Risk Factors For Thrombus Formation Research Articles

Abstract 16199: Postsurgical Takotsubos Complicated by Clot Burden in the Setting of Heterozygous Prothrombin Gene Mutation

Introduction: Postsurgical Takotsubo cardiomyopathy (TCM) is associated with acute stress secondary to catecholamine release causing reversible left ventricular (LV) failure. We present a diagnostically challenging presentation of postsurgical TCM with underlying prothrombin gene mutation. Case Presentation: A 53 year old female underwent laparoscopic hysterectomy 2 days prior to presentation with chest pain and shortness of breath. Vitals were unremarkable, labs showed elevated troponin and EKG consistent with NSTEMI. CTA chest demonstrated significant clot burden to the ascending and descending aorta. Echocardiogram revealed a reduced ejection fraction (EF) of 25-30% with apical ballooning and thrombus. She was admitted on heparin drip and completed an infusion of eptifibatide for 24 hours. Repeat CTA chest demonstrated mildly reduced clot burden. Left heart catheterization (LHC) was precluded due to aortic arch clot. Coronary CTA revealed no CAD with a calcium score of 0. Coagulopathy workup showed heterozygous prothrombin G20210A variant. She was discharged on warfarin. Repeat echocardiography 1 month later showed improved EF to 40-45%. Discussion: TCM accounts for 1-3% of cases of acute coronary syndromes (ACS) and affects women at a rate of 90%. Studies have shown that TCM with apical ballooning is minimally associated with LV thrombus . The presence of heterozygous prothrombin gene mutation increases risk of clot formation by 2 to 3 times. Surgery can cause this risk to dramatically increase. Coronary CTA was the best noninvasive approach to make the diagnosis as the risk of LHC was too great given the anatomic challenge of the aortic arch clot. We advocate for hypercoagulable workups to inform management of anticoagulation in patients with clotting events without known risk factors for thrombus formation.

Aging Is Associated With Organ-Specific Alterations in the Level and Expression Pattern of von Willebrand Factor.

VWF (von Willebrand factor) is an endothelial-specific procoagulant protein with a major role in thrombosis. Aging is associated with increased circulating levels of VWF, which presents a risk factor for thrombus formation. Circulating plasma, cellular protein, and mRNA levels of VWF were determined and compared in young and aged mice. Major organs were subjected to immunofluorescence analyses to determine the vascular pattern of VWF expression and the presence of platelet aggregates. An in vitro model of aging, using extended culture time of endothelial cells, was used to explore the mechanism of age-associated increased VWF levels. Increased circulating plasma levels of VWF with elevated levels of larger multimers, indicative of VWF functional activity, were observed in aged mice. VWF mRNA and cellular protein levels were significantly increased in the brains, lungs, and livers but not in the kidneys and hearts of aged mice. Higher proportion of small vessels in brains, lungs, and livers of aged mice exhibited VWF expression compared with young, and this was concomitant with increased platelet aggregate formation. Prolonged culture of endothelial cells resulted in increased cell senescence that correlated with increased VWF expression; VWF expression was specifically detected in senescent cultured endothelial cells and abolished in response to p53 knockdown. A significantly higher proportion of VWF expressing endothelial cells in vivo exhibited senescence markers SA-β-Gal (senescence-associated β-galactosidase) and p53 in aged mouse brains compared with that of the young. Aging elicits a heterogenic response in endothelial cells with regard to VWF expression, leading to organ-specific increase in VWF levels and alterations in vascular tree pattern of expression. This is concomitant with increased platelet aggregate formation. The age-associated increase in VWF expression may be modulated through the process of cell senescence, and p53 transcription factor contributes to its regulation.

Acute bilateral renal infarction after left upper pulmonary lobectomy: a case report

