Chronic Anticoagulation Therapy Research Articles

Novi oralni antikoagulantni lekovi - uticaj mehanizma delovanja na efikasnost i bezbednost

Administration of oral anticoagulant therapy is a mainstay of the prevention of AF -related thromboembolism. Until recently, the only available option for chronic oral anticoagulation therapy was the administration of vitamin K antagonists, however treatment with these medications is limited by a number of factors including, narrow therapeutic window, drug-drug interactions, problems in standardization of laboratory assays for the measurement of anticoagulation intensity, and complex organization of treatment monitoring required for the optimal treatment results. New era in the management of thromboembolism has arrived with the development of novel oral anticoagulant drugs (NOAC s) that act by inhibiting a single anticoagulant protein in the coagulation cascade (either activated factor X or thrombin), thus providing a pharmacodynamic advantage over vitamin K antagonists. The results of clinical trials that have compared NOAC s and vitamin K antagonists in the prevention and treatment of thromboembolism have demonstrated differences between these two groups of drugs regarding both efficacy (thrombosis prevention) and safety (bleeding risk) that could be attributed to a different mechanism of action. These pharmacodynamic differences have an impact on the future development of pharmacological thromboprophylaxis but also enable individualized treatment of the affected patients with respect to their thromboembolic and hemorrhagic risk.

Transvenous extraction of an eight-year-old ventricular lead accidentally implanted into the left ventricle

Incorrect implantation of a ventricular pacemaker (PM) lead into the left ventricle (LV) is a known problem associated with permanent pacing. The optimal management of such cases identified late has not been clearly established. Generally acceptable management options are: open-chest cardiac surgery using cardio-pulmonary bypass, chronic anticoagulation and antiplatelet-drugs therapy. Rarely, the problem is solved by percutaneous LV lead extraction. We present a case of a patient with DDD pacing and ventricular lead implanted incorrectly into the LV apex region via an atrial septal defect eight years ago. Chronic PM pocket infection developed after replacement of the device. Both leads were extracted percutaneously, and the embolic protection system (Filter-Wire EZ, Boston Scientific) was used to reduce cerebral circulation embolism. The hardest connective tissue adhesions affecting the lead and the anodal ring were found in the LV. Less dense surrounding fibrous tissue around the lead was present at all levels of the venous course of the lead and in the right atrium. Very small fragments of apparently connective tissue remnants were found in cerebral circulation protection filters, and had been removed after the procedure. We conclude that old, permanently implanted LV leads may be extracted percutaneously, especially when there is an increased risk of cardiac surgery, or where the patient's consent for surgical treatment is lacking. In order to perform the procedure it is recommended to establish a cerebral protection system and intraoperative transoesophageal echocardiography which are mandatory for successful lead removal.

Abstract 9549: Influence of Physical Activity on Warfarin Dose, Anticoagulation Response and Risk of Hemorrhagic Complications

Importance: Response to warfarin is influenced by a multitude of patient-specific factors including genetics, clinical comorbidities, and concomitant medications. Objective: To determine the influence of consistent physical activity on stable warfarin dose (mg/day), anticoagulation control (percent-time-in-target-range; PTTR) and risk of major hemorrhage among patients on chronic anticoagulation therapy. Methods: Physical activity was ascertained by self-report at initiation of warfarin therapy (target INR=2-3) in 1276 patients with changes documented at monthly anticoagulation clinic visits. The association of consistent physical activity (maintained over >80% of visits) on warfarin response and anticoagulation control was evaluated using multi-variable linear regression analysis and for major hemorrhage using survival analysis. Results: The number of participants who were consistently physically active (>30 minutes >3 times/week) were 683 (53.7%). Physically active patients required 6.9% higher warfarin doses (p=0.006) and achieved better, although not statistically significant, anticoagulation control (50% vs. 48%; p=0.13) with fewer clinic visits (1.9 vs. 2.5 per patient/ month; p<0.0001) compared to physically inactive patients after accounting for demographic, clinical and genetic factors. There were 137 major hemorrhagic events encountered over 1801 person years of follow-up (incidence 7.6/100pyrs; 95% CI: 6.4 -8.9). The incidence of hemorrhage was lower among physically active patients (5.6/100pyrs; 95% CI: 4.2-7.2) compared to inactive patients (10.3/100 pyrs; 95% CI: 8.2-12.9; p=0.0004). Active patients had a 38% lower risk of hemorrhage (HR: 0.62, 95% CI: 0.42-0.98, p= 0.03) compared to inactive patients after adjusting for bleeding risk (HAS-BLED score), clinical and genetic factors. Conclusion and Relevance: Consistent physical activity is associated with higher warfarin dose requirements but with improved anticoagulation control and lower risk of hemorrhage. In addition to the beneficial effects of physical activity to health and longevity, its influence on drug response needs to be better understood and the mechanisms through which physical activity exerts these effects need to be elucidated.

