Periprocedural Anticoagulation Management Research Articles

Peri-procedural management of anti-platelets and anticoagulation in patients undergoing MitraClip procedure.

The MitraClip device was recently approved by the FDA for the management of severe degenerative mitral regurgitation in patients considered to be high risk for surgical repair or replacement of the mitral valve. The management of anti-platelet and anticoagulant therapy before, during, and after the MitraClip placement is not well defined given the lack of evidence from large randomized trials. In this paper, we propose practical management guidelines for using these agents.

Does periprocedural anticoagulation management of atrial fibrillation affect the prevalence of silent thromboembolic lesion detected by diffusion cerebral magnetic resonance imaging in patients undergoing radiofrequency atrial fibrillation ablation with open irrigated catheters? Results from a prospective multicenter study

Silent cerebral ischemia (SCI) has been reported in 14% of cases after catheter ablation of atrial fibrillation (AF) with radiofrequency (RF) energy and discontinuation of warfarin before AF ablation procedures. The purpose of this study was to determine whether periprocedural anticoagulation management affects the incidence of SCI after RF ablation using an open irrigated catheter. Consecutive patients undergoing RF ablation for AF without warfarin discontinuation and receiving heparin bolus before transseptal catheterization (group I, n = 146) were compared with a group of patients who had protocol deviation in terms of maintaining the therapeutic preprocedural international normalized ratio (patients with subtherapeutic INR) and/or failure to receive pretransseptal heparin bolus infusion and/or ≥2 consecutive ACT measurements <300 seconds (noncompliant population, group II, n = 134) and with a group of patients undergoing RF ablation with warfarin discontinuation bridged with low molecular weight heparin (group III, n = 148). All patients underwent preablation and postablation (within 48 hours) diffusion magnetic resonance imaging. SCI was detected in 2% of patients (3/146) in group I, 7% (10/134) in group II, and 14% (21/148) in group III (P <.001). "Therapeutic INR" was strongly associated with a lower prevalence of postprocedural silent cerebral ischemia (SCI). Multivariable analysis demonstrated nonparoxysmal AF (odds ratio 3.8, 95% confidence interval 1.5-9.7, P = .005) and noncompliance to protocol (odds ratio 2.8, 95% confidence interval 1.5-5.1, P <.001] to be significant predictors of ischemic events. Strict adherence to an anticoagulation protocol significantly reduces the prevalence of SCI after catheter ablation of AF with RF energy.

Assessment of the Outcomes Associated with Periprocedural Anticoagulation Management in Children with Acute Lymphoblastic Leukemia

To report the outcomes of an institutional protocol for periprocedural anticoagulant (AC) management in children with acute lymphoblastic leukemia (ALL). Children being treated for ALL who received full-dose (therapeutic) anticoagulation before undergoing at least 1 lumbar puncture (LP) were included in this retrospective cohort study. The main outcome was the risk of traumatic LP; exploratory analysis included the risks of symptomatic spinal hematoma and progression/recurrence of the thrombotic event. Analyses were conducted using logistic regression analysis with a generalized estimating equation approach. Twenty-two children with ALL receiving an AC underwent a total of 396 LPs. Although traumatic LP was associated with full-dose AC therapy in univariable analysis, a multiple logistic regression model controlling for other risk factors for traumatic LP showed that AC therapy was not significantly associated with the risk of traumatic LP when the ACs were held as per the institutional protocol. No patient developed symptomatic spinal hematoma. Exploratory analysis revealed that AC dose, a likely marker of thrombus burden, was significantly associated with progression/recurrence of the thrombotic event in univariable analysis. In our cohort, recent AC therapy was not statistically associated with an increased risk of bleeding after LP when following a specific protocol for periprocedural AC management. The risk associated with the progression/recurrence of thromboembolic events requires further evaluation.

