Hemostatic effects of tranexamic acid in cardiac surgical patients with antiplatelet therapy: a systematic review and meta-analysis

BACKGROUND

The purpose of the current study was to assess the efficacy of tranexamic acid (TXA) on reducing bleeding in cardiac surgical patients with preoperative antiplatelet therapy (APT).

METHODS

Five electronic databases were searched systematically for randomized-controlled trials (RCTs) assessing the impact of intravenous TXA on post-operative bleeding on cardiac surgical patients with preoperative APT until May 2024. Primary outcome of interest was post-operative blood loss. Secondary outcomes of interest included the incidence of reoperation due to post-operative bleeding, post-operative transfusion requirements of red blood cells (RBC), fresh-frozen plasma (FFP), and platelet concentrates. Mean difference (MD) with 95% confidence interval (CI) or odds ratios (OR) with 95% CI was employed to analyze the data. Subgroup and meta-regression analyses were performed to assess the possible influence of TXA administration on reducing bleeding and transfusion requirements.

RESULTS

A total of 12 RCTs with 3018 adult cardiac surgical patients (TXA group, 1510 patients; Control group, 1508 patients) were included. The current study demonstrated that TXA significantly reduced post-operative blood loss (MD =  - 0.38 L, 95% CI: - 0.73 to - 0.03, P = 0.03; MD =  - 0.26 L, 95% CI: - 0.28 to - 0.24, P < 0.00001; MD =  - 0.37 L, 95% CI: - 0.63 to - 0.10, P = 0.007) in patients receiving dual antiplatelet therapy (DAPT), aspirin, or clopidogrel, respectively. Patients in TXA group had significantly lower incidence of reoperation for bleeding as compared to those in Control group. The post-operative transfusion of RBC and FFP requirements was significantly lower in TXA group than Control group. Subgroup analyses showed that studies with DAPT discontinued on the day of surgery significantly increased the risk of post-operative blood loss [(MD: - 1.23 L; 95% CI: - 1.42 to - 1.04) vs. (MD: - 0.16 L; 95% CI: - 0.27 to - 0.05); P < 0.00001 for subgroup difference] and RBC transfusion [(MD: - 3.90 units; 95% CI: - 4.75 to - 3.05) vs. (MD: - 1.03 units; 95% CI: - 1.96 to - 0.10); P < 0.00001 for subgroup difference] than those with DAPT discontinued less than 5-7 days preoperatively.

CONCLUSIONS

This meta-analysis demonstrated that TXA significantly reduced post-operative blood loss and transfusion requirements for cardiac surgical patients with preoperative APT. These potential clinical benefits may be greater in patients with aspirin and clopidogrel continued closer to the day of surgery.

TRIAL REGISTRATION NUMBER

CRD42022309427.

Impact of Ticagrelor Versus Clopidogrel on Bleeding Outcomes of Isolated Coronary Artery Bypass Grafting

BACKGROUND

Increased bleeding risks have been documented in patients exposed to P2Y₁₂ inhibitors within 5 days of coronary artery bypass surgery (CABG). This study aimed to determine the relative CABG bleeding risks of clopidogrel versus ticagrelor exposure and the proper time course of ticagrelor discontinuation prior to surgery.

METHODS

Clinical outcomes were assessed in 2075 isolated CABG patients, including 375 who had received P2Y₁₂ inhibitors within 5 days of surgery (155 clopidogrel, 213 ticagrelor, 7 prasugrel). BARC-4 CABG bleeding complications and perioperative blood product usage were assessed in propensity-matched P2Y₁₂-inhibited and non-P2Y₁₂-inhibited cohorts.

RESULTS

P2Y₁₂-inhibited patients (n = 375) in comparison to matched non-P2Y₁₂-inhibited patients (n = 1138) had higher rates of re-operation for bleeding (3.8 % vs 1.3 %, p = 0.003), postoperative red blood cell transfusion ≥5 units (5.7 % vs 2.7 %, p = 0.007), and intraoperative and postoperative blood product utilization (42.3 % vs 27.1 %, p < 0.001; 41.8 % vs 32.2 %, p < 0.001, respectively). Univariate predictors of BARC-4 bleeding included clopidogrel (OR: 2.145, 95 % CI: 1.131-4.067, p = 0.019) and ticagrelor discontinued within 3 days of surgery (OR: 2.153, 95 % CI: 1.003-4.169, p = 0.049). Multivariate logistic regression demonstrated that only clopidogrel exposure was an independent BARC-4 bleeding predictor (OR: 1.850, 95 % CI: 1.007-3.398, p = 0.048). Unadjusted ticagrelor patients with drug discontinuation 4-5 days prior to CABG only demonstrated higher rates of perioperative platelet transfusion, without additional signs of excessive bleeding.