Hemorrhagic complications of chronic anticoagulant treatment in a single intensive care unit

There are well defined indications in which chronic anticoagulant treatment has been widely applied. However, complications of this therapy are less discussed, although these complications may lead to serious or even fatal consequences. The aim of the authors was to analyze data of patients admitted to their multidisciplinary intensive care unit for complications of chronic anticoagulant therapy between January 1, 2006 and December 31, 2011. Data of 73 patients admitted for serious hemorrhagic complications of chronic anticoagulant therapy were retrospectively analysed. Of the 73 patients, 63 patients had intracranial bleeding, most of them with traumatic origin. A few patients with other hemorrhagic complications such as spinal hematoma, gastrointestinal bleeding, hemorrhagic cystitis, hemothorax and intraabdominal bleeding were also noted. The INR values were out of therapeutic range in 43 patients. The mortality of patients was very high in spite of complex intensive care; 49 of the 73 patients (75.5%) died due to hemorrhagic complications. Due to the high proportion of traumatic origin, the large number of out-of-range INR, and the high mortality, the authors strongly believe that regular patient follow-up, transmission of detailed information, and time-to-time reevaluation of the indications and contraindications of chronic anticoagulant therapy could help to decrease the number of serious and fatal complications of chronic anticoagulant therapy.

Patients with Atrial Fibrillation Undergoing Total Joint Arthroplasty Increase Hospital Burden

More than 3 million people in the United States have atrial fibrillation, most of whom are being managed with anticoagulation therapy for life. The goal of the present study was to examine the effect of chronic anticoagulation therapy on patients with atrial fibrillation who undergo total joint arthroplasty. We retrospectively reviewed all patients undergoing aseptic primary or revision total joint arthroplasty at our facility from March 2007 to August 2011. One hundred and sixty-one patients with atrial fibrillation (Group A) were compared with 161 matched controls (Group B). A total of 112 hips and 210 knees underwent 239 primary arthroplasties and eighty-three revisions. The groups were compared with use of conditional logistic regression (with matching on the basis of the involved joint [hip or knee], type of procedure [revision or primary], age, and sex) with regard to the length of hospital stay, postoperative hemoglobin levels, transfusion requirements, and readmissions. The preoperative length of stay (1.7 versus 0.2 days; p < 0.0001), postoperative length of stay (4.6 versus 3.2 days; p = 0.0002), and total length of stay (6.3 versus 3.4 days; p < 0.0001) were significantly longer for patients with atrial fibrillation (Group A). Hemoglobin levels were lower (but not significantly so) for Group A at baseline (13.1 versus 13.8 mg/dL), on Postoperative Day 2 (10.1 versus 10.6 mg/dL), on Postoperative Day 3 (9.8 versus 10.2 mg/dL), on Postoperative Day 4 (9.6 versus 10.1 mg/dL), on Postoperative Day 5 (9.7 versus 9.9 mg/dL), and at discharge (9.9 versus 10.3 mg/dL). Group A had a significantly higher prevalence of blood transfusion (15.5% versus 3.7%; p = 0.0005) and periprosthetic joint infection (5.6% versus 0.62%; p = 0.0196). A diagnosis of atrial fibrillation (odds ratio, 4.09; 95% confidence interval, 2.05 to 8.18; p < 0.0001) significantly increased the odds of total joint arthroplasty complication and the need for hospital readmission. Patients with preoperative atrial fibrillation undergoing total joint arthroplasty had an increased length of hospital stay, increased transfusion requirements, and an increased risk of periprosthetic joint infection and unplanned hospital readmission.

