Adequate Anticoagulation Research Articles

Heart failure and the risk of left atrial thrombus formation in patients with atrial fibrillation or atrial flutter.

The aim of the study was to evaluate the prevalence of left atrial thrombus (LAT) on transoesophageal echocardiography (TOE) in patients with atrial fibrillation or atrial flutter (AF/AFl) with reference to the presence of heart failure (HF) and its subtypes. The research is a sub-study of the multicentre, prospective, observational Left Atrial Thrombus on Transoesophageal Echocardiography (LATTEE) registry, which comprised 3109 consecutive patients with AF/AFl undergoing TOE prior to direct current cardioversion or catheter ablation. TOE parameters, including presence of LAT, were compared between patients with and without HF and across different subtypes of HF, including HF with preserved (HFpEF), mid-range (HFmrEF), and reduced ejection fraction (HFrEF). HF was diagnosed in 1336 patients (43%). HF patients had higher prevalence of LAT than non-HF patients (12.8% vs. 4.4%; P<0.001). LAT presence increased with more advanced type of systolic dysfunction (HFpEF vs. HFmrEF vs. HFrEF: 7.4% vs. 10.5% vs. 20.3%; P<0.001). Univariate analysis revealed that HFrEF (odds ratio [OR] 4.13; 95% confidence interval [95% CI]: 3.13-5.46), but not HFmrEF or HFpEF, was associated with the presence of LAT. Multivariable logistic regression indicated that lower left ventricular ejection fraction (OR per 1%: 0.94; 95% CI 0.93-0.95) was an independent predictor of LAT formation. Receiver operator characteristic analysis showed LVEF ≤48% adequately predicted increased risk of LAT presence (area under the curve [AUC] 0.74; P<0.0001). The diagnosis of HFrEF, but neither HFmrEF nor HFpEF, confers a considerable risk of LAT presence despite widespread utilization of adequate anticoagulation.

Extracorporeal membrane oxygenation after prosthetic valve replacement in a child with neonatal Marfan syndrome: a case report

BackgroundNeonatal Marfan syndrome (nMFS), the most severe form of Marfan syndrome, is a rare condition that presents a clinical and treatment challenge. nMFS has high infant mortality related to progressive valvular dysfunction. Valve replacement in this setting improves long-term prognosis but carries high morbidity and mortality. Thus, sharing clinical experience in treating such patients is valuable.Case summaryA 2 year old with nMFS underwent tricuspid valve annuloplasty and prosthetic mitral valve replacement. Postoperative management was complicated by pulmonary hypertension, cardiogenic shock, and arrythmias. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) helped overcome these challenges but posed a high risk for prosthetic valve thrombosis (PVT). Despite decompression of the left atrium (LA) with an LA vent, the left ventricle (LV) was distended because of aortic regurgitation and no native cardiac output. We lowered the ECMO flow under echocardiographic guidance; used inodilators and pacing to encourage transmitral flow and reduce LV afterload. The patient completed a successful 6-day ECMO run with good end-organ perfusion. At last follow up, she was 6 years old, enjoying school, home-ventilated through the tracheostomy, and mobilizing with walking aids/wheelchair.DiscussionValve replacement can improve life quality and expectancy for patients with nMFS. Lowering ECMO flow under echocardiography guidance till the aortic valve is seen to open; coupled with inodilators, pacing and adequate anticoagulation can be a safe way to deliver VA-ECMO for cardiogenic shock after prosthetic valve replacement. Further research is needed to show if this strategy prevents prosthetic valve thrombosis and provides sufficient haemodynamic support and myocardial rest.

Antiphospholipid antibody syndrome presenting as foot gangrene after bilateral total knee arthroplasty: A case report

Case: A 71 years old female who underwent bilateral total knee replacement, noted discolouration of toes and plantar aspect of right foot, along with cold right foot, 1 week after surgery due to thrombosis of dorsalis pedis artery in spite of adequate anticoagulation. She was eventually diagnosed with Anti phospholipid antibody (APLA) syndrome. Conclusion: APLA is not routinely investigated in preoperative workup for arthroplasty. It is also not a common condition in orthopaedic practice. Some patients may develop thrombosis after arthroplasty in spite of adequate thromboprophylaxis and a rare cause like APLA has to be kept in mind to help in ensuring appropriate treatment.

Case report of anesthesia for free fibula flap reconstruction in Ewing sarcoma: Safety and efficacy of continuous popliteal sciatic nerve block and very low doses of intravenous heparin

A child with a maxillary Ewing sarcoma was operated for tumor asportation and reconstruction with free fibula flap. Adequate anticoagulation was achieved with lower doses of heparin and monitored with multiple ACT values. We used NIRS monitoring to avoid hypoperfusion. Post‐operative pain relief was guarantited by local anestethic continous infusion.