BackgroundLeft upper lobectomy (LUL) is considered a risk factor for thrombus formation in the pulmonary vein stump compared with other lobectomies, and it occurs in 11.7–13.5% of cases. Although cerebral infarction after LUL has been reported in many articles, reports of bilateral renal infarction after lobectomy are rare.Case presentationA 70-year-old male patient was admitted to our hospital with a diagnosis of lung cancer. The nodule’s diameter was 2.5 cm on computed tomography, and it was diagnosed as a non-small cell lung carcinoma by a bronchoscopic biopsy. The clinical stage was cT1c N0M0 (c-stageIA3). The patient underwent thoracoscopic LUL and systemic lymph node dissection. No complications were observed during the operation, and the immediate postoperative period was uneventful until postoperative day 3. On postoperative day 4, he experienced fever, abdominal pain, and nausea, which spontaneously resolved. Laboratory data showed an elevated white blood cell count, and elevated serum lactate dehydrogenase and creatinine concentrations. Contrast-enhanced computed tomography from the thorax to the pelvic cavity showed a partial defect of the bilateral kidneys. We diagnosed the patient with bilateral renal infarction. ConclusionsBilateral renal infarction after lobectomy is a rare and serious condition, which should be diagnosed as early as possible. Since all cases of reported renal infarctions occurred after LUL, special attention should be paid to postoperative management after performing LUL.

Acute arterial thrombosis in anticoagulated patient for acute pulmonary thromboembolism

Acute limb ischemia is rare in patients with venous thromboembolism who already receive anticoagulation treatment. Inflammation is a risk factor for thrombus formation. Patients with active ulcerative colitis, especially at the time of exacerbation, are more prone to thromboembolism, both venous and arterial. The risk for thrombosis is 18% higher, with a higher risk of bleeding. To date, there is no contraindication to any anticoagulant drug in patients with ulcerative colitis. We represent a case of a 73 year - old woman with ulcerative colitis exacerbation, hospitalized initially for pulmonary thromboembolism, that developed acute arterial thrombosis when switched on a novel oral anticoagulant.

The risk factors of thrombus formation and the effect of catheter ablation on repetitive thrombus formation in patients with atrial fibrillation: a single center retrospective study in China

BackgroundAtrial fibrillation (AF) predisposes patients to the formation of atrial thrombi. The CHA2DS2-VASc score does not include all risk factors for atrial thrombosis. The present study is designed to explore the influencing factors of thrombus formation in patients with AF and to investigate the effect of catheter ablation (CA) on recurrent thrombosis in patients with a history of intracardiac thrombus.Methods(1) This study consisted of 1726 patients that underwent CA, among which 58 patients had a history of intracardiac thrombus prior to CA. The risk factors for thrombus formation were explored by comparing the baseline clinical characteristics of patients with and without atrial thrombus. (2) The left atrial appendage flow velocity (LAAFV) in patients with a history of intracardiac thrombus who were willing to undergo transesophageal echocardiography (TEE) at the latest follow-up were examined, and comparisons of the LAAFV was made before and after CA.ResultsThe median follow-up period is 13 months. Persistent AF was found to be the only independent risk factor affecting the formation of atrial thrombus among the investigated factors (OR 3.152; 95%CI 1.806–5.500; p < 0.001). Twenty-seven patients agreed to undergo TEE during follow-up, no clinical ischemic stroke events were recorded, no recurrent intracardiac thrombus formation was detected in patients, 15 patients maintained sinus rhythm (55.6%) during follow-up; successful CA significantly increased LAAFV (difference between latest evaluation prior to CA 17.46 ± 14.81 cm/s, p < 0.001).ConclusionsPersistent AF is the only independent risk factor for thrombus formation. Successful CA may improve the LAAFV and thereby decrease the risk of intracardiac thrombus formation.

