Association of HbA1c and utilization of internal mammary arteries with wound infections in CABG

Background

Deep sternal wound infection (DSWI) remains a serious complication after coronary artery bypass grafting (CABG). We herein aimed to stratify diabetic patients who underwent CABG using bilateral internal mammary artery (BIMA) for levels of glycated hemoglobin A1C (HbA1c) and compare postoperative outcomes.

Methods

Between January 2010 and August 2020, 4,186 consecutive patients underwent isolated CABG at our center. In 3,229 patients, preoperative HbA1c levels were available. Primary endpoints were wound healing disorder (WHD), DSWI, and 30-day mortality. Patients were stratified according to preoperative HbA1c levels. Patients were further divided into subgroups according to utilization of BIMA.

Results

After adjustment, no differences in mortality and stroke rates were seen between group 1 (HbA1c < 6.5%) vs. group 2 (HbA1c ≥ 6.5%). WHD was more frequent in group 2 [2.8 vs. 5.6%; adjusted p = 0.002; adjusted odds ratio (OR), 1.853 (1.243-2.711)] but not DSWI [1.0 vs. 1.5%; adjusted p = 0.543; adjusted OR, 1.247 (0.612-2.5409)]. BIMA use showed a higher rate of WHD [no BIMA: 3.0%; BIMA: 7.7%; adjusted p = 0.002; adjusted OR, 4.766 (1.747-13.002)] but not DSWI [no BIMA: 1.1%; BIMA: 1.8%; adjusted p = 0.615; adjusted OR, 1.591 (0.260-9.749)] in patients with HbA1c ≥ 6.5%.

Conclusions

Intraoperative utilization of BIMA is not connected with an increase of DSWI but higher rates of WHD in patients with poor diabetic status and HbA1c ≥ 6.5%. Therefore, application of BIMA should be taken into consideration even in patients with poor diabetic status, while identification of special subsets of patients who are at particular high risk for DSWI is of paramount importance to prevent this serious complication.

On- versus off-pump CABG in octogenarians: A propensity-matched analysis from the UK National Database

INTRODUCTION

Coronary artery bypass grafting (CABG) remains a good revascularization strategy in octogenarians with excellent clinical outcomes and quality of life postoperatively. However, the benefits of off-pump over on-pump CABG in the elderly population are still controversial. We investigated this issue in the UK National Audit database.

METHOD

We retrospectively analyzed all octogenarians undergoing nonemergency, isolated CABG from 1996 to 2019. Propensity score matching (PSM) was conducted to adjust for imbalance in the baseline characteristics between the off-pump and on-pump groups. Primary outcome was in-hospital mortality and postoperative cerebrovascular accidents. Secondary outcomes were bleeding requiring reoperation, deep sternal wound infection, and postoperative dialysis.

RESULT

A total of 6436 patients were included for analysis. No differences were observed between off- and on-pump group in-hospital mortality (4% vs. 3.8%, p = .89), return to theater rate (5.4% vs. 6.2%, p = .16) and incidence of deep sternal wound infection (1.1% vs. 1.6%, p = .34). However, octogenarian undergoing off-pump CABG were less likely to experience postoperative transient ischemic attack (TIA)/stroke (1.4% vs. 2.3%, p = .004) but more likely to require renal dialysis (4.8% vs. 3.5%, p = .03).

CONCLUSION

The data show similar in-hospital mortality in octogenarians regardless of the revascularization technique used. Off-pump when compared with on-pump CABG is associated with a lower incidence in postoperative neurological events but a higher need for renal dialysis.

Off-Pump Coronary Artery Bypass Grafting; is it Still Relevant?

Off-pump Coronary Artery Bypass Grafting (OPCAB) experienced a resurgence in the 1980s -2000s and developed steadily with improvement of the instrumentation and techniques. However questions about graft patency and long-term survival of OPCAB patients still exist. This review attempts to explore the current relevance of OPCAB.