CONCLUSIONS

Clopidogrel exposure within 5 days of CABG is an independent predictor of BARC-4 bleeding, whereas major ticagrelor bleeding effects are confined to drug exposure within 3 days of surgery.

Platelet Reactivity and Outcomes after Off-Pump Coronary Surgery in Acute Coronary Syndrome Patients

Ischemic and hemorrhagic complications are major determinants of survival in acute coronary syndrome (ACS) patients undergoing coronary surgery. We investigated the association of preoperative platelet reactivity to P2Y₁₂ antagonists with ischemic and hemorrhagic complications after Off-Pump Coronary Artery Bypass surgery (OPCAB) in ACS patients who received dual anti-platelet therapy (DAPT) within 5 days prior to surgery. This prospective, observational study with 177 patients compared the incidence of perioperative major bleeding and major adverse cardiac events (MACEs) in relation to the tertile distribution of the % inhibitory response to P2Y₁₂ antagonists, as measured by a thromboelastography platelet mapping assay. The incidences of perioperative major bleeding and MACEs were similar in relation to the tertile distribution of inhibitory response to P2Y₁₂ antagonists. The % inhibitory responses to P2Y₁₂ antagonists between patients who did or did not exhibit MACEs, and with or without major bleeding, were 58 ± 20% and 56 ± 20% (p = 0.578) and 57 ± 19% and 56 ± 21% (p = 0.923), respectively. In ACS patients who received DAPT close to OPCAB, the platelet inhibitory response to P2Y₁₂ antagonists was not associated with ischemic or hemorrhagic complications. OPCAB may obviate the need for routine platelet function testing for ACS patients requiring DAPT and surgical revascularization. Clinical Registration Number: NCT02184884.

Dual antiplatelet therapy before coronary artery bypass grafting in patients with myocardial infarction: a prospective cohort study

BACKGROUND

Dual antiplatelet therapy (DAPT) in patients with MI who are candidates for early coronary artery bypass grafting (CABG) can affect intraoperative and postoperative outcomes. Therefore, the aim of this study was to evaluate the effect of DAPT up to the day before CABG on the outcomes during and after surgery in patients with MI.

METHODS

In this prospective cohort study, 224 CABG candidate patients with and without MI were divided into two groups: (A) patients without MI who were treated with aspirin 80 mg/day before surgery (noMI-aspirin group; n = 124) and (B) patients with MI who were treated with aspirin 80 mg/day before surgery and clopidogrel (Plavix brand) at a dose of 75 mg/day (MI-DAPT group; n = 120). Dual or mono-antiplatelet therapy continued until the day before surgery. Patients were followed to assess in-hospital and 6-months outcomes.

RESULTS

The in-hospital mortality in MI-DAPT group was similar with noMI-aspirin group (OR 4.2; 95% CI 0.9-20.5; p = 0.071). The prevalence of CVA (p = 0.098), duration of hospital stay (p = 0.109), postoperative ejection fraction level (p = 0.693), diastolic dysfunction grade (p = 0.651) and postoperative PAP level (p = 0.0364) did not show difference between two groups. No mild or severe bleeding was observed in the patients. Six-month follow up showed that number of readmissions (p = 0.801), number of cases requiring angiography (p = 0.100), cases requiring re-PCI (p = 0.156), need for re-CABG (p > 0.999) and CVA (p > 0.999) did not differ between the two groups. During the 6-month follow-up, out-hospital mortality did not differ significantly between the two groups (p = 0.446).

CONCLUSIONS

A 6-month follow-up showed that DAPT with aspirin and clopidogrel before CABG in patients with MI has no effect on postoperative outcomes more than mono-APT with aspirin. Therefore, DAPT is recommended in the preoperative period for these patients.

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.

Early Chest Re-Exploration for Excessive Bleeding in Post Cardiac Surgery Patients: Does It Matter?

Introduction

Re-explorations after open-heart surgery are often required if the patient is bleeding or shows features of cardiovascular instability and does not improve with conservative measures. Our study aims to determine whether timely re-exploration of patients who are bleeding has an impact on the morbidity and mortality of the patients.

Methods

A retrospective analysis of 75 patients that underwent open-heart surgery and subsequently underwent chest re-exploration for excessive bleeding between March 2018 and March 2020. Patients who were reopened post-op for indications other than excessive bleeding were excluded.