Anticoagulation Strategies in Pediatric Cardiopulmonary Bypass, Weight-Based vs. Concentration-Based Approaches

Pediatric patients undergoing cardiopulmonary bypass (CPB) require adequate anticoagulation to combat hemostatic activation. Heparin is used to bind and catalyze antithrombin III (ATIII) that works to inhibit clot formation. To dose heparin, a weight-based (WB) or patient-specific concentration-based (PSCB) method can be used. The WB protocol calculates the dose based on the patients’ weight and uses an activated clotting time (ACT) test to ensure anticoagulation. The ACT has limitations during CPB especially for pediatric patients who have immature hemostatic systems. The PSCB method predicts the patients’ response to heparin by projecting a heparin dose–response (HDR) curve. Some investigators have found benefit to using the PSCB method but further investigation into how well the HDR predicts the heparin response is needed. A literature review was conducted for studies that looked at heparin management strategies in pediatric CPB patients between 1992 and 2020. Articles that focused on pediatric physiology, heparin management strategies, and anticoagulation were included. Articles older than 1990 were excluded. The literature review highlights that utilizing the PSCB approach more adequately anticoagulated patients. The WB protocol was found to have several flaws due to its reliance on the ACT, especially in infants. The results show that further investigation is needed to understand why there is benefit to using the PSCB approach. Observing the association between the HDR curve and subsequent heparin concentrations could determine how accurately it predicts the patients’ response to heparin and why there is benefit to using this method.

A CASE OF INTERMITTENT HEMOPTYSIS: THE SPECTRUM OF ANTIPHOSPHOLIPID ANTIBODY SYNDROME

TYPE: Late Breaking Case Report TOPIC: Pulmonary Manifestations of Systemic Disease INTRODUCTION: A 46 year old WM presented with several years of intermittent hemoptysis. Symptoms resolve spontaneously, improve with diuresis or required antibiotics/steroids. Evaluation for infection was negative and was maintained on daily prednisone with benefit. Malaise, hypoxemia, edema with hemoptysis but no other associated symptoms. CASE PRESENTATION: Past medical history includes CVA at age 24 related to antiphospholipid antibody syndrome and treated with anticoagulation. No other organ involvement reported. Medical history: CKD, HTN, non-ischemic cardiomyopathy. Remote 15PY tobacco history, no other exposures. On exam, room air O2 saturation 92%, desaturation to 70s with exertion. Oropharynx class III Mallampati score, lungs clear, CV RRR, no murmurs, gallops, extremities with lower extremity edema, no clubbing, rashes, ecchymosis, petechiae. Evaluation: negative ANA, DS-DNA, ENA, ANCA, anti-GBM, anti-CCP Ab. Normal immunoglobulins, complements and positive lupus anticoagulant. Chemistries: elevated creatinine, WBC 13.1, Hemoglobin 10.5, platelets 89. BNP 659, normal urinalysis. PFTs: restriction and reduced DLCO. Cardiac echo: moderately dilated LV, LVEF 40%, normal right ventricular size and function. CT chest showed diffuse bilateral pulmonary ground glass opacities. DISCUSSION: Clinical course included empiric antibiotics, bronchoscopy, heart failure management, high-dose steroids, and cyclophosphamide initiation for diffuse alveolar hemorrhage. He had clinical improvement but required readmission with progressive pulmonary symptoms, acute renal failure, and an acute ischemic stroke despite adequate anticoagulation. This met criteria for Catastrophic Antiphospholipid Antibody Syndrome. He was treated with plasma exchange, steroids/cyclophosphamide and rituximab. CONCLUSIONS: This case represents the spectrum of disorders seen in antiphospholipid antibody syndrome. Antiphospholipid antibody syndrome can have a broad range of presentation in the lungs. DISCLOSURE: Nothing to declare. KEYWORD: ANTIPHOSPHOLIPID ANTIBODY SYNDROME

Anticoagulation Strategies in Pediatric Cardiopulmonary Bypass, Weight-Based vs. Concentration-Based Approaches.

Pediatric patients undergoing cardiopulmonary bypass (CPB) require adequate anticoagulation to combat hemostatic activation. Heparin is used to bind and catalyze antithrombin III (ATIII) that works to inhibit clot formation. To dose heparin, a weight-based (WB) or patient-specific concentration-based (PSCB) method can be used. The WB protocol calculates the dose based on the patients' weight and uses an activated clotting time (ACT) test to ensure anticoagulation. The ACT has limitations during CPB especially for pediatric patients who have immature hemostatic systems. The PSCB method predicts the patients' response to heparin by projecting a heparin dose-response (HDR) curve. Some investigators have found benefit to using the PSCB method but further investigation into how well the HDR predicts the heparin response is needed. A literature review was conducted for studies that looked at heparin management strategies in pediatric CPB patients between 1992 and 2020. Articles that focused on pediatric physiology, heparin management strategies, and anticoagulation were included. Articles older than 1990 were excluded. The literature review highlights that utilizing the PSCB approach more adequately anticoagulated patients. The WB protocol was found to have several flaws due to its reliance on the ACT, especially in infants. The results show that further investigation is needed to understand why there is benefit to using the PSCB approach. Observing the association between the HDR curve and subsequent heparin concentrations could determine how accurately it predicts the patients' response to heparin and why there is benefit to using this method.

