Procedural Anticoagulation Research Articles

Dental management of patients taking novel oral anticoagulants (NOAs): Dabigatran.

BackgroundA new group of oral anticoagulants (dabigatran, rivaroxaban, apixaban and edoxaban) with clear advantages over classic dicoumarin oral anticoagulants (warfarin and acenocoumarol) has been developed in recent years. Patients being treated with oral anticoagulants are at higher risk for bleeding when undergoing dental treatments.Material and MethodsA literature search was conducted through April 2016 for publications in the ISI Web of Knowledge, PubMed and Cochrane Library using the keywords “dabigatran”, “rivaroxaban”, “apixaban”, “edoxaban”, “new oral anticoagulants”, “novel oral anticoagulants”, “bleeding” and “dental treatment”.ResultsThere is no need for regular coagulation monitoring of patients on dabigatran therapy. Whether or not to temporarily discontinue dabigatran must be assessed according to the bleeding risk involved in the dental procedure to be performed.ConclusionsThe number of patients under treatment with new oral anticoagulants will increase in the coming years. It is essential to know about the pharmacokinetics and pharmacodynamics of new oral anticoagulants and about their interactions with other drugs. It is necessary to develop clinical guidelines for the perioperative and postoperative management of these new oral anticoagulants in oral surgical procedures, and to carefully evaluate the bleeding risk of dental treatment, as well as the thrombotic risk of suppressing the new oral anticoagulant. Key words:Dabigatran, rivaroxaban, apixaban, edoxaban, novel oral anticoagulants, bleeding.

Bleeding and Thrombotic Outcomes Following Perioperative Interruption of Direct Oral Anticoagulants in Patients with Prior Venous Thromboembolic Disease

▪Introduction: The use of Direct Oral Anticoagulants (DOACs) for the prevention and treatment of Venous Thromboembolic Disease (VTE) is increasingly common. Patients on longstanding anticoagulation for the prevention of VTE frequently undergo invasive procedures that necessitate interruption of anticoagulation in order to avoid excessive bleeding during the procedure. There is little evidence surrounding the safety of perioperative DOAC interruption in patients with VTE.Methods: This study represents a retrospective analysis of adult patients on DOAC therapy for prior VTE, who underwent temporary interruption of anticoagulation therapy for inpatient or outpatient invasive procedures. The timing to hold and resume DOAC anticoagulation was based on the estimated half-life of the DOAC, as well as the bleeding risk of the procedure (Standard vs High). Our primary outcomes included the 30-day thromboembolic complication rate, as well as the 30-day major bleeding rate (ISTH non-surgical and surgical major bleeding criteria). Secondary outcomes included clinically relevant non-major bleeding (CRNMB) and overall mortality.Results: To date, a total of 87 patients have been included in the analysis, 68% of which were male. The mean age of the cohort was 58.3 years. All patients were on DOAC anticoagulation for acute treatment or secondary prevention of recurrent VTE. A large majority of patients (94%) were anticoagulated with rivaroxaban. Procedures were performed on an inpatient or outpatient basis in 24 and 63 patients, respectively. Forty six patients underwent procedures with standard bleeding risk. Mean time to anticoagulation discontinuation for standard and high bleeding risk procedures was 41.3 (SD = 20.8) and 49.3 (SD = 17.7) hours, respectively. The 30-day thromboembolic complication rate was 1.2% (95% CI: 0.2 to 6.2%), whereas the 30-day major bleeding rate was 0% (95% CI: 0 to 4.2%). The rate of CRNMB was 3.5% (95% CI: 1.2 to 9.7%). Overall mortality was 0% (95% CI: 0 to 4.2%).Conclusion: The perioperative interruption of direct oral anticoagulation for invasive procedures in patients with prior VTE appears to be associated with a relatively low risk of major bleeding, as well as recurrent VTE. Prospective studies are needed to evaluate the benefits and risks of perioperative interruption of direct oral anticoagulation in patients with prior VTE. DisclosuresCarrier:BMS: Research Funding; Leo Pharma: Research Funding.