587 LEFT ATRIAL APPENDAGE OCCLUSION: A REAL SOLUTION TO CARDIOEMBOLIC RISK OF ATRIAL FIBRILLATION?

Abstract 82-year-old woman comes to our clinical observation for worsening exertional dyspnea, with ECG evidence of atrial fibrillation (AF) with high ventricular response. Past medical history: previous right breast carcinoma treated in 1998 with quadrantectomy, radiotherapy and hormone therapy. Previous ischemic transitory attack. Hypertension. Dyslipidemia. The patient reports the first episode of paroxysmal AF in 2016, for which anticoagulant therapy with new oral anticoagulants NOACs was started for CHA2DS2VASc=6. During anticoagulant therapy episode of ocular haemorrhage for which the patient discontinued therapy with NOACs and used low-molecular-weight heparin LMWH "as needed" in the course of arrhythmic relapses. In July and August 2019 relapses of symptomatic paroxysmal AF. Multiple attempts to take different anticoagulants (Rivaroxaban, Edoxaban) poorly tolerated. The patient undergoes catheter ablation by isolation of the pulmonary veins (considered first line according to ESC guidelines for the control of symptoms in patients with paroxysmal AF) and percutaneous left atrial appendage occlusion (LAAO), with indication of anticoagulation therapy for at least 4 weeks after the procedure (Apixaban 2.5 mg bid, reduced dose due to the presence of age&amp;gt;80 years and weight&amp;lt;60 kg). At the entrance to our hospital, an ECG is performed with a finding of total arrhythmia from AF with a high ventricular response (HR 130 bpm), conducted with left bundle branch block (LBBB); cardiac echo-Doppler ultrasound is performed with a slight reduction in left ventricular systolic function (EF 45%), second degree diastolic dysfunction with increased filling pressures, moderate mitral valve insufficiency, severe left atrial dilatation (LAVi 125 ml/m2), moderate tricuspid valve insufficiency with moderate pulmonary arterial hypertension (PAPS 55 mmHg), right atrial dilatation, circumferential pericardial detachment, dilated inferior vena cava hyporeactive with breath acts. At blood tests: BNP 1022 pg/ml, sodium 145 mmol/l, potassium 3.5 mmol/l, creatinine 1.17 mg/dl with eGFR 43 ml/min/1.73mq. Rate control therapy with ß-blockers and Digoxin and diuretic therapy with Furosemide and Canrenone is set, with improvement of symptoms and clinical conditions. Anticoagulant therapy with LMWH is also undertaken but the patient shows poor adherence. After home discharge, the patient goes back to the emergency room for dyspnea. Further cardiac echo-Doppler ultrasound is performed with evidence of thrombotic formation in the left atrium of the size of 30×25 mm. Therapeutic dosage LMWH therapy is started with subsequent Warfarin embrication according to INR, obtaining complete resolution of the thrombotic formation. A systematic review of device-related thrombosis (DRT) after left atrial appendage occlusion (LAAO) proved that the overall incidence of DRT was 3.9% and the median time from procedure to diagnosis of DRT was 1.5 months. According to currently reported cases, most DRTs occur within one year after LAAO. This particular clinical case of DRT three years after LAAO underlines the importance of accurate assessment of the patient's risk profile: LAAO is a valid alternative to anticoagulant therapy in patients at high risk of bleeding but with low embolic risk profile. It's known that high CHA2DS2VASc values ​​and reduced cardiac function are recognized risk factors for thrombus formation, such as patient compliance with antithrombotic therapy. Surely additional studies are needed to determine if the current practice of antithrombotic regimens and duration after LAAO is sufficient.

CORRELATION OF CELL SENESCENCE WITH THE AGE-ASSOCIATED INCREASE IN VWF EXPRESSION

Von Willebrand factor (VWF) is an endothelial-specific pro-coagulant protein with a major role in thrombosis. It mediates the primary step in thrombogenesis, which is platelet adhesion to the endothelium/sub-endothelium surfaces. Increased VWF level is a significant risk factor for thrombus formation and has been associated with aging. However, the mechanism underlying this age-related increase in VWF remains unknown. We explored the molecular mechanism and functional consequences of age-related upregulation of VWF.

Determining the role of von Willebrand factor in thrombotic post transplantation complications using ex vivo lung perfusion system

Background and Aims : A major complication of lung transplantation is thrombosis, which may lead to allograft failure. Increased production of procoagulant molecules, such as von Willebrand factor (VWF), is a significant risk factor for thrombus formation. VWF is a pro-coagulant glycoprotein expressed only in endothelial cells and megakaryocytes, which mediates adhesion of platelets to the endothelium/sub-endothelium. External stimuli, including hypoxia can upregulate VWF. Since during organ-transplantation donor organs are under hypoxic conditions, we explored whether this may lead to alterations in VWF expression, and whether ex vivo lung perfusion (EVLP) as an innovative method for organ preservation prior transplantation can moderate the effect of VWF upregulation and its thrombogenic consequences.

Implanon and Pulmonary EmbolismAny Association?

