Outcome of Early Revascularization Surgery in Patients with ST-Elevation Myocardial Infarction

Does Timing of Coronary Artery Bypass Grafting after ST-Elevation Myocardial Infarction Impact Early- and Long-Term Outcomes?

BACKGROUND

 The optimal timing of surgical revascularization after ST-elevation myocardial infarction (STEMI) is controversial, with some suggesting higher mortality rates in patients undergoing early surgery. The aim of the study is to determine the effect of the timing of surgical revascularization on 30-day mortality and long-term outcomes in these patients.

METHODS

 Retrospective single-center analysis of patients with STEMI undergoing coronary artery bypass grafting (CABG) between January 2008 and December 2019 at our institution. The cohort was split into three groups based on time from symptom onset until surgical revascularization (Group 1: <12 hours, Group 2: 12-72 hours, Group 3: >72 hours). Statistical analyses were performed with and without patients in cardiogenic shock. Primary outcomes were 30-day mortality and 10-year survival.

RESULTS

 During the study period, 437 consecutive patients underwent surgical revascularization in the setting of STEMI. The mean age was 67.0 years, 96 (22.0%) patients were female, and 281 (64.3%) patients underwent off-pump CABG. The overall 30-day mortality including patients with cardiogenic shock was 12.8%. The 30-day mortality was 16.1, 13.9, and 9.3% in Groups 1, 2, and 3 (p = 0.31), whereas 10-year survival was 48.5, 57.3, and 54.9% (log-rank: p = 0.40). After exclusion of patients in cardiogenic shock, there was no difference between the three groups in 30-day and 10-year mortality. Timing of surgery had no influence on early- and long-term survival.

CONCLUSION

 In patients with STEMI, early surgical revascularization achieved similar early- and long-term survival rates compared with a delayed surgical revascularization strategy. Hence, when indicated, an early CABG strategy has no disadvantages in comparison to a delayed strategy.

Coronary artery bypass grafting after acute ST-elevation myocardial infarction

OBJECTIVES

The study objectives were to describe the trends and outcomes of isolated coronary artery bypass grafting after ST-elevation myocardial infarction using a nationwide database.

METHODS

We queried the 2002-2016 National Inpatient Sample database for hospitalized patients with ST-elevation myocardial infarction who underwent isolated coronary artery bypass grafting. We report temporal trends, predictors, and outcomes of coronary artery bypass grafting in the early (2002-2010) and recent (2011-2016) cohorts.

RESULTS

Of 3,347,470 patients hospitalized for ST-elevation myocardial infarction, 7.7% underwent isolated coronary artery bypass grafting. The incidence of isolated coronary artery bypass grafting after ST-elevation myocardial infarction decreased over time (9.2% in 2002 vs 5.5% in 2016, P_trend < .001), whereas perioperative crude in-hospital mortality did not change (5.1% in 2002 vs 4.2% in 2016, P_trend = .66), coinciding with an increase in the burden of comorbidities. There was an increase in performing isolated coronary artery bypass grafting on hospitalization day 3 or more, as well as an increase in the use of mechanical support devices and precoronary artery bypass grafting percutaneous coronary intervention. In the early cohort, isolated coronary artery bypass grafting on days 1 and 2 was associated with higher in-hospital mortality. In the recent cohort, coronary artery bypass grafting on day 2 had similar in-hospital mortality compared with day 3 or more and lower rates of acute kidney injury, ischemic stroke, ventricular arrhythmia, and length of hospital stay.

CONCLUSIONS

In this nationwide analysis, there has been a decline in the use of isolated coronary artery bypass grafting after ST-elevation myocardial infarction. Isolated coronary artery bypass grafting on day 1 was performed in sicker patients and was associated with higher in-hospital mortality than coronary artery bypass grafting performed on day 3 or more. In the recent cohort, isolated coronary artery bypass grafting on day 2 had similar in-hospital mortality compared with day 3 or more.

Appropriate Timing of Coronary Artery Bypass Graft Surgery for Acute Myocardial Infarction Patients: A Meta-Analysis

Background

Currently, percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) are commonly used in the treatment of coronary atherosclerotic heart disease. But the optimal timing for CABG after acute myocardial infarction (AMI) is still controversial. The purpose of this article was to evaluate the optimal timing for CABG in AMI.

Methods

We searched the PubMed, Embase, and Cochrane library databases for documents that met the requirements. The primary outcome was in-hospital mortality. The secondary outcomes were perioperative myocardial infarction (MI) incidence and cerebrovascular accident incidence.