Real-life experience with a new anticoagulation regimen for patients undergoing left-sided ablation procedures

BackgroundCurrent guidelines for anticoagulation during left-sided procedures recommend the administration of unfractionated heparin (UFH) with an initial bolus of 50–100 U/kg, followed by continuous infusion to maintain an activated clotting time (ACT) ≥ 300 s. Our objective was to compare the effectiveness of this standard regimen (100 U/kg bolus) to a more aggressive approach (200 U/kg bolus). MethodsWe collected data on a series of consecutive patients undergoing left sided ablation procedures. Patients with an INR ≥2.0 on the day of the procedure were excluded. Procedural anticoagulation was performed using one of two UFH regimens: 1) 100 U/kg bolus, followed by 10 U/kg/hour infusion or 2) 200 U/kg bolus, followed by 20 U/kg/hour infusion. ACT was measured 10 min after the second bolus and then controlled every 20 min. Heparin was titrated throughout the procedure to maintain an ACT 300–400 s. Results145 consecutive patients were included in the study: 34 received an initial bolus of 100 U/kg and 111 received 200 U/kg. The mean time required to reach an ACT ≥300 s was 15.25 min (95% CI 12.97–17.03) in the 200 U/kg group and 51.23 min (95% CI 40.65–61.81) in the 100 U/kg group (p < 0.001). There was no difference between groups with regard to thromboembolic or hemorrhagic complications. ConclusionCurrent anticoagulation guidelines for left-sided ablation procedures almost universally fail to achieve an initial ACT ≥300 s. A 200 U/kg heparin bolus is much more effective to promptly reach the target ACT, with a low rate of overshoot.

A Bridge to Nowhere? Benefits and Risks for Periprocedural Anticoagulation in Atrial Fibrillation.

In patients with atrial fibrillation (AF), oral anticoagulation is used to prevent stroke and systemic embolism. In a common clinical scenario, AF patients frequently undergo invasive procedures requiring temporary interruption of oral anticoagulation, thereby potentially exposing such patients to increased risk of thromboembolism. Bridging anticoagulation has been used clinically to mitigate this perceived thromboembolic risk, though this practice may also increase risk of periprocedural bleeding. High-quality data has not previously existed to inform decision-making in this clinical situation of bridging anticoagulation. We discuss recent results from the BRIDGE trial and secondary analyses from recent phase 3 randomized clinical trials of direct-acting oral anticoagulant (DOAC) use in non-valvular AF, that inform periprocedural anticoagulation with bridging strategies in AF patients. Updated data from these current trials favor against a strategy of bridging anticoagulation for elective procedures in the majority of AF patients, low or moderate in thromboembolic risk. Bridging anticoagulation is associated with an increased risk of bleeding and no decreased risk of thromboembolism.

Preoperative Patient and Institutional Factors Influence Anaesthetic Type in Foot and Ankle Surgery

Category: Other Introduction/Purpose: Lower-extremity orthopaedic procedures may be performed under regional or general anaesthesia, or a combination of techniques. There is a growing body of evidence outlining benefits of regional anaesthesia, with meta-analyses of randomized controlled trials and registry data suggesting decreases in surgical site infections, thromboembolism, cardiopulmonary complications and length of stay associated with regional anaesthesia. In patients undergoing foot and ankle surgery specifically, the literature demonstrates decreased pain, nausea, vomiting, opioid use and unplanned hospital admission. This supports increased use of regional anaesthesia in patients undergoing foot and ankle surgery. However, the type of anaesthetic used is dependent on surgeon, patient, anaesthesiologist and institutional factors. The purpose of this study is to investigate pre-operative factors that predict anaesthetic type in patients undergoing foot and ankle surgery. Methods: Data was collected prospectively on 888 patients undergoing foot or ankle surgery at a single institution. The primary method of anaesthesia for each procedure was recorded. Ten additional variables were recorded and analyzed: age, BMI, gender, diabetes, ASA status, procedure length, procedure start time, elective vs. trauma procedure, primary vs. revision procedure and preoperative anticoagulation. Logistic regression modelling was performed to identify factors that independently predict the type of anaesthetic used. Results: General anaesthetic was employed in 280 patients (32%), and regional anaesthesia was the primary anaesthetic type used in 608 (68%). Logistic regression modelling demonstrated that factors that independently predict use of general anaesthetic include younger age (p &lt; 0.0001; Odds Ratio 0.97/year), male sex (0.0033; 1.618), procedure start time (0.0319; 1.066/hour) and length of procedure ( &lt; 0.0001; 1.520/hour). Patients who underwent general anaesthetic had a mean length of procedure of 108 ± 77 minutes, whereas patient provided with regional anaesthesia had a mean length of procedure 83 ± 64 minutes. Conclusion: With increasing evidence supporting use of regional anaesthesia, it is important to identify modifiable factors that contribute to patients receiving alternative treatments. Since later procedure start time was identified as an independent predictor of general anaesthetic use, there may be a role for identifying patients at increased risk of complications associated with general anaesthesia and scheduling earlier start times. Furthermore, while it is logical that extended length of procedure is a contraindication to regional anaesthesia, the mean procedure time of 108 minutes in the general anaesthesia group indicates that many of these patients should still be candidates for regional anaesthesia.

