2011 ACCF/AHA Guideline for Coronary Artery Bypass Graft Surgery

Comparative Effectiveness of Coronary Artery Bypass Graft Surgery and Percutaneous Coronary Intervention for Patients With Coronary Artery Disease: A Meta-Analysis of Randomized Clinical Trials

Percutaneous coronary intervention (PCI) and coronary artery bypass graft (CABG) surgery are the options for revascularization in coronary artery disease (CAD). This meta-analysis aims to compare the efficacy of CABG and PCI for the management of patients with CAD. The meta-analysis was conducted as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, Cochrane Library, and EMBASE were searched for relevant articles. The reference list of included articles was also searched manually for additional publications. Primary endpoints were cardiovascular mortality and all-cause mortality. Secondary endpoints included myocardial infarction, stroke, and revascularization. In total, 12 randomized control trials (RCTs) were included in this meta-analysis encompassing 9,941 patients (4,954 treated with CABG and 4,987 with PCI). The analysis showed that PCI was associated with a higher risk of all-cause mortality (risk ratio (RR) = 1.26, 95% confidence interval (CI) = 1.10-1.45) and revascularization (RR = 2.42, 95% CI = 1.82-3.21). However, no significant differences were reported between two arms regarding cardiovascular mortality (RR = 1.15, 95% CI = 0.96-1.39), myocardial infarction (RR = 1.17, 95% CI = 0.82-1.67), and stroke (RR = 0.64, 95% CI = 0.35-1.16). CABG was associated with a significant reduction in all-cause mortality and revascularization compared to PCI. However, no significant difference was reported in the risk of cardiovascular mortality, myocardial infarction, and stroke between the two groups.

Early cardiac contractility outcome of reoperative coronary artery bypass grafting using right gastroepiploic artery

BACKGROUND AND AIM OF THE STUDY

Reoperative coronary artery bypass grafting (redo CABG) still carries higher mortality and increased morbidity compared with primary CABG. In this study, we retrospectively reviewed our operative outcome of redo CABG to evaluate the impact of the left anterolateral thoracotomy approach using the right gastroepiploic artery (RGEA).

METHODS

Between 1994 and 2020, 11 patients (mean age 60.3 ± 13.1 years; nine men, two women) underwent isolated redo CABG using the RGEA via the left anterolateral thoracotomy.

RESULTS

The mean duration from the initial CABG was 128.3 ± 88.4 months. Redo CABG was performed because of graft occlusion in six patients (54.5%), graft stenosis in one patient (9.1%), and progressive disease of previously ungrafted vessels in four patients (36.4%). The total number of bypasses using RGEA (including Y-composite vein grafts) was 16 (four left anterior descending branches, two diagonal branches, five circumflex branches, five right coronary arteries). No residual graft injury, major comorbidity, or in-hospital death was observed. Changes in echocardiographic values before and after redo CABG were 210.9 ± 48.2 ml and 175.0 ± 41.4 ml in left ventricular end-diastolic volume, 130.2 ± 49.2 ml and 94.4 ± 33.0 ml in left ventricular end-systolic volume, and 45.6 ± 11.0% and 52.2 ± 10.7% in left ventricular ejection fraction, respectively. These parameters significantly improved after redo CABG.

CONCLUSIONS

Redo CABG with RGEA grafting via the left anterolateral thoracotomy approach is a safe and effective surgical procedure especially in improving cardiac contractility in patients who required revascularization.

Levels of Evidence Supporting the North American and European Perioperative Care Guidelines for Anesthesiologists between 2010 and 2020: A Systematic Review

BACKGROUND

Although there are thousands of published recommendations in anesthesiology clinical practice guidelines, the extent to which these are supported by high levels of evidence is not known. This study hypothesized that most recommendations in clinical practice guidelines are supported by a low level of evidence.

METHODS

A registered (Prospero CRD42020202932) systematic review was conducted of anesthesia evidence-based recommendations from the major North American and European anesthesiology societies between January 2010 and September 2020 in PubMed and EMBASE. The level of evidence A, B, or C and the strength of recommendation (strong or weak) for each recommendation was mapped using the American College of Cardiology/American Heart Association classification system or the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. The outcome of interest was the proportion of recommendations supported by levels of evidence A, B, and C. Changes in the level of evidence over time were examined. Risk of bias was assessed using Appraisal of Guidelines for Research and Evaluation (AGREE) II.

