Pattern and predictors of dual antiplatelet use after coronary artery bypass graft surgery

Optimal antiplatelet strategy following coronary artery bypass grafting: a meta-analysis

OBJECTIVE

Coronary artery bypass grafting (CABG) is an established revascularisation strategy for multivessel and left main coronary artery disease. Although aspirin is routinely recommended for patients with CABG, the optimal antiplatelet regimen after CABG remains unclear. We evaluated the efficacies and risks of different antiplatelet regimens (dual (DAPT) versus single (SAPT), and dual with clopidogrel (DAPT-C) versus dual with ticagrelor or prasugrel (DAPT-T/P)) after CABG.

METHODS

We followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and performed a comprehensive literature search using PubMed, Ovid Medline, Ovid Embase and Cochrane Central Register of Controlled Trials. Data were extracted and pooled using random-effects models and Review Manager (V.5.4).

RESULTS

Among the 2970 article abstracts screened, 215 full-text articles were reviewed and 38 studies totaling 77 447 CABG patients were included for analyses. DAPT compared with SAPT was associated with significantly lower all-cause mortality (OR 0.65 with 95% CI 0.50 to 0.86; p=0.002), cardiovascular mortality (OR 0.53, 95% CI 0.33 to 0.84; p=0.008), and major adverse cardiac and cerebrovascular events (MACCE) (OR 0.68, 95% CI 0.51 to 0.91; p=0.01), but higher rates of major (OR 1.30, 95% CI 1.08 to 1.56; p=0.007) and minor bleeding (OR 1.87, 95% CI 1.28 to 2.74; p=0.001) after CABG. DAPT-T/P compared with DAPT-C was associated with significantly lower all-cause (OR 0.43, 95% CI 0.29 to 0.65; p≤0.0001) and cardiovascular mortality (OR 0.44, 95% CI 0.24 to 0.80; p=0.008), and no differences on other cardiovascular or bleeding outcomes after CABG.

CONCLUSION

In patients with CABG, DAPT compared with SAPT and DAPT-T/P compared with DAPT-C were associated with reduction in all-cause and cardiovascular mortality, especially in patients with acute coronary syndrome. Additionally, DAPT was associated with reduction in MACCE, but higher rates of major and minor bleeding. An individualised approach to choosing antiplatelet regimen is necessary for patients with CABG based on ischaemic and bleeding risks.

Dual-Antiplatelet Therapy After Coronary Artery Bypass Grafting: A Survey of UK Cardiac Surgeons

OBJECTIVE

Antiplatelet therapy after coronary artery bypass grafting (CABG) is important in postoperative medical management. Although cardiac surgeons are well-versed in the guidelines regarding discontinuation of dual-antiplatelet therapy (DAPT; aspirin and a P2Y12 antagonist) before CABG to minimize bleeding risk, there is considerable variability in DAPT dosing after CABG. The objective of this study was to explore the current trends in DAPT after CABG in the UK to improve understanding of the existing practice.

DESIGN

This study used an online survey with 9 questions about the use of DAPT after CABG. An invitation to participate was sent to all adult cardiac surgeons currently in practice in the UK and the Republic of Ireland.

SETTING

The study was conducted in the UK and the Republic of Ireland.

PARTICIPANTS

Participants in this study were adult cardiac surgeons currently in practice in the UK and the Republic of Ireland.

INTERVENTIONS

There were no interventions in this study.

MEASUREMENTS AND MAIN RESULTS

Responses were received from across the UK (85.4% UK; 4% each from Scotland and Northern Ireland, 1.3% from Wales) and 5.3% from the Republic of Ireland. Fifty-seven percent of the respondents performed between 50 and 100 CABGs per year. Ninety-one percent of the respondents prescribe DAPT postoperatively, but the choice of which patients receive it varied. Most responding surgeons used DAPT for selective patient cohorts, such as those with acute coronary syndrome (51%), diffuse coronary artery disease (42%), perioperative myocardial infarction (36%), coronary endarterectomy (31%), or when bypassing a stented coronary artery (23%). Thirty-eight percent of the respondents began all their patients with CABGs on DAPT. The most preferred P2Y12 antagonist was clopidogrel, used by 75% of respondents and introduced on day 1 after surgical revascularization (71%). The routine duration for DAPT is 12 months, which 78% of the respondents preferred. The main reason for not starting DAPT in those surveyed was the bleeding risk associated with DAPT (72%).

CONCLUSIONS

The survey uncovered variation in the use of DAPT after CABG. However, DAPT remains the preferred strategy after CABG in the UK. The study highlighted the need to develop standardized protocols for DAPT after CABG.

