Effect of Clopidogrel Premedication in Off-Pump Cardiac Surgery

Acute stroke in patients undergoing coronary artery bypass grafting surgery in acute coronary syndrome: Predictors and outcomes

OBJECTIVES

Coronary artery bypass grafting (CABG) surgery in patients with acute coronary syndrome (ACS) remains a high-risk procedure and is associated with adverse outcomes. The risk factors of acute stroke in the above-mentioned patients stay unclear and some appropriate data is lacking in the literature. Thus, we aimed to investigate the predictors of acute stroke in patients undergoing CABG surgery in ACS.

METHODS

The retrospective single-centre cohort analysis was conducted. All patients (n = 1344) who suffered from acute coronary syndrome and underwent CABG procedure at the University hospital Cologne from June 2011 until October 2019 were included in our study. In order to find the risk factors of acute stroke after bypass surgery, patients were divided into two groups (non-stroke group (n = 1297) and stroke group (n = 47)). In order to even above-mentioned groups propensity score matching (PSM) analysis was performed (non-stroke group (n = 46) and stroke group (n = 46).

RESULTS

Duration of cardiopulmonary bypass (p = .015) and cross clamp time (p = .006) were significantly longer in patients who suffered stroke. Perioperative myocardial infarction was significantly higher (p = .030) in the stroke group. Likewise, the duration of intensive care unit stay (p < .001) and in-hospital stay (p < .001) were significantly longer in patients with stroke. However, the mortality rate did not differ significantly (p = .131) between above-mentioned groups. Univariate and multivariate analysis showed cardiogenic shock (p = .003), peripheral vascular disease (PVD, p = .025) and previous stroke (p = .045) as relevant independent predictors for acute stroke after CABG procedure in patients with ACS.

CONCLUSION

Based on our findings, acute stroke after bypass surgery in patients with ACS is associated with increased mortality and adverse outcomes. Cardiogenic shock, peripheral vascular disease and previous stroke were independent predictors of stroke after CABG procedure. Therefore, preoperative evaluation of potential risk factors may be crucial to improve postoperative results.

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.

Impact of Clopidogrel Loading for Coronarography on Bleeding After Urgent First Time CABG

BACKGROUND

Excessive bleeding impairs outcome after coronary artery bypass grafting (CABG). Clopidogrel in combination with aspirin, given before percutaneous coronary intervention, have become the standard for stent thrombosis prevention. Some premedicated patients, however, are found to need surgical treatment, thus platelet inhibition caused by clopidogrel becomes a concern for post operation major bleeding.

AIMS

This study was designed to evaluate the impact of preoperative clopidogrel on bleeding and outcomes after coronary artery bypass graft surgery (CABG).

METHODS

The study represent a observational retrospective analysis of collected data. The follow up of 223 treated with clopidogrel and aspirin and 77 patients not receiving treatment with platelet antagonist 7 days before CABG are analyzed.

RESULTS

The groups were comparable in age, gender, body surface area, preoperative hematocrit, preoperative prothrombin time and prior myocardial infarction. The clopidogrel group had higher12h and 24h mean chest tube output (at 12h mean 519.7ml vs 353.1 ml, p < 0.05, at 24h mean 756.6 ml vs 563.5 ml, p<0.05). Moreover, reoperation for bleeding was 4.5-fold higher in the clopidogrel group (5.9% vs. 1.3%, p <0.01), and more transfusions of red blood cells (3.23U vs 2.6 U, p<0.05), platelets (1.53U vs 1.23U, p<0.01) and fresh frozen plasma (0.84U vs 0.36 U, p<0.01). The clopidogrel group also showed a longer mechanical ventilation time (16.9h vs 12.9 h p = 0.03) and trend towards more prolonged stay in ICU (2.08 days vs 1.7 days p= 0.048).

CONCLUSIONS

Clopidogrel in combination with aspirin before CABG is associated with higher postoperative bleeding, exposure to blood products and morbidity. These findings raise concern regarding the routine administration of clopidogrel before anticipated but undecided coronary stent implantation.

Clopidogrel and hip fractures, is it safe? A systematic review and meta-analysis

Background

Femoral neck fractures in the elderly make up a large proportion of Orthopaedic surgical admissions each year. Operating on patients with clopidogrel poses a challenge because of the risk of bleeding and the difficulty deciding the optimal timing of surgery. The aim of this systematic review is to examine the published evidence to establish a set of guidelines for approaching neck of femur patients who are on clopidogrel.