Plaque disruption during transcatheter aortic valve replacement

A 91-year-old man with a history of hypertension, hyperlipidaemia, coronary artery disease, and atrial fibrillation on chronic anticoagulation therapy presented with symptomatic aortic valve stenosis. The patient underwent a transcatheter aortic valve replacement (TAVR) using an 18-French delivery catheter. A live 3D transoesophageal echocardiogram (TOE) obtained during the procedure revealed an atherosclerotic plaque in the …

Does chronic warfarin cause increased blood loss and transfusion during lumbar spinal surgery?

Background contextThe use of oral anticoagulation therapy such as warfarin is projected to increase significantly as the population ages and the prevalence of cardiovascular disease increases. Current recommendations state that warfarin be discontinued before surgery and the international normalized ratio (INR) normalized. PurposeTo determine if stopping warfarin 7 days before surgery and correcting INR had any effect on intraoperative blood loss or the requirements for blood product transfusion. Study design/settingThis was a retrospective cohort study in a high-volume tertiary care center. Patient sampleSample comprised 263 consecutive patients who underwent elective lumbar spinal surgery. Outcome measureThe outcome measures were intraoperative blood loss, intraoperative blood transfusion, postoperative blood transfusion, and the number of blood products transfused. MethodsThe records of patients undergoing elective spinal surgery were analyzed for patient demographic data, comorbidities, coagulation panel laboratory findings, operative characteristics, blood loss, and blood transfusion requirements. These included patients undergoing full laminectomies with or without posterolateral fusion and instrumentation. Patients on warfarin were analyzed for the mean dosage of warfarin and underlying pathology that required anticoagulation. All patients on warfarin had their anticoagulation therapy stopped 7 days before surgery and their INR checked preoperatively to confirm normalization. Both univariate and multiple linear regression analyses were performed. ResultsThe patients on warfarin had a mean intraoperative blood loss of 839 mL compared with 441 mL for patients not on warfarin (p<.01). Multiple regression analysis determined that warfarin and number of spinal levels decompressed/fused/instrumented were predictors for increased blood loss (R2=0.37). Patients on warfarin also had increased postoperative blood transfusions (23.1% compared with 7.4%, p=.04). There was no significant difference between groups in terms of intraoperative blood transfusion or number of units transfused. ConclusionsPatients on chronic anticoagulation therapy with warfarin who have their therapy stopped 7 days before surgery and have their INR normalized still demonstrated increased intraoperative blood loss and requirement for postoperative transfusion. Surgeons should be aware of the increased propensity of these patients to bleed despite adherence to protocols and should attempt to mitigate this risk.

Pulmonary Artery Perforation by Plug Anchoring System After Percutaneous Closure of Left Appendage

Patients receiving oral anticoagulant therapy for atrial fibrillation who are at high risk of bleeding are increasingly referred for percutaneous left atrial appendage exclusion. Although effective, this procedure is not free from risk. We report a case of pericardial tamponade due to pulmonary artery tear caused by a trespassing anchoring hook of an AGA plug. Intraoperatively, no actual bleeding was found from the left appendage, a proof of its complete occlusion by the device. The patient underwent successful surgical repair and radio-frequency ablation of atrial fibrillation was performed by pulmonary veins encircling.