RESULTS

In total, 60 guidelines comprising 2,280 recommendations were reviewed. Level of evidence A supported 16% (363 of 2,280) of total recommendations and 19% (288 of 1,506) of strong recommendations. Level of evidence C supported 51% (1,160 of 2,280) of all recommendations and 50% (756 of 1,506) of strong recommendations. Of all the guidelines, 73% (44 of 60) had a low risk of bias. The proportion of recommendations supported by level of evidence A versus level of evidence C (relative risk ratio, 0.93; 95% CI, 0.18 to 4.74; P = 0.933) or level of evidence B versus level of evidence C (relative risk ratio, 1.63; 95% CI, 0.72 to 3.72; P = 0.243) did not increase in guidelines that were revised. Year of publication was also not associated with increases in the proportion of recommendations supported by level of evidence A (relative risk ratio, 1.07; 95% CI, 0.93 to 1.23; P = 0.340) or level of evidence B (relative risk ratio, 1.05; 95% CI, 0.96 to 1.15; P = 0.283) compared to level of evidence C.

CONCLUSIONS

Half of the recommendations in anesthesiology clinical practice guidelines are based on a low level of evidence, and this did not change over time. These findings highlight the need for additional efforts to increase the quality of evidence used to guide decision-making in anesthesiology.

EDITOR’S PERSPECTIVE

Outcomes of Reoperative Coronary Artery Bypass Graft Surgery in the United States

Background

There is a paucity of data on the trends and outcomes of reoperative coronary artery bypass graft (CABG) surgery during the current decade in the United States.

Methods and Results

We queried the National Inpatient Sample database (2002–2016) for all hospitalizations with isolated CABG procedure. We reported the temporal trends and outcomes of reoperative CABG versus primary CABG procedures. The main outcome was in‐hospital mortality. Among 3 212 768 hospitalizations with CABG, 46 820 (1.5%) had reoperative CABG. Over the 15‐year study period, there were no changes in the proportion of reoperative CABG (1.8% in 2002 versus 2.2% in 2016, P_tren=0.08), and the related in‐hospital mortality (3.7% in 2002 versus 2.7% in 2016, P_trend=0.97). Reoperative CABG was performed in patients with increasingly higher risk profile. Compared with primary CABG, hospitalizations for reoperative CABG were associated with higher in‐hospital mortality (3.2% versus 1.9%, P<0.001), cardiac arrest, cardiogenic shock, vascular complications, and respiratory complications. Among hospitalizations for reoperative CABG, the predictors of higher mortality included history of heart failure and chronic kidney disease.

Conclusions

In this 15‐year nationwide analysis, reoperative CABG procedures were increasingly performed in patients with higher risk profile. In‐hospital mortality rates were relatively low and did not change during the examined period. Compared with primary CABG, reoperative CABG is associated with higher in‐hospital mortality.

The Impact of Anesthetic Regimen on Outcomes in Adult Cardiac Surgery: A Narrative Review

Despite improvements in surgical techniques and perioperative care, cardiac surgery still is burdened by relatively high mortality and frequent major postoperative complications, including myocardial dysfunction, pulmonary complications, neurologic injury, and acute kidney injury. Although the surgeon's skills and volume and patient- and procedure-related risk factors play a major role in the success of cardiac surgery, there is growing evidence that also optimizing perioperative care may improve outcomes significantly. The present review focuses on the aspects of perioperative care that are strictly related to the anesthesia regimen, with special reference to volatile anesthetics and neuraxial anesthesia, whose effect on outcome in adult cardiac surgery has been investigated extensively.