A CASE OF PERSISTENT IN-SITU PULMONARY THROMBOSIS DESPITE LONG-TERM ANTICOAGULATION THERAPY

TYPE: Case Report TOPIC: Pulmonary Vascular Disease INTRODUCTION: In-situ pulmonary thrombosis refers to de novo thrombus formation in the pulmonary arteries without any distant source. In-situ thrombosis has been associated with radiation therapy and lung lobectomy. However, little is known about thrombosis resolution after anticoagulation therapy. We present a case of a patient with a persistent pulmonary thrombus despite adequate anticoagulation therapy. CASE PRESENTATION: A 70-year-old male with a past medical history of chronic obstructive lung disease, right-sided lobectomy secondary to non-small cell lung cancer, and subsequent restrictive lung disease due to lobectomy and radiation therapy presented to the pulmonary clinic with shortness of breath. Further evaluation that included a CT scan of the chest with contrast revealed an incidental in-situ thrombosis in the right main pulmonary artery extending into the right upper lobar branch. There was no evidence of cancer recurrence. Previous imaging did not reveal a similar thrombosis. Venous duplex and echocardiography were normal. The patient was anticoagulated with rivaroxaban for over nine months and remained on anticoagulation. Despite this, follow-up imaging has not demonstrated resolution, propagation, or improvement of the thrombus. After optimization of his comorbidities, the patient has remained symptom-free. DISCUSSION: In-situ pulmonary thrombosis may be associated with prior lung radiation therapy and lobectomy. While studies have shown that most pulmonary embolisms resolve over three months with anticoagulation, little is known about the resolution of in-situ thrombosis. CONCLUSIONS: Pulmonary thrombosis may become chronic despite anticoagulation. Therefore, it may be clinically relevant to identify the speed of clot resolution for evaluating patients with suspected recurrent thrombosis. DISCLOSURE: Nothing to declare. KEYWORD: IN-SITU PULMONARY THROMBOSIS, RADIATION THERAPY, LOBECTOMY, ANTICOAGULATION

MO318: Utility of D-Dimer Levels in Predicting the Renal Outcome of Acute Kidney Injury in Moderate and Severe COVID-19: A Retrospective Study

BACKGROUND AND AIMSAcute kidney injury (AKI) is a potential complication of COVID-19 and the hypercoagulation tendency of SARS-CoV-2 infection is considered one of the underlying mechanisms. Fibrinolysis markers have been described as severity parameters, independent of clinically manifested thromboembolic events. The aim of this study is to evaluate the contribution of D-dimer testing in appreciating the extent of AKI and renal function recovery in COVID-19.METHODWe have conducted a retrospective study on 253 AKI adult patients confirmed with SARS-CoV-2 infection by molecular testing and hospitalized in two emergency university hospitals over the course of 6 months. Diagnosis and staging of AKI were performed with KDIGO 2012 criteria. We analysed the impact of peak D-dimers on the severity of AKI, recovery of renal function and need for renal replacement therapy (RRT). Additionally, we searched the relationship between D-dimers and survival and COVID-19 severity parameters. Severity of respiratory failure was classified as mild-moderate (no support or low-flow oxygen) and severe (mechanical ventilation: continuous positive airway pressure and endotracheal intubation). All data was analysed using IBM SPSS Statistics v.25 (IBM, Corp.).RESULTSThe average age was 72.4 ± 13.33 years, 159 patients were male (62.84%). According to KDIGO staging, 79 patients were in stage 1, 74 in stage 2 and 100 patients in stage 3. Overall mortality was 50.59% (N = 128). The mean peak of D-dimers was 6.08 ± 6.53 µg/mL. We found a significant direct relationship between D-dimers and AKI stage (3.72 ± 5.84 µg/mL—stage 1; 6.67 ± 6.60 µg/mL—stage 2; 7.50 ± 6.46 µg/mL—stage 3; P < .0001). There was a significant inverse relationship between D-dimers and odds of renal recovery, lower values being noted in the complete renal recovery group (3.79 ± 5.10 µg/mL, N = 77) compared with partial recovery (5.22 ± 6.89 µg/mL, N = 57; P < .02), while D-dimers were strikingly high in patients needing RRT (8.11 ± 5.92 µg/mL, N = 29). Regarding the severity of respiratory failure, we found that mild-moderate cases had lower D-dimers (4.23 ± 5.46 µg/mL, N = 146) compared with severe failure (8.60 ± 7.00 µg/mL, N = 107; P < .003). Intensive care unit (ICU) admission was also correlated with levels of D-dimers (8.55 ± 6.76 µg/mL, N = 107 versus non-ICU 4.27 ± 5.70 µg/mL, N = 146; P < .01). D-dimers were higher in deceased patients (7.91 ± 6.60 µg/mL) compared with survivors (4.20 ± 5.88 µg/mL; P < 0.001) (Table 1).Table 1.CountN (%)Peak D-dimer levels (average ± SD; µg/mL)Statistical significance (P-value)Entire cohort2536.08 ± 6.53AKI severityKDIGO stage 1KDIGO stage 2KDIGO stage 3 79 (31.22)74 (29.24)100 (39.52) 3.72 ± 5.846.67 ± 6.607.50 ± 6.46 P < .0001*Kruskal–Wallis H TestRecovery of renal functionTotalPartialNeed for HDNone (excl. death) 77 (30.43)57 (22.52)29 (11.46)8 (3.16) 3.79 ± 5.105.22 ± 6.898.11 ± 5.926.25 ± 5.75 P < .02*Kruskal–Wallis H TestAKI timingAt admissionDuring hospitalization 172 (67.98)81 (32.01) 5.75 ± 6.336.77 ± 6.86 P = .307, ns**Mann–Whitney U TestRespiratory supportNone/low-flow oxygenCPAP/ETI 146 (57.7)107 (42.29) 4.23 ± 5.468.60 ± 7.00 P < .003**Mann–Whitney U TestICUNon-ICU107 (42.29)146 (57.70)8.55 ± 6.764.27 ± 5.70 P < .001**Mann–Whitney U TestMortalitySurvivedDeceased 125 (49.40)128 (50.59) 4.20 ± 5.887.91 ± 6.60 P < .001**Mann–Whitney U TestSD, standard deviation; HD, haemodialysis; CPAP, continous positive airway pressure; ETI, endotracheal intubation; ICU, intensive care unit; and ns, not significant.CONCLUSIONIncreased D-dimer levels in COVID-19-associated AKI have a negative impact on the severity of AKI, need for RRT and recovery of renal function. AKI patients with high levels of D-dimers are more often admitted to the ICU, have an increased need for mechanical ventilation and have poor survival. Due to the additional negative impact of AKI in COVID-19 and possible preventability of severe disease, D-dimers may be a useful tool to assess the need and duration of adequate prophylactic anticoagulation.