Antithrombotic Therapy for Patients with Nonvalvular Atrial Fibrillation Undergoing Percutaneous Coronary Intervention: A Review

Patients with atrial fibrillation who have risk factors for thromboembolism benefit from chronic oral anticoagulation therapy, and antiplatelet therapy alone is of relatively little benefit for prevention of ischemic stroke and systemic embolism. Patients undergoing percutaneous coronary intervention with drug-eluting stents require dual antiplatelet therapy with aspirin and a thienopyridine for 3 to 12 months or more prevention of stent thrombosis and recurrent ischemic events. When patients with atrial fibrillation undergo percutaneous coronary intervention, the need to combine dual antiplatelet therapy and warfarin raises the risk of major bleeding complications considerably. Recent trials have explored the option of omitting aspirin with promising results. The introduction of novel oral anticoagulants that specifically inhibit factor IIa (dabigatran) or factor Xa (rivaroxaban, apixaban, and edoxaban) and antiplatelet agents that inhibit the P(2)Y(12) receptor (prasugrel and ticagrelor) makes management of these patients even more challenging, but future trials addressing myriad alternative regimens may identify better tolerated strategies.

Warfarin Users Prone to Coagulopathy in First 30 Days After Hospital Discharge from Gastric Bypass

Lehigh Valley Health Network (LVHN), a nonprofit tertiary care facility in Allentown, Pennsylvania, is an accredited American College of Surgeons Bariatric Surgery Center Network (ACSBSCN) Level 1 site performing 400+ bariatric procedures annually. Bariatric data submission began in April 2008. Complication review revealed that approximately 17% of patients on chronic anticoagulation (warfarin) therapy preoperatively were readmitted with supratherapeutic international normalized ratios (INRs), postsurgical bleeding, anastomotic ulcer, or other intraluminal hemorrhage. Opinion level recommendations have been published regarding the adjustment of warfarin dosages post-bariatric procedures with no widespread consensus. Case series have been published detailing perioperative hemorrhage risk for bariatric patients on preoperative anticoagulation. Little data of post-discharge hemorrhage rates have been published. With increasing numbers of bariatric surgical procedures performed annually, there is a potential for developing serious coagulopathic complications in those patients who resume their anticoagulation therapy postoperatively. Retrospective review of LVHN data from the ACSBSCN database was analyzed for 30-day readmissions due to documented extra- or intraluminal hemorrhage with INR and coagulopathy. Follow-up INR and warfarin doses were collected up to 6months postoperatively. Over a 3-year period, 38 patients undergoing bariatric procedures were identified as being on preoperative warfarin therapy. Six of 38 developed hemorrhage within 30days. Two patients presented beyond 30days with bleeding. Supratherapeutic INR was present in five of six readmitted patients. Mean INR was 5.8. Warfarin sensitivity was present in a statistically significant higher number of patients within 30days of surgery. After 30days, a resistance to warfarin was demonstrated. Bariatric surgery patients taking warfarin are prone to coagulopathy in the early post-op period requiring vigilant monitoring to prevent supratherapeutic INR and corresponding risk of hemorrhage.

8. Barrett’s esophagus – A perfect target for cryo-ablation

Endoscopic cryotherapy is used for a variety of indications in the gastrointestinal tract, including treatment of chronic gastric antral vascular ectasia (GAVE), radiation proctitis, and Barrett’s esophagus. Barrett’s esophagus (BE) is a known precursor to esophageal adenocarcinoma resulting from chronic gastroesophageal reflux disease. Endoscopic treatment of high grade neoplasia (high grade dysplasia) and early adenocarcinoma in Barrett’s esophagus is the preferred first line approach for most patients. This includes endoscopic mucosal resection (EMR) for nodular disease or focal neoplastic lesions, and mucosal ablation for flat neoplasia. Current ablative techniques include treatment with heat energy (such as radiofrequency ablation or RFA), cryogen (cryotherapy or cryoablation), and laser plus photosensitizing drug therapy (photodynamic therapy). Although less widely available and studied compared to RFA, endoscopic cryotherapy using liquid nitrogen or compressed gas such as carbon dioxide or nitrogen have excellent safety and efficacy profiles. The complete response rates for elimination of high grade neoplasia in Barrett’s esophagus are comparable to those of RFA, whether it is used for primary or salvage therapy. Cryotherapy can also be applied when RFA is contraindicated or associated with greater risk (such as in patients with esophageal strictures, radiation therapy, eosinophilic esophagitis, cardiac defibrillators, on chronic anti-platelet or anticoagulation therapy). Furthermore, a few studies of cryotherapy also demonstrate long term response rates for endoscopic treatment and palliation of esophageal adenocarcinoma, which cannot be treated with RFA. The incidence of side effects of cryotherapy, when used properly, is lower than that of RFA, particularly with less post-treatment pain and dysphagia. Patients can usually resume a normal diet, unlike RFA. Lastly, the current systems and cost of cryotherapy are significantly lower than that of RFA or photodynamic therapy. New methods of applying endoscopic cryotherapy are being developed to improve the portability and technical ease. Cryotherapy is an excellent mucosal ablative technique for the gastrointestinal tract.