Results

A total number of cases were 700, out of which 75 (9.3%) patients were reopened, as compared to the literature, which shows worldwide 2-11% being reopened. Post-operative drain output was 1000ml to 1500ml in 47 (62.7%) and more than 1500ml in 28 (37.3%) patients before they were reopened. In 67 (89.3%) patients, three to five units of blood were transfused, and in eight (10.7%) patients, more than five units of blood were transfused. We believe our mortality in the reopened patients was low, because of timely intervention and early re-exploration, and is probably the reason why our figures land in a higher range (2-11%) of reopened cases (9.3%). Reopening time was less than five hours in 49 (65.3%) patients and less than 10 hours in 26 (34.7%) patients in our study. We tried to minimize the loss of blood and re-explored the patients before they lose excessive blood, the average time for reopening in our study was less than 10 hours. The average intensive care unit (ICU) stay was 4.2 days (range three to six days). Wound infections were reported in one of three patients. There was no mortality in these patients. Surgical site of bleeding was identified in 54 (72%) patients and no particular site was found in 21 (28%) patients. Suggesting that it is common to have a surgical bleeder than coagulopathy induced bleeding in post-cardiac surgery patients

Conclusions

We believe our low mortality (0%) is due to early reopening in patients who are bleeding excessively after cardiac surgery.

MiR-223 levels predicting perioperative bleeding in off-pump coronary artery bypass grafting

Background

To investigate the predictive value of platelet-related microRNAs (miRNAs) for bleeding during and after off-pump coronary artery bypass grafting (OPCABG) and the influence of dual antiplatelet therapy (DAPT) on miRNAs.

Methods

This prospective study included 59 patients scheduled for OPCABG. The plasma miR-126 and miR-223 levels were measured and platelet aggregation was determined by thromboelastography during DAPT. The plasma miRNA levels were compared between patients treated with ticagrelor or clopidogrel. Multivariable logistic regression analysis was performed to determine the independent risk factors for bleeding during and after surgery. Active bleeding was defined as a blood loss >1.5 mL/kg/h for 6 consecutive hours within the first 24 hours or in case of reoperation during the first 12 postoperative hours. Severe perioperative bleeding was defined using the universal definition of perioperative bleeding in adult cardiac surgery.

Results

Higher circulating miR-223 levels [odds ratio (OR) =1.348, 95% confidence interval (CI): 1.001–1.814, P=0.047] and lower body mass index (OR =0.648, 95% CI: 0.428–0.980, P=0.040) were independent predictors for severe perioperative bleeding in OPCABG. Ticagrelor treatment led to significant increases in circulating miR-223 levels compared with clopidogrel treatment.

Conclusions

The plasma miR-223 levels served as a predictor for bleeding during and after OPCABG. Circulating miR-223 levels were significantly elevated with ticagrelor treatment compared with clopidogrel treatment. MiR-223 may be a novel biomarker for bleeding in cardiac surgery and can help explain the different efficacies of ticagrelor and clopidogrel.

Association of Adenosine Diphosphate-Induced Platelet Maximum Amplitude With Postoperative Bleeding and Blood Transfusions in Patients Undergoing Coronary Artery Bypass Grafting

OBJECTIVES

To investigate the association of adenosine diphosphate (ADP)-induced platelet maximum amplitude (MA_ADP) with postoperative bleeding and blood product transfusions in patients undergoing coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB).

DESIGN

This single-center observational study recruited 200 patients who underwent elective, first-time, isolated CABG with CPB. A rapid thromboelastography with platelet mapping test was conducted for all patients before the surgery. Patients were categorized by the preoperative MA_ADP into ≤50 mm (MA_ADP ≤50 group [n = 87]) and MA_ADP >50 mm (MA_ADP >50 group [n = 113]). The primary outcome was postoperative bleeding at 6 and 24 hours as measured by chest tube drainage volume. The perioperative blood product transfusions, postoperative complications, postoperative time course, and in-hospital mortality also were evaluated.

SETTING

University hospital.

PARTICIPANTS

Adult patients scheduled to undergo isolated primary CABG with CPB.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The study included 200 patients who underwent CABG with CPB. MA_ADP was >50 mm in 113 (56.5%) patients (MA_ADP >50 group). Compared with the MA_ADP >50 group, the postoperative chest tube drainage volume at 6 and 24 hours was significantly greater in the patients with MA_ADP ≤50 mm (476.90 ± 156.36 mL v 403.36 ± 133.24 mL; p < 0.001 and 935.86 ± 318.43 mL v 667.21 ± 222.75 mL; p < 0.001, respectively). The consumption of blood products in patients with MA_ADP ≤50 mm was significantly more than those with MA_ADP >50 mm. The durations of intensive care unit stay and length of postoperative hospital stay were markedly longer in the MA_ADP ≤50 group than in the MA_ADP >50 group (p = 0.001 and p = 0.005; respectively). There were no significant differences in adverse outcomes between the 2 groups except for the postoperative atrial fibrillation, which occurred more in the MA_ADP ≤50 group than in the MA_ADP >50 group (8.05% v 1.77%; p = 0.043). MA_ADP (area under the receiver operating characteristic curve of 0.767; p < 0.001) was demonstrated to have significant ability to predict bleeding tendency, with a sensitivity of 76.2% and a specificity of 69.0%.