Cerebral Embolism During Transcatheter Aortic Valve Replacement: The BRAVO-3 MRI Study

BackgroundCerebral embolization is a frequent complication after transcatheter aortic valve replacement (TAVR). We hypothesized that cerebral embolization may be reduced by anticoagulation with bivalirudin during TAVR. ObjectivesThis study sought to determine the proportion of patients with new cerebral embolus after TAVR and to investigate whether parenteral procedural anticoagulation strategies affect cerebral embolization. MethodsThe BRAVO (Effect of Bivalirudin on Aortic Valve Intervention Outcomes)-3 randomized trial compared bivalirudin with unfractionated heparin in patients undergoing transfemoral TAVR. A prospective cerebral magnetic resonance imaging (MRI) substudy was conducted in 4 sites; 60 patients were imaged with brain MRI after TAVR. Primary endpoint was proportion of patients with new cerebral emboli on MRI. Secondary endpoints included quantitative MRI analyses of cerebral lesions and neurological outcomes at 48 h and 30 days. ResultsPatients were randomized to bivalirudin (n = 29) versus heparin (n = 31). The proportion of patients with new cerebral emboli on MRI did not differ between bivalirudin and heparin groups (65.5% vs. 58.1%; p = 0.55). Groups were similar for median number of emboli per patient (1 [interquartile range (IQR): 0 to 3] vs. 1 [IQR: 0 to 1]; p = 0.08), total volume of emboli (45 [IQR: 0 to 175] mm3 vs. 33 [IQR: 0 to 133] mm3; p = 0.86), or proportion of patients with a clinical neurological deficit at 48 h or 30 days. All patients who presented clinically with stroke had evidence of new emboli on MRI. ConclusionsThis study documented cerebral embolization in nearly two-thirds of patients during contemporary TAVR. There were no significant differences in cerebral embolization for bivalirudin versus heparin anticoagulation during TAVR. (Open-Label, Randomized Trial in Patients Undergoing TAVR to Determine Safety and Efficacy of Bivalrudin vs. UFH [BRAVO-2/3]; NCT01651780)

Abstract 34: Low SpO 2 and Lack of Heparin are Associated With Cardiac Catheterization-related Stroke in Children With Congenital Heart Disease

Introduction: Stroke is an uncommon yet serious complication associated with cardiac catheterization in children with congenital heart disease. Our objective was to estimate the frequency and predictors of arterial ischemic stroke (AIS) in this specific setting. Methods: We performed a case-control study of children with congenital heart disease, who developed stroke in relation to cardiac catheterization performed at the Hospital for Sick Children between 1 January, 1992 and 1 January, 2014. Cases had new AIS (either symptomatic or silent) within 72 hours of cardiac catheterization and controls had cardiac catheterization but no new stroke within this time window. We estimated the frequency of AIS in children who underwent cardiac catheterization in this study period. Predictors of stroke that were tested include age, nature of intra-cardiac shunt, pre-procedural peripheral capillary oxygen saturation (SpO 2 ), type of catheterization (diagnostic versus interventional), duration of procedure, right versus left heart protocol, procedural anticoagulation and major/minor complications. Pediatric Stroke Outcome Measure was used to assess the neurological outcome of cases. Results: Twenty eight children (mean age1.66years; 64% males) developed stroke among 19414 children who underwent cardiac catheterization during the study period. The frequency of cardiac catheterization related-stroke in children is 1.44/1000 cardiac catheterizations. Univariate analysis revealed that younger age (OR 1.22; 95% CI (1.02,1.45); p=0.030), low SpO 2 pre-catheterization (OR 1.08; 95% CI (1.03,1.12); p=0.004), lack of procedural anticoagulation with heparin (OR 3.57; 95% CI (1.04,11.76); p=0.044), and minor complications during catheterization (OR 7.15; 95% CI (1.51,33.79); p=0.013) were associated with stroke. Low SpO 2 pre-catheterization and lack of procedural anticoagulation remained significant in multivariate analysis. Conclusion: The frequency of stroke after cardiac catheterization in children with congenital heart disease is 1.44/1000 cardiac catheterizations. Low SpO 2 pre-catheterization and lack of procedural anticoagulation appear to be associated with a higher risk of stroke.