Intimal aortic atherosclerosis in cardiac surgery: surgical strategies to prevent embolic stroke

 

OBJECTIVES

Although the incidence of perioperative stroke after cardiac surgery gradually decreased over the last decades, there is much variation between centres. This review aimed to create a concise overview of the evidence on possible surgical strategies to prevent embolic stroke in patients with intimal aortic atherosclerosis.

METHODS

The PubMed and EMBASE databases were searched for studies on surgical management of aortic atherosclerosis and the association with perioperative stroke in cardiac surgery, including specific searches on the most common types of surgery. Articles were screened with emphasis on studies comparing multiple strategies and studies reporting on the patients’ severity of aortic atherosclerosis. The main findings were summarized in a figure, with a grade of the corresponding level of evidence.

RESULTS

Regarding embolic stroke risk, aortic atherosclerosis of the tunica intima is most relevant. Although several strategies in general cardiac surgery seem to be beneficial in severe disease, none have conclusively been proven most effective. Off-pump surgery in coronary artery bypass grafting should be preferred with severe atherosclerosis, if the required expertise is present. Although transcatheter aortic valve replacement is used as an alternative to surgery in patients with a porcelain aorta, the risk profile concerning intimal atherosclerosis remains poorly defined.

CONCLUSIONS

A tailored approach that uses the discussed alternative strategies in carefully selected patients is best suited to reduce the risk of perioperative stroke without compromising other outcomes. More research is needed, especially on the perioperative stroke risk in patients with moderate aortic atherosclerosis.

Effects of Volatile Anesthetics on Postoperative Ischemic Stroke Incidence

Background

Preclinical studies suggest that volatile anesthetics decrease infarct volume and improve the outcome of ischemic stroke. This study aims to determine their effect during noncardiac surgery on postoperative ischemic stroke incidence.

Methods and Results

This was a retrospective cohort study of surgical patients undergoing general anesthesia at 2 tertiary care centers in Boston, MA, between October 2005 and September 2017. Exclusion criteria comprised brain death, age <18 years, cardiac surgery, and missing covariate data. The exposure was defined as median age‐adjusted minimum alveolar concentration of all intraoperative measurements of desflurane, sevoflurane, and isoflurane. The primary outcome was postoperative ischemic stroke within 30 days. Among 314 932 patients, 1957 (0.6%) experienced the primary outcome. Higher doses of volatile anesthetics had a protective effect on postoperative ischemic stroke incidence (adjusted odds ratio per 1 minimum alveolar concentration increase 0.49, 95% CI, 0.40–0.59, P<0.001). In Cox proportional hazards regression, the effect was observed for 17 postoperative days (postoperative day 1: hazard ratio (HR), 0.56; 95% CI, 0.48–0.65; versus day 17: HR, 0.85; 95% CI, 0.74–0.99). Volatile anesthetics were also associated with lower stroke severity: Every 1‐unit increase in minimum alveolar concentration was associated with a 0.006‐unit decrease in the National Institutes of Health Stroke Scale (95% CI, −0.01 to −0.002, P=0.002). The effects were robust throughout various sensitivity analyses including adjustment for anesthesia providers as random effect.

Conclusions

Among patients undergoing noncardiac surgery, volatile anesthetics showed a dose‐dependent protective effect on the incidence and severity of early postoperative ischemic stroke.

Off-pump versus on-pump coronary artery surgery in octogenarians (from the KROK Registry)

Background

According to the medical literature, both on-pump and off-pump coronary artery surgery is safe and effective in octogenarians.

Objectives

The aim of our study was to examine the epidemiology, in-hospital outcomes and long-term follow-up results in octogenarians undergoing off-pump and on-pump coronary artery surgery utilizing nationwide registry data.

Methods

All octogenarians (≥ 80 years) enrolled in the Polish National Registry of Cardiac Surgical Procedures (KROK Registry), who underwent isolated coronary surgery between January 2006 and September 2017 were identified. Preoperative data, perioperative complications, hospital mortality and long-term mortality were analyzed. Unadjusted and propensity-matched comparisons were performed between octogenarians undergoing off-pump and on-pump coronary artery bypass surgery.

