Lower Thrombosis Rate Research Articles

Pulmonary embolism or thrombosis in ARDS COVID-19 patients: A French monocenter retrospective study.

Hypercoagulability and endotheliopathy reported in patients with coronavirus disease 2019 (COVID-19) combined with strict and prolonged immobilization inherent to deep sedation and administration of neuromuscular blockers for Acute Respiratory Distress Syndrome (ARDS) may expose critically ill COVID-19 patients to an increased risk of venous thrombosis and pulmonary embolism (PE). We aimed to assess the rate and to describe the clinical features and the outcomes of ARDS COVID-19 patients diagnosed with PE during ICU stay. From March 13th to April 24th 2020, a total of 92 patients (median age: 61 years, 1st-3rd quartiles [55–70]; males: n = 73/92, 79%; baseline SOFA: 4 [3–7] and SAPS II: 31 [21–40]; invasive mechanical ventilation: n = 83/92, 90%; ICU mortality: n = 45/92, 49%) were admitted to our 41-bed COVID-19 ICU for ARDS due to COVID-19. Among them, 26 patients (n = 26/92, 28%) underwent a Computed Tomography Pulmonary Angiography which revealed PE in 16 (n = 16/26, 62%) of them, accounting for 17% (n = 16/92) of the whole cohort. PE was bilateral in 3 (19%) patients and unilateral in 13 (81%) patients. The most proximal thrombus was localized in main (n = 4, 25%), lobar (n = 2, 12%) or segmental (n = 10, 63%) pulmonary artery. Most of the thrombi (n = 13/16, 81%) were located in a parenchymatous condensation. Only three of the 16 patients (19%) had lower limb venous thrombosis on Doppler ultrasound. Three patients were treated with alteplase and anticoagulation (n = 3/16, 19%) while the 13 others (n = 13/16, 81%) were treated with anticoagulation alone. ICU mortality was higher in patients with PE compared to that of patients without PE (n = 11/16, 69% vs. n = 2/10, 20%; p = 0.04). The low rate of lower limb venous thrombosis together with the high rate of distal pulmonary thrombus argue for a local immuno-thrombotic process associated with the classic embolic process. Further larger studies are needed to assess the real prevalence and the risk factors of pulmonary embolism/thrombosis together with its prognostic impact on critically ill patients with COVID-19.

Systematic review of microvascular coupling devices for arterial anastomoses in free tissue transfer.

BackgroundCoupling devices have become commonplace in performing venous anastomoses during microvascular free tissue transfer (FTT). However, arterial anastomoses are still most commonly performed using traditional microvascular suture techniques.ObjectiveTo describe the safety and feasibility of using microvascular coupling devices for free flap arterial anastomosis.MethodsA systematic review of English language literature was performed for studies that investigated the use of an arterial coupler for microvascular FTT in human patients. A comprehensive search of MEDLINE (January 1948 to August 2018), EMBASE (January 1974 to August 2018), and Web of Science was performed.ResultsFifteen studies were included. All studies were retrospective case series. A combined total of 395 arterial anastomoses were attempted with a coupling device. All studies except for one used the 3M Unilink/Synovis coupling device. One study used a novel absorbable coupling device. The coupling device was aborted and converted to a suture technique in 8.4% of attempted anastomoses. Rupture of the anastomotic device was reported in only 1 patient (0.3%). Thrombosis was also infrequent at 1.9%. The quality assessment showed a high risk of bias in all studies.ConclusionIn selected patients, coupling devices for arterial anastomoses have a good success rate with low rates of thrombosis based on limited quality evidence.