Bivalirudin Is Associated With Improved In-Hospital Outcomes Compared With Heparin in Percutaneous Vascular Interventions: Observational, Propensity-Matched Analysis From the Premier Hospital Database.

Peripheral vascular interventions are increasingly preferred for the treatment of patients with symptomatic peripheral arterial disease because they are associated with similar clinical outcomes and lower morbidity than open surgical procedures. The objective of this study was to assess the comparative effectiveness of procedural anticoagulation with bivalirudin compared with unfractionated heparin in patients undergoing peripheral vascular interventions. This was a retrospective, observational study using the Premier Hospital administrative database. We examined 23,934 consecutive patients undergoing lower extremity peripheral vascular interventions between January 2008 and December 2012 who were treated with either bivalirudin or unfractionated heparin. In-hospital end points included death, myocardial infarction, transfusion, stroke, amputation, and the composite end points of major adverse cardiovascular events, and net adverse clinical events. Propensity score matching was performed to control for baseline imbalances and yielded 3649 matched pairs. After propensity score matching, patients treated with bivalirudin had lower in-hospital event rates with significantly lower mortality (odds ratio, 0.40; P=0.017), need for blood product transfusion (odds ratio, 0.74; P=0.009), major adverse cardiovascular events (odds ratio, 0.64; P=0.003), and net adverse clinical events (odds ratio, 0.72; P<0.001). These associations were observed consistently across clinically relevant subgroups. In patients undergoing peripheral vascular interventions, procedural anticoagulation with bivalirudin may result in more favorable in-hospital outcomes compared with unfractionated heparin, the current standard of care. These observations will require prospective confirmation in a randomized, controlled trial.

Heparin and anticoagulation.

Heparin, a sulfated polysaccharide, has been used as a clinical anticoagulant for over 90 years. Newer anticoagulants, introduced for certain specialized applications, have not significantly displaced heparin and newer heparin-based anticoagulants in most medical procedures. This chapter, while reviewing anticoagulation and these newer anticoagulants, focuses on heparin-based anticoagulants, including unfractionated heparin, low molecular weight heparins and ultra-low molecular weight heparins. Heparin's structures and its biological and therapeutic roles are discussed. Particular emphasis is placed on heparin's therapeutic application and its adverse effects. The future prospects are excellent for new heparins and new heparin-based therapeutics with improved properties.

Is perioperative bridging anticoagulation useful in patients with atrial fibrillation?

Temporary interruption of oral anticoagulation (OAC) for elective surgery or other elective invasive procedures is often required in patients with atrial fibrillation (AF) [1]. Several guidelines recommend stopping vitamin K antagonist (VKA) 5 days before procedures, and suggest bridging anticoagulation during VKA interruption in patients at high risk of thromboembolism [2, 3]. However, evidence on this issue is lacking, and guidelines recommendations regarding the need for bridging anticoagulation are based primarily on observational studies [1, 4]. Indeed, although heparin bridging therapy is commonly used in clinical practice, its efficacy and safety remain a controversial issue.