CONCLUSIONS

Preoperative MA_ADP may play a potential role in the prediction of postoperative bleeding and allogeneic blood transfusions and guide clinicians in perioperative management of patients undergoing CABG with CPB.

Reoperation for bleeding following coronary artery bypass surgery with special focus on long-term outcomes

Objectives: We studied the incidence and risk factors of reoperation for bleeding following CABG in a nationwide cohort with focus on long-term complications and survival. Design: A retrospective study on 2060 consecutive, isolated CABG patients operated 2001-2016. Outcome of reoperated patients (n = 130) were compared to non-reoperated ones (n = 1930), including major adverse cardiac and cerebrovascular events (MACCE) and overall survival. Risk factors for reoperation were determined using multivariate logistic regression and a Cox proportional hazards model to assess prognostic factors of long-term survival. Median follow-up was 7.6 years. Results: One hundred thirty patients (6.3%) were reoperated with an annual decrease of 4.1% per year over the study period (p=.04). Major complications (18.5 vs. 9.6%) and 30-day mortality (8.5 vs. 1.9%,) were higher in the reoperation group (p<.001). The use of clopidogrel preoperatively (OR 3.62, 95% CI: 1.90-6.57) and reduced left ventricular ejection fraction (OR 2.23, 95% CI: 1.25-3.77) were the strongest predictors of reoperation, whereas off-pump surgery was associated with a lower reoperation risk (OR 0.44, 95% CI: 0.22-0.85). After exluding patients that died within 30 days postoperatively, no difference in long-term survival or freedom from MACCE was found between groups, and reoperation was not an independent risk factor for long-term mortality in multivariate analysis. Conclusions: The reoperation rate in this study was relatively high but decreased significantly over time. Reoperation was associated with twofold increased risk for major complications and fourfold 30-day mortality, but comparable long-term MACCE and survival rates. This implies that if patients survive the first 30 days following reoperation, their long-term outcome is comparable to non-reoperated patients.

Dual antiplatelet therapy up to the time of non-elective coronary artery bypass grafting with prophylactic platelet transfusion: is it safe?

Background

Guidelines suggest that patients discontinue Clopidogrel at least 5 days prior to coronary artery bypass grafting (CABG). Those with acute coronary syndrome (ACS) are at high risk for myocardial infarction (MI) if not treated with dual antiplatelet therapy (DAPT). We sought to assess pre and post-operative outcomes of patients maintained on Clopidogrel and aspirin up to the time of surgery and compare them with those on aspirin alone.

Methods

From the cardiac surgery database, 240 patients were retrospectively registered between January and May 2017. There were 126 patients with ACS who underwent CABG on DAPT (Clopidogrel group [CG]) and 114 patients who underwent elective CABG on aspirin alone (control). The CG received intraoperative prophylactic platelet transfusion (PPT). Demographics, comorbidities, and laboratory data were prospectively entered at the time of surgery and were subsequently retrieved for analysis. Per and postoperative findings were identified and compared between both groups.

Results

The cohort consisted of 240 patients (mean age 61 years, 81.3% were male, SD ± 9.58). Patients in the CG were younger (Median 57 vs. 63, P-value 0.001), and with male predominance (86% versus 75%, P-value 0.028). In addition, they had less prevalence for diabetes and renal failure as compared to control (P-values 0.003, and 0.005, respectively). There were no significant differences between both groups in number of vessels grafts, duration of on-pump and aortic clamp. Hematologic laboratory data had also similar baseline values. The CG had similar bleeding rate, redo surgery and in-hospital death (P-values non-significant), however more infection and total hospital stay as compared to control (p-values 0.048 and 0.001).

Conclusion

Patients who are at increased risk for MI can be maintained on DAPT up to the time of CABG because surgery is safe when patients are offered PPT.

To jump or not to jump? A multicentre propensity-matched study of sequential vein grafting of the heart†

OBJECTIVES

In this propensity-matched study we investigated the outcome after grafting with either a single vein or a sequential vein grafting strategy. Outcomes were primarily risk of reintervention and death in the short, intermediate and long term (10 years).

MATERIALS

In the period from 2000 to 2016, data from 24 742 patients undergoing coronary artery bypass grafting were extracted from the Western Denmark Heart Registry, where data are registered perioperatively. We used a propensity-matched study in which the study groups were matched on parameters primarily from the EuroSCORE. The numbers of patients in both groups after matching were 3380.

RESULTS

Single grafts resulted in significantly more postoperative bleeding and were more time-consuming. No differences were seen regarding in-hospital events such as stroke, acute myocardial infarction, dialysis or arrhythmias. After 30 days, patients in the jump graft group showed an increased rate of reintervention due to ischaemia after adjusting for confounding factors [hazard ratio (HR) 2.08, 95% confidence interval 1.01-4.34]. In addition, after adjusting for known confounders, sequential grafts were found to increase the risk of mortality at 6 months (HR 1.51, 95% confidence limits 1.07-2.11) and 5 years (HR 1.23, 95% confidence limits 1.04-1.46).