Outcomes and total costs of outpatient vs. inpatient peri-procedural anticoagulation management of mechanical prosthetic heart valve patients

Background/objectivesThe most cost-effective periprocedural management of patients with mechanical heart valves (MHV) is uncertain. The objective was to compare the effectiveness, safety and costs for inpatient intravenous unfractionated heparin (IVUH) vs. outpatient low molecular weight heparin (LMWH) “bridging” as periprocedural anticoagulation management for MHV patients. MethodsIn a case-cohort study, Olmsted County, MN residents with MHV who received outpatient periprocedural LMWH management (cases) over the 11-year period, 1997–2007, were matched to residents with MHV who received inpatient IVUH periprocedural management on valve location and type, and on procedure type. Patients were followed for 3months following hospitalization to identify thromboembolism (TE) and major bleeding. Total costs from 30days before to 90days after the procedure were determined from the Olmsted County Healthcare Expenditure and Utilization Database. Outcomes were compared using survival analysis and costs were compared using the Wilcoxon rank sum. Results149 cases (100 aortic, 29 mitral, 20 both; 64% bileaflet) were compared to 149 cohort members (100 aortic, 29 mitral, 20 both; 75% bileaflet). While the 3-month cumulative incidence of TE did not differ significantly among cases (2.7%) and cohort members (4.7%; p=0.36), major bleeding was significantly lower in cases (5.4% vs. 15.4%; p<0.005). Total costs were significantly higher for cohort members ($50,984 vs. $39,347; p=0.002) due to higher inpatient costs ($47,729 vs. $34,860; p=0.0002). ConclusionsOutpatient bridging LMWH therapy is equally effective, but safer and less costly than inpatient IVUH as periprocedural anticoagulation management for MHV patients.

Safety of pacemaker and implantable cardioverter–defibrillator implantation during uninterrupted warfarin treatment — The FinPAC study

Periprocedural management of oral anticoagulation (OAC) in patients undergoing cardiac rhythm management (CRM) device implantation is controversial. Prior studies demonstrate that uninterrupted OAC may be safe, but limited data from randomized trials exist. We conducted a multicenter, randomized trial to evaluate the safety of uninterrupted OAC during CRM device implantation. Patients on long-term warfarin (N=213) treatment with contemporary indication for CRM device implantation were randomized to uninterrupted versus interrupted (2 days) OAC therapy. The primary outcome included major bleeding events necessitating additional intervention and thromboembolic events during 4 weeks follow-up. The randomized groups were well matched in terms of bleeding and thromboembolic risk. Only one (1%) patient in the uninterrupted OAC group (N=106) needed blood transfusion due to rupture of proximal cephalic vein. Large hematomas were detected in 6% of patients in both groups, but there was no need for pocket revision in either group. Any pocket hematoma was observed in 35 patients (33%) in the uninterrupted OAC group and in 43 patients (40%) with interrupted OAC and uninterrupted OAC strategy was non-inferior to interrupted OAC (HR 0.86, 95%, p=0.001 for non-inferiority). One patient with interrupted OAC had stroke 3 days after the procedure. Hospital stay was comparable in all patient groups. Our randomized study demonstrates that CRM devices can be safely implanted without discontinuation of warfarin treatment.

Catheter Ablation of Atrial Fibrillation without Coumadin Discontinuation, Protects against Thromboembolic Complications

Evidence From the Role of Coumadin in Preventing Thromboembolism in Atrial Fibrillation (AF) Patients Undergoing Catheter Ablation trial [COMPARE; NCT01006876] confirms that the continuous use of warfarin while performing catheter ablation of AF significantly reduces the occurrence of periprocedural stroke/transient ischemic attack and bleeding complications [Di Biase L et al. Heart Rhythm 2013]. The results suggest that periprocedural anticoagulation management could play an important role in the occurrence of these complications.

Collateral Damage from Catheter Ablation of Atrial Fibrillation Lessons Learnt in the Past Decade.

Catheter ablation for atrial fibrillation (AF) has been increasingly performed over the past decade. Regardless of technological advances and technique improvement, catheter ablation for AF remains a highly complex procedure and the risk of procedural complications is not negligible. This article discusses the management and the approach to avoid the serious complications of catheter AF ablation including pulmonary vein stenosis, atrioesophageal fistula, cardiac tamponade, stroke and collateral nervous damage. The management of periprocedural anticoagulation and the complications associated with epicardial AF ablation are also described.