Effect of chronic oral anticoagulation with warfarin on the durability and outcomes of endovascular aortic aneurysm repair

Endoleak after endovascular aortic aneurysm repair (EVAR) can affect the durability of the repair and lead to continued sac expansion, rupture, and the need for further endovascular or open surgical interventions. The purpose of this study was to determine whether chronic anticoagulation therapy with warfarin is associated with an increased incidence of endoleak and thus increased need for reintervention after EVAR. We reviewed the records of 401 consecutive patients who underwent EVAR at a single institution from 2003 until 2011. Patients on warfarin were compared with a control group not on warfarin. Primary endpoints included reintervention, defined as rupture, explant, or angiography; death from any cause; and a composite outcome of reintervention or death. The presence of an endoleak at last follow-up, identified by computed tomography or ultrasound scan, and increase of more than 5 mm in aneurysm sac size were secondary endpoints. Cox proportional hazards models were used to estimate the effect of warfarin use on the primary and secondary outcomes, controlling for age, gender, obesity, specific comorbidities, antiplatelet drugs, statin use, and urgency of EVAR. Three hundred sixty-three patients with a median follow-up period of 29 months had sufficient data for analysis. Warfarin use was not associated with an increased risk of any of the primary endpoints. Controlling for covariates and length of observation via proportional hazards models, the effect of warfarin remained insignificant. It was found, however, on regression analysis, that adverse outcomes were more prevalent after emergency EVAR and in patients deemed unfit for open surgical repair. Chronic oral anticoagulation does not appear to affect the incidence of endoleak after EVAR, nor does it impact the need for reintervention or degree of sac regression. We feel that warfarin may be safely used in post-EVAR patients. It appears that adverse long-term outcomes are more likely after emergency EVAR and in patients deemed unfit for open surgery.

Management of Patients With Atrial Fibrillation (Compilation of 2006 ACCF/AHA/ESC and 2011 ACCF/AHA/HRS Recommendations)

This document is a compilation of the current American College of Cardiology Foundation/American Heart Association (ACCF/AHA) practice guideline recommendations for atrial fibrillation (AF) from the “ACC/AHA/ESC 2006 Guidelines for the Management of Patients With Atrial Fibrillation),”* the “2011 ACCF/AHA/HRS Focused Update on the Management of Patients With Atrial Fibrillation (Updating the 2006 Guideline)”† and the “2011 ACCF/AHA/HRS Focused Update on the Management of Patients With Atrial Fibrillation (Update on Dabigatran).”‡ Updated and new recommendations from 2011 are noted and outdated recommendations have been removed. No new evidence was reviewed, and no recommendations included herein are original to this document. The ACCF/AHA Task Force on Practice Guidelines chooses to republish the recommendations in this format to provide the complete set of practice guideline recommendations in a single resource. ### 1.1. Pharmacological and Nonpharmacological Therapeutic Options #### 1.1.1. Rate Control During AF Class I 1. Measurement of the heart rate at rest and control of the rate using …

Gastrointestinal complications after cardiac surgery: 10-year experience of a single Australian centre