Methods

All comparative studies with an intervention group and a control group were considered. Data on patient blood transfusion exposures, units transfused, haemoglobin concentration and drop in haemoglobin were extracted and pooled using the fixed effects model. Heterogeneity of the intervention effect was assessed with the I² statistic.

Results

A total of 4219 studies were identified. After removal of duplicates and after exclusion criteria were applied, there were 14 studies to be included. All 14 were case series with controls. There was no significant heterogeneity amongst the studies. Pooled odds ratio for transfusion exposures was 1.24 (95 % confidence interval 0.91 to 1.71) however this was not statistically significant (p = 0.14). No significant mean differences were found for other primary outcome measures.

Conclusions

On the available evidence, we recommend that these patients can be managed by normal protocols with early surgery. Operating early on patients on clopidogrel is safe and does not appear to confer any clinically significant bleeding risk. As reported in other studies, we believe clopidogrel, if possible, should not be withheld throughout the perioperative period due to increased risk of cardiovascular events associated with stopping clopidogrel. Care should be taken intraoperatively to minimise blood loss due to the increased potential for bleeding.

Trial registration

This systematic review and meta-analysis has been registered on Research Registry on July 16, 2015. The Review Registry Unique Identifying Number is: reviewregistry61.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-016-0988-9) contains supplementary material, which is available to authorized users.

Local use of ankaferd blood clotter in emergent beating heart coronary artery bypass grafting

Background:

Severe beeding which requiring massive blood transfusion after emergent beating heart surgery is shown to be 1–3%. Therefore, complications and side effects of transfusion can be seen. The aim of this study was to investigate the effectiveness of Ankaferd blood clotter (ABC) as a new topical herbal blood clotter to decrease mediastinal bleeding in emergent beating heart CABG patients who medicated with clopidogrel and acetyl salisilic acite (ASA) prior to CABG surgery.

Materials and Methods:

25 CABG patients received a high dose clopidogrel (600 mgr) and 300 mgr ASA have been included into the study (ABC group). 25 patients have also been included into the study for comparison (placebo group, PG). After the administration of protamine sulphate, a 10 ml of ABC solution has been sprayed to the surgical area including mediastinum and epicardial sac. We compared mediastinal drenaige, reoperation due to tamponade, and required blood and blood products in both groups.

Results:

The mean amount of bleeding after operation was 230 ml in ABC group, and 490 ml in CG (P=0.001). In ICU, bleeding in ABC group and CG was 410ml and 680ml, respectively (P=0.0022). The mean total bleeding from mediastinum was 530±280 mL and 990±440 mL In ABC and CG group, respectively (P=0.001). The amount of autotransfusion was as follows: 175 mL in ABC group, and 290 mL in CG (P=0.002). No patient needed the surgical revision in ABC group, but four patients (16%) from CG group because of cardiac tamponade. Seventeen patients from CG required blood transfusion due to low hematocrite level postoperatively. In CG, the mean hematocrite level was 17±2,3. Transfusion of fresh frozen plasma and platelets in ABC group and CG were as follows: 0.2 and 0 in ABC group, and 0.3and 0.4 in CG.

Conclusion:

Our study showed that the local use of 10 mL ABC reduces bleeding significantly. Therefore, transfusion requirements of PRBC, platelets, and total blood units in patients on clopidogrel and ASA undergoing emergent beating heart CABG. To provide cardiac tamponade because of excessive mediastinal bleeding and requirement of blood transfusion after emergent CABG patients who previously administered clopidogrel and ASA, we propose local use of ABC solution as a potent coagulant agent.

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.