Potential critical risks of pulmonary thromboembolism from an asymptomatic postpartum ovarian vein thrombosis: a case report

BackgroundOvarian vein thrombosis (OVT) may cause maternal mortality by inducing pulmonary thromboembolism (PTE). However, the prevalence, etiology, risk factors, prognosis, and optimal treatments for asymptomatic OVT during and after pregnancies are unclear, which therefore requires a high clinical index of suspicion for certain diagnoses due to its vague presentation. We herein present a case of asymptomatic postpartum OVT that extended toward the inferior vena cava (IVC), resulting in a potential risk of PTE.Case presentationA 30-year-old postpartum woman presented with slight dyspnea after an uneventful vaginal delivery at 40 weeks of gestation. We checked her laboratory data to exclude lethal thrombosis; D-dimer levels were 85.6 μg/mL. We performed computed tomography (CT) to search the presence of PTE and deep vein thrombosis (DVT); although no signs of PTE and DVT in her legs were detected, CT and trans-abdominal ultrasonography (TAUS) revealed a right OVT. Heparin was administered, and D-dimer levels decreased; warfarin at a dose of 2 mg/day was subsequently administered to control anti-coagulopathy. However, D-dimer was re-elevated despite adequate anticoagulation treatment, and extension of the right OVT to the IVC was detected by CT and TAUS. With warfarin administration, CT and TAUS showed the disappearance of right OVT. The patient was discharged from the hospital 17 days after delivery.ConclusionsEven asymptomatic postpartum OVT may lead to PTE. Universal screening guidelines and optimal treatment strategies for asymptomatic OVT in pregnant and postpartum women should be established through future studies.

Value Of Blood Volume Analysis In Patients With Left Ventricular Assist Devices.