Gastrointestinal (GI) complications after cardiac surgery are uncommon, but are associated with high morbidity and mortality as well as significant hospital resource utilization. We analysed a prospectively collected database containing all adult cardiac surgery procedures performed from July 2001 to March 2011 at Monash Medical Centre and Jessie McPherson Private Hospital. Patients with post-operative GI complications were compared to patients without GI complications who were operated in the same period. The incidence of GI complications was 1.1% (61 out of 5382 patients) with an overall 30-day mortality of 33% (versus 3% in the non-GI complication group). The most common complications were GI bleeding, gastroenteritis and bowel ischaemia. Patients who had GI complications were significantly older, had higher incidence of renal impairment, chronic lung disease and anticoagulation therapy and were more likely to be in cardiogenic shock. Emergency procedures, combined coronary artery bypass grafting and valve surgery and aortic dissection cases were more common in the GI complication group. The GI complication group also had higher incidence of return to theatre, renal failure, stroke, septicaemia and multi-organ failure. GI complications after cardiac surgery remain an uncommon but dreadful complication associated with high mortality. Our findings should prompt a high degree of clinical vigilance in order to make an early diagnosis especially in high risk patients. Further studies aiming to identify independent predictors for GI complications after cardiac surgery are warranted.

Late MitraClip procedure after left atrial appendage occlusion

We report the first human case of percutaneous edge-to-edge mitral valve repair using MitraClip System (Abbott Vascular, Abbott Park, IL) in a patient, who previously underwent left atrial appendage closure with PLAATO™ System (ev3. Inc., Plymouth, MN). The procedure was successfully performed using the standard MitraClip technique, in the catheterization laboratory, with transesophageal echocardiographic and fluoroscopic guidance. We showed that a double percutaneous procedure for stroke prevention and mitral regurgitation treatment might be a valid approach in selected patients ineligible for chronic anticoagulation therapy and at high risk for conventional cardiac surgery.

The use of vitamin K supplementation to achieve INR stability: A systematic review and meta-analysis

Systematically review and quantitatively synthesize evidence on use of oral vitamin K supplementation in reducing international normalized ratio (INR) variability. PubMed, The Cochrane Library, PsycINFO, Cumulative Index of Nursing and Allied Health Literature (CINAHL), Turning Research Into Practice (TRIP), Web of Science were searched for studies meeting predetermined inclusion/exclusion criteria. Five studies meeting criteria (three randomized trials, one quasi-experimental pre-post study, one retrospective case series) were appraised for quality and data synthesized by two reviewers. Pooled effect size of time in INR therapeutic range (TTR) was estimated using random effects meta-analysis. Pooled effect size representing data from four studies (678 subjects) was 0.31, 95% confidence interval 0.03-0.59 (Cochran Q = 7.1; p = .07; I(2) = 57.8) and favored vitamin K supplementation. Given wide variability among individual studies, there is not enough evidence to advise for or against the routine use of vitamin K supplementation to achieve INR stability. However, evidence does suggest that it may be of some benefit for some patients with INR instability. There is insufficient evidence to support routine supplementation with vitamin K in patients on chronic anticoagulation therapy but select patients, particularly those with persistent INR instability despite known adherence to regimen and no dietary or drug-drug interactions, may benefit from the intervention. Future research is warranted.

In Vitro Evaluation of a Novel Hemodynamically Optimized Trileaflet Polymeric Prosthetic Heart Valve

