Antiplatelet Therapy and Coronary Artery Bypass Grafting: Analysis of Current Evidence With a Focus on Acute Coronary Syndrome

Optimal Revascularization Timing of Coronary Artery Bypass Grafting in Acute Myocardial Infarction

INTRODUCTION

Acute myocardial infarction (AMI) is a major global health concern. However, the optimum timing of coronary artery bypass grafting (CABG) in AMI patients remains controversial. This study investigated the optimal timing of CABG and its impact on postoperative outcomes. We hypothesized that determining the optimal timing of CABG could positively impact postoperative outcomes.

METHODS

We conducted a nationwide retrospective analysis of the National Health Insurance Service of Korea database, focusing on 1 705 843 adult AMI patients diagnosed between 2007 and 2018 who underwent CABG within 1 year of diagnosis. Patients were categorized based on CABG timing. Primary endpoints included cohort identification and the time interval from AMI diagnosis to CABG. Secondary endpoints encompassed major adverse cardiac and cerebrovascular events (MACCEs) and the impact of postoperative medications.

RESULTS

Of the patients, 20 172 underwent CABG. Surgery within 24 h of AMI diagnosis demonstrated the most favorable outcomes, reducing cardiac death, myocardial infarction recurrence, and target vessel revascularization. Delayed CABG within 3 days also outperformed surgery within 1-2 days post-AMI. Additionally, postoperative aspirin use was associated with improved MACCE outcomes.

CONCLUSION

CABG within 24 h of AMI diagnosis was associated with significantly minimized myocardial injury, emphasizing the critical role of rapid revascularization. Delayed CABG within 3 days related to better outcomes compared with that of surgery within 1-2 days. These findings provide evidence-based recommendations for optimizing CABG timing in AMI patients, consequentially reducing morbidity and mortality.

Efficacy and Safety of Long-Term Dual Antiplatelet Therapy: A Systematic Review and Meta-Analysis

BACKGROUND

Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor is a standard therapy in patients with ischemic vascular diseases (IVD) including coronary artery, cerebrovascular and peripheral arterial diseases, although the optimal duration of this treatment is still debated. Previous meta-analyses reported conflicting results about the effects of long-term and short-term as well as non-DAPT use in various clinical settings. Herein, we conducted a comprehensive meta-analysis to assess the efficacy and safety of different durations of DAPT.

METHODS

We reviewed relevant articles and references from database, which were published prior to April 2023. Data from prospective studies were processed using RevMan5.0 software, provided by Cochrane Collaboration and transformed using relevant formulas. The inclusion criteria involved randomization to long-term versus short-term or no DAPT; the endpoints included at least one of total or cardiovascular (CV) mortalities, IVD recurrence, and bleeding.

RESULTS

A total of 34 randomized studies involving 141 455 patients were finally included. In comparison with no or short-term DAPT, long-term DAPT reduced MI and stroke, but did not reduce the total and CV mortalities. Meanwhile, bleeding events were increased, even though intracranial and fatal bleedings were not affected. Besides, the reduction of MI and stroke recurrence showed no statistical significance between long-term and short-term DAPT groups.

CONCLUSION

Long-term DAPT may not reduce the mortality of IVD besides increasing bleeding events, although reduced the incidences of MI and stroke early recurrence to a certain extent and did not increase the risk of fatal intracranial bleeding.

Impact of provincial and national implementation strategies on P2Y12 inhibitor utilization for acute coronary syndrome in the elderly: an interrupted time series analysis from 2008 to 2018

Background

Guidelines recommend both acetylsalicylic acid and ticagrelor following acute coronary syndrome (ACS), but appropriate prescription practices lag. We analyzed the impact of government medication approval, national guideline updates, and publicly funded drug coverage plans on P2Y12 inhibitor utilization.

Methods

Accessing provincial databases, we obtained data for elderly ACS patients in Ontario, Canada, between 2008 and 2018. Using interrupted-time series with descriptive statistics and segmented regression analysis, we evaluated types of P2Y12 inhibitors prescribed at discharge and changes to their utilization in patients managed with percutaneous intervention (PCI), coronary artery bypass grafting (CABG) or medically, following national antiplatelet therapy guidelines (by the Canadian Cardiovascular Society), ticagrelor’s national approval by Health Canada, and ticagrelor’s coverage by a publicly funded medication plan.

Results

We included 114,142 patients (49.4%-PCI; mean age 75.71±6.94 and 62.3% male and 7.7%-CABG; mean age 74.11±5.63 and 73.5% male).