Results

The search strategy produced 1,742 studies, of which 19 studies (including data from 113,984 participants) were included in our analysis. In total, 14 studies compared CABG within 24 h with CABG late 24 h after AMI and five studies compared CABG within 48 h with CABG late 48 h after AMI. The OR of in-hospital mortality between early 24 h CABG and late 24 h CABG group was 2.65 (95%CI: 1.96 to 3.58; P < 0.00001). In the undefined ST segment elevation myocardial infarction (STEMI)/non-ST segment elevation myocardial infarction (NSTEMI) subgroup, the mortality in the early 24 h CABG group (OR: 3.88; 95%CI: 2.69 to 5.60; P < 0.00001) was significantly higher than the late 24 h CABG group. Similarly, in the STEMI subgroup, the mortality in the early 24 h CABG group (OR: 2.62; 95% CI: 1.58 to 4.35; P = 0.0002) was significantly higher than that in the late 24 h CABG group. However, the mortality of the early 24 h CABG group (OR: 1.24; 95%CI: 0.83 to 1.85; P = 0.29) was not significantly different from that of the late 24 h CABG group in the NSTEMI group. The OR of in-hospital mortality between early 48 h CABG and late 48 h CABG group was 1.91 (95%CI: 1.11 to 3.29; P = 0.02). In the undefined STEMI/NSTEMI subgroup, the mortality in the early 48 h CABG group (OR: 2.84; 95%CI: 1.31 to 6.14; P < 0.00001) was higher than the late 48 h CABG group. The OR of perioperative MI and cerebrovascular accident between early CABG and late CABG group were 1.38 (95%CI: 0.41 to 4.72; P = 0.60) and 1.31 (95%CI: 0.72 to 2.39; P = 0.38), respectively.

Conclusion

The risk of early CABG could be higher in STEMI patients, and CABG should be delayed until 24 h later as far as possible. However, the timing of CABG does not affect mortality in NSTEMI patients. There was no statistical difference in perioperative MI and cerebrovascular accidents between early and late CABG.

Meta-Analysis of Nonrandomized Studies to Assess the Optimal Timing of Coronary Artery Bypass Grafting After Acute Myocardial Infarction

The optimal timing of coronary artery bypass grafting (CABG) in patients after an acute myocardial infarction (MI) is unknown. We performed a systematic review and meta-analysis of studies comparing mortality rates in patients who underwent CABG at different time intervals after acute MI. Bias assessments were completed for each study, and summary of proportions of all-cause mortality were calculated based on CABG at various time intervals after MI. A total of 22 retrospective studies, which included a total of 137,373 patients were identified. The average proportion of patients who died when CABG was performed within 6 hours of MI was 12.7%, within 6 to 24 hours of MI was 10.9%, within 1 day of MI was 9.8%, any time after 1 day of MI was 3.0%, within 7 days of MI was 5.9%, and any time after 7 days of MI was 2.7%. Interstudy heterogeneity, assessed using I² values, showed significant heterogeneity in death rates within subgroups. Only 1 study accounted for immortal time bias, and there was a serious risk of selection bias in all other studies. Confounding was found to be a serious risk for bias in 55% of studies because of a lack of accounting for type of MI, MI severity, or other verified cardiac risk factors. The current publications comparing timing of CABG after MI is at serious risk of bias because of patient selection and confounding, with heterogeneity in both study populations and intervention time intervals.

The timing of surgical revascularisation in acute myocardial infarction: when should we intervene?

INTRODUCTION

Coronary artery bypass grafting (CABG) is a crucial intervention in acute myocardial infarction (AMI), particularly when AMI is not amenable for management with primary percutaneous coronary intervention (PCI). To optimise outcome in these patients, surgical teams must consider a host of predictive factors, with the most prominent being the timing of CABG. Despite numerous studies exploring timing of CABG following AMI in the past, optimal surgical timing remains controversial. The mortality rates vary with timing of CABG, but confounding factors such as age, impaired pulmonary function, renal insufficiency, and poor left ventricular function may contribute to varied outcomes reported.

EVIDENCE ACQUISITON

An electronic literature search of articles that discussed acute myocardial presentation and urgent in-patient or elective CABG was conducted.

EVIDENCE SYNTHESIS

The evidence was synthesised based on each reported article and their outcomes.

CONCLUSIONS

Current literature suggests multiple factors can guide CABG timing including, type of AMI at initial presentation, distinctive pathological status and patient characteristics. Thus, there is a need for large, multi-centre studies to identify optimal CABG timing in complex coronary artery disease or failed PCI in patients with AMI. Future guidelines should emphasise patient cohorts by taking their risk factors into consideration. As such, a need for greater cardiac screening methods and development of scoring systems can aid in the optimisation of CABG timing.