REAL-LIFE EXPERIENCE WITH A NEW ANTICOAGULATION REGIMEN FOR PATIENTS UNDERGOING LEFT-SIDED ABLATION PROCEDURES

Abstract Background Current guidelines for anticoagulation during left-sided procedures recommend the administration of unfractionated heparin (UFH) with an initial bolus of 50–100 U/kg, followed by continuous infusion to maintain an activated clotting time (ACT) ≥ 300 s. Our objective was to compare the effectiveness of this standard regimen (100 U/kg bolus) to a more aggressive approach (200 U/kg bolus). Methods We collected data on a series of consecutive patients undergoing left sided ablation procedures. Patients with an INR ≥2.0 on the day of the procedure were excluded. Procedural anticoagulation was performed using one of two UFH regimens: 1) 100 U/kg bolus, followed by 10 U/kg/hour infusion or 2) 200 U/kg bolus, followed by 20 U/kg/hour infusion. ACT was measured 10 min after the second bolus and then controlled every 20 min. Heparin was titrated throughout the procedure to maintain an ACT 300–400 s. Results 145 consecutive patients were included in the study: 34 received an initial bolus of 100 U/kg and 111 received 200 U/kg. The mean time required to reach an ACT ≥300 s was 15.25 min (95% CI 12.97–17.03) in the 200 U/kg group and 51.23 min (95% CI 40.65–61.81) in the 100 U/kg group (p Conclusion Current anticoagulation guidelines for left-sided ablation procedures almost universally fail to achieve an initial ACT ≥300 s. A 200 U/kg heparin bolus is much more effective to promptly reach the target ACT, with a low rate of overshoot.

Reversal of warfarin anticoagulation for urgent surgical procedures.

Patients treated with warfarin for therapeutic anticoagulation present a challenge for the perioperative management of urgent and emergent surgery. Anticoagulation must be reversed prior to most surgical procedures to prevent intraoperative bleeding. The purpose of this module is to review the options for urgent reversal of warfarin anticoagulation and the indications for each reversal agent. Selection of the appropriate agent is important to reduce unnecessary complications of treatment and to achieve optimal reversal of anticoagulation. When urgent surgery is required for patients taking warfarin, intravenous vitamin K1 should be used for procedures that can be delayed for six to 12hr. Vitamin K1 results in the activation of existing clotting factors rather than requiring the synthesis of new proteins, which allows for its relatively rapid onset of action. Intravenous vitamin K1 acts more quickly than oral administration, with reversal of anticoagulation occurring within six to 12hr vs 18-24hr, respectively. If surgery cannot be delayed, prothrombin complex concentrates (PCCs) should be given, and intravenous vitamin K1 should be infused concurrently to ensure sustained reversal of anticoagulation. The duration of action of both PCCs and plasma is six hours due to the short half-life of factor VII. Prothrombin complex concentrates contain small amounts of heparin and are contraindicated in patients with heparin-induced thrombocytopenia. Plasma should be used only if PCCs are unavailable or are contraindicated. Reversal of warfarin anticoagulation can be achieved in a safe and timely manner when the appropriate agent is selected and administered correctly.

Novel Oral Anticoagulants for DC Cardioversion Procedures: Utilization and Clinical Outcomes Compared with Warfarin

Novel oral anticoagulant (NOAC) agents dabigatran, rivaroxaban, and apixaban are increasingly utilized as thromboembolic prevention for patients with atrial fibrillation undergoing direct current cardioversion (DCCV) with post hoc analyses of clinical trials suggesting satisfactory safety and efficacy. This study characterizes utilization, effectiveness, and complications of NOAC agents for stroke prophylaxis in the setting of DCCV. Comparison of warfarin and NOAC agents as periprocedural anticoagulation for DCCV procedures performed at Cleveland Clinic from January 2009 through December 2013. Variables of interest include utilization rates for each NOAC agent stratified by clinical parameters including CHADS2 score, and associated clinical outcomes including cerebrovascular accident (CVA), transient ischemic attack (TIA), peripheral arterial embolism (PAE), and bleeding events during 8 weeks of postprocedure follow-up. Among 5,320 DCCV procedures, 673 (12.6%) cases were excluded due to inadequate follow-up. Warfarin was utilized in 3,721 (80.1%), dabigatran in 719 (15.5%), rivaroxaban in 159 (3.4%), and apixaban in 48 (1.0%) with a steady increase in NOAC utilization from 2011 to 2013. There were low rates of CVA/TIA (warfarin: 0.97% vs NOAC 1.62%, P = 0.162) and bleeding (warfarin: 1.02% vs NOAC: 0.5%, P = 0.247) and no significant differences detected between agents. Higher CHADS2 /CHA2 DS2 -VASC scores were associated with thromboembolic and bleeding risk. Increasing age, chronic kidney disease, diabetes, coronary disease, and deep vein thrombosis/pulmonary embolism were associated with increased bleeding risk. In a high-volume, single-center experience, NOAC utilization has grown to account for over a third of cardioversion procedures, and these agents appear safe and effective compared to warfarin with low rates of thromboembolic and bleeding complications.