Introduction Implantable left ventricular assist devices (LVAD) have dramatically changed the face of mechanical circulatory support of patients with advanced heart failure. With increased durability, reliability and safety these devices have extended the horizon of functional improvement, life quality and survival. Beyond crucial pre-operative and intra-operative issues, several device-host interface issues are important for successful outcomes. Among these are clear understanding of intravascular volume status, red blood cell volume status. Blood volume analysis (BVA) is a blood test that measures these 3 metrics using the indicator dilution technique, with rapid personalized and actionable results. We used BVA to evaluate 10 consecutive stable ambulatory patients supported with LVAD. Results The patients were seven men and three woman aged 32-70 years. Duration of LVAD support at the time of outpatient BVA (Daxor, Oak Ridge, TN) ranged from 46-1460 days. Two out of eight patients had LVAD (HM3(5), HW(4), HM2(1)implanted as bridge to transplant, all others as destination therapy. Eight out of ten patients were obese with deviations from normal body weight of 22-117% and average BMI of 32.6. All patients were felt to be improved and stable compared to pre-LVAD (INTERMACS 1-3) and none had evidence of device malfunction or drive line infection. All patients had variations in total blood volumes, plasma volume and red cell volume (Table1). Only two out of ten patients had all three BVA parameters within normal limits. Half of the patients had significant hypervolemia, which was not suspected on physical exam. Two out of ten patients had significant hypervolemia with polycythemia, which was not clinically suspected. Conclusions In summary, BVA and its individualized, unique metrics is a valuable test when used in patients with LVAD's. Despite improved functional status and adequate device performance wide variations are still present in patients being supported with LVAD's. Additionally, measurement of red blood cell volume is helpful in determined variations (anemia or polycythemia) that might not be noted clinically and might presage future hemolytic and/or thrombotic events despite adequate anticoagulation. Implantable left ventricular assist devices (LVAD) have dramatically changed the face of mechanical circulatory support of patients with advanced heart failure. With increased durability, reliability and safety these devices have extended the horizon of functional improvement, life quality and survival. Beyond crucial pre-operative and intra-operative issues, several device-host interface issues are important for successful outcomes. Among these are clear understanding of intravascular volume status, red blood cell volume status. Blood volume analysis (BVA) is a blood test that measures these 3 metrics using the indicator dilution technique, with rapid personalized and actionable results. We used BVA to evaluate 10 consecutive stable ambulatory patients supported with LVAD. The patients were seven men and three woman aged 32-70 years. Duration of LVAD support at the time of outpatient BVA (Daxor, Oak Ridge, TN) ranged from 46-1460 days. Two out of eight patients had LVAD (HM3(5), HW(4), HM2(1)implanted as bridge to transplant, all others as destination therapy. Eight out of ten patients were obese with deviations from normal body weight of 22-117% and average BMI of 32.6. All patients were felt to be improved and stable compared to pre-LVAD (INTERMACS 1-3) and none had evidence of device malfunction or drive line infection. All patients had variations in total blood volumes, plasma volume and red cell volume (Table1). Only two out of ten patients had all three BVA parameters within normal limits. Half of the patients had significant hypervolemia, which was not suspected on physical exam. Two out of ten patients had significant hypervolemia with polycythemia, which was not clinically suspected. In summary, BVA and its individualized, unique metrics is a valuable test when used in patients with LVAD's. Despite improved functional status and adequate device performance wide variations are still present in patients being supported with LVAD's. Additionally, measurement of red blood cell volume is helpful in determined variations (anemia or polycythemia) that might not be noted clinically and might presage future hemolytic and/or thrombotic events despite adequate anticoagulation.

Recurrent Pump Thromboses in an LVAD Patient with Chronic Lymphocytic Leukemia

<h3>Introduction</h3> There is limited literature regarding the management of LVAD patients with concomitant hematologic malignancies. This case report describes a patient with chronic lymphocytic leukemia (CLL) who developed recurrent pump thromboses after LVAD implantation. <h3>Case Report</h3> A 66-year-old man with a past medical history of ischemic cardiomyopathy requiring HeartWare implant, CLL, and secondary polycythemia presents with recurrent pump thromboses. After an uneventful 17 months, the patient presented with gross hematuria, elevated LDH, and high pump parameters. Chronic antithrombotic therapy (AT) was per center protocol with warfarin (goal INR 2-3, time in therapeutic range [TTR] 65%) and aspirin. Hgb levels were elevated with an average of 14.0g/dL over the prior 3 months. Upon admission, he was treated with heparin without improvement in LDH or symptoms. Therapy was then escalated to alteplase (two bolus regimen of 10mg push over 1 minute and a 1mg/min push over 20 minutes followed by an extended infusion dosed at 1mg/hr for 45 hours), with improvement in LDH, pump parameters, and no adverse events. AT was intensified at discharge (INR goal 2.5-3.0, ticagrelor added) and oncology was consulted to manage Hgb levels outpatient with therapeutic phlebotomy for a goal of <12g/dL. Patient had 2 more events of pump thromboses, 2.5 and 15 months after the first and second events, respectively - both of which responded to alteplase. Hgb was at goal after the first event but was temporarily elevated 8 months prior to third event following a course of IV iron. After the second event, AT was altered to enoxaparin 1mg/kg q12hr and aspirin, given warfarin failure (two thrombotic events with above average TTR); ticagrelor was discontinued in the event an urgent pump exchange was needed. After the third event, AT was intensified again by resuming ticagrelor. Pump exchange was deferred given improvements in LDH and resolution of symptoms. In an LVAD patient with CLL, escalating AT was insufficient. Targeting a lower Hgb level, to reduce the resistance within the pump, may be beneficial. <h3>Summary</h3> Hematologic malignancies can pose an increased risk of thrombosis despite appropriate anticoagulation, and management can be challenging in LVAD patients. More aggressive control of hemoglobin in addition to adequate anticoagulation is critical in managing these patients.

Short-Term Postoperative Use of Rivaroxaban to Prevent Radial Artery Occlusion After Transradial Coronary Procedure: The RESTORE Randomized Trial.