Center Variation in Use of Preoperative Dual Antiplatelet Therapy and Platelet Function Testing at the Time of Coronary Artery Bypass Grafting in Maryland

BACKGROUND

Patients presenting with acute coronary syndrome are administered a P2Y12 inhibitor and aspirin before coronary catheterization to prevent further myocardial injury from thrombosis. Guidelines recommend a standard waiting period between the time patients are administered dual antiplatelet therapy (DAPT) and elective cardiac surgery. Since 25% to 30% of the population may be considered nonresponders to clopidogrel, platelet function testing can be utilized for timing of surgery and to assess bleeding risks. The extent to which a standard waiting period or platelet function testing is used across centers is not established, representing an important opportunity to standardize practice.

METHODS

We conducted a retrospective cohort study from 2011 to 2020 using data from the Maryland Cardiac Surgical Quality Initiative, a consortium of all 10 hospitals in the state performing cardiac surgery. The proportion of patients administered DAPT within 5 days of surgery was examined by hospital over the time period. Mixed-effects multivariable logistic regressions were used to examine the association of preoperative DAPT with ischemic and bleeding outcomes. Centers were surveyed on use or nonuse of preoperative platelet function testing, and bleeding outcomes were compared.

RESULTS

There was significant heterogeneity of preoperative DAPT usage across centers ranging from 2% to 54% (P < .001). DAPT within 5 days of isolated coronary artery bypass grafting (CABG) was associated with higher odds of reoperation for bleeding (odds ratio [OR], 1.55; 95% confidence interval [CI], 1.19-2.01; P = .001), >2 units of red blood cells (RBCs) transfused (OR, 1.62; 95% CI, 1.44-1.81; P < .001), and >2 units of non-RBCs transfused (OR, 1.79; 95% CI, 1.60-2.00; P < .001). In the 5 hospitals using preoperative platelet function testing to guide timing of surgery, there were greater odds for DAPT within 5 days (OR, 1.33; 95% CI, 1.22-1.45; P < .001), fewer RBCs >2 units transfusions (22% vs 33%; P < .001), and non-RBCs >2 units (17% vs 28%; P < .001) transfusions within DAPT patients.

CONCLUSIONS

There is significant variability in DAPT usage within 5 days of CABG between hospital centers. Preoperative platelet function testing may allow for earlier timing of surgery for those on DAPT without increased bleeding risks.

Determinants of long-term dual antiplatelet therapy use in post myocardial infarction patients: Insights from the TIGRIS registry

BACKGROUND

Patterns of dual antiplatelet therapy (DAPT) use beyond 1 year post-myocardial infarction (MI) have not been well studied.

METHODS

TIGRIS (NCT01866904) was a prospective, multi-center (369 centers in 24 countries), observational study of patients 1 to 3 years post-MI. We sought to identify the prevalence and determinants of DAPT use ≥1 year post-MI in patients enrolled in TIGRIS. We used multivariable logistic regression to identify determinants of DAPT use at 396 days post-MI (365 days plus a 31day overrun period to account for intended DAPT discontinuation at 1 year). Patients treated with an oral anticoagulant were excluded.

RESULTS

Of 7708 patients (median age 67 years, women 25%, ST-elevation MI 50%), 39% and 16% were on DAPT at 396 days and 5 years post-MI, respectively. DAPT use at 396 days post-MI was more prevalent in patients <65 years of age, treated with percutaneous coronary intervention (versus coronary artery bypass grafting or medical therapy), and with multivessel disease or a history of angina. Additional clinical determinants of ischemic and/or bleeding events following MI (diabetes, second prior MI, hypertension, peripheral artery disease, heart failure, smoking, and renal insufficiency) were not independently associated with DAPT use at 396 days. There were geographic variations in the use of DAPT at 396 days (p<0.001), with the lowest use in Europe and the highest in Asia and Australia.

CONCLUSION

In a contemporary patient cohort, DAPT use beyond 1 year post MI was prevalent and associated with patient and index event characteristics. There were marked geographical variations in DAPT use beyond 1 year post MI.

Dual antiplatelet therapy is under-prescribed in patients with surgically treated acute myocardial infarction

OBJECTIVES

Despite guideline recommendations, previous reports, coming mainly from outside Europe, showed low rates of prescriptions for dual antiplatelet therapy (DAPT) in patients with acute myocardial infarction (AMI) undergoing surgical revascularization. The present study assesses this issue in the era of potent P2Y12 inhibitors in Switzerland.