Results

Octogenarians accounted for 4.1% of the total population undergoing coronary artery surgery in Poland during the analyzed period (n = 152,631) and this percentage is increasing. Among 6,006 analyzed patients, 2,744 (45.7%) were operated on-pump and 3,262 (54.3%) were operated off-pump. Propensity-matched analysis revealed that patients operated on-pump were more often reoperated due to postoperative bleeding and their in-hospital mortality was higher (6.6% vs 4.5%, p = 0.006 and 8.7% vs 5.8%, p = 0.001, respectively). Long-term all-cause mortality was lower among patients operated off-pump (p = 0.013).

Conclusion

On the basis of our findings we suggest that off pump technique should be considered as perfectly acceptable in octogenarians.

Current Status of Off-Pump Coronary Artery Bypass

PURPOSE

Off-pump coronary arterial bypass grafting (OPCAB) has become a common practice for coronary artery bypass grafting (CABG) in Japan, with approximately 65% CABG procedures currently being performed using OPCAB. However, it is unclear whether OPCAB is superior in terms of associated mortality, incidence of complications, graft patency rate, and long-term outcomes compared with conventional CABG (CCABG).

METHODS

Literature consideration was performed, mainly based on observational studies involving large samples and randomized controlled trials (RCTs).

RESULTS

Many RCTs indicated that the acute-phase and long-term mortality rates were comparable between CCABG and OPCAB or that OPCAB was inferior to CCABG. In contrast, many observational studies indicated that OPCAB was superior to CCABG.

CONCLUSION

CABG is a delicate procedure, the outcomes of which vary in accordance with the patient's condition as well as the level of expertise of the associated institution and surgeon. In the future, we hope that reports will emerge with excellent results, including long-term results, from Japanese institutions experienced in performing OPCAB.

Off-pump Techniques of Surgical Myocardial Revascularization

BACKGROUND

Before the advent of CABG, standardized in the late '60s by Favaloro and Effler, patients with myocardial ischemia underwent indirect and heterogeneous off-pump methods of myocardial revascularization.

METHODS & RESULTS

Indirect revascularization, such as periaortic nerve plexus interruption, Vineberg operation, Sen procedure and, less remotely, TMR Laser and stem cell transplantation, represented some of the ways to achieve myocardial revascularization. Nowadays, direct coronary revascularization is the only established technique and may be performed either on-pump or off-pump.

CONCLUSION

The comparison of off-pump and on-pump myocardial revascularization paved the way to an endless debate between the advantages and disadvantages of each technique. In this article, we review the old and current off-pump approaches of surgical myocardial revascularization.

Use of cardiopulmonary pump support during coronary artery bypass grafting in the high-risk: a meta-analysis

BACKGROUND

Data from randomized trials evaluating the efficacy of on- versus off-pump coronary artery bypass grafting remain inconclusive, particularly in high-risk populations.

AIMS

The aim of this study is to compare the outcomes associated with on- versus off-pump coronary artery bypass grafting among high-risk patients.

METHODS

We performed a meta-analysis of randomized control trials comparing on- versus off-pump coronary artery bypass grafting, focusing on high-risk populations. Studies focusing on "high-risk" features: European System of Cardiac Operative Risk Evaluation (EuroSCORE) ≥ 5, age > 70 years, preexisting renal insufficiency, history of stroke(s), and the presence of left ventricular dysfunction were included. MEDLINE, Scopus, and Embase were searched for all publications between January 1, 2000 and August 1, 2016, using the following terms: on-pump, off-pump, coronary artery bypass, high-risk, left ventricular dysfunction, elderly, aged, and renal insufficiency. Endpoints included cardiovascular and all-cause mortality, non-fatal myocardial infarction, stroke, need for revascularization, renal failure, and length of hospital stay.