Implanon is a single rod contraceptive implant, it is one of the most reliable birth control methods, highly effective with rapid onset of action and an equally rapid return of fertility once removed. Thromboembolic events are established adverse events of hormonal contraceptives; however, few cases of thromboembolic complications of implanon have been reported in the literature. A 39 year old woman, with no known risk factors for thrombus formation and no past history of thromboembolic events presented with difficulty with breathing, cough, hemoptysis, chest pain and an episode of syncopal attack. Further evaluation revealed elevated D dimer, sinus tachycardia on (ECG) and computerized tomography pulmonary angiogram (CTPA) finding of pulmonary embolism. She had implanon inserted for contraception 2 months before the event. Initiation of prompt management with anticoagulant and discontinuation of implanon led to a favourable patient outcome. In conclusion, pulmonary embolism is a possible though uncommon adverse event associated with implanon contraceptive. Therefore, women of reproductive age group requiring contraceptives should be risk stratified with the aim of identifying those with increased risk of this side effect. They should be properly guided and counseled on the appropriate choice of safe and effective contraceptive method. In addition, women on hormonal contraceptive methods (including implanon) presenting with symptoms suggestive of thromboembolic events should be promptly evaluated and treated to avoid high fatality associated with this condition.

An In Vivo Observational Histological Study of Peripheral Arterial Damage in Patients with Acute Limb Ischemia in SARS-CoV-2 Infection.

Thromboembolic events, such as acute limb ischemia, were reported worldwide in patients with COVID-19, suggesting that SARS-CoV-2 infection acts like a redoubtable prothrombotic factor in these patients. The aim of the study was to summarize the histopathological changes found in the arterial wall, intraarterial thrombus, and adjacent skeletal muscles. Considering the lack of evidence from in vivo studies, we performed observational histological research of peripheral arterial damage in patients with acute limb ischemia and SARS-CoV-2 infection. We investigated 22 patients with acute limb ischemia and SARS and harvested histopathological samples from those who agreed to this procedure. We performed histologic tissue harvesting during the revascularization procedure from the thrombosed area of the common femoral artery. Morphologic analysis was made on the hematoxylin-eosin (HE) stain. Special stains were also used—Elastica van Gieson (EvG) and Alcian Blue—Periodic Acid—Schiff (AB-PAS) and primary antibodies—CD45 and CD61. Our patients had significant risk factors for thrombus formation, since all of them had arterial hypertension, 81% had dyslipidemia, 73% were obese, 63% suffered from diabetes mellitus, and 45% were active smokers. The histological findings using immunohistochemistry (CD45 and CD68 reactions) or special and usual stains underlined the mechanism for ischemia production in SARS-CoV-2 patients. The main histological findings in our study were endothelial destruction and inflammation that were found in all analyzed structures.

Risk Factors for Thrombus Formation at Stage 2 Palliation and Its Effect on Long-Term Outcome in Patients With Univentricular Heart

Thrombus formation is a feared complication following bidirectional cavopulmonary shunt (BCPS). We aimed to investigate the effect of thrombus formation on outcome. BCPS was performed in 525 patients at our center between 1998 and 2018. The impacts of thrombus formation on survival and probability of Fontan completion were analyzed, and risk factors for thrombus formation were examined. Thrombus formation occurred in 30 patients (5.7%). Compared with the remaining 495 patients, there was no significant difference in the median age at BCPS (4.9 vs 4.7 months; P = 0.587). However, unbalanced atrioventricular septal defects (17 vs 5%; P = 0.008) and preoperative ventricular dysfunction (23.3 vs 8%; P = 0.004) were more frequent in patients who developed a thrombus. Thrombolytic therapy was performed in all patients and surgical thrombus removal was required in 13 patients. In-hospital mortality was higher in patients with thrombus (30.0 vs 2.2%; P < 0.001). Of 505 hospital survivors, an estimated survival at 1 year after hospital discharge following BCPS was 84.4% (95% CI, 76.1-92.7%) in patients with thrombus and 96.8% (95% CI, 96.0-97.6%) in those without (P < 0.001). Cumulative incidence of Fontan completion at 3 years after BCPS was 52.8% (95% CI, 30.3-75.2%) in patients with thrombus and 90.1% (95% CI, 87.2-92.9%) in those without (P = 0.004). Higher left atrial pressure (OR = 1.165; P = 0.029) and longer cardiopulmonary bypass time (OR = 1.013, P = 0.001) at BCPS were independent risk factors for thrombus formation after BCPS. Thrombus formation after BCPS poses a significant risk for survival and Fontan completion. Preoperative higher left atrial pressure and longer cardiopulmonary bypass time are significant risk factors.