Perioperative stroke: risk assessment, prevention and treatment

OPINION STATEMENT

Numerous risk factors for perioperative stroke have been identified and many are modifiable. Surgical patients with a history of cerebrovascular disease should be evaluated by a neurologist. Cardiac and cerebrovascular testing is critical in identifying patients at high risk for perioperative stroke. The identification and treatment of carotid disease in the context of upcoming surgery has been a source of controversy. Routine carotid revascularization performed with coronary artery bypass graft (CABG) surgery for incidentally discovered carotid stenosis is not recommended. Prior to aortic manipulation during CABG, epiaortic ultrasound should be performed to identify aortic atheromatous plaques. If possible, preoperative aspirin, beta blocker, statin, and angiotensin converting-enzyme (ACE) inhibitor therapy should be continued in the perioperative period. Patients who are prescribed anticoagulation at high risk of thromboembolism should receive bridging anticoagulation during the perioperative period. The identification and prevention of postoperative atrial fibrillation (AF) is central to stroke prevention. CABG patients should be initiated on beta blockade +/- amiodarone to prevent postoperative AF. Many practitioners have been traditionally nihilistic towards acute perioperative stroke treatment. Given the narrow therapeutic window of treatment options, candidacy is dependent on timely recognition. Intravenous and endovascular thrombolysis/therapies are viable options in selected patients under the guidance and expertise of a neurologist. This article will present the epidemiology of perioperative stroke, the pathophysiology, risk assessment and stratification for common surgeries. The article will additionally focus on treatment options including modifiable risk factor reduction and the perioperative management of medications.

The influence of hypothermia on transfusion requirement in patients who received clopidogrel in proximity to off-pump coronary bypass surgery

PURPOSE

Hypothermia adversely affects the coagulation that could be of clinical significance in patients receiving clopidogrel. We evaluated the influence of hypothermia on transfusion requirements in patients undergoing isolated off-pump coronary artery bypass surgery (OPCAB) who continued clopidogrel use within 5 days of surgery.

MATERIALS AND METHODS

Protocol-based, prospectively entered data of 369 patients were retrospectively reviewed. The time-weighted average of intraoperative temperatures and the temperature upon ICU admission (TWA-temp) was assessed. Patients were divided into normothermia (≥36°C, n=224) and hypothermia (<36°C, n=145) group. The transfusion requirement for perioperative blood loss was assessed and compared.

RESULTS

Patients with hypothermia were older and had lower body surface area (BSA) than patients with normothermia. Age and BSA adjusted transfusion requirement was significantly larger in the hypothermia group [patients requiring transfusion: 64% versus 48%, p=0.003; number of units: 0 (0-2) units versus 2 (0-3) units, p=0.002]. In multivariate analysis of predictors of perioperative multiple transfusion requirements, hypothermia was identified as an independent risk factor along with age, female gender, BSA, chronic kidney disease, and congestive heart failure.

CONCLUSION

Hypothermia was associated with increased transfusion requirement in patients undergoing OPCAB who received clopidogrel in proximity to surgery. Considering the high prevalence and the possibility of hypothermia being a modifiable risk factor, aggressive measures should be undertaken to maintain normothermia in those patients.

Optimal anticoagulation during off pump coronary artery bypass in patients recently exposed to clopidogrel

PURPOSE

The aim of this study was to find an optimal range of activated clotting time (ACT) during off-pump coronary artery bypass surgery (OPCAB) yielding ischemic protection without the risk of hemorrhagic complications in patients with recent exposure to dual antiplatelet therapy.

MATERIALS AND METHODS

Three hundred and five patients who received aspirin and clopidogrel within 7 days of isolated multi-vessel OPCAB were retrospectively studied. Combined hemorrhagic and ischemic outcome was defined as the occurrence of 1 of the following: significant perioperative bleeding (>30% of estimated blood volume), transfusion of packed red blood cell (pRBC) ≥ 2 U, or myocardial infarction (MI). This was compared in relation to the tertile distribution of the time-weighted average ACT-212-291 sec (first tertile), 292-334 sec (second tertile), 335-485 sec (third tertile).

RESULTS

The amount of perioperative blood loss was 937 ± 313 mL, 1014 ± 340 mL, and 1076 ± 383 mL, respectively (p=0.022). Significantly more patients in the third tertile developed MI (4%, 4%, and 12%, respectively, p=0.034). The incidence of significant perioperative blood loss and transfusion of pRBC ≥ 2 U were lower in the first tertile than those of other tertiles without statistical significance. In the multivariate analysis, the first tertile was associated with a 52% risk reduction of combined hemorrhagic and ischemic outcomes (95% confidence interval: 0.25-0.92, p= 0.027).

CONCLUSION

A lower degree of anticoagulation with a reduced initial heparin loading dose should be carefully considered for patients undergoing OPCAB who have recently been exposed to clopidogrel.