METHODS

All patients with a diagnosis of AMI included in the Acute Myocardial Infarction in Switzerland Plus Registry from January 2014 to December 2019 were screened; 9050 patients undergoing either percutaneous (8727, 96.5%) or surgical (323, 3.5%) revascularization were included in the analysis.

RESULTS

Surgically treated patients were significantly less likely to receive DAPT at discharge (56.3% vs 96.7%; P < 0.001). Even when discharged with a prescription for DAPT, those patients were significantly less likely to receive a regimen containing a new P2Y12 inhibitor (67/182 [36.8%] vs 6945/8440 [83.2%]; P < 0.001). At multivariate analysis, surgical revascularization was independently associated with a lower likelihood of receiving a prescription for DAPT at discharge (odds ratio 0.03, 95% confidence interval 0.02-0.06).

CONCLUSIONS

DAPT prescriptions for patients with AMI undergoing surgical revascularization are not in line with current guideline recommendations. Efforts are necessary to clarify the role of DAPT for secondary prevention in these patients and increase the confidence of treating physicians in guideline recommendations.

CLINICAL TRIAL REGISTRATION

Acute Myocardial Infarction in Switzerland Plus Registry; registration number at ClinicalTrials.gov: NCT01305785.

Initiation of and persistence with P2Y12 inhibitors in patients with myocardial infarction according to revascularization strategy: a nationwide study

BACKGROUND

We aimed to analyse initiation of and persistence with P2Y12 inhibitors after first-time myocardial infarction (MI).

METHODS AND RESULTS

Using Danish nationwide registries, we identified patients ≥30 years with first-time MI during 1 January 2005-30 June 2016 and subsequent prescriptions of P2Y12 inhibitors. Independent factors related to initiation of and persistence with P2Y12 inhibitors were analysed by multivariable logistic regression and a Cox proportional hazards model. Patients were stratified by revascularization strategy: percutaneous coronary intervention (PCI), coronary artery bypass graft (CABG), or medical therapy alone (MTA). Overall, 79 597 MI patients were included with 39 172 undergoing PCI, 2619 CABG, and 16 640 MTA, showing initiation of P2Y12 inhibitors of 93.4%, 49.0%, and 51.5%, respectively. Congestive heart failure, cerebrovascular disease, cardiac dysrhythmias, renal failure, previous bleeding, and oral anticoagulants were associated with less initiation of P2Y12 inhibitors. Female sex was associated with less initiation of P2Y12 inhibitors following MTA. MTA, coronary angiography, cerebrovascular disease, diabetes with complications, previous bleeding, antidiabetics, and ticagrelor as P2Y12 inhibitor were associated with non-persistence, whereas female sex, advanced age, and concomitant pharmacotherapy with angiotensin-converting enzyme inhibitors, beta-blockers, statins, oral anticoagulants, and aspirin were associated with high persistence.

CONCLUSION

Initiation of P2Y12 inhibitors in PCI-treated MI patients was high in contrast to those treated with CABG or MTA and patients with certain comorbidities. Further studies on the benefit-risk ratio of P2Y12 inhibitors in CABG-treated or MTA-treated patients and patients with comorbidities after first-time MI are warranted, as is focus on persistence among patients receiving MTA, patients with comorbidities, and users of ticagrelor.

Non-Vitamin K Antagonist Oral Anticoagulant vs Warfarin for Post Cardiac Surgery Atrial Fibrillation

BACKGROUND

Treatment guidelines for nonvalvular atrial fibrillation (AF) recommend use of non-vitamin K antagonist oral anticoagulants (NOACs) over warfarin, yet clinical trials excluded individuals with post cardiac surgery AF. We sought to compare outcomes with NOACs vs warfarin for new onset post cardiac surgery AF.

METHODS

We examined 26,522 patients from The Society of Thoracic Surgeons' database with post cardiac surgery AF who were discharged on oral anticoagulation from July 2017-December 2018. Three primary outcomes were evaluated: 30-day mortality, major bleeding complications, and stroke/transient ischemic attack. Secondary outcomes included postoperative length of stay, 30-day myocardial infarction, venous thromboembolism, and pericardial effusion/tamponade.