Preoperative troponin levels and outcomes of coronary surgery following myocardial infarction

BACKGROUND

This study evaluates the impact of peak preoperative troponin level on outcomes of coronary artery bypass grafting (CABG) for non-ST-elevation myocardial infarction (NSTEMI).

METHODS

This was a retrospective review of patients undergoing isolated CABG from 2011 to 2018 with the presentation of NSTEMI. Patients were stratified into low- and high-risk groups based on median preoperative peak troponin (1.95 ng/dl). Major adverse cardiac and cerebrovascular events (MACCE) and mortality were compared. Multivariable analysis was performed to model risk factors for MACCE and mortality.

RESULTS

This study included 1211 patients, 607 low-risk (≤1.95 ng/dl) and 604 high-risk (>1.95 ng/dl). Patients were well-matched with respect to age and comorbidity. High-risk patients had lower median preoperative ejection fraction (46.5% [interquartile range {IQR}: 35.0%-55.0%] vs. 53.0% [IQR: 40.0%-58.0%]) and higher incidence of preoperative intra-aortic balloon pump (15.9% vs. 8.73%). Intensive care unit and hospital length of stay were longer in the high-risk group, but increasing troponin level was not associated with prolonged intensive care or hospital length of stay (>4 and >14 days, respectively) after risk adjustment. Postoperative complications and 30-day, 1- and 5-year rates of both MACCE and survival were similar between groups. Peak troponin greater than 1.95 ng/dl was not associated with increased hazards for MACCE, mortality, or readmission in multivariable modeling. In subanalysis, neither increasing troponin as a continuous variable nor peak troponin greater than 10.00 ng/ml were associated with increased hazards for these outcomes.

CONCLUSIONS

Preoperative troponin levels do not appear to be predictive of short- or long-term outcomes following CABG, and clinical decisions regarding surgical revascularization should not be dictated by these measurements.

Utility of logistic clinical SYNTAX score in prediction of in-hospital mortality in ST-elevation myocardial infarction patients undergoing emergent coronary artery bypass graft surgery

AIM

The logistic clinical SYNTAX score (log CSS) is a combined risk scoring system including clinical and anatomic parameters; it has been found to be effective for the prediction of mortality in patients with ST-elevation myocardial infarction (STEMI). Coronary artery bypass grafting (CABG) in the primary treatment of acute myocardial infarction is still debated. In the present study, we aimed to evaluate the utility of log CSS to stratify the risk of in-hospital mortality in acute STEMI patients undergoing emergent CABG for primary revascularization.

METHOD

In total, 88 consecutive patients with acute STEMI, who did not qualify for primary percutaneous coronary intervention and required emergent CABG were included in our study. Nine of 88 patients died during hospitalization. The study population was divided into two groups as in-hospital survivors and non-survivors. Log CSS and SYNTAX score (SS) were calculated for both groups and two groups were compared in terms of demographics, preoperative, intraoperative, postoperative characteristics, SS and log CSS.

RESULTS

Log CSS was found to be an independent predictor of in-hospital mortality, log CSS > 10.5 had 89% sensitivity, 81% specificity (area under the curve: 0.927; 95% confidence interval: 0.855-0.993). Moreover, peak troponin level was an independent predictor of in-hospital mortality. Glucose level, cardiopulmonary resuscitation before operation, glomerular filtration rate, left ventricular ejection fraction, and Killip class were significantly associated with in-hospital mortality.

CONCLUSION

Log CSS may improve the accuracy of risk assessment in patients who are undergoing emergent CABG for primary revascularization of STEMI.

Risk of Ischemic Stroke After Acute Myocardial Infarction in Patients Undergoing Coronary Artery Bypass Graft Surgery

Only sparse epidemiological data are available regarding the risk of ischemic stroke (IS) after coronary artery bypass surgery (CABG). Here we aimed to describe the incidence and predictors of IS associated with CABG performed after acute myocardial infarction (AMI), as well as trends over time. We analyzed data for 248,925 unselected AMI patients. We separately analyzed groups of patients who underwent CABG early or late after the index infarction. IS incidence rates per year at risk were 15.8% (95% confidence interval, 14.5–17.1) and 10.9% (10.6–11.2), respectively, among patients with and without CABG in the early cohort, and 4.0% (3.5–4.5) and 2.3% (2.2–2.3), respectively, among patients with and without CABG in the late cohort. Predictors of post-AMI IS included prior IS, CABG, prior atrial fibrillation, prior hemorrhagic stroke, heart failure during hospitalization, older age, diabetes mellitus, and hypertension. Reduced IS risk was associated with use of statins and P2Y12 inhibitors. IS incidence markedly decreased among patients who did not undergo CABG, while no such reduction over time occurred among those who underwent CABG. This emphasizes the need to optimize modifiable risk factors and to consistently use treatments that may reduce IS risk among CABG patients.