Coronary artery bypass surgery plus medical therapy versus medical therapy alone for ischaemic heart disease: a protocol for a systematic review with meta-analysis and trial sequential analysis

BACKGROUND

Despite increasing survival, cardiovascular disease remains the primary cause of death worldwide with an estimated 7.4 million annual deaths. The main symptom of ischaemic heart disease is chest pain (angina pectoris) most often caused by blockage of a coronary artery. The aim of coronary artery bypass surgery is revascularisation achieved by surgically grafting harvested arteries or veins distal to the coronary lesion restoring blood flow to the heart muscle. Older evidence suggested a clear survival benefit of coronary artery bypass graft surgery, but more recent trials yield less clear evidence. We want to assess the benefits and harms of coronary artery bypass surgery combined with different medical therapies versus medical therapy alone in patients with ischaemic heart disease.

METHODS

This protocol for a systematic review follows the recommendations of Cochrane and the eight-step assessment procedure suggested by Jakobsen and colleagues. We plan to include all randomised clinical trials assessing coronary artery bypass surgery combined with different medical therapies versus medical therapy alone in patients with ischaemic heart disease. We plan to search the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, LILACS, Science Citation Index Expanded on Web of Science, and BIOSIS to identify relevant trials. Any eligible trial will be assessed as high risk or low risk of bias, and our conclusions will primarily be based on trials at low risk of bias. The analyses of the extracted data will be performed using Review Manager 5, STATA 16 and trial sequential analysis. For both our primary and secondary outcomes, we will create a 'Summary of Findings' table and use GRADE to assess the certainty of the evidence.

DISCUSSION

Coronary artery bypass surgery is invasive and can cause death, which is why its use must be thoroughly studied to determine if it yields a large enough long-term benefit for the thousands of patients receiving it every year.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO ID 131924.

Vasoplegic syndrome in cardiac surgery: Definitions, pathophysiology, diagnostic approach and management

Vasoplegic syndrome is a state of vasopressor resistant systemic vasodilation in the presence of a normal cardiac output. Its definition, pathophysiology, risk factors, diagnosis and therapeutic approach will be reviewed in this paper. It occurs frequently during cardiac surgery and is associated with high morbidity and mortality. A search in the LILACS, MEDLINE, and GOOGLE SCHOLAR databases was conducted to find the most relevant papers during the last 18 years. Prompt identification and diagnosis of patients at risk must be undertaken in order to implement an optimal therapeutic approach. This latter includes early treatment with vasopressors with different mechanisms of action.

New-Onset Atrial Fibrillation in Adult Patients After Cardiac Surgery

Purpose of Review

An overview of recent literature regarding pathophysiology, risk factors, prophylaxis, and treatment of new-onset atrial fibrillation (AF) in post-cardiac surgical patients.

Recent Findings

AF is the most frequent adverse event after cardiac surgery with significant associated morbidity, mortality, and financial cost. Its causes are multifactorial, and models to stratify patients into risk categories are progressing but a consistent, evidence-based system has not yet been developed. Pharmacologic and surgical interventions to prevent and treat this complication have been an area of ongoing research and recent societal guidelines reflect this.

Summary

Inconsistencies remain surrounding how to best identify higher-risk AF patients, which interventions should be used to prevent and treat AF, and which patient groups should receive these interventions. The evidence for these available strategies and their place in contemporary guidelines are summarized.

Impact of Discontinuation of Antiplatelet Therapy Prior to Isolated Valve and Combined Coronary Artery Bypass Graft and Valve Procedures on Short and Intermediate Term Outcomes

BACKGROUND

A change in cardiac surgery practice over the past decade has seen an increase in urgent or inpatient referrals for surgery, with antiplatelet therapy often continued up until surgery. This study aims to identify the optimal timing for administration of aspirin to minimise risk of perioperative morbidity and mortality.

METHODS

From a prospectively compiled database collected by the Australian and New Zealand Society of Cardiac and Thoracic Surgeons, we identified 8294 patients undertaking combined CABG and valve or isolated valve procedures while discontinuing aspirin. Time points for cessation of antiplatelet therapy were categorised as follows: <2 days, 3-7 days or >7 days preoperatively. We evaluated the association of adverse in-hospital events and intermediate term survival in each time category.