Calcific aortic valve disease is the most common and life threatening form of valvular heart disease, characterized by stenosis and regurgitation, which is currently treated at the symptomatic end-stages via open-heart surgical replacement of the diseased valve with, typically, either a xenograft tissue valve or a pyrolytic carbon mechanical heart valve. These options offer the clinician a choice between structural valve deterioration and chronic anticoagulant therapy, respectively, effectively replacing one disease with another. Polymeric prosthetic heart valves (PHV) offer the promise of reducing or eliminating these complications, and they may be better suited for the new transcatheter aortic valve replacement (TAVR) procedure, which currently utilizes tissue valves. New evidence indicates that the latter may incur damage during implantation. Polymer PHVs may also be incorporated into pulsatile circulatory support devices such as total artificial heart and ventricular assist devices that currently employ mechanical PHVs. Development of polymer PHVs, however, has been slow due to the lack of sufficiently durable and biocompatible polymers. We have designed a new trileaflet polymer PHV for surgical implantation employing a novel polymer-xSIBS-that offers superior bio-stability and durability. The design of this polymer PHV was optimized for reduced stresses, improved hemodynamic performance, and reduced thrombogenicity using our device thrombogenicity emulation (DTE) methodology, the results of which have been published separately. Here we present our new design, prototype fabrication methods, hydrodynamics performance testing, and platelet activation measurements performed in the optimized valve prototype and compare it to the performance of a gold standard tissue valve. The hydrodynamic performance of the two valves was comparable in all measures, with a certain advantage to our valve during regurgitation. There was no significant difference between the platelet activation rates of our polymer valve and the tissue valve, indicating that similar to the latter, its recipients may not require anticoagulation. This work proves the feasibility of our optimized polymer PHV design and brings polymeric valves closer to clinical viability.

Fetal Demise due to Uterine Trauma With Massive Intraperitoneal Hemorrhage Associated With Chronic Perforation of the Inferior Vena Cava by an Infrarenal Filter: A Case Report With Call for Definitive Consensus Regarding Filter Positioning in Nonpregnant Women of Childbearing Age

Suprarenal placement of inferior vena cava (IVC) filters in women of childbearing age has been recommended largely based upon theoretic concerns for safety of the mother and fetus. However, cases of filter-related maternal and fetal injuries have not been previously reported. Instructions for use of commercially available permanent and retrievable IVC filters do not make distinctions based on age or sex. Although most IVC filters implanted in current practice are potentially retrievable, less than 50% are ever removed. We present the first report of serious maternal injury and fetal death resulting from uterine trauma related to chronic perforation of the IVC by an infrarenal filter, initially placed in a nonpregnant woman of childbearing age. A 36-year-old nonpregnant woman was treated with chronic anticoagulation therapy (AT) because of recurrent episodes of pulmonary embolism (PE). She developed a retroperitoneal hemorrhage due to warfarin toxicity, at which point, an infrarenal Trapease IVC filter was placed. Indefinite AT with low-molecular-weight heparin was later initiated. Chronic perforation of the IVC by the filter was incidentally noted 2 years later. Filter removal by percutaneous means was contraindicated, and given her asymptomatic status, operative removal was not offered. One year later, at age 39, she became pregnant. At an estimated intrauterine pregnancy age of 24 weeks, after physical activity, the patient developed sudden, extreme abdominal and back pain with associated dyspnea. A pulmonary computed tomography angiogram demonstrated no PE but showed free intraperitoneal fluid. She became hemodynamically unstable, concurrent with dramatic fall in fetal heart rate. Laparotomy and caesarean section were immediately performed, but the fetus was not salvageable. Bleeding was noted from a laceration to the dome of the uterus and was closed with chromic suture. A tear was noted in the peritoneal membrane overlying the filter, with barbs and vertical struts of the filter freely exposed. The vertical struts and barbs of the filter were removed, but due to instability, complete removal of the filter and IVC reconstruction was not deemed safe. Instead, the filter-bearing IVC was wrapped with a vascularized, transmesocolic omental flap. The patient's hospital course, 13 days, was complicated by intraperitoneal abscess (drained percutaneously) and wound infection. Complete healing was achieved at 10 weeks postoperatively. The patient is doing well at 4 months. Chronic AT with low-molecular-weight heparin has been continued, and the patient advised to avoid future pregnancies. Interaction between the gravid uterus and an infrarenally positioned IVC filter, presumed in the past to be a theoretic risk for IVC compression and thrombosis or perforation, is proven by this case to be a real risk. Although the filter in this case was a permanent type, use of an optional filter does not obviate this risk, because a large majority of optional filters are never removed. Societal consensus and device manufacturers should address this potential risk in guidelines for filter placement, positioning (preferably suprarenal), and emphasis on subsequent, planned filter retrieval when IVC filters are placed in nonpregnant women of childbearing age.