Adequate procedural anticoagulation is crucial for radial artery occlusion (RAO) prevention in patients undergoing transradial access coronary catheterization, although the effect of postprocedural anticoagulation lack thorough investigation. The aim of this study was to evaluate the clinical value of short-term postoperative anticoagulation with rivaroxaban for 24 hours and 1-month RAO prevention in patients who received transradial coronary procedures. A total of 382 patients were randomized to receive either placebo (control group) or rivaroxaban 10 mg once daily for a period of 7 days (rivaroxaban group) to evaluate the effect of the rivaroxaban in the prevention of 24 hours and 1-month RAO assessed by Doppler ultrasound. There was no significant difference in the incidence of 24-hour RAO (8.9% versus 11.5%; P=0.398) between the rivaroxaban group and control group (odds ratio, 0.75 [95% CI, 0.39-1.46]; P=0.399). In contrast, the 1-month RAO (3.8% versus 11.5%; P=0.011) was significantly reduced in patients who received rivaroxaban as compared with those who did placebo (odds ratio, 0.22 [95% CI, 0.08-0.65]; P=0.006). For patients with 24-hour RAO, the rivaroxaban group was associated with higher recanalization rate of the radial artery (69.2% versus 30.0%; P=0.027) compared with the control group. No significant differences can be observed between the 2 groups for access-site complications or bleeding events. Short-term postoperative anticoagulation with rivaroxaban did not reduce the rate of 24-hour RAO but improved 1-month RAO, because of higher recanalization of the radial artery. However, larger clinical trials are needed to prove our results. URL: https://www.chictr.org.cn; Unique identifier: ChiCTR1900026974.

Familial Essential Thrombocythemia With Novel MPL L502G and G208K Mutations

Familial essential thrombocythemia is characterized by the inheritance of germline mutations to progeny, thereby increasing the risk for the development of essential thrombocythemia. Here, we present two cases of young women who developed thromboembolic phenomena, one of whom with an ischemic event despite adequate anticoagulation. Through extended mutational testing, both were characterized as having novel mutations in the myeloproliferative leukemia virus (MPL) gene, and both individuals have fathers being treated for essential thrombocythemia. This case provides insight that in familial essential thrombocythemia, there remain uncharacterized mutations in this inherited conditional landscape.

Weight Based Heparin Dosage with Activated Clotting Time Monitoring Leads to Adequate and Safe Anticoagulation in Non-Cardiac Arterial Procedures

Unfractionated heparin has an unpredictable effect in an individual patient. The activated clotting time (ACT) can be used to measure the effect of heparin in the individual patient and guide additional heparin dosages. Previous cohort studies showed that a standardized bolus of 5,000 IU during noncardiac arterial procedures (NCAP) does not lead to an adequate ACT in the vast majority of patients. The aim of this study was to investigate whether an initial heparin dose of 100 IU/kg leads to an adequate but safe ACT, from 200 to 300s. In this multicenter prospective study, 186 patients undergoing NCAP were enrolled and received an initial heparin dose of 100 IU/kg. Target ACT was set at ≥250s initially; during the course of the study the target ACT was lowered to ≥200s. After the initialheparin dose, additional heparin dosages were administered depending on the ACT values following a heparin dose protocol. ACT measurements and complications were monitored. The mean baseline ACT was 134±17s. The mean ACT 5minutes after the initial heparin dose was 227±37s. After the initial dose of heparin, 78 and 46% of patients reached an ACT of 200 and 250s, respectively. Seven patients (4%) reached an ACT of 300s or more. Ninety-four patients (51%) received at least one additional dose of heparin. After one additional dose of heparin, 91% of patients reached an ACT of 200s and 13 patients (7%) reached an ACT of 300s or more. Arterial thromboembolic complications occurred in 4.3% and bleeding complications occurred in 9.7%. A bolus of 100 IU/kg of heparin during NCAP results in adequate coagulation in most patients. ACT measurements enable accurate additional dosing, ensuring the individual patient tailored and safe coagulation. anticoagulants; heparin; blood coagulation tests; vascular surgical procedures; peripheral vascular disease.

Anticoagulation Therapy in Endovascular Thrombectomy Patients With Large‐Vessel Occlusion Caused by Cardioembolism