Thrombophilia Effect On Periprocedural Thromboembolism and Bleeding in Chronically Anticoagulated Patients

AbstractAbstract 3404 Background:Appropriate periprocedural management of the chronically-anticoagulated patient with an inherited or acquired thrombophilia is uncertain. Objective:To estimate the 3-month cumulative incidence of thromboembolism (TE) and major bleeding and test thrombophilia as a potential predictor of these outcomes among chronically-anticoagulated patients undergoing a procedure. Methods:2182 consecutive patients referred to the Mayo Thrombophilia Center for standardized peri-procedural anticoagulation management were followed for TE, major bleeding and survival. The three-month cumulative incidence rates for TE, major bleeding and death were estimated by Kaplan-Meier analyses. For each chronic anticoagulation indication, we tested “strong” thrombophilia (antithrombin, protein C or protein S deficiency, homozygous or combined heterozygous Factor V Leiden or prothrombin G20210A), ”weak” thrombophilia (heterozygous Factor V Leiden or prothrombin G20210A), lupus anticoagulant/antiphospholipid antibodies and bridging heparin as potential predictors of TE and major bleeding using Cox proportional hazards modeling. Results:Patients with thrombophilia tended to be younger with a slight female predominance. Compared to no thrombophilia, thrombophilia patients (n=202; 143 bridged with heparin) had similar rates of venous (0% vs. 0.5%; p=0.34) and arterial (0.5% vs. 0.5%; p=0.94) thromboembolism, major bleeding (2.0% vs. 2.0%; p=0.97) and mortality (1.5% vs. 2.2%; p=0.52). Among thrombophilia patients, the TE and major bleeding rates were similar for strong (n=29) or weak thrombophilia (n=99), or lupus anticoagulant/antiphospholipid antibodies (n=74). Similarly, among thrombophilia patients, bridging heparin did not affect the rates of major bleeding (2.1% vs. 1.7%; p=0.85) or TE (0.7% vs. 0%, p=0.52). Conclusions:Inherited or acquired thrombophilia does not appear to impact the rates of TE, major bleeding or mortality after temporary interruption of chronic anticoagulation for an invasive procedure. Disclosures:No relevant conflicts of interest to declare.

How I treat anticoagulated patients undergoing an elective procedure or surgery

AbstractThe periprocedural management of patients receiving long-term oral anticoagulant therapy remains a common but difficult clinical problem, with a lack of high-quality evidence to inform best practices. It is a patient's thromboembolic risk that drives the need for an aggressive periprocedural strategy, including the use of heparin bridging therapy, to minimize time off anticoagulant therapy, while the procedural bleed risk determines how and when postprocedural anticoagulant therapy should be resumed. Warfarin should be continued in patients undergoing selected minor procedures, whereas in major procedures that necessitate warfarin interruption, heparin bridging therapy should be considered in patients at high thromboembolic risk and in a minority of patients at moderate risk. Periprocedural data with the novel oral anticoagulants, such as dabigatran, rivaroxaban, and apixaban, are emerging, but their relatively short half-life, rapid onset of action, and predictable pharmacokinetics should simplify periprocedural use. This review aims to provide a practical, clinician-focused approach to periprocedural anticoagulant management.

Periprocedural Anticoagulant Management

Approximately 6 million Americans are treated with chronic anticoagulation. Of these, 10% of patients will require temporary anticoagulation interruption for an invasive procedure each year. Anticoagulation management during this period requires a formal strategy in order to limit both bleeding and thromboembolic complications. This article will give health care providers a stepwise approach to this process. The first step is to determine whether warfarin discontinuation is necessary for the planned procedure. For procedures requiring warfarin discontinuation, the second step is to determine the appropriate timing. The third step is to identify the patient-specific thromboembolic risk in order to determine which patients require bridging therapy with parenteral anticoagulants. The fourth step is both the most complicated and most critical step in this management strategy. This decision-making step involves choosing the appropriate anticoagulant regimen, dose, and timing of reinitiation that is best tailored to a specific patient, as well as determining procedural variables, in order to limit bleeding and thrombotic complications.