CONCLUSIONS

This propensity-matched analysis suggested, although discretely, that a jump graft as a grafting strategy is associated with a slightly increased risk of mortality and early graft failure and that a single grafting strategy to the coronary arteries should be preferred when feasible.

Is Preoperative Clopidogrel Resistance a Predictor of Bleeding and Risks in Patients Undergoing Emergency CABG Surgery?

Objective

The aims of this study were to determine whether the detection of preoperative clopidogrel resistance in patients undergoing cardiac surgery while using clopidogrel could play a guiding role in the prediction of postoperative excessive bleeding, transfusion requirements, and risks and to provide clinically significant data.

Methods

Two hundred and twenty-two patients [median age: 59.4 (38-83) years; 38 females] undergoing emergency and elective coronary artery bypass graft (CABG) surgeries in our clinic were evaluated prospectively. Patients with multiple systemic diseases, other than diabetes mellitus (DM) and hypertension (HT), were excluded. Patients receiving clopidogrel were also evaluated for clopidogrel resistance and grouped according to the results of this test. Assessments of platelet functions were performed by multiplate impedance aggregometry method and adenosine diphosphate test.

Results

The use of postoperative fresh blood replacement and platelet transfusion was higher in patients receiving clopidogrel than in those not receiving it (P=0.001, P=0.018). DM, HT, myocardial infarction, and the number of presentation to the emergency room were significantly higher in patients receiving clopidogrel than in those not receiving it (P<0.05). No significant difference was determined between patients with and without clopidogrel resistance regarding the amount of bleeding during and after surgery, erythrocyte suspension and fresh-frozen plasma transfusion rates, preoperative troponin values, ejection fraction values, and length of hospital stays (P>0.05).

Conclusion

We think that resistance studies in patients receiving clopidogrel before cardiac surgery are not efficient to predict bleeding and bleeding-related complications in patients undergoing emergency and elective CABG surgeries.

Blood Transfusion and Increased Perioperative Risk in Coronary Artery Bypass Grafts

OBJECTIVE

To correlate blood transfusions and clinical outcomes during hospitalization in coronary artery bypass grafting surgery (CABG).

METHODS

Transfusion, clinical and hematological data were collected for 1,378 patients undergoing isolated or combined CABG between January 2011 and December 2012. The effect of blood transfusions was evaluated through multivariate analysis to predict three co-primary outcomes: composite ischemic events, composite infectious complications and hospital mortality. Because higher risk patients receive more transfusions, the hospital mortality outcome was also tested on a stratum of low-risk patients to isolate the effect of preoperative risk on the results.

RESULTS

The transfusion rate was 63.9%. The use of blood products was associated with a higher incidence of the three coprimary outcomes: composite infectious complications (OR 2.67, 95% CI 1.70 to 4.19; P<0.001), composite ischemic events (OR 2.42, 95% CI 1.70 to 3.46; P<0.001) and hospital mortality (OR 3.07, 95% CI 1.53 to 6.13; P<0.001). When only patients with logistic EuroSCORE ≤ 2% were evaluated, i.e., low-risk individuals, the mortality rate and the incidence of ischemic events and infectious complications composites remained higher among the transfused patients [6% vs. 0.4% (P<0.001), 11.7% vs. 24,3% (P<0.001) and 6.5% vs. 12.7% (P=0.002), respectively].

CONCLUSION

The use of blood components in patients undergoing CABG was associated with ischemic events, infectious complications and hospital mortality, even in low-risk patients.

A Difference in Bleeding and Use of Blood and Blood Products in Patients who Were Preoperatively on Aspirin or Dual Antiplatelet Therapy Before Coronary Artery Bypass Grafting

Background

Postoperative bleeding in patients who underwent elective coronary artery bypass surgery (CABG) may increase due to preoperative anticoagulant therapy indicative of their disease - acute coronary syndrome or implanted coronary artery stent. Increased bleeding in many cases requires the use of blood and blood derivatives, and sometimes even reoperation. Their use poses the risk of complications, may extend the hospitalization.

Methods

Our observation retrospective study included 131 patients, 41 treated with aspirin and 90 treated with aspirin and clopidogrel. All underwent for the first time elective on-pump isolated CABG surgery at Clinic for cardiovascular surgery of Clinical Center University of Sarajevo, in period June 2016 to September 2017. The data were collected from patient's records.

