Network meta-analysis of antiplatelet therapy following coronary artery bypass grafting (CABG): none versus one versus two antiplatelet agents

Preventive medication efficacy after 1-year follow-up for graft failure in coronary artery bypass surgery patients: Bayesian network meta-analysis

To compare preventive medications against graft failures in coronary artery bypass graft surgery (CABG) patients after a 1-year follow-up. Systematic review with Bayesian network meta-analysis and meta-regression analysis. We searched PubMed, Scopus, and Web of Science databases in February 2023 for randomized controlled trials, comparing preventive medications against graft failure in CABG patients. We included studies that reported outcomes at 1 year after surgery. Our primary outcome was graft failure After screening 11,898 studies, a total of 18 randomized trials were included. Acetylsalicylic acid (ASA) [odds ratios (OR) 0.51, 95% credibility interval (CrI) 0.28-0.95, meta-regression OR 0.54, 95% CrI 0.26-1.00], Clopidogrel + ASA (OR 0.27, 95% CrI 0.09-0.76, meta-regression OR 0.28, 95% CrI 0.09-0.85), dipyridamole + ASA (OR 0.50, 95% CrI 0.30-0.83, meta-regression OR 0.49, 95% CrI 0.26-0.90), ticagrelor (OR 0.40, 95% CrI 0.16-1.00, meta-regression OR 0.43, 95% CrI 0.15-1.2), and ticagrelor + ASA (OR 0.26, 95% CrI 0.10-0.62, meta-regression OR 0.28, 95% CrI 0.10-0.68) were superior to placebo in preventing graft failure. Rank probabilities suggested the highest likelihood to be the most efficacious for ticagrelor + ASA [surface under the cumulative ranking (SUCRA) 0.859] and clopidogrel + ASA (SUCRA 0.819). The 95% CrIs of ORs for mortality, bleeding, and major adverse cardio- and cerebrovascular events (MACE) were wide. A trend towards increased bleeding risk and decreased MACE risk was observed when any of the medication regimens were used when compared to placebo. Sensitivity analysis excluding studies with a high risk of bias yielded equivalent results. Of the reviewed medication regimens, dual antiplatelet therapy combining ASA with ticagrelor or clopidogrel was found to result in the lowest rate of graft failures.

Graft Failure After Coronary Artery Bypass Grafting and Its Association With Patient Characteristics and Clinical Events: A Pooled Individual Patient Data Analysis of Clinical Trials With Imaging Follow-Up

BACKGROUND

Graft patency is the postulated mechanism for the benefits of coronary artery bypass grafting (CABG). However, systematic graft imaging assessment after CABG is rare, and there is a lack of contemporary data on the factors associated with graft failure and on the association between graft failure and clinical events after CABG.

METHODS

We pooled individual patient data from randomized clinical trials with systematic CABG graft imaging to assess the incidence of graft failure and its association with clinical risk factors. The primary outcome was the composite of myocardial infarction or repeat revascularization occurring after CABG and before imaging. A 2-stage meta-analytic approach was used to evaluate the association between graft failure and the primary outcome. We also assessed the association between graft failure and myocardial infarction, repeat revascularization, or all-cause death occurring after imaging.

RESULTS

Seven trials were included comprising 4413 patients (mean age, 64.4±9.1 years; 777 [17.6%] women; 3636 [82.4%] men) and 13 163 grafts (8740 saphenous vein grafts and 4423 arterial grafts). The median time to imaging was 1.02 years (interquartile range [IQR], 1.00-1.03). Graft failure occurred in 1487 (33.7%) patients and in 2190 (16.6%) grafts. Age (adjusted odds ratio [aOR], 1.08 [per 10-year increment] [95% CI, 1.01-1.15]; P=0.03), female sex (aOR, 1.27 [95% CI, 1.08-1.50]; P=0.004), and smoking (aOR, 1.20 [95% CI, 1.04-1.38]; P=0.01) were independently associated with graft failure, whereas statins were associated with a protective effect (aOR, 0.74 [95% CI, 0.63-0.88]; P<0.001). Graft failure was associated with an increased risk of myocardial infarction or repeat revascularization occurring between CABG and imaging assessment (8.0% in patients with graft failure versus 1.7% in patients without graft failure; aOR, 3.98 [95% CI, 3.54-4.47]; P<0.001). Graft failure was also associated with an increased risk of myocardial infarction or repeat revascularization occurring after imaging (7.8% versus 2.0%; aOR, 2.59 [95% CI, 1.86-3.62]; P<0.001). All-cause death after imaging occurred more frequently in patients with graft failure compared with patients without graft failure (11.0% versus 2.1%; aOR, 2.79 [95% CI, 2.01-3.89]; P<0.001).