Three-month cumulative incidence of thromboembolism and bleeding after periprocedural anticoagulation management of arterial vascular bypass patients

The objective of this study was to determine 3-month cumulative incidence of peri-procedural thromboembolism (TE) including graft occlusion, and peri-procedural bleeding for chronically anticoagulated vascular bypass graft (BG) patients requiring temporary warfarin interruption for an invasive procedure. Appropriate peri-procedural management of patients receiving chronic warfarin therapy to preserve lower extremity arterial BG patency is unknown. In a protocol driven, cohort study design, all BG patients referred to the Mayo Clinic Thrombophilia Center for peri-procedural anticoagulation (1997-2007) were followed forward in time to estimate the 3-month cumulative incidence of TE and bleeding. Decisions to provide "bridging" low molecular weight heparin (LMWH) were individualized based on estimated risk of TE and bleeding. There were 78 BG patients (69 ± 10 years; 38% women), of whom 73% had a distal autogenous and 53% had prosthetic BG; 45% received antiplatelet therapy. Peri-procedural LMWH was prescribed for 77% of patients and did not vary by BG distal anastomosis location or type. The 3-month cumulative incidence of TE was 5.1% (95% CI 1.4-12.6), including two BG occlusions, one DVT, and one myocardial infarction. Major bleeding occurred in 1 patient (1.28%, 95% CI 0.0-6.94). One patient died due to heart failure. TE and bleeding did not differ by bridging status. The 3-month cumulative incidence of TE among BG patients in whom warfarin is temporarily interrupted for an invasive procedure may be higher than in other "bridging" populations (atrial fibrillation, prosthetic heart valve, venous thromboembolism). This finding underscores the often tenuous nature of distal bypass grafts necessitating an aggressive approach to peri-procedural anticoagulation management.

Anticoagulation Management Pre- and Post Atrial Fibrillation Ablation: A Survey of Canadian Centres

Anticoagulation in patients undergoing atrial fibrillation (AF) ablation is crucial to minimize the risk of thromboembolic complications. There are broad ranges of approaches to anticoagulation management pre and post AF ablation procedures. The purpose of this study was to determine the anticoagulation strategies currently in use in patients peri- and post AF ablation in Canada. A Web-based national survey of electrophysiologists performing AF ablation in Canada collected data regarding anticoagulation practice prior to ablation, periprocedural bridging, and duration of postablation anticoagulation. The survey was completed by 36 (97%) of the 37 electrophysiologists performing AF ablation across Canada. Prior to AF ablation, 58% of electrophysiologists started anticoagulation for patients with paroxysmal AF CHADS(2) scores of 0 to 1, 92% for paroxysmal AF CHADS(2) scores ≥ 2, 83% for persistent AF CHADS(2) scores of 0 to 1, and 97% for persistent AF CHADS(2) scores ≥ 2. For patients with CHADS(2) 0 to 1, warfarin was continued for at least 3 months by most physicians (89% for paroxysmal and 94% for persistent AF). For patients with CHADS(2) ≥ 2 and with no recurrence of AF at 1 year post ablation, 89% of physicians continued warfarin. Although guidelines recommend long-term anticoagulation in patients with CHADS(2) ≥ 2, 11% of physicians would discontinue warfarin in patients with no evidence of recurrent AF 1 year post successful ablation. Significant heterogeneity exists regarding periprocedural anticoagulation management in clinical practice. Clinical trial evidence is required to guide optimal periprocedural anticoagulation and therapeutic decisions regarding long-term anticoagulation after an apparently successful catheter ablation for AF.