RESULTS

Discontinuing aspirin 3 to 7 days from surgery decreased rates of perioperative MI (HR=0.300, p=0.027), return to theatre (HR=0.560, p=0.002) reduced drain output (HR=0.757, p=0.000) and red blood cell and platelet transfusions (HR=0.719, p=0.000 and HR=0.604, p=0.000 respectively) compared to patients continuing aspirin until <2 days from the procedure. Stopping aspirin <2 days from the date of surgery increased risk of perioperative MI (HR=5.919, p=0.000), reoperation for bleeding (HR=2.076, p=0.001), returning to theatre (HR=1.781, p=0.000), ICC drain losses (HR=1.337, p=0.000) and transfusion demands for red blood cells (HR=1.381, p=0.000) and platelets (HR=1.450, p=0.000) when compared to those discontinuing aspirin >7 days from surgery.

CONCLUSION

Late discontinuation of aspirin before combined coronary artery bypass graft and valve procedures results in greater rates of bleeding and transfusion requirements. Earlier discontinuation of aspirin results in no benefit in intermediate term survival.

Conduits Used in Coronary Artery Bypass Grafting: A Review of Morphological Studies

There is a significant variety of vascular conduits options for coronary bypass surgery. Adequate graft selection is the most important factor for the success of the intervention. To ensure durability, permeability, and bypass function, there must be a morphological similarity between the graft and the coronary artery. The objective of this review was to analyze the morphological characteristics of the grafts that are most commonly used in coronary bypass surgery and the coronary arteries that are most frequently occluded. We included clinical information regarding the characteristics that determine the behavior of the grafts and its permeability over time. Currently, the internal thoracic artery is the standard choice for bypass surgery because of the morphological characteristics of the wall that makes less prone to developing atherosclerosis and hyperplasia. The radial and right gastroepiploic arteries are the following second and third best options, respectively. The ulnar artery is the preferred choice when other conduits are not feasible.

Aspirin in the perioperative period: a review of the recent literature

PURPOSE OF REVIEW

The indications for aspirin (ASA) for both primary and secondary prevention of thrombotic events continue to evolve. We review some of these indications and the recent literature regarding the perioperative administration of ASA.

RECENT FINDINGS

ASA for primary prevention of cardiac ischemia, stroke, cancer, and death remains controversial. When used for primary prevention, ASA may be safely discontinued perioperatively. Patients with coronary or carotid artery stents should continue to receive ASA perioperatively. For patients with ischemic heart disease currently receiving ASA for secondary prevention of cardiac ischemia and stroke undergoing general surgery, orthopedic surgery, ophthalmological surgery, cardiovascular surgery, major vascular surgery, or a urological procedure, continuation of ASA is probably well tolerated, but further study is required. There is no indication to initiate ASA perioperatively in patients with stable ischemic heart disease as the risks outweigh the benefits. Until further data become available, decisions regarding the perioperative continuation of ASA should be made on a case-by-case risk-benefit analysis.

SUMMARY

The continuation or discontinuation of ASA perioperatively remains a complicated issue. Further, well designed trials are needed for additional clarification.

Pulmonary artery catheter

Since its inception, the pulmonary artery catheter has enjoyed widespread use in both medical and surgical critically ill patients. It has also endured criticism and skepticism about its benefit in these patient populations. By providing information such as cardiac output, mixed venous oxygen saturation, and intracardiac pressures, the pulmonary artery catheter may improve care of the most complex critically ill patients in the intensive care unit and the operating room. With its ability to transduce pressures through multiple ports, one of the primary clinical uses for pulmonary artery catheters is real-time intracardiac pressure monitoring. Correct interpretation of the waveforms is essential to confirming correct placement of the catheter to ensure accurate data are recorded. Major complications related to catheter placement are infrequent, but misinterpretation of monitored data is not uncommon and has led many to question the utility of the pulmonary artery catheter. The evidence to date suggests that the use of the catheter does not change mortality in many critically ill patients and may expose these patients to a higher rate of complications. However, additional clinical trials are needed, particularly in the most complex critically ill patients, who have generally been excluded from many of the research trials performed to date.