CONCLUSIONS

In contemporary practice, graft failure remains common among patients undergoing CABG and is strongly associated with adverse cardiac events.

Angiographic Outcomes for Arterial and Venous Conduits Used in CABG

Coronary artery bypass grafting is the most commonly performed cardiac surgical procedure. Conduit selection is crucial to achieving early optimal outcomes, with graft patency being likely the main driver to long-term survival. We present a review of current evidence on the patency of arterial and venous bypass conduits and of differences in angiographic outcomes.

Acute Coronary Syndromes Among Patients with Prior Coronary Artery Bypass Surgery

PURPOSE OF REVIEW

Acute coronary syndromes (ACS) often occur in individuals with prior coronary artery bypass graft surgery (CABG). Our goal was to describe the prevalence, clinical characteristics, prognosis, and treatment strategies in this group of patients.

RECENT FINDINGS

Studies demonstrate that both acute and long-term major adverse cardiovascular outcomes are increased in patients with ACS and prior CABG compared to those without CABG. Much of this risk is attributed to the greater comorbid conditions present in patients with prior CABG. Data regarding optimal management of ACS in patients with prior CABG are limited, but most observational studies favor an early invasive approach for treatment. Native vessel percutaneous coronary intervention (PCI), if feasible, is generally preferred to bypass graft PCI. Patients with ACS and prior CABG represent a high-risk group of individuals, and implementing optimal preventive and treatment strategies are critically important to reduce the risk.

Association of Dual Antiplatelet Therapy With Ticagrelor With Vein Graft Failure After Coronary Artery Bypass Graft Surgery: A Systematic Review and Meta-analysis

IMPORTANCE

The role of ticagrelor with or without aspirin after coronary artery bypass graft surgery remains unclear.

OBJECTIVE

To compare the risks of vein graft failure and bleeding associated with ticagrelor dual antiplatelet therapy (DAPT) or ticagrelor monotherapy vs aspirin among patients undergoing coronary artery bypass graft surgery.

DATA SOURCES

MEDLINE, Embase, and Cochrane Library databases from inception to June 1, 2022, without language restriction.

STUDY SELECTION

Randomized clinical trials (RCTs) comparing the effects of ticagrelor DAPT or ticagrelor monotherapy vs aspirin on saphenous vein graft failure.

DATA EXTRACTION AND SYNTHESIS

Individual patient data provided by each trial were synthesized into a combined data set for independent analysis. Multilevel logistic regression models were used.

MAIN OUTCOMES AND MEASURES

The primary analysis assessed the incidence of saphenous vein graft failure per graft (primary outcome) in RCTs comparing ticagrelor DAPT with aspirin. Secondary outcomes were saphenous vein graft failure per patient and Bleeding Academic Research Consortium (BARC) type 2, 3, or 5 bleeding events. A supplementary analysis included RCTs comparing ticagrelor monotherapy with aspirin.