Among PCI patients, clopidogrel utilization declined monthly after 2010 national guidelines were published (p<0.0001) and within the first month after ticagrelor’s national approval by Health Canada (p=0.03). Among PCI patients, ticagrelor utilization increased within the first month (p<0.0001) and continued increasing monthly (p<0.0001) after its coverage by a publicly funded medication plan. Among PCI patients, clopidogrel utilization declined within the first month (p=0.003) and ticagrelor utilization increased monthly (p=0.05) after 2012 CCS guidelines.

Among CABG patients, ticagrelor’s coverage was associated with a monthly increase in its utilization (p<0.0001).

Conclusion

National guideline updates and drug coverage by a publicly funded medication plan significantly improved P2Y12 inhibitor utilization. Barriers to appropriate antiplatelet therapy in the surgical population must be explored.

[Coronary artery bypass grafting in myocardial infarction and unstable angina pectoris: in-hospital outcomes. Part 2]

AIM

To assess in-hospital outcomes of coronary artery bypass grafting in patients with acute coronary syndrome, depending on the presence or absence of myocardial infarction.

PATIENTS AND METHODS

Over the period from 2017 to 2018 within the framework of a single-centre register, the study enrolled a total of 166 consecutive patients admitted with non-ST segment elevation acute coronary syndrome and subjected to coronary artery bypass grafting. Depending on the outcome of acute coronary syndrome, the patients were divided into 2 groups: Group One included 98 (59%) patients with unstable angina pectoris and Group Two comprised 68 (41%) patients with myocardial infarction, who underwent surgery at an average of 16 (11; 20) days after manifestation of the clinical signs of myocardial infarction. The endpoints of the study were major adverse cardiovascular events during the in-hospital period: death, myocardial infarction, acute cerebral circulation impairment/transitory ischaemic attack, repeat revascularization, septic complications, multiple organ failure syndrome, wound infectious complications, requirement for repeated surgical debridement, remediastinotomy due to haemorrhage, the frequency of extracorporeal membrane oxygenation and renal replacement therapy.

RESULTS

The mortality rate in the compared groups was similar: 3% (n=3) and 3% (n=2), respectively. Perioperative myocardial infarction occurred in 1 (1%) patient of the first group, with no cases of this complication observed in the second group. The frequency of reoperations due to haemorrhage in the early postoperative period in the group of unstable angina pectoris amounted to 3% (n=3) and was associated with administration of dual antithrombotic therapy, with no cases of this complication in the group of myocardial infarction. Wound complication in the second group were observed in 7.6% (n=5) and in the first group in 4% (n=4) (p=0.33). The differences turned out to be statistically insignificant for such postoperative complications as multiple organ failure syndrome, requirement for repeated surgical debridement, renal replacement therapy, and extracorporeal membrane oxygenation. The residual SYNTAX Score in the group of myocardial infarction amounted to 2.3±2.8, whereas in the group of unstable angina pectoris to 2.3±3, thus suggesting complete revascularization in the total sample of patients with acute coronary syndrome. The average length of hospital stay (including the postoperative period) in the first group amounted to 26.3±6.6 days and in the second group to 27.4±7.2 days (p=0.53). The postoperative bed-day in the group with unstable angina pectoris was 12.6±3.2 and in the myocardial infarction group - 14.9±5.3 (p=0.06).

CONCLUSION

The obtained in-hospital outcomes suggest that coronary artery bypass grafting may be an efficient and safe method of complete revascularization for patients with non-ST-elevation acute coronary syndrome, including that resulting in myocardial infarction, performed averagely on day 16 (11; 20) after the onset of clinical manifestations of myocardial infarction.

Re-evaluating the Role of CABG in Acute Coronary Syndromes

PURPOSE OF REVIEW

The use of coronary artery bypass grafting (CABG) in patients with acute coronary syndrome (ACS) has markedly declined during the past decade, with an increase in the use of percutaneous coronary intervention (PCI). However, long-term data continues to show survival advantages for patients undergoing CABG over PCI. We describe the current indications for and outcomes of CABG in patients who present with ACS.

RECENT FINDINGS

Real-world studies demonstrate better long-term outcomes with CABG than with PCI after NSTE-ACS. Staged CABG after culprit-vessel PCI for STEMI is also a feasible option in certain patients. In patients presenting with ACS and cardiogenic shock who are treated with CABG, the use of mechanical circulatory support has produced a limited but significant reduction in mortality. The optimal revascularization strategy after ACS depends on many variables. The pre-eminent factor in selecting the best mode of revascularization and improving outcomes is careful patient selection based on deliberation by an interdisciplinary heart team.