Longer in-hospital wait times do not result in worse outcomes for patients requiring urgent coronary artery bypass graft surgery

BACKGROUND

In certain health care systems, patients wait for non-emergency services. Although waiting may not be considered acceptable, the delay may allow for patient optimization, such as giving time for "toxic" agents to be cleared, that could improve outcomes. We sought to determine the relationship between wait times and outcomes in in-hospital patients undergoing urgent coronary artery bypass graft (CABG) surgery.

METHODS AND RESULTS

A prospectively collected database of consecutive, medically urgent, but clinically stable patients undergoing CABG surgery from 1995 to 2007, was analyzed. A total of 3067 patients with need for urgent CABG surgery with various in-hospital wait times (n = 440, 0-2 days; n = 799, 3-5 days; n = 1317, 6-10 days; n = 511, 11-15 days) were included. There were no differences in mortality, intensive care unit (ICU) or post-surgery hospital length of stay (LOS) among the patient groups. Multivariate logistic regression analysis revealed that wait time was not associated with mortality (P = 0.625). Due to changes in the nonsurgical management of coronary artery disease, a separate analysis of patients, from 2002 to 2007, was also performed to explore contemporary results. In the latter subset, 1495 patients (n = 175, 341, 720, 259, in the same 4 respective wait-time groups) were included; the 0-2 days patient group underwent more blood transfusions (50% vs 38%; P = 0.01), prolonged ventilation (6% vs 2%; P = 0.05), post-operative dialysis (2% vs 0%; P = 0.08), and longer ICU LOS (26 vs 23 hours; P = 0.02) compared with the 3-5 days patient group. The Society of Thoracic Surgeons mortality risk scores of the 0-2 days and 3-5 days groups were the same (1.5%). Multivariate regression analysis revealed that increased wait time was associated with fewer patients requiring blood transfusion (P < 0.05) for CABG surgery.

CONCLUSION

Waiting for in-hospital urgent CABG surgery does not lead to worse patient outcomes and may, in fact, reduce the procedural and medical risks of postoperative blood transfusions, prolonged ventilation, dialysis, and shorten ICU LOS.

The effect of combined clopidogrel and aspirin therapy after off-pump coronary surgery: a pilot study

OBJECTIVE

: The purpose of this randomized study was to evaluate the effect on graft patency by adding clopidogrel to aspirin in off-pump coronary artery bypass (OPCAB) grafting and the possible side effects of such therapy.

METHODS

: Twenty patients who underwent standard OPCAB through median sternotomy were randomized immediately after surgery in two groups. Patients in group A (n = 10) received 100 mg of aspirin starting preoperatively, continuing indefinitely. Patients in group B received 100 mg of aspirin and, in addition, 75 mg of clopidogrel starting immediately after the operation and for 3 months. Postoperative bleeding and other perioperative parameters were compared. Angiography was repeated 3 months after surgery to determine the patency and quality of grafts.

RESULTS

: Preoperative risk factors were similar in the two groups. There was no significant difference in average number of distal anastomosis (P = 0.572), operation time (P = 0.686), postoperative bleeding (P = 0.256), ventilation time (P = 0.635), and intensive care unit stay (P = 0.065). Length of stay was shorter in group B (P = 0.024). There was no postoperative complication in either groups. Eight of 27 grafts in group A and 2 of 29 grafts in group B (P = 0.037) were occluded at the time of control angiography.

CONCLUSIONS

: Early administration of a combined regimen of clopidogrel and aspirin after OPCAB grafting is not associated with increased postoperative bleeding or other major complications. Despite the small number of patients in this study and small number of examined grafts, the results suggest that the addition of clopidogrel may increase graft patency after OPCAB grafting.

Platelet function measurement-based strategy to reduce bleeding and waiting time in clopidogrel-treated patients undergoing coronary artery bypass graft surgery: the timing based on platelet function strategy to reduce clopidogrel-associated bleeding related to CABG (TARGET-CABG) study

BACKGROUND

Aspirin and clopidogrel therapy is associated with a variable bleeding risk in patients undergoing coronary artery bypass graft surgery (CABG). We evaluated the role of platelet function testing in clopidogrel-treated patients undergoing CABG.