RESULTS

Nine studies incorporating 11,374 patients with a mean age of 70 years were selected. There was no statistical difference in cardiovascular mortality, all-cause mortality, non-fatal myocardial infarction, and renal failure between the two groups. There was a decrease in further revascularization at 1 year with on-pump (OR 0.67 (0.50-0.89)). However, there was an increase in length of hospital stay by 2.24 days (p = 0.03) among the on-pump group with no difference in stroke (OR 1.34 (1.00-1.80)).

CONCLUSIONS

On-pump is associated with a decreased risk of additional revascularization by 1 year. However, this appears to be a cost of longer hospitalization.

On- or off-pump coronary artery bypass grafting for octogenarians: A meta-analysis of comparative studies involving 27,623 patients

OBJECTIVE

Coronary artery bypass grafting (CABG) is being increasingly offered to octogenarians. Both on- and off-pump CABG are reported as effective surgical revascularization strategies for octogenarians by single institution studies. However, the issue of superiority of one strategy over the other for octogenarians remains unresolved due to limited sample size of these studies. A meta-analysis of studies comparing outcomes of on- and off-pump CABG in octogenarians was undertaken to address the issue.

METHODS

A literature search was conducted from 1966 through September 2016 using MEDLINE, EMBASE, Scopus and Web of Science to identify relevant articles. Primary outcomes of interest included in-hospital mortality and stroke. Secondary outcomes of interest were atrial fibrillation, acute renal failure, reoperation for bleeding, deep sternal wound infection, myocardial infarction, intensive therapy unit (ITU) stay and hospital stay. The random effects model was used to calculate the outcomes of both binary and continuous data to control any heterogeneity between the studies. Heterogeneity amongst the trials was determined by means of the Cochran Q value and quantified using the I² inconsistency test. All p-values were 2-sided and a 5% level was considered significant.

RESULTS

Sixteen retrospective studies (18,685 on-pump patients and 8938 off-pump patients) were included in the systematic review. In-hospital mortality (pooled OR = 0.64, 95% CI = 0.44 to 0.93; p = 0.02), stroke rate (pooled OR = 0.61, 95% CI = 0.48 to 0.76; p < 0.001) and length of hospital stay (pooled WMD = +0.29, 95% CI = +0.02 to +0.56; p = 0.04) were significantly lower in the off-pump patients. Atrial fibrillation (p = 0.36), acute renal failure (p = 0.47), reoperation for bleeding (p = 0.99), deep sternal wound infection (p = 0.59), myocardial infarction (p = 0.93), and length of ITU stay (p = 0.27) were comparable.

CONCLUSION

Off-pump compared to on-pump CABG offers surgical myocardial revascularization to octogenarians with lower in-hospital mortality, stroke rate and length of hospital stay with similar incidence of other adverse outcomes. Preferentially offering off-pump CABG to octogenarians could translate into reduced economic burden on the healthcare providers.

Clampless versus clamped coronary bypass grafting: does it make a difference?

PURPOSE OF REVIEW

The techniques of coronary artery bypass grafting (CABG) have evolved remarkably over the last two decades since the introduction of off-pump coronary artery bypass (OPCAB). This article focuses on the clinical outcomes of 'clampless' CABG strategies, that include OPCAB with a partial clamp, OPCAB with a proximal suture device, and aorta no-touch OPCAB.

RECENT FINDINGS

Observational studies have shown the superiority of OPCAB for preventing strokes and pulmonary complications. Conversely, recent large-scale randomized controlled trials (RCTs) have been unable to demonstrate the benefits of OPCAB. Because of these differing results across numerous studies, the debate about the overall superiority of OPCAB versus on-pump CABG remains controversial. However, the literature regarding the OPCAB technique with minimized manipulation of the aorta suggests this has likely benefits, especially for high-risk patients.

SUMMARY

Previous large RCTs did not focus on specific approaches of OPCAB or the importance of the experience of surgeons and institutions, and so further studies are needed. Observational studies and meta-analyses have indicated that improved outcomes can be achieved by applying specific OPCAB approaches according to each patient's characteristics.