Hybrid Thrombolysis for Left Ventricular Assist Device Thrombosis

LVAD thrombolysis can be effective but carries a bleeding risk. Existing data suggest intraventricular (vs peripheral) delivery may reduce bleeding, but is associated with early recurrence. We have developed a novel hybrid thrombolytic approach (hTL) using an initial high dose LV delivery of alteplase followed by a maintenance LV infusion. We studied all patients with durable LVAD pump thrombosis (PT) treated with hTL in our institution between 1/2015 and 9/2019. We report the technique, procedural success and complications. We identified 10 patients with median (IQR) age 56 years (50, 64 years). All had undergone Heartware HVAD implantation. Duration of LVAD support preceding PT was 518 days (172, 920 days). All patients had significant increases in power and haemolysis markers, and were treated initially with heparin and tirofiban (n=9) or heparin alone (n=1). Time to hTL was 3 days (2, 5 days). hTL was done in the cardiac catheterisation laboratory after informed consent. Heparin and tirofiban were stopped in advance. An arterial sheath was placed in a femoral (n=5) or radial (n=5) artery. A pigtail catheter was advanced to the LV under fluoroscopic guidance. Alteplase was infused at 1mg/min and stopped when LVAD power returned to baseline. The pigtail catheter was left in situ, and the alteplase maintenance infusion continued at 1mg/hour to a weight-adjusted maximum. The sheath and catheter were then removed. Median total alteplase dose was 74mg (48, 90mg). There was acute normalisation of pump power in 8 patients, and 6 remained free of thrombosis at 1 year. Among these 6, 3 were bridged to transplant and 3 continue on LVAD support. In the 2 patients with recurrent thrombus (at days 8 and 37), 1 was managed with inotropes and urgent transplant, and 1 died. In the 2 acute non-responders, 1 went for urgent pump exchange and 1 died. There was no procedure-related bleeding or death. Two patients had vascular access site haematoma (both femoral access), and a further 3 patients had minor bleeding not requiring intervention. Three patients developed acute kidney injury probably related to haemolysis. We report a hTL protocol for LVAD thrombosis with 80% initial success, low rate of recurrent thrombosis, and no major bleeding. Interpretation is limited by small group size and retrospective design. These outcomes require comparison with other approaches, ultimately in a randomised trial.

Double kissing crush and nano crush stenting in left main coronary bifurcation lesions: Besting the rival techniques!

Percutaneous coronary intervention of left main (LM) bifurcation can be technically demanding and is often associated with significant in-stent restenosis in contemporary practice. The heterogeneity of these lesions makes it difficult to establish a consensus as to the best interventional strategy. The provisional one-stent approach has shown a more favorable outcome than two-stent technique in terms of both efficacy and safety. In complex LM bifurcation lesions, double kissing has demonstrated its superiority over culotte and provisional-T in terms of restenosis making it one of the most performed techniques. On the other hand, the nano-crush technique has recently become part of the repertoire of two-stent techniques, providing evidence that the use of ultrathin-strut stents and very minimal crush would be beneficial for both the physiological and rheological properties of the complex LM bifurcations, leading to a lower rate of thrombosis and restenosis at both side branch and true carina. Finally, the newest generation of ultrathin-strut stents is gaining a reputation for its safe and effective use in this scenario thanks to an improved design with increased expansion rate capable of LM treatment up to 5–6 mm diameter. The modern crush techniques, such as double-kiss-crush and nano-crush, are providing excellent results on mid- and long-term follow-up, suggesting that minimal crushing obtained using ultra-thin stents is an excellent way to obtain surgical-like outcomes in the treatment of complex LM bifurcation disease.

Potential Anti-Thrombotic Effect without Accompanying Hemorrhage with Fostamatinib Use in Patients with Immune Thrombocytopenia

Potential Anti-Thrombotic Effect without Accompanying Hemorrhage with Fostamatinib Use in Patients with Immune Thrombocytopenia

A Retrospective Chart Review to Assess Indications, Risk Factors and Complications Associated with the Use of Indwelling Catheters in Pediatric Patients with Sickle Cell Disease - a Single Institution Experience