METHODS AND RESULTS

One hundred eighty patients on background aspirin with/without clopidogrel therapy undergoing elective first time isolated on-pump CABG were enrolled in a prospective single-center, nonrandomized, unblinded investigation (Timing Based on Platelet Function Strategy to Reduce Clopidogrel-Associated Bleeding Related to CABG [TARGET-CABG] study) between September 2008 and January 2011. Clopidogrel responsiveness (ADP-induced platelet-fibrin clot strength [MA(ADP)]) was determined by thrombelastography; CABG was done within 1 day, 3-5 days, and >5 days in patients with an MA(ADP) >50 mm, 35-50 mm, and <35 mm, respectively. The primary end point was 24-hour chest tube drainage and key secondary end point was total number of transfused red blood cells. Equivalence was defined as ≤25% difference between groups. ANCOVA was used to adjust for confounders. Mean 24-hour chest tube drainage in clopidogrel-treated patients was 93% (95% confidence interval, 81-107%) of the amount observed in clopidogrel-naive patients, and the total amount of red blood cells transfused did not differ between groups (1.80 U versus 2.08 U, respectively, P=0.540). The total waiting period in clopidogrel-treated patients was 233 days (mean, 2.7 days per patient).

CONCLUSIONS

A strategy based on preoperative platelet function testing to determine the timing of CABG in clopidogrel-treated patients was associated with the same amount of bleeding observed in clopidogrel-naive patients and ≈50% shorter waiting time than recommended in the current guidelines.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00857155.

Impact of clopidogrel on bleeding complications and survival in off-pump coronary artery bypass grafting

This study investigated the impact of preoperative clopidogrel on bleeding complications and survival during and after off-pump coronary artery bypass grafting (OPCABG) and assessed the possible role of the antifibrinolytic agent aprotinin for attenuating blood loss after clopidogrel exposure. Prospectively collected data of 753 consecutive adult patients undergoing OPCABG were retrospectively reviewed; 139 (18.5%) patients received clopidogrel preoperatively. Statistical methods used were student paired t-test, Mann-Whitney U, Kruskal-Wallis, chi-square analysis and Kaplan-Meier with log-rank analysis. Clopidogrel was associated with a significant increase in perioperative blood loss (P = 0.003) and more excessive postoperative haemorrhage (P = 0.04). Overall transfusion rates (P = 0.02) and the amount of administered blood products (P = 0.01) were also higher after clopidogrel exposure. Intraoperative aprotinin reduced postoperative bleeding significantly in patients administered clopidogrel [18.7% after 24 h (P = 0.006) and 15.2% after 48 h (P = 0.03)] and attenuated excessive postoperative haemorrhaging. Five-year survival was markedly improved in clopidogrel-treated patients. Preoperative clopidogrel exposure does increase perioperative blood loss and blood transfusion requirements in patients undergoing OPCABG but has an otherwise excellent safety profile with a 94% 5-year survival rate. Aprotinin attenuated this blood loss. Based on these results a recommendation to discontinue clopidogrel prior to coronary artery bypass grafting cannot be maintained, if OPCABG strategies are considered.

Effect of tranexamic acid on transfusion requirement in dual antiplatelet-treated anemic patients undergoing off-pump coronary artery bypass graft surgery

BACKGROUND

Anemia is not rare in patients presenting for coronary artery bypass graft surgery (CABG) and as these patients are frequently on dual antiplatelet therapy (DAPT), the coexisting conditions could potentially increase the risk of bleeding and transfusion. The aim of this study was to evaluate the effect of tranexamic acid (TA) on blood loss and transfusion in preoperatively anemic patients who continued DAPT until within 5 days of off-pump CABG (OPCAB).

METHODS AND RESULTS

Seventy-six anemic patients were randomized into 2 groups: TA group receiving TA (1g bolus followed by infusion at 200mg/h) and a Control group receiving the same volume of saline. The amount of blood loss and transfusion requirement during, and at 4 and 24h after the operation were assessed. Patients' characteristics and operative data were similar between the groups. During the perioperative period, which combined the intraoperative and postoperative 24h data, the TA group received significantly smaller amounts of packed red blood cells and fresh frozen plasma. Total amount of perioperative blood loss was similar between the groups, although the blood loss during the postoperative 4h was significantly less in the TA group.

CONCLUSIONS

TA infusion could reduce the amount of transfusion during the perioperative period in patients with preoperative anemia who continue DAPT until within 5 days of OPCAB.