Predictors of major bleeding in peri‐procedural anticoagulation management

Appropriate periprocedural management for chronically anticoagulated patients requires assessment of patient-specific thrombosis and bleeding risks. However, predictors of post-procedure bleeding are unknown. To determine the 3-month cumulative incidence and independent predictors of peri-procedural bleeding in chronically anticoagulated patients requiring temporary warfarin interruption for an invasive procedure. In a protocol driven, cohort study design, all patients referred to the Mayo Clinic Thrombophilia Center for peri-procedural anticoagulation management (1997-2007; n = 2182), were followed forward in time to determine the 3-month cumulative incidence of peri-procedural bleeding (Kaplan-Meier product limit) and potential predictors of bleeding (Cox proportional hazards). Decisions to 'bridge' with low-molecular-weight heparin were based on estimated thromboembolism and bleeding risk. Indications for chronic anticoagulation included venous thromboembolism (38%), atrial fibrillation (30%) and mechanical heart valves (27%). Of these, 1496 (69%) patients received bridging therapy. The 3-month cumulative incidence rates of major and overall bleeding were 2.1% and 5.1%, respectively. Major bleeding occurred more frequently in patients receiving bridging therapy (3% vs. 1%; P = 0.017). Independent predictors (hazard ratio; 95% confidence interval) of major bleeding included mitral mechanical heart valve (2.2; 1.1-4.3), active cancer (1.8; 1.0-3.1), prior bleeding history (2.6; 1.5-4.5) and re-initiation of heparin therapy within 24 h after the procedure (1.9; 1.1-3.4). Factors predisposing to peri-procedural bleeding are primarily patient-specific. Premature heparin re-initiation is an avoidable provider-specific variable to consider.

Conservative Peri-Procedural Anticoagulation Management in Patients with Venous Thromboembolic Disease Results in a Low Proportion of Thrombosis and Bleeding

Abstract 546The optimal strategy for peri-procedural warfarin management in patients with venous thromboembolic disease (VTE) is unknown because most studies to date have included small proportions of VTE patients. Guidelines are largely based on expert opinion and recommend low-molecular-weight heparin (LMWH) bridging in patients at high or moderate risk for VTE. LMWH bridging may be associated with an increased bleeding risk, which if occurs, would result in temporary cessation of anticoagulation (AC) potentially leading to a paradoxical increased thrombotic risk. We conducted a single-center retrospective cohort study to examine the effectiveness of conservative peri-procedural AC management in VTE (DVT or PE) patients.We included all patients from our institution’s thrombosis unit between 1993 and 2011 who required peri-procedural AC management for planned procedures. The thrombosis unit has, on average, 800 patients on chronic AC for VTE. Patients were excluded if they had other indications for AC, had an acute VTE <90 days before the procedure, or had no follow-up after the procedure. Our centre uses a conservative bridging strategy in these patients consisting of holding warfarin 5 days before the procedure without administering LMWH. Postoperatively all patients resume warfarin as soon as they can swallow. For ambulatory procedures no LMWH is given after the procedure, whereas patients undergoing in-hospital procedures are usually given prophylactic LMWH starting the morning after surgery until discharge or when the INR is therapeutic, whichever occurs first. The primary outcome was incidence of VTE within 90 days of the procedure. Secondary outcomes were 90-day incidence of major and total bleeding and all-cause mortality. Confidence intervals for proportions were calculated using the Wilson’s score method. Groups were compared using χ2 or Fisher’s exact tests. Survival analysis was done using the Kaplan-Meier method. Two-sided p values ≤0.05 were considered statistically significant.During the study period there were 634 procedures in 416 patients (47.4% males). The mean age was 64.9 years (SD 15.8) and 79.1% of patients had idiopathic VTE. There were 156 procedures (24.6%) completed in-hospital. Pre- and post-procedure bridging was used in 15 (2.4%) and 153 (24.1%) procedures, respectively. The 90-day cumulative incidence of VTE was 0.63% (95% CI 0.25–1.61). The VTE events were 4 DVTs (postoperative day 3, 29, 41, 43) with no associated mortality. The 90-day cumulative incidence of major and total bleeding events was 1.58% (95% CI 0.86–2.88) and 3.47% (95% CI 2.30–5.20), respectively. All-cause mortality rate was 0.63% (95% CI 0.25–1.61); one patient died from a myocardial infarction 3 days after an abdominal aortic aneurysm repair, a second died from an ischemic stroke the morning of a colonoscopy and 2 patients had non-VTE related deaths.The effects of type of procedure and use of bridging on outcomes are shown in Table 1. The use of pre- or post-procedure bridging was not associated with VTE or bleeding. There were significantly more total bleeding events with inpatient procedures. There was a significant correlation between bleeding and VTE events: 13.6% of patients with any bleeding and 30% with major bleeding developed a VTE complication compared with 0.2% of those without bleeding. Spearman’s correlation coefficients were 0.311 and 0.470, respectively (p<0.001). Two postoperative DVTs (50%) developed after warfarin was held for an extended period of time (1 major bleed, 1 neurosurgical complication).Conservative peri-procedural AC management in VTE patients on warfarin for at least 3 months results in a low risk of thrombotic and bleeding events. A randomized controlled trial in chronically anticoagulated VTE patients is needed to provide definitive conclusions but a conservative approach appears promising.Effect of Type of Procedure and Bridging on OutcomeOutcomeVTE N (%)No (N=630)Yes (N=4)PInpatient procedure154 (24.4%)2 (50%)0.255Pre-procedure bridging15 (2.4)0 (0)1Post-procedure bridging151 (24)2 (50)0.247Total Bleeding N (%)No (N=612)Yes (N=22)Inpatient procedure146 (23.9)10 (45.5)0.039Pre-procedure bridging15 (2.5)0 (0)1Post-procedure bridging147 (24)6 (27.3)0.800Major bleeding N (%)No (N=624)Yes (N=10)Inpatient procedure153 (24.5)3 (30)0.714Pre-procedure bridging15 (2.4)0 (0)1Post-procedure bridging151 (24.2)2 (20)1 Disclosures:Lazo-Langner:Pfizer Inc.: Honoraria; Leo Pharma: Honoraria.