Comparison of outcomes between off-pump versus on-pump coronary artery bypass surgery in elderly patients: a meta-analysis

The aim of this study was to analyze if off-pump coronary artery bypass surgery (CABG) is associated with better treatment outcomes in elderly patients (>70 years of age) than on-pump CABG, using meta-analysis. Medline, PubMed, Cochrane and Google Scholar databases were searched until September 13, 2016. Sensitivity and quality assessment were performed. Twenty-two studies, three randomized control trials (RCTs) and 20 non-RCTs were included with 24,127 patients. The risk of death associated with on-pump or off-pump CABG in the RCTs were similar (pooled OR=0.945, 95%CI=0.652 to 1.371, P=0.766). However, in the non-RCTs, mortality risk was lower in patients treated with off-pump CABG than on-pump CABG (pooled OR=0.631, 95%CI=0.587 to 0.944, P=0.003). No differences were observed between the two treatment groups in terms of the occurrence of 30-day post-operative stroke or myocardial infarction (P≥0.147). In the non-RCTs, off-pump CABG treatment was associated with a shorter length of hospital stay (pooled standardized difference in means=-0.401, 95%CI=-0.621 to -0.181, P≤0.001). The meta-analysis with pooled data from non-RCTs, but not RCTs, found that mortality was lower with off-pump compared with on-pump CABG, and suggested that there may be some benefit of off-pump CABG compared with on-pump CABG in the risk of mortality and length of hospital stay.

The future of off-pump coronary artery bypass grafting: a North American perspective

Off-pump coronary artery bypass graft (OPCAB) is currently performed routinely in a minority of specialized centers and in many more centers, utilized only when a porcelain aorta mandates a no-touch aortic technique. The OPCAB literature can be summarized as follows: (I) large-scale randomized trials in relatively low risk patients that include surgeons with a range of experience demonstrating no consistent beneficial differences in major cardiovascular and cerebrovascular outcomes but lower transfusion rates and shorter length of stay, tempered by some reports of higher rates of incomplete revascularization and lower rates of long term graft patency; (II) smaller randomized controlled trials (RCTs) from highly specialized programs demonstrating equivalent or superior outcomes with OPCAB and similar completeness of revascularization and graft patency; and (III) observational data from large databases demonstrating a consistent benefit of OPCAB, especially in higher-risk patient subsets. Our rationale for OPCAB remains that if complete and precise revascularization can be safely and routinely accomplished, then the patient should benefit by avoiding the morbidities that can be attributed to aortic cannulation/clamping, cardiopulmonary bypass (CPB), hemodilution, hypothermia and global myocardial ischemia/cardioplegia. We further believe that OPCAB procedures should emphasize the use of arterial grafts to optimize long term patency and minimize aortic manipulation to limit the risk of stroke. Moving forward, the off-pump surgical community and specialty societies must address the challenge of training surgeons and their teams to master this technically demanding procedure. Furthermore, OPCAB opens the door to minimally-invasive surgical revascularization via hybrid coronary revascularization (HCR). A large NIH-funded RCT is currently underway to determine whether hybrid revascularization can offer a superior alternative to multi-vessel percutaneous coronary intervention for patients with low SYNTAX score and proximal LAD disease.

Off-pump coronary artery bypass grafting in octogenarians

Enhanced life expectancy has confronted cardiac surgery with a rapidly growing population of octogenarians needing coronary artery bypass grafting (CABG). Octogenarians are deemed a high-risk patient population with increased postoperative morbidity and mortality following conventional CABG using cardiopulmonary bypass (CPB). In such patients reducing the invasiveness of the surgical procedure by avoiding CPB may be tried in an attempt to improve outcomes. The increasing performance of off-pump coronary artery bypass (OPCAB) grafting within certain centers reflects surgeon preference to avoid the inherent risks of CPB and cardioplegic arrest including hemodilution, nonpulsatile arterial flow, global myocardial ischemia, atherosclerotic embolization from aortic manipulation, and systemic inflammatory response. Although OPCAB grafting is a well-established surgical myocardial revascularization strategy, its actual benefits in terms of morbidity and mortality remain questionable in the general population. In the higher risk octogenarian patients, however, there is a potential for more tangible clinical benefits when CPB is avoided. This review article provides an overview of the impact of OPCAB grafting on postoperative mortality and morbidity in octogenarians.