Results

Out of 131 patients,73.3% were male. The average age was 62. The average total drainage during the first 48 postoperative hours in ASA group was 1027.4±404.9ml and 1049.8±371.3ml in DAPT group. The mean number of whole blood transfusions in the DAPT group washigher compared to ASAgroup. The average number of fresh frozen plasma were higher in the DAPT group 0.84±0.51 compared to the group ASA 0.39±0.07, as well the average thrombocytes transfusions were slightly higher in the DAPT group. Statistical analysis suggests that there is no significant difference between the observed groups (p>0.05). Also, our study did not show a statistically significant difference between arrhythmia onset, the length of mechanical ventilation, use of protamineand tranexamic acid. Reoperation due to postoperative bleeding was recorded in 2 cases in the DAPT group as well as 2 lethal cases.

Conclusion

In our study, we could not demonstrate less postoperative bleeding and use of blood and blood products in a group of patients who were preoperatively treated with aspirin compared to patients with dual antiplatelet therapy in the elective isolated CABG surgery.

Risks and benefits of giving early Aspirin within 6 hours of CABG: A retrospective analysis

BACKGROUND & OBJECTIVE

Antiplatelet drugs are frequently used after coronary artery bypass graft (CABG) surgery to prevent venous graft occlusion. The fear of bleeding complications prevents them to be given early post operatively, which is the time when antiplatelets use confers maximum benefit. Our objective was to determine the effect and influence of early aspirin therapy on fatal and nonfatal bleeding complications and blood requirements after coronary bypass surgery (CABG).

METHODS

The patients who only underwent coronary artery bypass surgery for the first time in the past three years and did not have any bleeding diathesis were retrospectively analyzed from the cardiac surgery database of CPEIC Multan. The patients either received aspirin within six hours of CABG or had it given after 12 hours. The patients were analyzed for mean blood loss and number of blood units transfused. SPSS was used for statistical analysis. P value < 0.05 was considered significant.

RESULTS

Total 281 patients received aspirin within six hours while 326 patients did not. Mean blood loss in early aspirin group was 727ml as compared to 767ml in the other group (p value 0.74). The median number of blood units transfused was 2 (p value 0.98). Our results did not show any statistical difference in both the groups.

CONCLUSION

Aspirin can safely be given early after CABG without the fear of bleeding complications thus conferring the advantage of increased graft patency.

Use of adenosine diphosphate receptor inhibitor prior to left ventricular assist device implantation is not associated with increased bleeding

Current guidelines recommend adenosine diphosphate receptor inhibitors (ADPRi) be discontinued 5-7 days prior to cardiac surgery due to increased bleeding events, rates of re-exploration, and transfusions. However, the risks of left ventricular assist device (LVAD) implantation in patients taking an ADPRi have not previously been studied. We retrospectively identified 134 eligible patients with ischemic cardiomyopathy that underwent LVAD implantation between July 2009 and August 2013. The cohorts received an ADPRi ≤5 days of surgery (n = 25) versus >5 days prior or not at all (n = 109). Subgroup analyses adjusted for differences in frequency of redo sternotomy between cohorts, excluded patients that received an ADPRi >1 year prior to surgery, and excluded patients with a redo sternotomy. The ADPRi and control groups did not have significant differences in the primary outcomes, intraoperative PRBC units transfused (3.0 vs. 4.0, p = 0.12) or chest tube output within 24 h of surgery (1.66 L vs. 1.80 L, p = 0.61). After adjusting for differences in frequency of redo sternotomy (ADPRi vs. control, 12 vs. 52%, p ≤ 0.001), no significant difference in PRBC units transfused (3.1 vs. 3.5, p = 0.59) or chest tube output (2.04 L vs. 2.04 L, p = 0.98) was seen. No significant difference in 30-day mortality (8.0 vs. 11.0%, p = 0.63), 90-day mortality (16.4 vs. 23.3%, p = 0.42), or length of stay (29.0 vs. 28.0, p = 0.61) was seen. In this single-center experience, use of an ADPRi ≤5 days prior to LVAD implantation was not associated with increased bleeding, length of stay, or mortality.

Impact of preoperative dual antiplatelet therapy on bleeding complications in patients with acute coronary syndromes who undergo urgent coronary artery bypass grafting

BACKGROUND

A 5- to 7-day washout period before coronary artery bypass grafting (CABG) is recommended for patients who have recently received a thienopyridine derivative; however, data supporting this guideline recommendation are lacking in Japanese patients.

METHODS

Urgent isolated CABG was performed in 130 consecutive patients with acute coronary syndromes (ACS) (101 men; mean age, 69 years). Urgent CABG was defined as operation performed within 5 days after coronary angiography. All patients continued to receive aspirin 100mg/day. The subjects were retrospectively divided into 2 groups: 30 patients with preoperative thienopyridine (clopidogrel in 15 patients, ticlopidine in 15) exposure within 5 days [dual antiplatelet therapy (DAPT) group] and 100 patients without exposure [single antiplatelet therapy (SAPT) group].