Background In patients with ischemic stroke, cardioembolism, predominantly caused by atrial fibrillation (AF), is a leading preventable cause of large‐vessel occlusion (LVO). Despite proven efficacy, inadequate oral anticoagulant (OAC) therapy continues to be a major problem in patients with AF, mechanical heart valves, and other potential sources of emboli. We aimed to determine rates of cardioembolic LVO, the adequacy of OAC, and the association of OACs with clinical outcomes in patients with LVO treated with endovascular thrombectomy (EVT). Methods Consecutive patients with cardioembolism treated with EVT were included and had pre‐stroke indication for OACs and the adequacy of anticoagulation determined. The primary outcome was 3‐month functional independence (modified Rankin Scale score 0–2). Secondary outcomes included early neurological recovery (reduction in National Institutes of Health Stroke Scale score ≥8 points, or score of 0–1 at 24 hours), symptomatic intracranial hemorrhage, and 3‐month mortality and modified Rankin Scale score. Results There were 784 patients treated with EVT, of whom 416 (53.1%; 231 men; mean±SD age, 67.1±15.9) had cardioembolic LVO. Of those with cardioembolism, 221 (53.1%) had prevalent AF, 99 (23.8%) incident AF, 48 (11.5%) mechanical heart valves, 10 (2.4%) left ventricular thrombus, and 38 (9.1%) other cardioembolic causes. A total of 242 patients were identified as having a pre‐stroke indication for OACs, and 67 (27.7%) of these patients were considered adequately anticoagulated at time of LVO. In all 242 patients with cardioembolism with a pre‐stroke indication for OACs, adequate anticoagulation was not associated with EVT outcomes. However, adequate anticoagulation in patients with prevalent AF was associated with lower rates of internal carotid artery occlusion (6.8% versus 18.9%; P =0.03) and higher rates of functional independence (odds ratio=1.94; 95% CI, 1.02–3.78]; P =0.04). Conclusions Over half of patients treated with EVT were assessed as having a cardioembolic cause. Just over a quarter of patients with an indication for OACs at the time of LVO were adequately anticoagulated. These figures suggest that a substantial number of EVT procedures may have been avoided if more patients had been adequately anticoagulated.

Assessment of curbside anticoagulation pharmacy visits on clinical outcomes and patient satisfaction

AbstractIntroductionDuring the coronavirus disease 2019 (COVID‐19) pandemic, curbside international normalized ratio (INR) checks were implemented to monitor patients on warfarin therapy. Because of the lack of available data, clinical outcomes and patient satisfaction were assessed to determine if the implementation of curbside visits could be considered as an alternative to the standard of care.ObjectivesThe objectives were to assess clinical outcomes, safety, and patient satisfaction in a patient cohort whose anticoagulation was managed inside the clinic in 2019 compared with the same patients managed in the curbside setting in 2020.MethodsIn this retrospective study, INR time in therapeutic range (TTR) was used as a marker for clinical appropriateness of anticoagulation therapy. Data were also prospectively collected in the form of patient satisfaction surveys. Adverse events and hospitalizations were assessed to ensure patient safety was not omitted.ResultsThe median TTR in 2019 was significantly higher than in 2020, 95.7% (interquartile range [IQR] 33.3%) vs 84.3% (IQR 45.2%) (z = −3.99, P &lt; .001). Clinically, the mean TTR remained higher in 2019 than in 2020 (81.3% vs 74.7%). Less patients experienced bleeding events in 2020, and there was an average of 1 less visit per patient in 2020 compared with 2019. Surveys indicated that more patients would like their visits to occur inside the clinic if there were no concerns for a pandemic.ConclusionAnticoagulation management assessed by TTR was significantly lower in the 2020 time frame compared with 2019; however, the average TTR in both time frames was above the clinically accepted threshold of adequate anticoagulation control. Patients demonstrated favor toward in‐person visits unless there were concerns for a pandemic. If needed, curbside visits could be considered in the future at this site; however, more studies would need to be done to assess the impact of curbside visits at other institutions.

Abstract WP168: Anticoagulation Therapy In Endovascular Thrombectomy Patients With Large Vessel Occlusion Due To Cardioembolism

Introduction: In ischemic stroke patients, cardioembolism, predominantly due to atrial fibrillation (AF), is a leading preventable cause of large vessel occlusion (LVO). Despite proven efficacy, inadequate oral anticoagulant (OAC) therapy continues to be a major problem in patients with AF, mechanical heart valves and other potential sources of emboli. Aim: To determine rates of cardioembolic LVO, the adequacy of OAC, and the association of OACs with clinical outcomes in LVO patients treated with endovascular thrombectomy (EVT). Methods: Trial of Org 10172 in Acute Stroke Treatment classification was used to determine stroke etiology in consecutive patients treated with EVT. Pre-stroke indication for OAC and the adequacy of anticoagulation were determined for patients with cardioembolic LVO. The primary outcome was 3-month functional independence (modified Rankin Scale score 0-2). Secondary outcomes included early neurological recovery (reduction in National Institutes of Health Stroke Scale score ≥8 points, or score of 0-1 at 24-hours), symptomatic intracranial hemorrhage, and 3-month mortality and modified Rankin Scale score. Results: Between January 2015 and December 2020, 784 patients were treated with EVT. There were 416 patients (213 men; mean±SD age 67.1±15.9) with cardioembolic LVO, including 221 (53.1%) prevalent AF, 99 (23.8%) incident AF, 48 (11.5%) mechanical heart valve, 10 (2.4%) cardiomyopathy-related LVO, 10 (2.4%) left ventricular thrombus-related LVO and 11 (2.6%) patent foramen ovale-related LVO patients. There was adequate anticoagulation in 8 (16.7%) mechanical heart valve patients. Of the 191 prevalent AF patients with pre-stroke indications for OAC, 59 (30.9%) patients had adequate anticoagulation, and were less likely to have internal carotid artery occlusion (6.8% versus 18.9%, P =0.03) and more likely to achieve functional independence (OR=1.97 [95% CI 1.01-3.83]; P =0.04) than those with inadequate anticoagulation. Conclusion: Over half of EVT treated patients had cardioembolic LVO. Only one-third of patients with an indication for OAC at the time of LVO were adequately anticoagulated. This suggests that up to one in five patients with LVO requiring EVT may have been prevented with adequate anticoagulation.