The minimally invasive approach is associated with reduced perioperative thromboembolic and bleeding complications for patients receiving preoperative chronic oral anticoagulant therapy who undergo colorectal surgery

The data on the perioperative risk of both thromboembolism and hemorrhage for patients receiving chronic oral anticoagulation who undergo colorectal surgery are sparse. In addition, it is uncertain whether the use of the laparoscopic instead of open technique entails additional risk for these patients. This study aimed to evaluate surgical outcomes, with a particular focus on perioperative thromboembolic and bleeding complications for patients receiving chronic oral anticoagulation therapy who undergo open or laparoscopic colorectal resection. Patients undergoing colorectal resection between 1994 and 2011 on preoperative chronic oral anticoagulant therapy were included in the study. Patient demographics, characteristics, and perioperative outcomes, with particular emphasis on thromboembolism and bleeding risks, were evaluated comparing laparoscopic and open colectomy. The study enrolled 261 patients receiving chronic anticoagulation therapy (102 laparoscopic colectomy vs 159 open colectomy patients). The patients had a mean age of 57.9 years and a mean body mass index (BMI) of 29.3 kg/m(2). The conversion rate was 8.8 % (n = 9) for laparoscopic operations. Laparoscopic and open cases had comparable BMIs and levels of preoperative hemoglobin. Anastomotic leak, postoperative hospital stay, and surgical-site infection rates were similar for the two groups. Although the laparoscopic group had a significantly greater mean age (p < 0.001) and American Society of Anesthesiology (ASA) score (p = 0.005), the rates for postoperative venous thromboembolism (24.5 vs 2.9 %; p < 0.001), urinary complications (6.9 vs 0 %; p = 0.008), and overall morbidity (44.7 vs 17.7 %; p < 0.001) were lower after laparoscopic surgery. Although the rates for intra- and postoperative blood transfusion were similar, the postoperative hemoglobin levels were significantly higher after laparoscopic surgery. One patient in the laparoscopic group died of sepsis on postoperative day 3. For the patients receiving preoperative chronic anticoagulant therapy who underwent colorectal resection, the laparoscopic approach was associated with lower thromboembolic and hemorrhagic complications than open surgery.

Trifecta or Triple Threat? The Challenge of Post-PCI Management in Patients Receiving Chronic Oral Anticoagulant Therapy

We are fortunate to practice in an era of medicine which has many proven therapies. However, we are increasingly faced with coadministration of therapies whose combined effects have not been fully evaluated. Perhaps the most common and difficult of these scenarios is the use of dual antiplatelet therapy in patients who require chronic oral anticoagulation. Although each of these treatments has clear benefits, there is concern about bleeding risk when they are used together. Physicians are forced to choose between risking a thromboembolic or a bleeding complication. To best serve our patients, we must consider not only our initial reaction to do no harm, but go through the slower process of calculating the risk and severity of all possible adverse effects. However, for this process to succeed, we need robust data on which to base these calculations. This issue of the Canadian Journal of Cardiology (CJC) contains 2 articles which provide much-needed data. In the first, Ho and colleagues study the most common group of patients requiring chronic anticoagulation—individuals with atrial fibrillation. Their single-centre Canadian study included 602 patients with atrial fibrillation as their only indication for anticoagulation who underwent percutaneous coronary intervention (PCI) between 2008 and 2009. All were treated with dual antiplatelet therapy using aspirin and clopidogrel. The study was not randomized; however, physicians elected to treat 382 patients with triple therapy (ie, continued warfarin along with dual antiplatelet therapy), and 220 patients received dual antiplatelet therapy alone. Physicians clearly favoured triple therapy among patients with a higher risk of stroke, as patients receiving triple therapy were older (72.9 vs 70.5 years, P 0.039), were more likely to have suffered a previous stroke (14.4% vs 6.4%, P 0.01) and had a higher Congestive Heart Failure, Hypertension, Age, Diabetes, Stroke/Transient Ischemic Attack CHADS2 score (2.6 vs 2.1; P 0.001). 6