Periprocedural Anticoagulation Management of Patients With Venous Thromboembolism

Patients with venous thromboembolism (VTE) often require temporary warfarin interruption for an invasive procedure. The incidence of thromboembolism and bleeding related to periprocedural anticoagulation management of such patients is unknown. In a protocol-driven, inception cohort design study, all VTE patients (n=775) referred for periprocedural anticoagulation management (1997-2007) were followed-up to estimate the 3-month cumulative incidence of thromboembolism and bleeding. Patients were stratified by thrombus acuity (acute, <30 days; subacute, 31-90 days; or chronic > or =91 days). Decisions to provide "bridging" low-molecular-weight heparin were based on estimated thromboembolism and bleeding risk. Low-molecular-weight heparin was more often administered in acute (87%) and subacute (81%) VTE compared to chronic VTE (59%; P<0.001). The 3-month cumulative incidence of thromboembolism (1.8%), major hemorrhage (1.8%), and mortality (1.7%) were low and did not differ by management strategy. Active cancer was the only independent predictor of thrombotic recurrence (HR, 4.86; 95% CI, 1.6-14.5; P=0.005), major hemorrhage (HR, 6.8; 95% CI, 2.1-21.7; P=0.001), and death (HR, 32.7; 95% CI, 4.3-251.2; P=0.0008). Thromboembolism, bleeding, and death among VTE patients in whom anticoagulation is temporarily interrupted for an invasive procedure is low. Cancer patients require particular care given their propensity for both clotting and bleeding.