Simulation Study on Blood Flow Mechanism of Vein in Existence of Different Thrombus Size

Blood velocity is expected to be as a parameter for detecting abnormality of blood such as the existence of thrombus. Proper blood flow in veins is important to ensure effective return of deoxygenated blood to the heart. However, it is much challenging to recognize the vessel condition due to the inability to visualize the thrombus presence in the vessel. The presence of noise in the image obtained from ultrasound scanning is one of the obstructions in recognizing it. Considering the difficulty, this study aims to assess the velocity and vorticity at the vein valve region using Computational Fluid Dynamics (CFD) method. The velocity of blood and the size of valve orifice are considered important parameters in designing the vein since the stenosis and irregularities of velocity in blood vessels are known as the risk factors for thrombus formation. From the simulation, the velocity contour plot of the blood flow can be visualized clearly. The blood distribution was presented using velocity profile while the fluid particles movement was shown by the velocity vector. The low blood velocity clearly shows the low velocity region which reside at the cusps area and at the beginning of the valve leaflets. Therefore, the present study is able to visualize and evaluate the probable location of thrombus development in the blood vessel.

Incidence of Catheter Related Thrombosis in Chronic Kidney Disease Patients Admitted in Intensive Care Unit and their Outcome: An Observational Study

Introduction: Central Venous Catheter (CVC) insertion is a commonly performed procedure in the Intensive Care Unit (ICU) to facilitate administration of intravenous fluids and drugs, Central Venous Pressure (CVP) measurement, and Haemodialysis (HD). It is associated with various complications including thrombus formation. Aim:To determine the incidence of thrombus, its extent, associated risk factors and outcomes, in the triple lumen HD catheter inserted in Internal Jugular Vein (IJV) in Chronic Kidney Disease (CKD) patients admitted in the ICU. Materials and Methods: This was a prospective observational study including a total of 100 patients (63 males and 37 females) of CKD, who required HD in the ICU at Pacific Institute of Medical Sciences (PIMS), Girwa, Udaipur, Rajasthan, India. The study was done from March 2017 to Mrach 2018. After admission in ICU, Arterial Blood Gas (ABG) was performed and Electrocardiography (ECG), Noninvasive Blood Pressure (NIBP), Oxygen Saturation (SpO2) monitoring was done. A triple lumen HD catheter was inserted in the IJV under all aseptic precautions. After two weeks of insertion, a colour doppler Ultrasonography (USG) neck was performed to see the presence, size and extent of thrombus in the CVC. All the pre and postprocedural demographic and clinical data of relevant investigations, past history, risk factors and complications were compiled together and compared in Microsoft excel sheet and Statistical Package for the Social Sciences (SPSS)softwares for relevant results. Results: The study found that 30% were having thrombus after two weeks of HD catheter in the IJV and most commonly detected in the diabetic patients with CKD 10 (33.33%), followed by hypertension two (6.66%), cerebro-vascular accidents one(3.33%), chronic liver diseases one (3.33%) and no thrombus was detected in patients suffering from ischemic heart diseases. The most common risk factor for thrombus formation was chronic smoking 12(40%), followed by bedridden patients two(6.66%), and chronic alcoholic patients 2(6.66%). Conclusion: This study found that early catheter-related thrombus was common in male patients with diagnosed diabetes mellitus and chronic smoking is the most common associated risk factor.

Abstract 17422: Transcatheter Mitral Valve Thrombosis: A Case Report and Literature Review

Background: Trans-catheter mitral valve replacement (TMVR) is an exciting alternative therapy for complex patients with mitral valve disease. The experience with TMVR is new and there is a lot yet to discover about their durability, long-term outcomes, and complications including, mitral transcatheter heart valve (THV) thrombosis. Many factors have been speculated to be associated with the increased risk of THV thrombosis. Here, we report a case of mitral THV thrombosis then discuss published data on the subject. Case presentation: A 72-year-old woman who underwent TMVR for severe mitral regurgitation with mitral annular calcification. She was discharged on aspirin and clopidogrel for thromboprophylaxis. She presented after 30 days with symptomatic heart failure. Her transesophageal echocardiogram showed increased mean trans-mitral gradient with severe subvalvular thickening with immobile neo-anterior leaflet. She was subsequently started on a heparin drip with bridge to warfarin with international normalized ratio goal of 2.5 to 3.5. Discussion: Since most patients undergoing TMVR are within a high-risk population, caution should be implemented to minimize complications, valve dysfunction, and failure. We reviewed 42 TMVR papers with total of 1484 patients including 60 with mitral THV thrombosis. We discussed the most common strategies used for mitral THV thromboprophylaxis and treatment. Conclusion: Given current evidence, post-TMVR anticoagulation should be considered for at least 3 months, especially in those without significant bleeding risk. Longer anti-coagulation therapy should be considered for patients with multiple risk factors for thrombus formation. Additionally, systematic active screening with close clinical follow up help promptly identify those with subclinical THV thrombosis or need longer anti-coagulation therapy.