Training in Coronary Artery Bypass Surgery: Tips and Tricks of the Trade

Coronary artery bypass is often the first procedure cardiac surgeons are confronted with during their residencies. This article discusses the surgical steps and the potential difficulties encountered during this procedure and how they can be solved. The "point of view" of an experienced surgeon is provided to the trainees and to the readers.

Optimal Timing of Surgical Revascularization for Myocardial Infarction and Left Ventricular Dysfunction

Background:

The optimal timing of surgical revascularization for patients presenting with ST-segment elevation myocardial infarction (STEMI) and impaired left ventricular function is not well established. This study aimed to examine the timing of surgical revascularization after STEMI in patients with ischemic heart disease and left ventricular dysfunction (LVD) by comparing early and late results.

Methods:

From January 2003 to December 2013, there were 2276 patients undergoing isolated coronary artery bypass grafting (CABG) in our institution. Two hundred and sixty-four (223 male, 41 females) patients with a history of STEMI and LVD were divided into early revascularization (ER, <3 weeks), mid-term revascularization (MR, 3 weeks to 3 months), and late revascularization (LR, >3 months) groups according to the time interval from STEMI to CABG. Mortality and complication rates were compared among the groups by Fisher's exact test. Cox regression analyses were performed to examine the effect of the time interval of surgery on long-term survival.

Results:

No significant differences in 30-day mortality, long-term survival, freedom from all-cause death, and rehospitalization for heart failure existed among the groups (P > 0.05). More patients in the ER group (12.90%) had low cardiac output syndrome than those in the MR (2.89%) and LR (3.05%) groups (P = 0.035). The mean follow-up times were 46.72 ± 30.65, 48.70 ± 32.74, and 43.75 ± 32.43 months, respectively (P = 0.716). Cox regression analyses showed a severe preoperative condition (odds ratio = 7.13, 95% confidence interval 2.05–24.74, P = 0.002) rather than the time interval of CABG (P > 0.05) after myocardial infarction was a risk factor of long-term survival.

Conclusions:

Surgical revascularization for patients with STEMI and LVD can be performed at different times after STEMI with comparable operative mortality and long-term survival. However, ER (<3 weeks) has a higher incidence of postoperative low cardiac output syndrome. A severe preoperative condition rather than the time interval of CABG after STEMI is a risk factor of long-term survival.

Admission hyperglycemia is associated with poor outcome after emergent coronary bypass grafting surgery

PURPOSE

Hyperglycemia during or after cardiac surgery is a common finding that is associated with poor outcome. Very few data, however, are available regarding a correlation between admission blood glucose and outcomes after coronary artery bypass grafting (CABG). Thus, the goal of the current study was to examine the relationship between admission blood glucose and outcome after emergency CABG surgery.

MATERIALS AND METHODS

A retrospective analysis to evaluate whether admission hyperglycemia associated with increased morbidity or mortality was performed in patients after emergency CABG surgery. The records of all the patients undergoing emergency CABG surgery between January 1999 and December 2010 at the University of Virginia Health System were reviewed. Postoperative in-hospital mortality and complications were considered as study end points.

RESULTS

A total of 240 patients met the final inclusion criteria. Overall mortality was 14.1%. The median admission blood glucose in patients who died 7.4 (interquartile range, 5.9-10.1) mmol/L was significantly higher compared with survivors 6.1 (interquartile range, 5.4-7.2; P<.01). Furthermore, 59% of the patients who died had admission blood glucose levels higher than 6.6 mmol/L, whereas only 35% of the patients who survived had similar blood glucose levels (P=.01). On multivariable analysis, admission blood glucose was identified as an independent risk factor for death after emergency CABG (P=.01; odds ratio, 1.16; 95% confidence interval, 1.04-1.29). Admission blood glucose was further identified as independently associated with increased risk for a composite outcome of death, postoperative renal failure or stroke (P=.01; odds ratio, 1.14; 95% confidence interval, 1.03-1.27).

CONCLUSIONS

Our study shows for the first time that admission blood glucose is correlated with increased morbidity and mortality among patients undergoing emergency CABG surgery.