Managing adverse effects and drug-drug interactions of antiplatelet agents

Antiplatelet therapies have reduced the frequency of adverse events associated with plaque rupture in several clinical situations. These therapies include established antiplatelet agents (such as aspirin, clopidogrel, or glycoprotein IIb/IIIa inhibitors) as well as new agents (such as prasugrel and ticagrelor). In this Review, we address the most important adverse events of antiplatelet therapy, including hemorrhage, hematologic reactions, and dyspnea. We discuss strategies to reduce the incidence of complications and outline potential methods to manage adverse reactions. Interactions between antiplatelet agents and other drugs--such as proton-pump inhibitors, calcium-channel blockers, statins, warfarin, or NSAIDs--are also addressed, as well as specific issues relating to the use of antiplatelet therapies in elderly patients.

Perioperative management of antiplatelet-drugs in cardiac surgery

The management of coronary patients scheduled for a coronary artery bypass grafting (CABG), who are receiving one or more antiplatelet drugs, is plenty of controversies. It has been shown that withdrawal of antiplatelet drugs is associated with an increased risk of a thrombotic event, but surgery under an altered platelet function also means an increased risk of bleeding in the perioperative period. Because of the conflict recommendations, this review article tries to evaluate the outcome of different perioperative antiplatelet protocols in patients with coronary artery disease undergoing CABG.

Safety of carotid endarterectomy while on clopidogrel (Plavix)

Object

Many patients undergoing carotid endarterectomy (CEA) regularly take clopidogrel, a permanent platelet inhibitor. The authors sought to determine whether taking clopidogrel in the period before CEA leads to more bleeding or other complications.

Methods

The authors performed a retrospective, institutional review board–approved review of 182 consecutive patients who underwent CEA. Clinical, radiographic, and surgical data were gleaned from hospital and clinic records. Analysis was based on the presence or absence of clopidogrel in patients undergoing CEA and was performed twice by considering clopidogrel use within 8 days and within 5 days of surgery to define the groups.

Results

Taking clopidogrel within 8 days before surgery resulted in no statistical increase in any measure of morbidity or death. Taking clopidogrel within 5 days was associated with a small but significant increase in operative blood loss and conservatively managed postoperative neck swelling. No measure of permanent morbidity or death was increased in either clopidogrel group.

Conclusions

Findings in this study support the safety of preoperative clopidogrel in patients undergoing CEA.

Primer on statistical interpretation or methods report card on propensity-score matching in the cardiology literature from 2004 to 2006: a systematic review

BACKGROUND

Propensity-score matching is frequently used in the cardiology literature. Recent systematic reviews have found that this method is, in general, poorly implemented in the medical literature. The study objective was to examine the quality of the implementation of propensity-score matching in the general cardiology literature.

METHODS AND RESULTS

A total of 44 articles published in the American Heart Journal, the American Journal of Cardiology, Circulation, the European Heart Journal, Heart, the International Journal of Cardiology, and the Journal of the American College of Cardiology between January 1, 2004, and December 31, 2006, were examined. Twenty of the 44 studies did not provide adequate information on how the propensity-score-matched pairs were formed. Fourteen studies did not report whether matching on the propensity score balanced baseline characteristics between treated and untreated subjects in the matched sample. Only 4 studies explicitly used statistical methods appropriate for matched studies to compare baseline characteristics between treated and untreated subjects. Only 11 (25%) of the 44 studies explicitly used statistical methods appropriate for the analysis of matched data when estimating the effect of treatment on the outcomes. Only 2 studies described the matching method used, assessed balance in baseline covariates by appropriate methods, and used appropriate statistical methods to estimate the treatment effect and its significance.

CONCLUSIONS

Application of propensity-score matching was poor in the cardiology literature. Suggestions for improving the reporting and analysis of studies that use propensity-score matching are provided.

The management of patients with hip fractures who are taking Clopidogrel

AIM

To assess the outcomes of patients with acute proximal hip fractures who were taking Clopidogrel.

METHOD

A retrospective study of 135 patients with proximal hip fractures. Demographic data and clinical outcomes were collected via review of hospital medical records.

RESULTS

21 patients taking Clopidogrel on admission were compared with 114 patients not on Clopidogrel. The groups were similar in their baseline characteristics. Postoperative haemoglobin and wound haematoma, hospital length of stay and death rate were similar in both groups even when the patients on Clopidogrel were operated on within 2 days of fracture. Days to surgery were longer in the Clopidogrel group than the control group (3.5 vs 0.9).