Background: Sickle cell disease (SCD) and its complications are associated with frequent hospital visits and treatment often requires venous access for administration of fluids, medications and blood transfusions. Due to frequent use, peripheral venous access can become difficult over time because of venous scarring. Moreover, certain interventions such as chronic simple or exchange transfusions require reliable venous access for prolonged periods of time. Implantable central venous devices such as ports offer definitive access and mitigate the need for frequent peripheral access attempts. However, existing knowledge on the use of these devices in pediatric patients with SCD is limited. Due to possible increased risks of thrombosis and mechanical occlusion from hypercoagulable state, risk of infectious complications and need for surgical placement, ports are often not used routinely. We review the indications and complications associated with placement of ports in the pediatric cohort of patients with SCD - to better define the scope of port placement in this group. Methods: We performed an IRB-approved, retrospective chart review to assess the indications, complications and risk factors associated with port placement in children and adolescents with SCD at the University of Oklahoma Health Sciences Center (OUHSC). The study period analyzed was 17.5 years from January 1st, 2000 to July 30th, 2018 and included patients from birth to 21 years of age, diagnosed with SCD who had homozygous sickle cell disease (HbSS) or compound heterozygous SCD - either sickle cell-β0-thalassemia, sickle cell-β+-thalassemia or sickle cell-hemoglobin C (HbSC) disease, and had ports in place for more than 7 days. Patients were identified systematically by querying the OUHSC Clinical Data Warehouse using diagnostic codes followed by chart review. Results: Thirty-two patients with SCD and ports were identified during the study period, out of which 31 patients had HbSS and one patient had HbSC disease. The median age at first port insertion was 8 years (range 1-20 years). A total of 63 ports were placed for a total of 99,272 port days with a median port life span of 1340 days. The two main indications for port placement were - either chronic transfusions for which 48 ports were placed for a total of 80,238 port days, or poor venous access (PVA) for which 15 ports were placed for a total of 19,034 port days. Out of the 48 ports placed for chronic transfusions, 6 ports were for transfusions for primary stroke prophylaxis, 22 ports were for transfusions for secondary stroke prophylaxis, 17 ports were for transfusions for recurrent vaso-occlusive episodes (VOE) and 3 ports were for transfusions after multi-organ failure. A total of 54 port complications occurred (malfunction=29, infection=20, thrombosis=3, difficult port access=1, and intractable pain over port site=1). From the data available, more ports were placed in the left subclavian vein (LSV=20) than right subclavian vein (RSV=4) and right internal jugular (RIJ=2), however rate of overall complications were similar between LSV and RSV - 0.57 complications/1,000 catheter days in LSV and 0.58 complications/1,000 catheter days in RSV. The rate of port associated infection, defined as a positive blood culture drawn from the port, was 0.2 per 1,000 port days. A total of 20 infections identified mostly gram-positive organisms (n=15) predominantly Staphylococcus, compared to gram-negatives (n=3), fungus with Candida albicans (n=1) and a rare acid-fast bacilli infection with Mycobacterium mucogenicum (n=1). The rate of thrombosis, identified radiologically using vascular doppler ultrasound, was 0.03 per 1,000 port days. The rate of premature port removal arising from complications was 0.36 per 1,000 port days. Ports placed for chronic transfusions had a lower rate of removal (0.31 per 1,000 port days) compared to ports placed for poor venous access (0.58 per 1,000 port days) with a ratio of 0.54 which approached statistical significance (p=0.09; CI 0.26-1.21). Conclusion: Ports in pediatric patients with SCD are associated with low rates of thrombosis, infection and malfunction. Ports may be a reasonable alternative for vascular access in patients with SCD - especially in patients who require chronic simple or exchange transfusions and have difficult access. Larger prospective studies will be needed to further assess the scope of use of ports in this population. Disclosures No relevant conflicts of interest to declare.

Bleeding and Thrombotic Outcomes in Anticoagulant Free Extracorporeal Membrane Oxygenation (ECMO) in Adults: A Systematic Review

Background: Extra Corporeal Membrane Oxygenation (ECMO) is being used with increasing frequency in critically ill patients requiring cardiopulmonary life-support. The combined effects of critical illness, ECMO use, and systemic anticoagulation to prevent circuit thrombosis, induces a complex milieu of coagulation, fibrinolytic and platelet derangements. Both bleeding and clotting are expectedly the most frequent and dangerous complications of ECMO; in patients with active or high risk of major bleeding, the prospect of anticoagulation-free ECMO is attractive, although data is limited on the safety and efficacy of this practice. In order to better define the safety of anticoagulation-free ECMO, we performed the following systematic review. Methods: We searched Ovid Medline for publications reporting use of ECMO without therapeutic-dose systemic anticoagulation of any kind for a minimum of 24 hours in adult patients, between the years 1977 to 2019. Studies using general venous thromboembolism prophylaxis were included. We included randomized control trials, cohort studies, case series, and case-control studies that contained sufficient patient-level data. Preclinical studies, meta-analyses, systematic reviews, narrative reviews, and reports involving patients under 18 years of age were excluded. Outcomes of interest collected included all bleeding and thrombotic events involving the patient or circuitry. Results: 443 studies were identified through our search. After removal of duplicates, 441 records were screened. After exclusion, 23 full-text articles were assessed for eligibility. 2 of the full text articles were further excluded due to ambiguity regarding the time patients were off of anticoagulation. 21 studies were ultimately included in the systematic review. These included 8 case series and 13 individual case reports. All were single center studies. Data for a total of 154 patients among all 21 studies analyzed were reviewed. 96 adults were treated with veno-venous (vv) ECMO, and 58 were treated with veno-arterial (va) ECMO. Indications for ECMO included acute respiratory distress syndrome, diffuse alveolar hemorrhage, traumatic brain injury, intra-cranial hemorrhage, and lung transplant. Median total time on anticoagulant-free ECMO was 11.85 days among individual case reports, and 7.03 days for patients included in case series. Of the 154 patients, 9 (5.8%) had new, severe bleeding events, 13 (8.4%) experienced minor bleeding, and 15 (9.7%) were re-explored for bleeding. No new cases of intracranial hemorrhage were seen during ECMO without systemic anticoagulation. 15 patients (9.5%) developed circuitry thrombosis, and 6 (3.9%) developed systemic venous or arterial thrombosis. Full results are listed in Table 1. Conclusions: Our systematic review found that anticoagulant-free ECMO was associated with relatively low rates of major bleeding, circuitry and patient thrombosis; the frequency of these events (5.8%, 9.5%, 3.9%, respectively) is similar, if not lower, than historically-reported rates in ECMO with anticoagulation (at least 16%, 10% and 18%, respectively). Of note, no new instances of intracranial hemorrhage were found, which is crucially important given the high associated mortality. Though based on a small number of patients, our review is valuable as it provides a new perspective on the prevailing theory that systemic anticoagulation is an absolutely necessary component of ECMO to prevent thrombosis. Evolving ECMO technology and improved overall care of critically-ill patients may be contributing to a less thrombotic blood microenvironment, which is typically attributed to inflammation, contact pathway and platelet activation. We acknowledge several limitations of our review, including the identification and inclusion of only non-randomized, retrospective studies, variable definitions and reporting of thrombotic and bleeding events, and likely non-negligible differences in ECMO technology, all of which precludes any definitive conclusions. Our findings are, however, hypothesis-generating; prospective, randomized trials would help better clarify the safety and efficacy of ECMO without anticoagulation, and address a unmet medical need by refining anticoagulation indications for critically ill patients on ECMO. Disclosures Shatzel: Aronora, Inc.: Consultancy.