Perioperative management of combined carotid and coronary artery bypass grafting procedures

The objective of this review is to provide a high level overview on current thinking for treatment of patients with combined carotid and coronary artery disease given that these patients are at higher risk of adverse cardiac events, stroke, and death. This review discusses (1) the current literature addressing perioperative stroke risk in the setting of coronary artery bypass graft, (2) the literature regarding different surgical approaches when both carotid and coronary revascularization are being considered, and (3) the data available to guide optimal management of this complex patient population to minimize complications regardless of the surgical approach taken.

Safety and Efficacy Outcomes of Preoperative Aspirin in Patients Undergoing Coronary Artery Bypass Grafting

Background:

The administration of aspirin is traditionally discontinued prior to coronary artery bypass grafting (CABG), given a potential risk of excessive postoperative bleeding. Few studies have previously suggested the benefits of continuing aspirin until the time of surgery. The primary aim of this review is to evaluate the effects of preoperative aspirin therapy on several clinically important outcomes in patients undergoing CABG.

Methods:

A meta-analysis of eligible studies of patients undergoing CABG, reporting preoperative aspirin in comparison with no aspirin/placebo and our outcomes, was carried out. The safety outcomes included postoperative bleeding, packed red blood cell (PRBC) transfusion requirements, and reoperation for bleeding. The efficacy outcomes included perioperative myocardial infarction (MI), cerebrovascular accidents (CVAs), and mortality.

Results:

In 8 randomized controlled trials (RCTs; n = 1538), preoperative aspirin increased postoperative bleeding (difference in means = 132.30 mL; 95 % confidence interval [CI] 47.10-217.51; P = .002), PRBC transfusion requirements (difference in means = 0.67 units; 95% CI 0.10-1.24; P = .02), and reoperation for bleeding (odds ratio [OR] = 1.76; 95% CI 1.05-2.93; P = .03). In 19 observational studies (n = 19551), preoperative aspirin increased postoperative bleeding (difference in means = 132.74 mL; 95% CI 45.77-219.72; P = .003) and PRBC transfusion requirements (difference in means = 0.19 units; 95% CI 0.02-0.35; P = .02) but not reoperation for bleeding (OR = 1.13; 95% CI 0.91-1.42; P = .27). Subgroup analyses for RCTs demonstrated that aspirin given at doses ≤ 100 mg/d might not increase the postoperative bleeding, and the dose of 325 mg/d might not be a cutoff value that has clinical and statistical significance. No statistically significant differences in the rate of perioperative MI, CVAs, or mortality were seen between the 2 groups.

Conclusions:

Preoperative aspirin therapy is associated with increased postoperative bleeding, PRBC transfusion requirements, and reoperation for bleeding in patients undergoing CABG. Doses lower than 100 mg/d may minimize the risk of bleeding. Additional RCTs are needed to assess the effects of preoperative aspirin on the safety and efficacy outcomes in patients undergoing CABG.

Dual anti-platelet therapy after coronary artery bypass grafting: is there any benefit? A systematic review and meta-analysis

BACKGROUND

Anti-platelet therapy is an important component of medical therapy post coronary artery bypass grafting (CABG). While aspirin administration is a Class I indication after CABG, the benefit of concomitant clopidogrel is a controversial issue.

METHODS

We searched OVID Medline, Cochrane, Scopus, and EMBASE for randomized control trials and observational studies comparing aspirin ± placebo to aspirin + clopidogrel after CABG.

RESULTS

Eleven articles (five randomized control trials and six observational studies) including 25,728 patients met inclusion criteria. Early saphenous vein graft occlusion was reduced with the use of dual anti-platelet therapy (risk ratio (RR) = 0.59, 95% CI 0.43-0.82, p = 0.02). In-hospital or 30-day mortality was lower with aspirin + clopidogrel (0.8%) compared to aspirin alone (1.9%) (p < 0.0001), while risk of angina or perioperative myocardial infarction was comparable (RR = 0.60, 95% CI 0.31-1.14, p = 0.12). Patients treated with aspirin + clopidogrel demonstrated a trend towards a higher incidence of major bleeding episodes as compared to patients treated with aspirin alone (RR = 1.17, 95% CI 1.00-1.37, p = 0.05). In a pooled analysis of studies involving off-pump CABG compared to aspirin alone, dual anti-platelet therapy reduced the risk of perioperative myocardial infarction and saphenous graft occlusion by 68% (47% to 71%) and 55% (2% to 79%) respectively.