CONCLUSIONS

This study demonstrated that patients on Clopidogrel do not have a worse outcome than those who were not taking the medication. We feel that it is safe to perform surgery as soon as possible.

Decision making after aspirin, clopidogrel and GPIIb/IIIa inhibitor use

The expanding use of antiplatelet agents in patients who undergo coronary bypass grafting raises the problem of balancing the benefit of this treatment and the risk of increased bleeding after surgery. Aspirin and clopidogrel have different mechanisms of actions, but have in common the irreversibility of the inhibition mechanism. Even if platelets half-life is around 10 days, it is not necessary to wait for this period of time. It can be reasonable to discontinue aspirin two to three days and clopidogrel five days before surgery, even if it was recently suggested to reduce the discontinuation interval to two to three days for the clopidogrel as well. GPIIb/IIIa inhibitors have a short acting action. Reasonably, abciximab has to be stopped, when possible, at least 12 hours before surgery, preferably before 24 hours. On the contrary, tirofiban can also be stopped at the moment of skin incision without harmful effects. Very little is known of eptifibatide, but it seems that it is safe to stop it two to four hours before surgery. Patients with acute coronary syndrome do not need to discontinue any antiplatelet treatment.

Reoperation for bleeding in patients undergoing coronary artery bypass surgery: incidence, risk factors, time trends, and outcomes

BACKGROUND

Reoperation for bleeding represents an important complication in patients undergoing coronary artery bypass surgery (CABG). Yet, few studies have characterized risk factors and patient outcomes of this event.

METHODS AND RESULTS

We evaluated 528 686 CABG patients at >800 hospitals in the Society of Thoracic Surgeons National Cardiac Database (2004 to 2007). Clinical features and in-hospital outcomes were evaluated in patients with and without reoperation for bleeding after CABG. Logistic regression was used to identify predictors of risk of this event and to estimate weights for an additive risk score. A total of 12 652 CABG patients (2.4%) required reoperation for bleeding. These rates remained fairly stable over time (2.2%, 2.3%, 2.5%, and 2.4% from 2004 to 2007, respectively). Although overall operative mortality was 4.5-fold higher in patients requiring reoperation for bleeding versus those who did not (2.0% versus 9.1%), this mortality risk declined significantly over time (11.3%, 9.5%, 8.8%, and 8.2% from 2004 to 2007, respectively, P for trend=0.0006). Factors associated with higher risk for reoperation were identified by multivariable analysis (c statistic=0.60) and summarized into a simple bedside risk score. The risk-score performed well when tested in the validation set (Hosmer-Lemeshow P=0.16).

CONCLUSIONS

Reoperation for bleeding remains an important morbid event after CABG. Nonetheless, death in patients with this complication has decreased over time. Our risk tool should allow estimation of patients risk for reoperation for bleeding and promote preventive measures when feasible in this at-risk group.

Clinical outcomes with off-pump coronary surgery after angioplasty with stent

INTRODUCTION AND OBJECTIVES

The aim was to determine whether prior coronary stent implantation affects postoperative outcomes in patients undergoing coronary artery bypass grafting.

METHODS

Between January 2005 and April 2008, a retrospective analysis was carried out to evaluate the effect of prior coronary stent implantation in patients undergoing off-pump coronary surgery on the incidence of major cardiovascular events in the postoperative period (i.e. at 30 days or during postoperative hospitalization).

RESULTS

In total, 796 consecutive patients underwent coronary artery bypass grafting. Of these, 116 (14.6%) had a coronary stent at the time of surgery. Patients with and without stents had similar levels of risk (i.e. EuroSCORE). Multivariate analysis, adjusted for the presence of confounding variables (i.e. preoperative left ventricular ejection fraction <40%, critical preoperative state, age, history of cerebrovascular accident, recent acute myocardial infarction, number of diseased coronary vessels, incomplete revascularization and on-pump conversion), showed that the presence of a stent was significantly associated with increased risks of postoperative myocardial infarction (relative risk [RR]=3.13; 95% confidence interval [CI], 1.75-5.96), in-hospital cardiac mortality (RR=4.62; 95% CI, 1.76-12.11) and in-hospital all-cause mortality (RR=3.65; 95% CI, 1.60-8.34).

CONCLUSIONS

In our experience, coronary artery stent implantation prior to coronary surgery was associated with increased risks of postoperative myocardial infarction, cardiac mortality and all-cause mortality in the postoperative period.