RESULTS

A total of 9769 (36.8%) participants were prescribed NOACs and 16,753 (63.2%) warfarin. In multivariable analysis, there was no association between type of anticoagulant and 30-day major bleeding complications (odds ratio [OR]_{NOAC/warfarin} 0.76, 95% confidence interval [CI] 0.49-1.18), stroke/transient ischemic attack (OR_{NOAC/warfarin} 0.94, 95% CI 0.53-1.67) or mortality (OR_{NOAC/warfarin} 1.08, 95% CI 0.80-1.45). After stratification by renal function or isolated coronary bypass vs valve surgery, there remained no difference in the primary outcomes. Additionally, there was no difference in 30-day myocardial infarction (OR_{NOAC/warfarin} 1.17, 95% CI 0.62-2.22), venous thromboembolism (OR_{NOAC/warfarin} 0.91, 95% CI 0.47-1.78), or pericardial effusion/tamponade (OR_{NOAC/warfarin} 1.09, 95% CI 0.80-1.47) between the 2 groups. NOAC therapy was associated with a half-day reduction in postoperative length of stay (β_{NOAC/warfarin} -0.47, 95% CI -0.62 to -0.33).

CONCLUSIONS

NOACs are associated with a reduction in postoperative length of stay, without excess bleeding or other short-term complications, compared with warfarin. These findings support the broader use of NOACs as a safe alternative to warfarin in patients with post cardiac surgery AF at elevated stroke risk and acceptable bleeding risk.

Hospital Variability Drives Inconsistency in Antiplatelet Use After Coronary Bypass

BACKGROUND

Continuation of dual antiplatelet therapy (DAPT) after coronary artery bypass grafting (CABG) after acute myocardial infarction is recommended by current guidelines. We sought to evaluate guideline adherence over time and factors associated with postoperative DAPT within a regional consortium.

METHODS

Isolated CABG patients from 2011 to 2017 who had a myocardial infarction within 21 days prior to surgery were included. Patients were stratified by DAPT prescription at discharge and by time period, early (2011-2014) vs late (2015-2017). Hierarchical regressions were then performed to evaluate factors influencing DAPT use after CABG.

RESULTS

A total of 7314 patients were included with an overall rate of DAPT utilization of 31.2% that increased from 29.6% in the early to 33.4% in the late era (P < .01). There was considerable variability in hospital rates of DAPT (range 9.5%-92.1%) and hospital level changes over time (26% increased, 11% decreased, and 63% remained stable). After adjustment for clinical factors, era was not associated with DAPT use but treating hospital remained significantly associated with DAPT use. Other clinical factors associated with increased DAPT utilization included off-pump surgery (odds ratio [OR] 4.48, P < .01) and prior percutaneous coronary intervention (OR 2.02, P < .01), and atrial fibrillation (OR 0.39, P < .01) was associated with decreased utilization.

CONCLUSIONS

Dual antiplatelet use has increased between 2011 and 2017, driven primarily by evolving patient demographics. Significant hospital-level variability drives inconsistency in DAPT utilization. Efforts to promote DAPT use for patients treated with CABG after myocardial infarction in concordance with current guidelines should be targeted at the hospital level.

Dual antiplatelet therapy versus aspirin monotherapy in diabetics with stable ischemic heart disease undergoing coronary artery bypass grafting

Background

Dual antiplatelet therapy (DAPT) in patients presenting with acute coronary syndrome (ACS) undergoing CABG is recommended to prevent recurrent ischemic events. The benefit of DAPT post-CABG in patients with stable ischemic heart disease (SIHD) is unknown. The aim of this study was to evaluate the utilization rate of DAPT and associated outcomes in patients with SIHD undergoing CABG via a secondary analysis of Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial data.

Methods

In a post-hoc, nonrandomized analysis from the BARI 2D trial, we compared patients receiving DAPT and aspirin monotherapy within 90 days post-randomization. The primary outcome was the risk adjusted 5-year composite of all-cause mortality, nonfatal myocardial infarction (MI), or stroke. We analyzed patients assigned to prompt CABG treatment arm including both the insulin therapy assignments.

Results

Of 378 patients, within 90 days post-randomization, 59 (16%) patients received DAPT and 319 (84%) patients received aspirin alone. Cox proportional hazard analysis demonstrated that there was no significant difference in the 5-year composite event of death, MI, and stroke between DAPT and monotherapy cohorts [13 (22.0%) vs. 61 (19.1%); adjusted hazard ratio (HR): 1.06; 95% confidence interval (CI): 0.56 to 2.00; P=0.86]. There also was no significant difference at 1 year in the composite event [6 (10.2%) vs. 30 (9.4%); HR: 1.13; 95% CI: 0.46 to 2.79; P=0.79].

Conclusions

The use of DAPT in patients with diabetes post-CABG in this cohort was low. Compared with aspirin monotherapy, no associated differences were observed in cardiovascular outcomes. Larger prospective studies are needed to further elucidate this observation.