Research quality in the study of mechanical methods of deep vein thrombosis prophylaxis.

There is a lack of good-quality recent clinical data to support the use of mechanical methods to prevent deep vein thrombosis. Recommendations and meta-analyses have to rely on old data from evaluations of devices that are no longer available, with diagnostic methods that are obsolete. The aim of this narrative review is to examine the reasons why better recent evidence is not available, and how this will affect innovation in mechanical deep vein thrombosis prophylaxis. Analysis of recent published trials shows great variability in techniques and technologies, which complicates evaluation of the effectiveness of properties of intermittent pneumatic compression, graduated compression stockings, and electrical stimulation devices. Negative controlled trials have become difficult to conduct, and low rates of deep vein thrombosis have left many comparative trials of devices underpowered. There is a risk that if new approaches to enable clinical research are not developed that technological advancement of mechanical prophylaxis will be inhibited.

Do two venous anastomoses decrease venous thrombosis during limb reconstruction?

The optimal number of veins to be anastomosed in perforator flaps for limb reconstruction and its influence on the results remain controversial. Venous thrombosis of microvascular anastomoses is a commonly recorded complication in soft tissue reconstruction. To evaluate the effect of two venous anastomoses in the incidence of venous thrombosis for limb reconstruction using anterolateral thigh (ALT) microsurgical free flaps. This was a cross-sectional study on patients undergoing limb reconstruction using ALT flap during 2014-2017. Perioperative information was recorded and patients were divided in two groups: group 1 (one venous anastomosis; 17 patients) and group 2 (two venous anastomoses; 21 patients). Complications were investigated. Overall, 38 microsurgical flaps were included. The mean age was 33 years, and 32 patients were male. The most prevalent wounds were traumatic. Group 1 presented a higher complication rate than group 2 (47% vs. 24%; p = 0.065), although the difference was not significant. Group 1 presented a higher rate of venous anastomotic thrombosis (p = 0.032) than group 2. The overall success rate was 92%. For limb reconstruction using ALT microsurgical free flaps, two venous anastomoses are associated with a low rate of venous thrombosis in microvascular anastomoses.

A systematic follow-up protocol achieving a low hemodialysis graft thrombosis rate.