RESULTS

Although the DAPT group had a higher proportion of patients who received perioperative platelet transfusions than the SAPT group (50% vs. 18%, p<0.001), intraoperative bleeding (median, 1100ml; interquartile range, 620-1440 vs. 920ml; 500-1100) and total drain output within 48h after surgery (577±262 vs. 543±277ml) were similar. CABG-related major bleeding, which was defined as type 4 or 5 bleeding according to the Bleeding Academic Research Consortium definitions, occurred in a significantly higher proportion of patients in the DAPT group than in the SAPT group (20% vs. 3%, p=0.005). This difference in major bleeding was driven mainly by the higher rate of transfusion of ≥5U red blood cells within a 48-h period in the DAPT group (13% vs. 1%, p=0.01). There was no significant difference in the 30-day composite endpoint including death, myocardial (re)infarction, ischemic stroke, and refractory angina between the DAPT group and SAPT group (17% vs. 19%).

CONCLUSIONS

Preoperative DAPT increases the risk of CABG-related major bleeding in Japanese patients with ACS undergoing urgent CABG.

Impact of prior intracoronary stenting on late outcomes of coronary artery bypass surgery in diabetics with triple-vessel disease

OBJECTIVE

Recent studies have indicated that coronary artery bypass grafting (CABG) outcomes in patients with prior stents are suboptimal. We aimed to study the impact of prior percutaneous coronary intervention (PCI) with stenting (PCI-S) on late CABG mortality in diabetic patients with triple-vessel disease.

METHODS

We reviewed the primary nonemergency CABG experience from a single U.S. institution (n = 7005; 1996-2007, Toledo, Ohio). Diabetics with triple-vessel disease (n = 1583) were identified and divided into 2 groups: (1) prior PCI-S (n = 202); and (2) no prior PCI (No-PCI [n = 1381]). Hierarchic Cox proportional hazards models were used to assess the effect of prior PCI-S on 5-year mortality after CABG. A propensity score for PCI-S and No-PCI patients was derived using a nonparsimonious logistic regression and used to generate a 1:1 (PCI-S to No-PCI) matched cohort.

RESULTS

In model 1, after adjusting for preoperative clinical characteristics, medications, off-pump surgery, and isolated CABG surgery status, prior PCI-S was associated with a 39% increased risk of mortality (hazard ratio [HR] = 1.39, with 95% confidence interval [CI; 1.02, 1.90]; P = .04). Further adjustment for date of surgery (model 2) (HR = 1.39, with 95% CI [1.02, 1.91]; P = .04) or operative parameters (model 3) (HR = 1.38, with 95% CI [1.01, 1.88]; P = .046) did not alter the association. The 1:1 matched-cohort analysis confirmed the increased risk associated with PCI-S (HR = 1.61, with 95% CI [1.03, 2.51]; P = .037).

CONCLUSIONS

Patients who have both diabetes and triple-vessel disease, and have undergone prior PCI-S, have poorer long-term outcomes after CABG compared with those who have had no prior PCI-S.

Point-of-care platelet function testing predicts bleeding in patients exposed to clopidogrel undergoing coronary artery bypass grafting: Verify pre-op TIMI 45--a pilot study

BACKGROUND

Guidelines recommend delaying coronary artery bypass grafting (CABG) for 5 days after discontinuing clopidogrel. However, platelet function may recover quicker in certain individuals.

HYPOTHESIS

We hypothesized that perioperative measurement of platelet function with a point-of-care P2Y12 inhibitor assay could predict bleeding during CABG in patients exposed to clopidogrel.

METHODS

Verify Pre-Op TIMI 45 was a prospective pilot study of 39 patients on clopidogrel who subsequently underwent CABG. Preoperative on-treatment platelet reactivity was assessed with VerifyNow P2Y12 Reaction Units (PRU), with higher PRU indicating more reactive platelets. Outcomes were stratified by PRU quartiles, as well as prespecified cutpoints for the lowest quartile (PRU 173), a cutpoint for major bleeding determined by the Youden index using receiver operator curve analysis (PRU 207), and clopidogrel resistance (PRU 230).

RESULTS

Patients in higher PRU quartiles experienced smaller decreases in hemoglobin and hematocrit (P < 0.05 for all comparisons), less major bleeding (P = 0.021), and less major or minor bleeding (P = 0.003). Patients above the PRU 207 and 230 cutpoints had less chest-tube output (P = 0.041 and P = 0.012, respectively), less major bleeding (P = 0.005 and P = 0.036, respectively), and less major or minor bleeding (P = 0.013 and P < 0.001, respectively). By receiver operator curve analysis, preoperative PRU ≤ 207 discriminated between patients with and without major bleeding during surgery (area under the curve: 0.76, 95% confidence interval: 0.59-0.94, P = 0.018).

CONCLUSIONS

In this pilot study, we found that point-of-care platelet function assessment could predict bleeding in patients recently exposed to clopidogrel undergoing CABG.