Perioperative Management of Anticoagulation during Device Implantation-The UK Perspective

Increasing numbers of patients taking oral anticoagulation are presenting for device implantation. Cessation of anticoagulation in the perioperative period may expose patients to increased risk of thromboembolic events, while continuing anticoagulation may increase the risk of bleeding. There are few guidelines or randomized controlled trials to guide perioperative management. We carried out a questionnaire-based study of all cardiologists implanting devices in the United Kingdom to establish if there was consensus on management of anticoagulation in patients undergoing pacemaker implantation. There is significant variation in management of these patients. Eighty-nine percent of doctors stop oral anticoagulation a mean 3.7 days prior to pacemaker implantation in patients with a mechanical mitral valve, with 94% using heparin to provide preoperative anticoagulation: 58% unfractionated heparin, 40% low molecular weight heparin. The maximum accepted international normalized ratio for implantation ranged from 1.4 to 3 (median 1.8). Postoperatively, 86% restart heparin after a mean 8.5 hours. Only 11% continue oral anticoagulation throughout the implantation period. There is a hierarchy of perceived embolic risk with doctors using progressively less anticoagulation in patients with prosthetic aortic valve, high-risk, and low-risk atrial fibrillation. In contrast, only 7% of implanters stop theinopyridines prior to device implantation in patients with a 2-month-old drug eluting stent. Perioperative anticoagulation management of patients undergoing device procedures is currently performed with little consensus. This emphasizes the need for careful national and international audit of periprocedural anticoagulation management and its associated complications with a view to developing international consensus guidelines. (PACE 2010; 389-393).

Three-Month Cumulative Incidence of Thromboembolism and Bleeding After Periprocedural Anticoagulation Management of Patients with Active Cancer.

Abstract 491 Introduction:Chronically-anticoagulated patients with active cancer (Ca) often require temporary interruption of warfarin for an invasive diagnostic or therapeutic procedure. While such patients may be at increased risk for periprocedural thromboembolism and bleeding, there are virtually no estimates of these outcomes among Ca patients or the most appropriate periprocedural anticoagulation management. The aims of this study were to estimate rates of these outcomes among Ca patients and to test active cancer and “bridging” low molecular weight heparin (LMWH) as potential predictors of these outcomes. Patients and Methods:In a retrospective cohort study, all chronically-anticoagulated patients referred to the Mayo Clinic Thrombophilia Center for periprocedural anticoagulation management over the 11-year period, 1997-2007, were followed forward in time for the outcomes of venous and arterial thromboembolism (VTE; ATE), major bleeding and vital status within 3 months of consultation. Warfarin was stopped 4-5 days prior to the procedure and patients received bridging LMWH according to the estimated risk of thromboembolism and bleeding. All outcome events were centrally adjudicated using pre specified criteria. Results:The total cohort (n=2517) included 500 patients with Ca. Chronic anticoagulation indications included prior VTE (n=1033), mechanical heart valve (n=669), atrial fibrillation (n=530) and other (mainly vascular bypass; n=285). 65% and 64% of patients with and without Ca received bridging LMWH, respectively. Prior VTE was more common among Ca patients compared to those without CA, both in the bridged (56% vs 37%; p<0.001) and the non-bridged (48% vs 39%; p<0.05) groups. The 3 month rate for the composite of VTE, ATE or bleeding was higher among Ca patients compared to patients without Ca (5% vs 2%; p=0.004) due to higher post procedure rates of VTE (1% vs 0.2%; p<0.001) and major bleeding (4% vs 1.7%; p=0.009); the post procedure ATE rates were low in both groups (0.40% vs 0.45%). For the entire cohort, patients receiving bridging LMWH had a significantly higher rate of post procedure bleeding (5% vs 1%; p<0.05). Finally, there were significantly more deaths in Ca patients compared to non-Ca patients (5% vs. 1%; p<0.001). Conclusions:The three-month rates of VTE, major bleeding and death among patients with Ca in whom anticoagulation is temporarily interrupted for an invasive procedure is significantly higher than in patients without Ca, especially the major bleeding rate. Use of heparin increases this rate even farther, suggesting that bridging should be used with caution in patients with active cancer. Disclosures:No relevant conflicts of interest to declare.