Evaluation of Central Line Thrombosis in Children with Heart Failure on Continuous Infusion Milrinone

Milrinone is utilized for hemodynamic support in heart failure (HF) patients. Due to reduced cardiac output and systemic blood flow, patients with HF are at increased risk of thrombosis. Central venous catheter (CVC) placement compounds this risk. The aim of this study was to determine the incidence of thrombosis, identify thrombosis risk factors, and determine the impact of anticoagulation in pediatric patients receiving continuous milrinone via CVC at the Medical University of South Carolina. This retrospective study evaluated HF patients less than 18 years of age receiving continuous milrinone infusion via CVC for greater than or equal to 14 days between July 2014 and July 2019. Patients were evaluated based on anticoagulation (AC) status: therapeutic, prophylactic, or none (NAC). The primary outcome measure was the incidence of thrombosis. Possible risk factors for thrombus formation analyzed included age, pathogenesis of heart failure, ventricular assist device (VAD) use, duration of milrinone, and type of CVC. Blood product, factor VII, and prothrombin complex concentrate (PCC) utilization during VAD placement and transplant were analyzed as safety endpoints. A total of 35 patients were included - 16 patients receiving AC and 19 with NAC. There was no difference in thrombus formation between the AC and NAC groups [5 vs. 6; P = .49]. Of patients on prophylactic AC, 50% (n = 4) experienced a thrombus, compared to 25% (n = 12) of patients on therapeutic AC. Patients with CVC in place for greater than 300 days had an incidence of thrombosis of 83% (n = 6). Those receiving therapeutic AC used more PCC and Factor VII than the NAC group during transplant [17.37 units/kg vs. 0, P = .004, 74.74 mcg/kg vs. 18 mcg/kg, P = .025]. Those on therapeutic AC utilized more blood products than patients on prophylactic AC during both VAD placement and transplant (61.5 mL/kg vs. 3.5 mL/kg, P = .003) and NAC patients (61.5 mL/kg vs 24.6 mL/kg, P = .046). Incidence of thrombosis was similar among anticoagulated and non-anticoagulated patients who were on continuous infusion milrinone. Higher total CVC days increased the risk of thrombosis. Prophylactic anticoagulation had a limited effect on thrombus formation, but did not increase blood product use during VAD and transplant procedures as compared to therapeutic anticoagulation.

Relationship between spontaneous echo contrast and hematological markers in patients with rheumatic mitral stenosis

Systemic thromboembolism is a serious morbidity and mortality cause for patients with rheumatic mitral stenosis (MS). Previously conducted researches showed that spontaneous echo contrast (SEC) found in the left atrium can constitute a risk factor for thrombus formation. The aim of this study is to evaluate the role of echocardiographic and hematologic parameters in anticipating the presence of SEC in the left atrium of patients with severe RMS. This retrospective study includes all patients who were diagnosed with severe and very severe (MS) between 2014 and 2016. They were then divided in two groups depending on SEC presence. There were 29 patients (30%) in the SEC positive group (group I) and 71patients (70%) in the SEC negative group (group II). A CRP greater than 10 was found in 59% of patients with SEC, versus 21% in the second group. There was no significant difference in blood counts between the two groups. An ACFA was scored in 71% in first-group patients, versus 34% in the second group. Patients with SEC, had a left atrium dilated in 82% versus 37% in the second group. Also, MS was very tight in this population. In addition to the very tight nature of the MR, the volume of left atrium and heart rhythm, CRP was found to be related to left atrial SEC presence in patients with severe MS.