Graft is an alternative to native arteriovenous fistula to ensure permanent vascular access in hemodialysis patients. The most common complication is significant stenosis, which frequently causes thrombosis and graft loss. Periodic monitoring and surveillance with elective correction of stenotic lesions can prolong graft survival. To describe the effect of early diagnosis of significant stenosis on the rate of thrombosis and graft patency. Retrospective, observational study of a cohort of 86 prevalent patients undergoing hemodialysis with a graft as their vascular access. We applied a systematic follow-up protocol of 115 grafts based on various screening methods of monitoring (clinical monitoring, pre-pump arterial pressure, dynamic venous pressure, percentage of recirculation, and dose of dialysis) in conjunction with surveillance (normalized intra-access venous pressure and access flow). The annual rates of thrombosis, and primary, primary-assisted, and secondary patency were assessed. The incidence of significant stenosis and thrombosis was 57.4% (65/115) and 39.0% (45/115), respectively. Of all screening procedures, normalized intra-access venous pressure was the best predictor of significant stenosis (hazards ratio, 7.71; 95% confidence interval, 3.06-19.46). The annual rate of thrombosis fluctuated from 0 to 0.26 thromboses/patient/year, with an average rate of 0.14 thromboses/patient/year. Primary, primary-assisted, and secondary patency were 74%/79%/82%, 50%/60%/66%, and 23%/35%/37% at 1, 2, and 5 years, respectively. The implementation of a systematic graft follow-up protocol combined with monitoring and surveillance enabled early diagnosis and elective correction of significant stenosis, prolonged graft patency, and a low thrombosis rate.

Individualized Antithrombotic Therapy in Heartware HVAD Recipients.

There are no evidence-based guidelines for antithrombotic therapy in left ventricular assist device patients. We evaluated the efficacy of a multi-agent, test-guided protocol, which remained consistent throughout our use of the Heartware HVAD. Thrombelastography and platelet function analyzer (PFA)-100 guide antiplatelet titration. Goals are normal kaolin thrombelastography maximum amplitude and prolonged PFA-100. We analyzed incidence and rates of nonprocedural bleeding, stroke, and pump thrombosis for all 81 primary Heartware left ventricular assist devices implanted since 2011. For each event, we examined whether each test was within goal range. We also compared medication burden and dosage between patients with and without events. Pump thrombosis and hemorrhagic stroke each occurred in two patients (2.5%; 0.03 events/patient-year [EPPY]), and ischemic stroke in six (7.4%; 0.10 EPPY). Nonprocedural bleeding occurred 75 times in 34 patients (42%; 1.24 EPPY), primarily gastrointestinal (28%; 0.66 EPPY). Subtherapeutic international normalized ratio (INR) was the most common at thrombotic events; supratherapeutic partial thromboplastin time, international normalized ratio (INR), and PFA-adenosine diphosphate (ADP) were common at bleeding events. Medication burden and dosage were lower in patients with events than in stable patients. Protocol-guided antithrombotic therapy resulted in low rates of pump thrombosis and hemorrhagic stroke. Ischemic stroke and gastrointestinal bleeding rates were higher than in a comparable HVAD population. Optimization of our protocol to decrease its complexity and to reduce bleeding is underway.

Low Rate of Intrahospital Deep Venous Thrombosis in Acutely Ill Medical Patients: Results From the AURELIO Study

ObjectiveTo evaluate the effect of hospitalization on deep venous thrombosis (DVT) rate by the cumulative incidence of DVT in the proximal venous tract of the lower limbs at admission and discharge. MethodsThe AURELIO (rAte of venoUs thRombosis in acutEly iLl patIents hOspitalized in internal medicine wards) multicenter observational study was carried out in hospital-university internal medicine wards including consecutive acutely ill medical patients. Patients underwent compression ultrasonography (CUS) of proximal lower limb veins at admission and discharge. The occurrence of DVT was the primary end point of the study. ResultsAmong 1340 patients, 26 (1.9%; 95% CI, 1.3%-2.8%) had asymptomatic DVT at admission and were excluded. During the follow-up, 144 patients were excluded because of hospitalization less than 5 days. The remaining 1170 patients underwent a CUS at discharge. Two hundred fifty (21%) underwent prophylaxis with parenteral anticoagulants; the remaining 920 (79%) were not treated with anticoagulants. The mean length of hospitalization was 13±8 days. Compared with patients without prophylaxis, those treated with parenteral anticoagulants had a higher incidence of active cancer, heart and respiratory failure, pneumonia, renal failure, previous venous thromboembolism, reduced mobility, and elderly age. During the hospital stay, 3 patients with a negative CUS at admission experienced DVT in the proximal tract (0.025%, rate of 1 per 5017 patient-days); 2 of them were in prophylaxis with parenteral anticoagulants. ConclusionWe provide evidence that in the real world acutely ill medical patients display more than 90% (1.9%) asymptomatic DVT at admission, whereas the intrahospital DVT occurrence is very low. This suggests a novel diagnostic workup and a careful reanalysis of anticoagulant prophylaxis.