Apixaban and oral implications.

Background Thrombotic disorders remain a leading cause of death in the Western world, and in this regard a number of anticoagulation treatment have been used, including heparins, fondaparinux, vitamin K antagonists (warfarin, acenocoumarol), and new oral anticoagulants such as apixaban. For years there has been great controversy regarding the use of anticoagulants in planning dental treatments that imply bleeding. The main concerns about using new oral anticoagulants in invasive dental procedures are bleeding due to the lack of an antidote, and the thrombotic risk of the disease for which anticoagulation was indicated in the first place. Material and Methods A literature search was conducted through May 2014 using the keyword “apixaban” for publications in the ISI Web of Knowledge. The search was extended to other databases (PubMed, Scopus and the Cochrane Library). Results Based on the results of the different studies, apixaban seems to be a good alternative to conventional anticoagulation and a reasonable treatment option, though its main and most common adverse effect is bleeding. Dose adjustment is needed in some patients, though regular laboratory monitoring is not required. The use of the drug in different patient populations will define its final indications and doses. Conclusions Regarding the use of apixaban in the dental setting, there is a compelling need for further clinical studies in order to establish more evidence-based guidelines for patients requiring antithrombotic treatment. Key words:Apixaban, dental treatment, dental implications.

Bivalirudin Versus Heparin With or Without Glycoprotein IIb/IIIa Inhibitors in Patients With STEMI Undergoing Primary Percutaneous Coronary Intervention

In the HORIZONS-AMI (Harmonizing Outcomes with RevasculariZatiON and Stents in Acute Myocardial Infarction) trial, 3,602 patients undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI) treated with bivalirudin had lower bleeding and mortality rates, but higher acute stent thrombosis rates compared with heparin+ a glycoprotein IIb/IIIa inhibitor (GPI). Subsequent changes in primary PCI, including the use of potent P2Y12 inhibitors, frequent radial intervention, and pre-hospital medication administration, were incorporated into the EUROMAX (European Ambulance Acute Coronary Syndrome Angiography) trial, which assigned 2,218 patients to bivalirudin versus heparin ± GPI before primary PCI. The goal of this study was to examine the outcomes of procedural anticoagulation with bivalirudin versus heparin ± GPI for primary PCI, given the evolution in primary PCI. Databases from HORIZONS-AMI and EUROMAX were pooled for patient-level analysis. The Breslow-Day test evaluated heterogeneity between trials. A total of 5,800 patients were randomized to bivalirudin (n= 2,889) or heparin ± GPI (n= 2,911). The radial approach was used in 21.3% of patients, prasugrel/ticagrelor was used in 18.1% of patients, and GPI was used in 84.8% of the control group. Bivalirudin compared with heparin ± GPI resulted in reduced 30-day rates of major bleeding (4.2% vs. 7.8%; relative risk [RR]: 0.53; 95% confidence interval [CI]: 0.43 to 0.66; p< 0.0001), thrombocytopenia (1.4% vs. 2.9%, RR: 0.48; 95% CI: 0.33 to 0.71; p= 0.0002), and cardiac mortality (2.0% vs. 2.9%; RR: 0.70; 95% CI: 0.50 to 0.97; p= 0.03), with nonsignificantly different rates of reinfarction, ischemia-driven revascularization, stroke, and all-cause mortality. Bivalirudin resulted in increased acute (<24 h) stent thrombosis rates (1.2% vs. 0.2%; RR: 6.04; 95% CI: 2.55 to 14.31; p< 0.0001), with nonsignificantly different rates of subacute stent thrombosis. Composite net adverse clinical events were lower with bivalirudin (8.8% vs. 11.9%; RR: 0.74; 95% CI: 0.63 to 0.86; p< 0.0001). There was no significant heterogeneity between the 2 trials for these outcomes, and results were consistent across major subgroups. Despite increased acute stent thrombosis, primary PCI with bivalirudin improved 30-day net clinical outcomes, with significant reductions in major bleeding, thrombocytopenia, and transfusions comparedwith heparin ± GPI, results that were consistent with evolution in PCI technique and pharmacotherapy. (Harmonizing Outcomes with RevasculariZatiON and Stents in Acute Myocardial Infarction [HORIZONS-AMI]; NCT00433966) (European Ambulance Acute Coronary Syndrome Angiography [EUROMAX]; NCT01087723).