RESULTS

A total of 4 RCTs were included in the meta-analysis, involving 1316 patients and 1668 saphenous vein grafts. Of the 871 patients in the primary analysis, 435 received ticagrelor DAPT (median age, 67 years [IQR, 60-72 years]; 65 women [14.9%]; 370 men [85.1%]) and 436 received aspirin (median age, 66 years [IQR, 61-73 years]; 63 women [14.5%]; 373 men [85.5%]). Ticagrelor DAPT was associated with a significantly lower incidence of saphenous vein graft failure (11.2%) per graft than was aspirin (20%; difference, -8.7% [95% CI, -13.5% to -3.9%]; OR, 0.51 [95% CI, 0.35 to 0.74]; P < .001) and was associated with a significantly lower incidence of saphenous vein graft failure per patient (13.2% vs 23.0%, difference, -9.7% [95% CI, -14.9% to -4.4%]; OR, 0.51 [95% CI, 0.35 to 0.74]; P < .001). Ticagrelor DAPT (22.1%) was associated with a significantly higher incidence of BARC type 2, 3, or 5 bleeding events than was aspirin (8.7%; difference, 13.3% [95% CI, 8.6% to 18.0%]; OR, 2.98 [95% CI, 1.99 to 4.47]; P < .001), but not BARC type 3 or 5 bleeding events (1.8% vs 1.8%, difference, 0% [95% CI, -1.8% to 1.8%]; OR, 1.00 [95% CI, 0.37 to 2.69]; P = .99). Compared with aspirin, ticagrelor monotherapy was not significantly associated with saphenous vein graft failure (19.3% vs 21.7%, difference, -2.6% [95% CI, -9.1% to 3.9%]; OR, 0.86 [95% CI, 0.58 to 1.27]; P = .44) or BARC type 2, 3, or 5 bleeding events (8.9% vs 7.3%, difference, 1.7% [95% CI, -2.8% to 6.1%]; OR, 1.25 [95% CI, 0.69 to 2.29]; P = .46).

CONCLUSIONS AND RELEVANCE

Among patients undergoing coronary artery bypass graft surgery, adding ticagrelor to aspirin was associated with a significantly decreased risk of vein graft failure. However, this was accompanied by a significantly increased risk of clinically important bleeding.

2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The guideline for coronary artery revascularization replaces the 2011 coronary artery bypass graft surgery and the 2011 and 2015 percutaneous coronary intervention guidelines, providing a patient-centric approach to guide clinicians in the treatment of patients with significant coronary artery disease undergoing coronary revascularization as well as the supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from May 2019 to September 2019, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, CINHL Complete, and other relevant databases. Additional relevant studies, published through May 2021, were also considered. Structure: Coronary artery disease remains a leading cause of morbidity and mortality globally. Coronary revascularization is an important therapeutic option when managing patients with coronary artery disease. The 2021 coronary artery revascularization guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with coronary artery disease who are being considered for coronary revascularization, with the intent to improve quality of care and align with patients' interests.

2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The guideline for coronary artery revascularization replaces the 2011 coronary artery bypass graft surgery and the 2011 and 2015 percutaneous coronary intervention guidelines, providing a patient-centric approach to guide clinicians in the treatment of patients with significant coronary artery disease undergoing coronary revascularization as well as the supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from May 2019 to September 2019, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, CINHL Complete, and other relevant databases. Additional relevant studies, published through May 2021, were also considered.

STRUCTURE

Coronary artery disease remains a leading cause of morbidity and mortality globally. Coronary revascularization is an important therapeutic option when managing patients with coronary artery disease. The 2021 coronary artery revascularization guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with coronary artery disease who are being considered for coronary revascularization, with the intent to improve quality of care and align with patients' interests.

Secondary Prevention Medications Post Coronary Artery Bypass Grafting Surgery-A Literature Review

Secondary prevention after coronary artery bypass graft (CABG) surgery is imperative in slowing the progression of atherosclerosis in both native and grafted vessels. Aspirin and statins remain the key medications for all patients without significant contraindications. The evidence for dual antiplatelet therapy with clopidogrel is less convincing, but there is hope for newer antiplatelet agents, such as ticagrelor. Meanwhile, β-blockers and angiotensin converting enzyme inhibitors might only offer benefits to specific sub-groups. Post-CABG patients appear to have different medication needs to the general cardiovascular patient and respond differently. In this review, we cover the drug regimens proposed by recent guidelines and the evidence behind their use. Assessing the evidence behind these recommendations, we find that there is an unmet need in some areas for robust population-specific evidence. We hope that future research will address this gap.