Large mobile left ventricular thrombus in a patient with dilated cardiomyopathy: a case report and review of literature

Dilated cardiomyopathy (DCMP) and the resultant left ventricular (LV) dysfunction are risk factors for thrombus formation in the heart. Once formed, depending on their size, location, and mobility, LV thrombi have the tendency to embolise, sometimes with dire consequences. Early detection and treatment are important to reduce thromboembolic events and in resolution of LV thrombus. Two-dimensional (2D) echocardiography is the most commonly used technique for the diagnosis and follow-up of such cases. Here, we present a case of 30 years old female with DCMP with congestive heart failure (CHF) who developed a large mobile LV thrombus and was managed on anticoagulants to prevent distal embolisation. This case highlights that LV thrombi can even occur in patients in sinus rhythm who have reduced LV contractility.

Thromboprophylaxis in Head and Neck Microvascular Reconstruction.

Head and neck patients undergoing microvascular reconstruction are at high risk for thromboembolism. While the prevention of thromboembolism has become an essential aspect of care, within the field of microsurgery, concern for anastomotic complications have hindered the creation of an accepted regimen. The aim of this review was to evaluate the risks and benefits of prophylactic agents for thromboprophylaxis. A literature search was conducted in MEDLINE, Cochrane Library, and PubMed/NCBI databases. Articles discussing thromboprophylaxis in otolaryngology, head and neck surgery, or microvascular reconstruction were considered in the review from the past 30 years. The majority of patients undergoing microvascular surgery have multiple risk factors for thrombus formation. Several consensus guidelines exist for the prophylaxis in patients who are critically ill, undergoing surgery, or with malignancy. Significant evidence supports the routine use of mechanical means, such as early mobilization and pneumatic compression along with subcutaneous heparin. Low-molecular-weight heparin is also frequently utilized, although results are largely divided. Data on aspirin remain equivocal. Studies on microvascular failure and flap loss have demonstrated little to no association with chemoprophylaxis. The evidence for postoperative thromboprophylaxis regimens in patients undergoing head and neck free tissue transfer is variable. Multiple studies have supported the use of unfractionated heparin or low-molecular-weight heparin. There appears to be an expert consensus for the combined use of mechanical prophylactic methods and chemical prophylaxis. Prospective randomized trials are required to validate the most effective combination of chemoprophylaxis agents.

Deaths Due to Pulmonary Embolism: 2 Case Reports

Pulmonary embolism (PE) is a major cause for morbidity and mortality. Following trauma to lower extremities, thrombus formation is a well-know entity, and one needs to foresee the possibility of embolism and eventual death. It is imperative and the onus solely rests on the treating doctor to weigh the risk factors for thrombus formation like age, sex, obesity, fracture, and immobilization and take necessary precautions to prevent pulmonary embolization. Two such cases with fractures of lower limb bones, where the deceased were middle aged, obese and immobilized for a period of time, died following muscular activity and autopsy revealed PE.

Acidosis induced by carbon dioxide insufflation decreases heparin potency: a risk factor for thrombus formation.

Since the introduction of CO2 insufflation during open heart surgery in our hospital, we incidentally observed thrombus formation in the dissected heart, in the pericardium and in the cardiotomy reservoir of the cardiopulmonary bypass system. Furthermore, we measured very high levels of pCO2, causing severe acidosis, in stagnant blood in the pericardium and cardiotomy reservoir. In this in vitro study, we assessed the influence of acidosis and hypothermia on heparin potency and thrombin formation. We assessed heparin potency in function of pH (pH 5.0-7.4) and temperature (24-37°C) by comparing the activated partial thromboplastin time in platelet-poor plasma between samples with and without unfractionated heparin. We measured thrombin formation in platelet-poor plasma by means of fluorescent, calibrated, automated thrombography in function of pH (pH 5.0-7.4) and temperature (24-37°C). The parameters of interest were the endogenous thrombin potential and the peak amount of thrombin generation. The major finding of this study is the significant decrease in the efficiency of unfractionated heparin in delaying thrombus formation at acidotic (pH 5.0-7.0) conditions (p=0.034-0.05). Furthermore, we found that thrombin formation is significantly increased at hypothermic (24-34°C) conditions (p=<0.001-0.01). Based on the results of our in-vitro study, we conclude that acidosis may lead to a decreased heparin potency. Acidosis, as induced by CO2 insufflation, may predispose patients to incidental thrombus formation in stagnant blood in the open thorax and in the cardiotomy reservoir. Hypothermia might further increase this risk. Therefore, we recommend reconsidering the potential advantages and disadvantages of using CO2 insufflation during cardiopulmonary bypass.