Early Aortic Repair Worsens Concurrent Traumatic Brain Injury

Blunt thoracic aortic injury (BTAI) and traumatic brain injury (TBI) are the leading causes of death after blunt trauma, and TBI is common among patients with BTAI. Although aspects of aortic management, such as repair timing and procedural anticoagulation therapy, may complicate TBI, the optimal management of these patients is undefined. Adults with BTAI and moderate to severe TBI admitted to a level I trauma center over 12 years were retrospectively analyzed; patients presenting in extremis were excluded. The primary outcome was neurologic progression within 48 hours of aortic repair. Patients undergoing nonoperative aortic management served as controls for baseline TBI progression. Secondary outcomes were aortic morbidity and mortality and overall inpatient survival. Of 309 patients with BTAI, 138 had concurrent TBI, and 75 were included for analysis. Twenty-two (29%) were treated nonoperatively, 29 (39%) had early aortic repair (17 open, 12 endovascular), and 24 (32%) had delayed repair (3 open, 21 endovascular). The severity of TBI was similar between groups. Early aortic repair within 24 hours of admission was independently associated with worsening TBI, regardless of repair modality or anticoagulation use. In contrast, patients undergoing delayed repair had no perioperative neurologic progression despite procedural anticoagulation therapy. Early aortic repair was also associated with increased aortic morbidity and mortality. For patients with BTAI and TBI, early aortic intervention is associated with progressive TBI regardless of repair modality, as well as increased aortic morbidity and mortality. Patients not requiring emergent intervention can undergo delayed repair with full anticoagulation therapy.

A random forest based risk model for reliable and accurate prediction of receipt of transfusion in patients undergoing percutaneous coronary intervention.

BackgroundTransfusion is a common complication of Percutaneous Coronary Intervention (PCI) and is associated with adverse short and long term outcomes. There is no risk model for identifying patients most likely to receive transfusion after PCI. The objective of our study was to develop and validate a tool for predicting receipt of blood transfusion in patients undergoing contemporary PCI.MethodsRandom forest models were developed utilizing 45 pre-procedural clinical and laboratory variables to estimate the receipt of transfusion in patients undergoing PCI. The most influential variables were selected for inclusion in an abbreviated model. Model performance estimating transfusion was evaluated in an independent validation dataset using area under the ROC curve (AUC), with net reclassification improvement (NRI) used to compare full and reduced model prediction after grouping in low, intermediate, and high risk categories. The impact of procedural anticoagulation on observed versus predicted transfusion rates were assessed for the different risk categories.ResultsOur study cohort was comprised of 103,294 PCI procedures performed at 46 hospitals between July 2009 through December 2012 in Michigan of which 72,328 (70%) were randomly selected for training the models, and 30,966 (30%) for validation. The models demonstrated excellent calibration and discrimination (AUC: full model = 0.888 (95% CI 0.877–0.899), reduced model AUC = 0.880 (95% CI, 0.868–0.892), p for difference 0.003, NRI = 2.77%, p = 0.007). Procedural anticoagulation and radial access significantly influenced transfusion rates in the intermediate and high risk patients but no clinically relevant impact was noted in low risk patients, who made up 70% of the total cohort.ConclusionsThe risk of transfusion among patients undergoing PCI can be reliably calculated using a novel easy to use computational tool (https://bmc2.org/calculators/transfusion). This risk prediction algorithm may prove useful for both bed side clinical decision making and risk adjustment for assessment of quality.

