Early versus delayed coronary artery bypass graft surgery for patients with non-ST elevation myocardial infarction

Pretreatment with a P2Y12 receptor inhibitor and delay to coronary artery bypass surgery in patients with non-ST segment elevation acute coronary syndrome

BACKGROUND

2020 ESC guidelines for non-ST elevation acute coronary syndromes (NSTE-ACS) recommend against the pretreatment with P2Y12 receptor inhibitors (P2Y12i) in patients undergoing early invasive management (<24 h). The rationale is, in part, to prevent bleeding complications and the delay of coronary artery bypass graft surgery (CABG) in patients with suitable coronary anatomy. This study aimed to analyze the theoretical impact of pretreatment with a P2Y12i on delay to CABG surgery in a real-world population with NSTE-ACS.

METHODS

Single-center retrospective cohort of consecutive patients with NSTE-ACS undergoing invasive evaluation in 2019. Those with previous CABG or nonobstructive coronary disease were excluded.

RESULTS

The total cohort included 262 patients (mean age 68±12 years, 69% male, 15% with unstable angina and mean GRACE score 134±35). Median time from FMC to angiography was 2 (1-4) days. Overall, 168 (64%) patients underwent percutaneous coronary intervention, 47 (18%) were proposed for CABG and the remainder received conservative management. All patients considered for CABG received pretreatment with P2Y12i (clopidogrel or ticagrelor). The median time from angiography to CABG was 12 (7-15) days. Six patients experienced recurrent angina (13%) and 2 (4%) died before surgery due to refractory ventricular fibrillation. Those who underwent CABG under P2Y12i effect were more likely to receive blood and platelets transfusions (64.7% vs. 28.6%, P=0.017 and 82.4% vs. 21.4%, P<0.001, respectively), although there were no differences regarding major bleeding.

CONCLUSIONS

Pretreatment with P2Y12i was a potential but not the sole driver of CABG delay in our cohort. Adopting the new recommendations of withholding pretreatment might decrease this delay, but other factors must be considered.

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.

Treatment Bias in Management of HIV Patients Admitted for Acute Myocardial Infarction: Does It Still Exist?

INTRODUCTION

Previous studies have reported lower rates of coronary angiography and revascularization, and significantly higher mortality among patients infected with human immunodeficiency virus (HIV) presenting with acute myocardial infarction (AMI). This observational study was designed to evaluate characteristics and inpatient outcomes of patients with seropositive HIV infection presenting with AMI.

METHODS

Using the National Inpatient Sample (NIS) database, we identified patients (admissions) with a primary diagnosis of myocardial infarction and a co-occurring HIV. We described baseline characteristics and outcomes. Our primary outcomes of interest were prevalence of coronary angiography, revascularization (percutaneous coronary intervention (PCI) or CABG), and mortality.

RESULTS

From 2010 to 2014, of about 2,977,387 patients with a primary diagnosis of AMI, 10,907 (0.4%) were HIV seropositive. Patients with HIV were younger and more likely to be African American or Hispanic. Coronary angiography and revascularization were performed more frequently in the HIV population. The higher prevalence of revascularization was driven by a higher incidence of PCI. In a multivariable model, patients with HIV were no more likely to undergo revascularization than the general population. This was also the case for PCI. Unadjusted all-cause mortality was lower among patients with HIV. After controlling for confounders, this finding was not significant (OR 0.97, 95% CI 0.75-1.25, p = 0.79). The length of stay between both groups was comparable.

CONCLUSION

In this current analysis, we did not note any treatment bias or difference in the rate of in-hospital total mortality for HIV-seropositive patients presenting with AMI compared with the general population.