. EF≤35% was present in 1342 (9.1%) of patients. In-hospital mortality was significantly increased univariate in EF≤35%, while this association diminished after confounders were adjusted for by using the propensity score (p=0.242). Following adjustment it was demonstrated that renal failure, cardiac arrest, heart block, infectious complication, total ventilation time, and total ICU hours were more frequent in patients with EF≤35%.

CONCLUSION

We demonstrated EF≤35% was not predictor of in-hospital mortality in patients underwent CABG. Careful preoperative patient selection remains essential in patients with EF≤35% undergoing CABG.

Preoperative evaluation and preparation of the patient for cardiac surgery

Cardiac surgery is associated with significant morbidity, mortality, and socioeconomic costs. Preoperative assessment assists the clinician in identifying potential complications and facilitates discussion of these risks with the patient. Careful patient selection and preparation during preoperative evaluation may minimize morbidity, mortality, and resource use. This article outlines a system-based approach to preoperative evaluation and preparation of the patient undergoing cardiac surgery.

Preoperative evaluation and preparation of the patient for cardiac surgery

Cardiac surgery is associated with significant morbidity, mortality, and socioeconomic costs. Preoperative assessment assists the clinician in identifying potential complications and facilitates discussion of these risks with the patient. Careful patient selection and preparation during preoperative evaluation may minimize morbidity, mortality, and resource use. This article outlines a system-based approach to preoperative evaluation and preparation of the patient undergoing cardiac surgery.

Four-chamber pacing in patients with poor ejection fraction but normal QRS durations undergoing open heart surgery

BACKGROUND

Poor ejection fraction (EF) comprises a critical risk factor in cardiac bypass surgery (CABG). It has been unclear, whether biventricular or four-chamber pacing confers benefit upon patients with intact atrioventricular and interventricular conduction especially following surgery.

METHODS

Twenty-one consecutive patients with an EF <or= 35% underwent hemodynamic evaluation (continuous pressures and thermodilution) 3, 6, and 18 hours post-CABG and biatrial (AA), biatrial-right ventricular (AAV), and biatrial-biventricular (AAVV) pacing were compared.

RESULTS

Patients (65 +/- 9 years) presented with an average EF of 29.5% (15-35%). 514 measurements of cardiac index (CI) were taken. Nineteen patients (91%) showed highly significant increases in CI with AAVV as compared to AA pacing (P < 0,001) at all times post surgery. The increase in CI with pacing mode varied from 6% to 25% and decreased with time following surgery. No consistent difference in CI was seen between four-chamber (AAVV) and biventricular pacing (AVV). The QRS-widths prior to surgery never exceeded 120 ms; postoperatively QRS-complexes widened in all patients on average by 15.9 ms +/-6 and returned to starting values by 48 hours.

CONCLUSIONS

Biventricular pacing improves CI in patients with poor EF following cardiac surgery in the absence of preoperative atrioventricular- or interventricular conduction block. This benefit decreases with time after surgery as the QRS width returns to preoperative values. Four-chamber pacing did not confer additional benefit as compared to biventricular pacing in this series. Biventricular pacing should be considered as an adjunct in patients with critically low EF undergoing cardiac surgery.

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.

The rationale and design of the Surgical Treatment for Ischemic Heart Failure (STICH) trial

OBJECTIVES

The rationale and design of the Surgical Treatment for Ischemic Heart Failure trial is described. Before the Surgical Treatment for Ischemic Heart Failure trial, less than 1000 patients with ischemic cardiomyopathy had been studied in randomized comparisons of medical therapy versus coronary artery bypass grafting. Trial data reflect how these therapies were delivered more than 20 years ago and do not indicate the relative benefits of medical therapy versus coronary artery bypass grafting in contemporary practice.

METHODS

Randomization of consenting patients with heart failure, left ventricular ejection fraction of 0.35 or less, and coronary artery disease is based on whether patients are judged by attending physicians to be candidates only for coronary artery bypass grafting or can be treated with medical therapy without coronary artery bypass grafting. Patients eligible for surgical ventricular reconstruction because of significant anterior wall akinesis or dyskinesis but ineligible for medical therapy are randomly assigned to coronary artery bypass grafting with or without surgical ventricular reconstruction. Patients eligible for medical therapy are randomly assigned between medical therapy only and medical therapy with coronary artery bypass grafting. Patients eligible for all 3 are randomly assigned evenly to medical therapy only, medical therapy and coronary artery bypass grafting, or medical therapy and coronary artery bypass grafting and surgical ventricular reconstruction. Major substudies will examine quality of life, cost-effectiveness, changes in left ventricular volumes, effect of myocardial viability, selected biomarkers, and selected polymorphisms on treatment differences.