EComment. Thrombus strikes back: Promising role of thromboelastography for thromboembolic risk prediction in HeartMate II recipients

Heart failure is a major public health problem representing the ultimate stage of various cardiovascular diseases. Currently left ventricular assist devices (LVADs) have been increasingly used for the management of patients with end-stage heart failure. Every year approximately 4000 LVADs are implanted in the US; approximately three-quarters of these are HeartMate II. The HeartMate II is a small, continuous flow, rotary, left-sided heart pump approved by the FDA for bridge to transplantation in cardiac transplant candidates with the advantages of smaller size, less invasive surgical implantation procedure and low dose anticoagulation requirement. However, according to a recently published paper based on pooled data from 895 patients with the HeartMate II LVAD device, the thrombosis rate occurring early after implantation is nearly four times higher than rates seen in pre-approval clinical trials [1]. Karimi et al. reported that thrombelastography (TEG) guided antiplatelet therapy reduces the late onset bleeding rate in HeartMate II recipients [2]. Thrombelastography is a superb coagulation test which has the advantage of combining multiple data obtained from various coagulation tests into a single read-out. Furthermore, TEG gives information about platelet function, clot strength, and fibrinolysis which other coagulation tests cannot provide. Prompted by the manuscript of Karimi et al, we speculate that TEG could be a useful test for predicting thrombotic risk in HeartMate II recipients. Haemostasis occurs with orchestrated function of platelets, clotting factors and vascular endothelium. Thrombelastography provides an effective and convenient means of monitoring the entire coagulation cascade which can traditionally be measured via several conventional tests. Thrombelastography is a promising test for predicting thrombosis [3]. It demonstrates a hypercoagulable state that is not detected by prothrombin time or partial thromboplastin time. Conventional coagulation tests cannot assess factors predicting thromboembolic risk such as clot strength and degree of clot dissolution [4]. In summary, HeartMate II recipients have surprisingly high device thrombosis rates. Since these patients are also at risk for bleeding complications, anticoagulation should be carefully titrated. The art of LVAD-implanted patient management is weighing the risk between haemorrhagic and thromboembolic events. Thrombelastography may guide clinicians while making challenging decisions. Conflict of interest: none declared

Peribulbar anesthesia in 750 patients treated with oral anticoagulants.

To check the safety of continuation of oral anticoagulants in ophthalmic procedures requiring a peribulbar anesthesia. A prospective case control study included 750 patients with oral anticoagulants in group A and 750 patients who had never been treated with oral anticoagulant in group B. Hemorrhages were graded as follows: 1) spot ecchymosis of eyelid and or subconjunctival hemorrhage; 2) eyelid ecchymosis involving half of the lid surface area; 3) eyelid ecchymosis all around the eye, no increase in intraocular pressure; 4) retrobulbar hemorrhage with increased intraocular pressure. In group A, grade 1 was observed in 13 patients (1.74%) and grade 2 in 2 patients (0.26%). In group B, grade 1 was observed in 12 patients (1.6%) and grade 2 was absent. No 3 or 4 hemorrhage grade was encountered in both groups. There was not significant difference in grade 1 hemorrhage between both groups (P=0.21). Oral anticoagulants were not associated with a significant increase in potentially sight-threatening local anesthetic complications.

Evaluation of Pharmacist-Managed Dabigatran in an Inpatient Setting

Although therapeutic drug monitoring is not required for patients receiving dabigatran to determine therapeutic efficacy, there are a number of other factors to consider. Currently, there are no studies evaluating pharmacist-led management of dabigatran. The role of inpatient pharmacists related to the management of dabigatran was evaluated. All adult patients who received at least 1 dose of dabigatran with a length of stay greater than 24 hours in a single-center, community hospital between May 2011 and August 2012 were retrospectively reviewed (n = 176). Almost half of the patients (46%) required pharmacist intervention related to dabigatran management during hospital admission. Of patients receiving dabigatran prior to hospital admission, 18.4% were admitted on an inappropriate home dose. Transitioning between dabigatran and alternative anticoagulants accounted for the majority of pharmacist interventions (74.2%), with patients transitioning from unfractionated heparin to dabigatran occurring most frequently. Renal impairment requiring dose adjustment or drug discontinuation occurred in 6.3% of patients, whereas 6.8% of patients required pharmacist intervention for procedural anticoagulation. Inpatient therapy was determined to be relatively safe, with few patients (1.7%) requiring permanent discontinuation of dabigatran as a result of a bleeding complication. Pharmacists significantly contributed to the safe and appropriate use of dabigatran during hospitalization.