Effect of ticagrelor with or without aspirin on vein graft outcome 1 year after on-pump and off-pump coronary artery bypass grafting

Background

In the present post hoc analysis of the DACAB trial, we evaluated the effects of ticagrelor with or without aspirin on 1-year vein graft outcomes after coronary artery bypass grafting (CABG) with and without cardiopulmonary bypass (CPB) (on-pump and off-pump).

Methods

The DACAB trial was a multicenter, randomized, open-label, parallel control study enrolling 500 patients with 1,460 vein grafts undergoing CABG. For current post-hoc study, all patients in the DACAB study were included in the analysis to compare the effects of different antiplatelet regimens under on/off pump. Patients were randomly assigned to 1 of 3 antiplatelet treatment regimens (ticagrelor plus aspirin, T + A; ticagrelor alone, T; or aspirin alone, A) within 24 hours after CABG, and were stratified into on-pump and off-pump subgroups. The primary outcome was 1-year vein graft patency rate.

Results

Totally 121 patients underwent on-pump CABG (39 with 121 vein grafts in T + A, 36 with 101 vein grafts in T, and 46 with 137 vein grafts in A) and 379 patients underwent off-pump CABG (129 with 336 vein grafts in T + A, 130 with 387 vein grafts in T, and 120 with 348 vein grafts in A). Compared with A, T + A showed a higher 1-year vein graft patency rate in both on-pump (adjusted OR for non-patency =0.62, 95% CI: 0.16–2.45) and off-pump (adjusted OR for non-patency =0.35, 95% CI: 0.20–0.62) subgroups, P interaction =0.647; whereas T did not in either on-pump (adjusted OR for non-patency = 0.92, 95% CI: 0.31–2.76) or off-pump (adjusted OR for non-patency =0.58, 95% CI: 0.34–1.00) subgroups, P interaction =0.430.

Conclusions

In the DACAB trial, for patients underwent either on-pump or off-pump CABG, ticagrelor plus aspirin showed consistent benefit for achieving 1-year vein graft patency, with particular benefit being seen in the off-pump.

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

INTRODUCTION

Saphenous vein graft (SVG) is the most common conduit used for coronary artery bypass grafting (CABG) surgery. Unfortunately, SVG are associated with poor long-term patency rates; a significant predictor of re-operation rates and survival. As such, medical therapy to prevent SVG narrowing or occlusion is of paramount importance. Aspirin (ASA) monotherapy is the standard of care after CABG, to improve long-term major adverse cardiovascular events (MACE) and graft patency. Benefits of dual antiplatelet therapy (DAPT) have not been well established in all CABG patients. We present a protocol for a network meta-analysis (NMA) comparing the effects of various antiplatelet therapy regimens on SVG patency, mortality, and bleeding among adult patients following CABG.

METHODS

We will search CENTRAL, MEDLINE, EMBASE, CINAHL ACPJC, and grey literature sources (AHA, ACC, ESC, and CCC conference proceedings, ISRCTN Register, and WHO ICTRP) for randomized controlled trials (RCTs) which fit our criteria. RCTs that evaluate different antiplatelet regimens at least 3-months after CABG and have any of SVG patency, mortality, MACE, and major bleeding as outcomes will be selected. We will perform title and abstract screening, full-text screening, and data extraction independently and in duplicate. Two independent reviewers will also assess risk of bias (ROB) for each study, as well as evaluate quality of evidence using the GRADE framework. We will use R to perform the NMA and use low-dose ASA as reference within our network. We will report results as odds ratios with confidence intervals for direct comparisons, and credible intervals for indirect or mixed comparisons. We will use the surface under the cumulative ranking curve (SUCRA) to estimate the ranking of interventions.

DISCUSSION

Given the limited direct comparison of various antiplatelet regimens, a network approach is ideal to clarify the optimum antiplatelet therapy after CABG. We hope that our NMA will be the largest quantitative synthesis evaluating antiplatelet regimens among patients requiring CABG. It should inform clinicians and guideline developers in selecting the most effective and safest antiplatelet regimen.Systematic Review registration: International Prospective Register for Systematic Reviews (PROSPERO)-CRD42019127695.