Transfusion strategy: impact of haemodynamics and the challenge of haemodilution

Blood transfusion is associated with increased morbidity and mortality and numerous reports have emphasised the need for reduction. Following this there is increased attention to the concept of patient blood management. However, bleeding is relatively common following cardiac surgery and is further enhanced by the continued antiplatelet therapy policy. Another important issue is that cardiopulmonary bypass leads to haemodilution and a potential blood loss. The basic role of blood is oxygen transport to the organs. The determining factors of oxygen delivery are cardiac output, haemoglobin, and saturation. If oxygen delivery/consumption is out of balance, the compensation mechanisms are simple, as a decrease in one factor results in an increase in one or two other factors. Patients with coexisting cardiac diseases may be of particular risk, but studies indicate that patients with coexisting cardiac diseases tolerate moderate anaemia and may even benefit from a restrictive transfusion regimen. Further it has been shown that patients with reduced left ventricular function are able to compensate with increased cardiac output in response to bleeding and haemodilution if normovolaemia is maintained. In conclusion the evidence supports that each institution establishes its own patient blood management strategy to both conserve blood products and maximise outcome.

Bleeding outcomes in patients given clopidogrel within 5 days of robotic coronary artery bypass graft procedure

BACKGROUND

Current guidelines recommend that clopidogrel should be held for 5 days prior to coronary artery bypass graft (CABG) procedure. However, it is unknown if this recommendation should apply to robotic-assisted (rCABG), which is less invasive because it does not involve sternotomy and thus reduces the risk of bleeding.

OBJECTIVE

To compare postoperative bleeding for rCABG patients who were taking clopidogrel within 5 days of the procedure with those who were not taking clopidogrel.

METHODS

This was a retrospective cohort study conducted between January 1, 2012 and December 31, 2012 of consecutive patients undergoing rCABG. Patients were categorized into 2 groups based on whether or not clopidogrel was administered within 5 days prior to the date of surgery. The primary outcome measure was the occurrence of the Bleeding Academic Research Consortium (BARC) definition for CABG-related bleeding. The secondary outcome measure was a comparison of chest tube output during the first 24-hour postoperative period.

RESULTS

A total of 136 rCABG patients were included in the final analyses. Of these, 39 (29%) received clopidogrel within 5 days of surgery. CABG-related bleeding using the BARC definition occurred in 26% of patients who received clopidogrel and 8% of patients who did not (P = .011). Median chest tube output during the first 24-hour postoperative period was also greater in patients who received clopidogrel (900 vs 735 mL, P = .002).

CONCLUSIONS

The use of clopidogrel within 5 days of rCABG is associated with greater postoperative bleeding and chest tube output, as defined by the BARC criteria.

Decreased von Willebrand factor ristocetin cofactor activity and increased ADAMTS13 antigen increase postoperative drainage after coronary artery bypass grafting

OBJECTIVES

Routine coagulation tests and bleed-scores fail to identify patients at risk of excessive postoperative drainage following coronary artery bypass grafting (CABG). We sought to investigate whether lower von Willebrand factor (VWF) and higher ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) are associated with a high postoperative drainage after CABG.

METHODS

In the prospective cohort study, VWF antigen (VWF:Ag), VWF ristocetin cofactor (VWF:RCO), VWF collagen-binding (VWF:CB), ADAMTS13 antigen (ADAMTS13:Ag) and ADAMTS13 activity were measured on the day of elective on-pump CABG in 232 consecutive patients without a prior history of haemorrhagic diathesis, including von Willebrand disease (95% discontinued aspirin preoperatively). Postoperative drainage and blood product use were recorded.

RESULTS

A comparison of extreme drainage quartiles (n=56) showed that individuals with the highest drainage volumes have mean VWF:RCO lower by 19% (P<0.0001), median VWF:Ag lower by 19% (P<0.0001), ADAMTS13:Ag higher by 8% (P=0.0002), ADAMTS13 activity higher by 9% (P=0.01) and fibrinogen lower by 14% (P=0.03) than those with the lowest drainage. Linear regression analysis showed that preoperative VWF:RCO (b=-4.83, P=0.002) and fibrinogen (b=-61.52, P=0.04) are the only independent predictors of postoperative drainage. Multivariate logistic regression demonstrated that preoperative VWF:RCO in the lowest quartile and ADAMTS13:Ag levels in the highest quartile increased the risk of high (≥1000 ml) drainage (odds ratio [95% confidence interval]=4.88 [1.83-13.02], P=0.001 and 3.77 [1.49-9.52], P=0.005; respectively).

CONCLUSIONS

Patients undergoing elective CABG with lower preoperative VWF:RCO are at risk of having larger postoperative drainage, which suggests a novel contributor to increased perioperative bleeding in cardiac surgery.