Ten-year experience of tricuspid valve replacement with the St. Jude medical valve

Bioprosthetic valves for tricuspid valve replacement (TVR) have become increasingly popular in recent years, but mechanical valves remain valuable, particularly for the patients who want to avoid reoperation for bioprostheses malfunction. The aim of this study was to review our 10-year experience in adult patients who underwent TVR with the St. Jude Medical (SJM) valve. From 2005 to 2015, 265 TVRs with SJM valves were performed at our institution. The mean age at operation was 44.1 ± 9.7 years, and 207 cases (78.1%) were female. The mean follow-up was 4.9 ± 2.7 years. Preoperative atrial fibrillation was present in 199 cases (75.1%) and ascites in 26 (9.8%). Of all cases, 88.7% were characterized as New York Heart Association class III or IV. The hospital mortality was 6.4%. There were 9 deaths (3.8%) during late follow-up. The overall survival rates were 89.2% ± 2.2% at 5 years and 86.6% ± 2.9% at 10 years. The linearized rates of valve thrombosis and bleeding events were 0.8%/patient-year and 1.5%/patient-year, respectively. Three cases (1.3%) were reoperated due to prosthetic valve thrombosis. There was no reoperation for sperivalvular leakage and structural failure. The freedom from reoperation was 98.6% ± 0.8% at 5 years and 98.6% ± 0.8% at 10 years. The SJM valve in the tricuspid position is a reliable mechanical prosthesis with a low rate of valve thrombosis and reoperation. It is a reasonable choice for the patients who require mechanical valve replacement in the tricuspid position.

Fluid Dynamics in the HeartMate 3: Influence of the Artificial Pulse Feature and Residual Cardiac Pulsation.

Ventricular assist devices (VADs), among which the HeartMate 3 (HM3) is the latest clinically approved representative, are often the therapy of choice for patients with end-stage heart failure. Despite advances in the prevention of pump thrombosis, rates of stroke and bleeding remain high. These complications are attributed to the flow field within the VAD, among other factors. One of the HM3's characteristic features is an artificial pulse that changes the rotor speed periodically by 4000 rpm, which is meant to reduce zones of recirculation and stasis. In this study, we investigated the effect of this speed modulation on the flow fields and stresses using high-resolution computational fluid dynamics. To this end, we compared Eulerian and Lagrangian features of the flow fields during constant pump operation, during operation with the artificial pulse feature, and with the effect of the residual native cardiac cycle. We observed good washout in all investigated situations, which may explain the low incidence rates of pump thrombosis. The artificial pulse had no additional benefit on scalar washout performance, but it induced rapid variations in the flow velocity and its gradients. This may be relevant for the removal of deposits in the pump. Overall, we found that viscous stresses in the HM3 were lower than in other current VADs. However, the artificial pulse substantially increased turbulence, and thereby also total stresses, which may contribute to clinically observed issues related to hemocompatibility.

Dual antiplatelet therapy after percutaneous left atrial appendage occlusion: single center experience with the Amplatzer Cardiac Plug

Background: Percutaneous left atrial appendage occlusion (LAAO) is an alternative to anticoagulation in atrial fibrillation patients at high bleeding risk. Dual antiplatelet therapy (DAPT) is generally recommended in the months following the procedure to prevent thrombotic complications. The aim of this study was to evaluate the safety and efficacy of DAPT after LAAO in a single-centre population of high bleeding risk patients.Methods: All patients who received DAPT after LAAO using the Amplatzer Cardiac Plug at Jessa Hospital (Hasselt, BE) between February 2011 and October 2016 were included. Patient characteristics, procedural outcome and clinical events (bleeding, stroke and adverse events) were prospectively followed. Changes in antithrombotic and/or anticoagulant regimens were assessed.Results: Thirty-nine patients (77 ± 7 years, 51% male, CHA2DS2-VASc 5(3–6), Hypertension, Abnormal Renal/Liver Function, Stroke, Bleeding History or Predisposition, Labile INR, Elderly, Drugs/Alcohol Concomitantly (HAS-BLED) 3(3–4)) were included. An initial strategy of one month DAPT (n = 2) was changed to six months DAPT (n = 37) after one thrombotic complication (device thrombosis) at 4.5 months. Post-procedural DAPT duration was 6.1 ± 3.7 months, after which aspirin monotherapy (62%), no antiplatelet/anticoagulant therapy (15%) or a tailored antithrombotic regimen was maintained. At mean follow-up of 21 ± 13 months, seven patients had died (18%), no strokes had occurred (0%) and nine bleedings of which four were major (10%). All major bleedings occurred within the first six months after the procedure during DAPT.Conclusion: Antithrombotic therapy after percutaneous LAAO is needed to prevent thrombotic complications, yet these impose bleeding complications in this high-risk population. Further efforts are needed to define the optimal duration of DAPT, aimed at reducing bleeding complications while maintaining a low thrombosis rate.