RESULTS

Enrollment is now complete in both STICH hypotheses. Follow-up will continue until sufficient end points are available to address both hypotheses with at least 90% power. The primary outcome of hypothesis 2 is expected to be reported in 2009. The primary outcome of hypothesis 1 is expected to be reported in 2011.

CONCLUSIONS

The Surgical Treatment for Ischemic Heart Failure trial is a National Heart, Lung, and Blood Institute-funded multicenter international randomized trial addressing 2 specific primary hypotheses: (1) coronary artery bypass grafting with intensive medical therapy improves long-term survival compared with survival with medical therapy alone, and (2) in patients with anterior left ventricular dysfunction, surgical ventricular reconstruction to a more normal left ventricular size plus coronary artery bypass grafting improves survival free of subsequent hospitalization for cardiac cause when compared with that with coronary artery bypass grafting alone.

Excellent Results of Contemporary Coronary Artery Bypass Grafting with Systematic Application of Modern Perioperative Strategies

BACKGROUND

The patient population referred for coronary artery bypass grafting (CABG) has become more challenging. The surgical population is aging and patients present with significant preoperative comorbidities. This worsening risk profile has led to the development of operative techniques (off-pump CABG) and perioperative measures (epi-aortic scanning, intensive insulin therapy) to preserve the quality of care following CABG. The aim of this study was to determine the outcome of contemporary CABG following the implementation of the above measures in our practice.

METHODS

We retrospectively analyzed prospectively collected data of 2725 patients undergoing CABG between 01/1998 and 12/2005 (mean age, 65 +/- 11 years; 843 [31%] female; mean ejection fraction, 45% +/- 14%). Outcome measures included hospital mortality, postoperative complications, and long-term survival and independent predictors of outcome. Subgroup analyses were performed for 2 study periods (1998-2002 versus 2003-2005) where the above measures were implemented and for patients undergoing conventional versus off-pump CABG.

RESULTS

When comparing the 2 study periods, we observed a substantial worsening of the risk profile with an increased EuroSCORE predicted mortality from 6.4% +/- 6.8% to 7.0% +/- 7.8% (P = .028). During the same period, operative mortality decreased from 2.4% to 0.7% (P < .001). This reduction in mortality was also observed in diabetic patients (3.1% versus 1.0%, P = .021) and those with low ejection fraction (4% versus 2.6%, P = not significant). Off-pump procedures were performed with an increasing frequency in high-risk patients in whom we obtained excellent results. Finally, we observed a reduction of postoperative complications including respiratory failure (P = .013), gastrointestinal complications (P = .017), and stroke (P = .094). Independent predictors of mortality included renal failure (OR = 5.7), peripheral vascular disease (OR = 2.9), intra-aortic balloon pump (OR = 4.8), reoperation (OR = 3.3), and hypertension (OR = 2.3).

CONCLUSION

Despite a worsening case mix, contemporary CABG can be performed with excellent results (operative mortality < 1%). Off-pump CABG performed in very high-risk patients obtains results similar to those of the general CABG population. Diabetes and ejection fraction were not independent predictors of early outcome. In our experience, these excellent outcomes were achieved by adopting an operative approach using modern perioperative management (epi-aortic scanning, intensive insulin therapy) and surgical techniques (off-pump CABG) based on individual patients.

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

BACKGROUND

There are few data regarding medium-term outcome of coronary artery bypass grafting (CABG) in patients with severe left ventricular (LV) systolic dysfunction, particularly in the modern era, and even less assessing preoperative factors that might identify patients at highest risk.

METHODS AND RESULTS

Three hundred seventy-nine consecutive patients with LV ejection fraction < or = 35%, who underwent isolated first CABG between 1995 and 1999 were studied. Potential preoperative and perioperative predictors of outcome were recorded and patients followed-up for a median of 3.8 years. The primary study end-point was all-cause mortality. The 30-day, 1-year, and 3-year survival rates were 94.5%, 88%, and 81%, respectively. The independent predictors of mortality were preoperative estimated glomerular filtration rate (hazard ratio [HR], 0.98; 95% confidence interval [CI], 0.97 to 0.99 per mL/min/1.73 m2; P<0.001) and age (HR, 1.03; 95% CI, 1.01 to 1.06 per year; P=0.005).

CONCLUSIONS

Patients with significant LV systolic dysfunction undergoing isolated CABG using contemporary techniques have a good medium-term survival. Renal dysfunction is the strongest independent predictor of mortality.