CONCLUSION

Dual anti-platelet therapy after CABG improved early saphenous vein graft patency, but may increase the risk of bleeding. The use of dual anti-platelet therapy appears to be most beneficial in patients undergoing off-pump CABG. Prospective randomized studies are necessary to determine whether this beneficial effect of dual therapy is also achieved in patients undergoing on pump CABG.

Implementation of an intraoperative glycemic control protocol for cardiac surgery in a high-acuity academic medical center: an observational study

STUDY OBJECTIVE

To examine the effect on morbidity and mortality of an established intraoperative insulin protocol in cardiac surgical patients.

DESIGN

Retrospective observational study.

SETTING

Single-center, 782 bed, metropolitan academic hospital.

PATIENTS

1,616 adult patients undergoing cardiac surgical procedures with cardiopulmonary bypass (CPB).

INTERVENTIONS

An intraoperative, intravenous (IV) insulin protocol designed to maintain blood glucose values less than 150 mg/dL was implemented.

MEASUREMENTS

Blood glucose was evaluated on entry to the operating room, every 30 minutes during CPB, and at least once after discontinuation of CPB. Blood glucose values were followed postoperatively, as dictated by institutional policy.

MAIN RESULTS

Intraoperative predictors of 30-day mortality using multivariate logistic regression included hyperglycemia on initiation of CPB (OR 1.0, P = 0.05). The strongest predictor of 30-day mortality was the development of postoperative renal failure requiring hemodialysis (OR 3.26, P = 0.001).

CONCLUSIONS

Implementation of an intraoperative IV insulin protocol, while associated with improved glycemic control, was not associated with improved outcomes. While improved glycemic control on initiating CPB was associated with decreased 30-day mortality, the effect was small. Implementation of our insulin protocol was highly associated with decreased renal failure postoperatively. Further prospective studies are warranted to better establish causality.

Myocardial Revascularization in New York State: Variations in the PCI-to-CABG Ratio and Their Implications

BACKGROUND

During the past 2 decades, percutaneous coronary intervention (PCI) has increased dramatically compared with coronary artery bypass grafting (CABG) for patients with coronary artery disease. However, although the evidence available to all practitioners is similar, the relative distribution of PCI and CABG appears to differ among hospitals and regions.

METHODS AND RESULTS

We reviewed the published data from the mandatory New York State Department of Health annual cardiac procedure reports issued from 1994 through 2008 to define trends in PCI and CABG utilization in New York and to compare the PCI/CABG ratios in the metropolitan area to the remainder of the State. During this 15-year interval, the procedure volume changes for CABG, for all cardiac surgeries, for non-CABG cardiac surgeries, and for PCI for New York State were -40%, -20%, +17.5%, and +253%, respectively; for the Manhattan programs, the changes were similar as follows: -61%, -23%, +14%, and +284%. The average PCI/CABG ratio in New York State increased from 1.12 in 1994 to 5.14 in 2008; however, in Manhattan, the average PCI/CABG ratio increased from 1.19 to 8.04 (2008 range: 3.78 to 16.2). The 2008 PCI/CABG ratios of the Manhattan programs were higher than the ratios for New York City programs outside Manhattan, in Long Island, in the northern counties contiguous to New York City, and in the rest of New York State; their averages were 5.84, 5.38, 3.31, and 3.24, respectively. In Manhattan, a patient had a 56% greater chance of receiving PCI than CABG as compared with the rest of New York State; in one Manhattan program, the likelihood was 215% higher.

CONCLUSIONS

There are substantial regional and statewide differences in the utilization of PCI versus CABG among cardiac centers in New York, possibly related to patient characteristics, physician biases, and hospital culture. Understanding these disparities may facilitate the selection of the most appropriate, effective, and evidence-based revascularization strategy. (J Am Heart Assoc. 2012;1:e001446 doi: 10.1161/JAHA.112.001446.).