BCR-ABL Tyrosine Kinase Inhibitors: Which Mechanism(s) May Explain the Risk of Thrombosis?

Imatinib, the first-in-class BCR-ABL tyrosine kinase inhibitor (TKI), had been a revolution for the treatment of chronic myeloid leukemia (CML) and had greatly enhanced patient survival. Second- (dasatinib, nilotinib, and bosutinib) and third-generation (ponatinib) TKIs have been developed to be effective against BCR-ABL mutations making imatinib less effective. However, these treatments have been associated with arterial occlusive events. This review gathers clinical data and experiments about the pathophysiology of these arterial occlusive events with BCR-ABL TKIs. Imatinib is associated with very low rates of thrombosis, suggesting a potentially protecting cardiovascular effect of this treatment in patients with BCR-ABL CML. This protective effect might be mediated by decreased platelet secretion and activation, decreased leukocyte recruitment, and anti-inflammatory or antifibrotic effects. Clinical data have guided mechanistic studies toward alteration of platelet functions and atherosclerosis development, which might be secondary to metabolism impairment. Dasatinib, nilotinib, and ponatinib affect endothelial cells and might induce atherogenesis through increased vascular permeability. Nilotinib also impairs platelet functions and induces hyperglycemia and dyslipidemia that might contribute to atherosclerosis development. Description of the pathophysiology of arterial thrombotic events is necessary to implement risk minimization strategies.

Factors Associated with Contralateral Deep Venous Thrombosis after Iliocaval Venous Stenting

The majority of iliac venous obstructions occur on the left side, and endovascular therapy has become the first line treatment for this condition. A left common iliac venous stent will protrude into the inferior vena cava (IVC) to some extent, thereby covering the contralateral common iliac vein (CIV) outflow. This may increase the risk of thrombosis of the contralateral iliac vein. The aim of this paper was to determine the rate of, and factors associated with, contralateral lower limb venous thrombosis after stenting, and to evaluate the results of salvage revascularisation. A total of 376 patients (102 from UCH, Galway, Ireland, 2008–16, and 274 from, CHU Nord, Marseille, France, 2000–15) with symptomatic acute or chronic left iliocaval venous obstruction were retrospectively evaluated. Either duplex ultrasound scanning (DUS) or computed tomographic venography (CTV) was used for pre- and post-operative imaging. Data were collected from the PACS system (IMPAX, Agfa, BE) of the Radiology Department, UCH, Galway, and from the electronic medical records of Vascular Surgery department, CHU Nord, Marseille. The median age of stented patients was 46 (range 15–86 years), 80% were female (301/376). Following left CIV stent placement, 10 patients later presented with a right (contralateral) iliac deep venous thrombosis (DVT) resulting in a cumulative incidence of contralateral DVT of 4% according to Kaplan-Meier analysis. Acute DVT (P=.001), non-compliance with the prescribed 6 months anticoagulation (P = 0.05), pre-operative contralateral internal iliac vein (IIV) thrombosis (P = 0.001), and pre-existing IVC filter placement (P = 0.003) were all statistically significantly associated with contralateral DVT. All patients with symptomatic contralateral iliac DVT underwent clot removal in the acute phase. The primary patency of these limbs was 100% at 3 years. Stent placement across the iliocaval confluence from the left CIV is associated with a low but definite rate of contralateral iliac vein thrombosis. Acute DVT, pre-operative contralateral IIV thrombosis, pre-existing IVC filters, and anticoagulation non-compliance are significant risk factors.

Drug-Coated Balloon Treatment for Femoropopliteal Artery Disease: The IN.PACT Global Study De Novo In-Stent Restenosis Imaging Cohort

ObjectivesThis study sought to evaluate the safety and effectiveness of a paclitaxel-coated drug-coated balloon (DCB) for the treatment of patients with de novo in-stent restenosis (ISR). BackgroundTreatment of patients with ISR remains a challenge. Current strategies are plagued by high rates of recurrent restenosis and need for reintervention. The best intervention for ISR remains to be elucidated. MethodsThe IN.PACT Global study is an independently adjudicated multicenter, prospective, single-arm study that enrolled 1,535 subjects with symptomatic atherosclerotic disease of the superficial femoral and/or popliteal arteries, including de novo ISR lesions. Patients enrolled in the pre-specified ISR imaging cohort were evaluated for vessel patency and reintervention within the 12-month follow-up period. ResultsA total of 131 subjects with 149 ISR lesions were included for analysis. The mean age of the cohort was 67.8 years. Mean lesion length was 17.17 ± 10.47 cm, including 34.0% total occlusions and 59.1% calcified lesions. The 12-month Kaplan-Meier estimate of primary patency was 88.7%. The rate of clinically driven target lesion revascularization (CD TLR) at 12 months was 7.3%. The primary safety outcome, a composite of freedom from device- and procedure-related mortality through 30 days and freedom from major target limb amputation and CD TLR within 12 months, was 92.7%. There were no major target limb amputations, no deaths, and a low (0.8%) thrombosis rate. ConclusionsResults from the ISR imaging cohort demonstrate high patency and a low rate of CD TLR at 12 months. These data confirm the safety and effectiveness of the IN.PACT Admiral DCB (Medtronic, Dublin, Ireland) in complex femoropopliteal lesions, including this challenging subset.