LONG-TERM AMBULATORY ECG MONITORING AN ESSENTIAL DIAGNOSTIC TOOL FOR CURRENT TIMES

Ambulatory ECG (AECG) monitoring with diary correlation of symptoms has been proven to provide significant diagnostic, therapeutic and prognostic benefit with an arrhythmic cause of symptoms. Arrhythmias can range from premature atrial and ventricular complexes (APCs/ PVCs usually benign), to Atrial and Ventricular Fibrillation which causes significant morbidity and mortality. Symptoms such as palpitations, shortness of breath, chest pain and syncope are common during arrhythmias and their frequency determines the choice of investigation needed to diagnose the arrythmia.&#x0D; Arrhythmias can be a manifestation of many cardiac and non-cardiac diseases. These also include congenital diseases and are often missed due to inadequate monitoring. Since most arrhythmias are intermittent they are more likely to be detected during extended ECG monitoring. Other uses of ambulatory ECG devices include ST segment analysis, heart rate variability, signal averaged ECGs, diurnal QT and QTc analysis (including patients with long QT) (1) obstructive sleep apnea and vectorcardiography (2). These factors have been shown to have relation to significant cardiovascular diseases aiding the diagnosis of various arrhythmias.&#x0D; Syncope although mostly benign, could potentially be a consequence of a life-threatening arrhythmia in up to 20% patients(3). Nonetheless syncope poses a significant cause of disturbance in a patients’ life and definitive diagnosis is necessary to ensure patients well-being.&#x0D; ESC Guidelines on Syncope (2018) recommend further testing with AECG via Holter monitoring, wearable patch recorder, external and internal loop recorders etc. depending on the frequency after initial examination is negative for a definite cause.&#x0D; Atrial Fibrillation (AF) increases risk of stroke more than five times. Atrial Fibrillation diagnosed after stroke is an important hallmark of recurrent stroke risk. (7) Many studies have demonstrated post stroke AECG increases the chances of detecting AF (15% vs 5%) when compared to standard monitoring. An increase incidence in atrial arrythmias (atrial high rate episodes AHRE) has been seen in patients with Permanent Pacemakers which should be documented by AECG to be treated accordingly.(4). Uses can be prognostic if rate was to be monitored in AF to assess efficacy of rate control treatment and offer adequate anticoagulation according to the 2020 ESC atrial fibrillation guidelines. (8)&#x0D; Some limitations of twenty-four hours Holter monitoring have recently been overcome by improvements in hardware and software technology including adhesive patches and wireless telemetry. Newer adhesive patches are softer, waterproof and electrode free monitors which offer unprecedented mobility and ease of carrying out daily routine by the patient. They operate as either recorders or wireless streaming devices (5). These devices were safe and effective during the pandemic even when delivered home through mail to critically ill patients.(6)&#x0D; The advent of smart phones has added endless potential for recording through wireless Bluetooth transmission. Smart devices like the OMSHIRTtm have the added advantage of being comfortable to wear. Newer devices for example Cardiostat has been shown to offer equal quality tracings when compared to standard Holter monitoring, often up to the 99% sensitivity and specificity through better designed R wave (QRS) detection algorithms(7) (8)Studies have shown these newer devices to be easily operable and can even be mailed to patients homes for self-attachment with an equal efficacy to hospital applied machine (6).&#x0D; Many studies have shown a preference over intra cardiac monitors (ICM) due to these above mentioned advantages (9). The effectiveness of even longer recordings through Implantable Loop Recorder has also been satisfactory when following patients after Ablation therapy leading to practice updating guideline changes in rhythm management(10).&#x0D; A recent review article summarized that although physicians in the US had knowledge of how and when to offer monitoring devices based on the frequency of symptoms, they were often seen prescribing Holter monitoring due to familiarity. Data also showed that in case the initial investigation was inconclusive, the physician would still repeat the same investigation(3).&#x0D; In a country like Pakistan where there are limited resources, diagnosis and management of arrythmias still has a long way to go. This article sheds light on the need of utilizing the recommended available devices.

Contemporary Practice of Heparin Prescription and Its Monitoring via Activated Clotting Time in Percutaneous Coronary Intervention in Victoria, Australia

Adequate anticoagulation during percutaneous coronary intervention (PCI) with unfractionated heparin (UFH) is the standard practice to minimise thrombotic complications. Current international guidelines lack clarity on the use of activated clotting time (ACT) to measure the adequacy of anticoagulation during and post PCI, and the need for UFH supplementation post PCI.