Periprocedural management of anticoagulation and antiplatelet therapies in patients undergoing electrophysiologic procedures

Electrophysiologic studies, radiofrequency ablation, and device implantations including pacemakers and defibrillators have become essential tools in the armamentarium of electrophysiologists. These procedures are being performed in patients with complex comorbidities, many of whom chronically take anticoagulation or antiplatelet agents. Careful management of anticoagulation before, during, and after electrophysiologic procedures including device implantations is critical to minimize bleeding and thrombotic complications and to optimize patient outcomes.

Peri-procedural anticoagulation management of mechanical prosthetic heart valve patients

Introduction To estimate the three-month cumulative incidence of thromboembolism and bleeding among mechanical heart valve (MHV) patients receiving peri-procedural anticoagulation management, consecutive MHV patients referred to the Mayo Clinic Thrombophilia Center for peri-procedural anticoagulation management over the seven-year period, 1997-2003, were followed for three months for thromboembolism, bleeding and vital status. Materials and Methods Warfarin was stopped 4-5 days prior to the procedure, and re-started after the procedure as soon as hemostasis was assured. The decision to provide bridging therapy with low molecular weight (LMWH) or unfractionated (UFH) heparin was individualized and based on the estimated risks of TE and bleeding. Results 556 MHV patients (372 aortic only, 136 mitral only, 48 with multiple valves) underwent 580 procedures. The three-month cumulative incidence of thromboembolism was 0.9% which included: cerebral ischemia (n = 3), unstable angina (n = 1), acute myocardial infarction (n = 1). None were fatal. The cumulative incidence of major bleeding was 3.6% and fatal in 0.2%. The incidence of major bleeding events did not differ by postoperative anticoagulant strategy whether LMWH (3.7%), UFH (6.1%), or no heparin (2.4%) was used (p = 0.26). Conclusions The three-month cumulative incidence of thromboembolism among MHV patients in whom anticoagulation is temporarily interrupted for an invasive procedure is low. Whereas bleeding exceeds thromboembolic complications, our current practice is to restart warfarin as soon as possible post-procedure. Post-procedural heparin use is reserved for patients with the highest thromboembolic risk (mitral MHV, multiple MHVs, MHV with prior stroke or atrial fibrillation) waiting at least 48 hours before initiating.

Periprocedural Anticoagulation Management of Patients With Nonvalvular Atrial Fibrillation

To estimate the 3-month cumulative incidence of thromboembolism (TE), bleeding, and death among consecutive patients with nonvalvular atrial fibrillation (AF) who were receiving long-term anticoagulation therapy and were referred to the Thrombophilia Center at Mayo Clinic for periprocedural anticoagulation management. In a prospective cohort study of consecutive patients receiving long-term anticoagulation therapy who were referred to the Thrombophilia Center for periprocedural anticoagulation management over the 7-year period, January 1, 1997, to December 31, 2003, 345 patients with nonvalvular AF were eligible for inclusion. Warfarin was stopped 4 to 5 days before and was restarted after surgery as soon as hemostasis was assured. The decision to provide bridging therapy with heparin was individualized and based on the estimated risks of TE and bleeding. The 345 patients with AF (mean +/- SD age, 74+/-9 years; 33% women) underwent 386 procedures. Warfarin administration was not interrupted for 44 procedures. Periprocedural heparin was provided for 204 procedures. Patients receiving heparin were more likely to have prior TE (43% vs 24%; P<.001) and a higher CHADS2 (congestive heart failure, hypertension, age, diabetes, stroke) score (2.2 vs 1.9; P=.06). Four patients had 6 episodes of TE (3 strokes and 3 acute coronary episodes; TE rate, 1.1%; 95% confidence interval, 0.0%-2.1%). Nine patients had 10 major bleeding events (major bleeding rate, 2.7%; 95% confidence interval, 1.0%-4.4%). There were no deaths. Neither bleeding nor TE rates differed by anticoagulant management strategy. The 3-month cumulative incidence of TE and bleeding among patients with AF in whom anticoagulation was temporarily interrupted for an invasive procedure was low and was not significantly influenced by bridging therapy.