Antiplatelet therapy and coronary artery bypass grafting: a systematic review and network meta-analysis

OBJECTIVES

Acetylsalicylic acid (ASA) monotherapy is the standard of care after coronary artery bypass grafting (CABG), but the benefits of more intense antiplatelet therapy, specifically dual antiplatelet therapy (DAPT), require further exploration in CABG patients. We performed a network meta-analysis to compare the effects of various antiplatelet regimens on saphenous vein graft patency, mortality, major adverse cardiovascular events and bleeding among CABG patients.

METHODS

We searched Cochrane Central Register of Controlled Trials, Medical Literature Analysis and Retrieval Systems Online, Excerpta Medica Database, Cumulative Index to Nursing and Allied Health Literature, American College of Physicians Journal Club and conference proceedings for randomized controlled trials. Screening, data extraction, risk of bias assessment and Grading of Recommendations Assessment, Development and Evaluation were performed in duplicate. We conducted a random effect Bayesian network meta-analysis including both direct and indirect comparisons.

RESULTS

We included 43 randomized controlled trials studying 15 511 patients. DAPT with low-dose ASA and ticagrelor [odds ratio (OR) 2.53, 95% credible interval (CrI) 1.35–4.72; I2 = 55; low certainty] or clopidogrel (OR 1.56, 95% CrI 1.02–2.39; I2 = 55; very low certainty) improved saphenous vein graft patency when compared to low-dose ASA monotherapy. DAPT with low-dose ASA and ticagrelor was associated with lower mortality (OR 0.52, 95% CrI 0.30–0.87; I2 = 14; high certainty) and lower major adverse cardiovascular events (OR 0.63, 95% CrI 0.44–0.91; I2 = 0; high certainty) when compared to low-dose ASA monotherapy. Based on moderate certainty evidence, DAPT was associated with an increase in major bleeding.

CONCLUSIONS

Our results suggest that DAPT improves saphenous vein graft patency, mortality and major adverse cardiovascular event. As such, surgeons and physicians should consider re-initiating DAPT for acute coronary syndrome patients after their CABG, at the expense of an increased risk for major bleeding.

Clinical trial registration

International Prospective Register of Systematic Reviews ID Number CRD42019127695

Comparison of Preventive Cardiovascular Pharmacotherapy in Surgical vs Percutaneous Coronary Revascularization

Background

Data suggest that patients who undergo coronary artery bypass grafting (CABG) have a lower rate of secondary preventive cardiovascular pharmacotherapy use compared with patients who undergo percutaneous coronary intervention (PCI). This study sought to assess the rate of use of preventive pharmacotherapy at discharge in patients who underwent CABG vs PCI post–acute coronary syndrome (ACS).

Methods

A prospective cohort study was conducted at St Paul’s Hospital in Vancouver, Canada. Patients aged ≥ 18 years who presented with an ACS and underwent CABG or PCI between January and November 2018 were included. Data on preventive pharmacotherapy use and reasons for justified nonuse (eg, intolerance, contraindication) were collected.

Results

A total of 275 patients were included. Mean age was 65 years, and 83% were male. Overall, 141 patients (51%) underwent CABG and 134 patients (49%) underwent PCI. All patients received acetylsalicylic acid, but more patients who underwent CABG received 325 mg (vs 80-81 mg) compared to PCI (25% vs 1%, P < 0.01). Use of P2Y12 inhibitors was higher in patients who underwent PCI (primarily ticagrelor) compared with patients who underwent CABG (primarily clopidogrel) (99% vs 26%, P < 0.01). All patients who underwent CABG received a β-blocker vs 96% of patients who underwent PCI (P = 0.017). Use of angiotensin-modulating agents was higher in patients who underwent PCI (98% vs 65%, P < 0.01). Statin use was similar between groups (99% vs 99%, P = 0.96), but more patients who underwent PCI received maximum-dose therapy (89% vs 64%, P < 0.01).

Conclusions

Use of acetylsalicylic acid, β-blockers, and statins in patients post-ACS was high regardless of revascularization strategy, whereas P2Y12 inhibitors and angiotensin-modulating agents were underused in patients who underwent CABG even after adjusting for justified nonuse.