Cardiac surgery 2014 reviewed

For the year 2014, more than 17,000 published references can be found in Pubmed when entering the search term "cardiac surgery". The last year has been characterized by a vivid discussion in the fields where classic cardiac surgery and modern interventional techniques overlap. Specifically, there have been important contributions in the field of coronary revascularization with either percutaneous coronary intervention or bypass surgery as well as in the fields of interventional valve therapy. Here, the US core valve trial with the first demonstration of a survival advantage at 1 year with transcatheter valves compared to surgical aortic valve replacement or the 5-year outcome of the SYNTAX trial with significant advantages for bypass surgery has been the landmark. However, in addition to these most visible publications, there have been several highly relevant and interesting contributions. This review article will summarize the most pertinent publications in the fields of coronary revascularization, surgical treatment of valve disease, heart failure (i.e., transplantation and ventricular assist devices) and aortic surgery. This condensed summary will provide the reader with "solid ground" for up-to-date decision-making in cardiac surgery.

Off-pump coronary artery bypass reduces early stroke in octogenarians: a meta-analysis of 18,000 patients

BACKGROUND

Data comparing results of off-pump and conventional operations in octogenarians is very limited. Thus we chose to compare early adverse events between off-pump coronary artery bypass grafting (OPCABG) and on-pump CABG (ONCABG) in patients older than 80 years.

METHODS

Systematic review of multiple databases was performed to obtain original studies fulfilling search criteria. End points--early mortality, stroke, respiratory failure, atrial fibrillation, and myocardial infarction--were compared between these cohorts. A random-effects weighted analysis was performed using the trim-fill adjustment when necessary. Results are presented as risk ratios (RRs) with 95% confidence intervals (CIs); p < 0.05 is considered statistically significant.

RESULTS

Sixteen retrospective studies (9,744 ONCABG and 8,566 OPCABG patients) were included in the systematic review. OPCAGB patients received significantly fewer grafts (2.54 ± 0.16) compared with ONCABG patients (3.22 ± 0.41). Early mortality was comparable at 4.6% and 5.2% in the OPCABG and ONCABG cohorts, respectively (risk ratio [RR], 0.91; 95% CI, 0.64-1.28; p = 0.598). Stroke rates were higher in the ONCABG cohort (RR, 0.65; 95% CI, 0.49- 0.87; p < 0.01). Respiratory failure was higher with ONCABG (RR, 0.74; 95% CI, 0.57-0.97; p = 0.03). New-onset renal failure (p = 0.99), atrial fibrillation (p = 0.27), and myocardial infarction (p = 0.99) were comparable.

CONCLUSIONS

Coronary artery bypass in octogenarians can be performed safely with low early mortality. Although off-pump operations reduce the risk of early stroke, all other adverse events are comparable in on- and off-pump coronary artery bypass operations. Data regarding late mortality is at present limited; however, both on- and off-pump procedures appear to produce comparable survival.

On-pump versus off-pump coronary artery bypass graft surgery: what do the evidence show?

The main purpose of the off-pump coronary artery bypass surgery is to reduce morbidity and mortality due cardiopulmonary bypass. However, even though many studies have shown that off-pump coronary artery bypass is feasible and provides hospital morbidity and mortality similar to the on-pump coronary artery bypass graft surgery, probably better in some aspects, its long-term results have been questioned, since some trials have shown reduced survival with off-pump coronary artery bypass. It is likely that incomplete revascularization and/or poor graft patency with off-pump coronary artery bypass probably are responsible for such unfavorable outcome.