Factors Associated with Contralateral Deep Venous Thrombosis after Iliocaval Venous Stenting

The majority of iliac venous obstructions occur on the left side, and endovascular therapy has become the first line treatment for this condition. A left common iliac venous stent will protrude into the inferior vena cava (IVC) to some extent, thereby covering the contralateral common iliac vein (CIV) outflow. This may increase the risk of thrombosis of the contralateral iliac vein. The aim of this paper was to determine the rate of, and factors associated with, contralateral lower limb venous thrombosis after stenting, and to evaluate the results of salvage revascularisation. A total of 376 patients (102 from UCH, Galway, Ireland, 2008-16, and 274 from, CHU Nord, Marseille, France, 2000-15) with symptomatic acute or chronic left iliocaval venous obstruction were retrospectively evaluated. Either duplex ultrasound scanning (DUS) or computed tomographic venography (CTV) was used for pre- and post-operative imaging. Data were collected from the PACS system (IMPAX, Agfa, BE) of the Radiology Department, UCH, Galway, and from the electronic medical records of Vascular Surgery department, CHU Nord, Marseille. The median age of stented patients was 46 (range 15-86 years), 80% were female (301/376). Following left CIV stent placement, 10 patients later presented with a right (contralateral) iliac deep venous thrombosis (DVT) resulting in a cumulative incidence of contralateral DVT of 4% according to Kaplan-Meier analysis. Acute DVT (p=.001), non-compliance with the prescribed 6 months anticoagulation (p=0.05), pre-operative contralateral internal iliac vein (IIV) thrombosis (p=0.001), and pre-existing IVC filter placement (p=0.003) were all statistically significantly associated with contralateral DVT. All patients with symptomatic contralateral iliac DVT underwent clot removal in the acute phase. The primary patency of these limbs was 100% at 3 years. Stent placement across the iliocaval confluence from the left CIV is associated with a low but definite rate of contralateral iliac vein thrombosis. Acute DVT, pre-operative contralateral IIV thrombosis, pre-existing IVC filters, and anticoagulation non-compliance are significant risk factors.

Thromboembolic Events Following Splenectomy: Risk Factors, Prevention, Management and Outcomes.

Thromboembolic events following splenectomy are not uncommon. However, the role of thromboprophylaxis and risk factors for thrombosis, as well as the clinical course and outcomes, are not well characterized. A retrospective review of individuals who underwent splenectomy between January 2006 and December 2015 in two university hospitals. Overall, 297 patients underwent splenectomy [open splenectomy (n=199), laparoscopic splenectomy (n=98)]. Mechanical (thigh-length pneumatic compression stockings) and pharmacologic thromboprophylaxis (40mg enoxaparin daily, starting 12h after surgery until discharge) was provided for all patients. One hundred and sixteen patients (39%) also received an extended thromboprophylaxis course of enoxaparin for 2-4weeks after discharge. Twenty-three patients (7.7%) experienced thrombotic complications following splenectomy, including 16 cases (5.4%) of portal-splenic mesenteric venous thrombosis (PSMVT), 5 (1.7%) pulmonary embolism and 2 (0.7%) deep vein thrombosis. Longer operative time (mean operative time of 405 vs. 273min, P=0.03) was independently associated with PSMVT. Post-splenectomy thrombocytosis was not associated with thrombosis (P=0.41). The overall thrombosis rate was significantly lower in patients who received an extended thromboprophylaxis course following splenectomy (3.4 vs. 10.5%, P=0.02). Complete resolution of thrombosis was observed in most cases (n=20, 87.0%), with no recurrent thrombosis during a mean follow-up of 38±25months. Thromboembolic complications, mainly PSMVT, are common following splenectomy. Longer operative time was associated with thrombosis. Significantly lower rates of thrombosis were found in patients who received an extended thromboprophylaxis course.