Resolution of Occlusive Carotid Artery Thrombus Treated with Anticoagulation as Demonstrated on Duplex Ultrasonography.

BACKGROUND AND PURPOSE: While the majority of cerebral ischemic events due to carotid occlusive disease result from atherosclerotic plaque rupture, intraluminal carotid artery thrombus occasionally occurs in patients without preexisting carotid atherosclerosis. Identification of nonatherosclerotic thrombus as the cause of the carotid occlusive disease can obviate the need for an interventional procedure, and resolution of thrombus can be monitored with B-mode duplex ultrasonography. METHODS: We reviewed 3 patients treated on The Mount Sinai Hospital Stroke Unit with anticoagulation for nonatherosclerotic carotid thrombi and followed with serial Doppler ultrasonogrpahy for resolution of thrombus. RESULTS: Occlusive carotid thrombus was successfully treated in all 3 patients with systemic anticoagulation. B-mode duplex ultrasonography allowed for demonstration of resolving thrombus. CONCLUSION: Differentiation between a stenotic plaque and occlusive thrombus can be achieved by ultrasonographic analysis of thrombus morphology, attachment site potential, and characteristics of a resolving thrombus. Systemic anticoagulation can safely and effectively eliminate the risk for future embolization and complete occlusion of the carotid artery in patients who present with transient ischemic events or completed infarcts of small size

Potentiation of thrombus instability: a contributory mechanism to the effectiveness of antithrombotic medications

© The Author(s) 2018The stability of an arterial thrombus, determined by its structure and ability to resist endogenous fibrinolysis, is a major determinant of the extent of infarction that results from coronary or cerebrovascular thrombosis. There is ample evidence from both laboratory and clinical studies to suggest that in addition to inhibiting platelet aggregation, antithrombotic medications have shear-dependent effects, potentiating thrombus fragility and/or enhancing endogenous fibrinolysis. Such shear-dependent effects, potentiating the fragility of the growing thrombus and/or enhancing endogenous thrombolytic activity, likely contribute to the clinical effectiveness of such medications. It is not clear how much these effects relate to the measured inhibition of platelet aggregation in response to specific agonists. These effects are observable only with techniques that subject the growing thrombus to arterial flow and shear conditions. The effects of antithrombotic medications on thrombus stability and ways of assessing this are reviewed herein, and it is proposed that thrombus stability could become a new target for pharmacological intervention.Peer reviewedFinal Published versio

Prognostic Outcomes and Risk Factors for Patients with Renal Cell Carcinoma and Venous Tumor Thrombus after Radical Nephrectomy and Thrombectomy: The Prognostic Significance of Venous Tumor Thrombus Level.

IntroductionTo evaluate the prognostic outcomes and risk factors for renal cell carcinoma (RCC) patients with venous tumor thrombus in China.Materials and methodsWe reviewed the clinical information of 169 patients who underwent radical nephrectomy and thrombectomy. Overall and cancer-specific survival rates were analyzed. Univariate and multivariate analyses were used to investigate the potential prognostic factors.ResultsThe median survival time was 63 months. The five-year overall survival and cancer-specific survival rate were 53.6% and 54.4% for all patients. For all patients, significant survival difference was only observed between early (below hepatic vein) and advanced (above hepatic vein) tumor thrombus. However, significant differences existed between both RV/IVC and early/advanced tumor thrombus groups in N0M0 patients. Multivariate analysis demonstrated that higher tumor thrombus level (p = 0.016, RR = 1.58), N (p = 0.013, RR = 2.60), and M (p < 0.001, RR = 4.14) stages and adrenal gland invasion (p = 0.001, RR = 4.91) were the most significant negative prognostic predictors.ConclusionsIn this study, we reported most cases of RCC patients with venous extension in China. We proved that patients with RCC and venous tumor thrombus may have relative promising long-term survival rate, especially those with early tumor thrombus

In Vivo Measurement of Blood Clot Mechanics from Computational Fluid Dynamics based on Intravital Microscopy Images

Ischemia leading to heart attacks and strokes is the major cause of deaths in the world. Whether an occlusion occurs or not, depends on the ability of a growing thrombus to resist forces exerted on its structure. This manuscript provides the first known in vivo measurement of the stresses that clots can withstand, before yielding to the surrounding blood flow. Namely, Lattice-Boltzmann Method flow simulations are performed based on 3D clot geometries. The latter are estimated from intravital microscopy images of laser-induced injuries in cremaster microvasculature of live mice. In addition to reporting the blood clot yield stresses, we also show that the thrombus 'core' does not experience significant deformation, while its 'shell' does. This indicates that the latter is more prone to embolization. Hence, drugs should be designed to target the shell selectively, while leaving the core intact (to minimize excessive bleeding). Finally, we laid down a foundation for a nondimensionalization procedure, which unraveled a relationship between clot mechanics and biology. Hence, the proposed framework could ultimately lead to a unified theory of thrombogenesis, capable of explaining all clotting events. Thus, the findings presented herein will be beneficial to the understanding and treatment of heart attacks, strokes and hemophilia

Mathematical modeling of thrombus formation in idealized models of aortic dissection: Initial findings and potential applications

Aortic dissection is a major aortic catastrophe with a high morbidity and mortality risk caused by the formation of a tear in the aortic wall. The development of a second blood filled region defined as the “false lumen” causes highly disturbed flow patterns and creates local hemodynamic conditions likely to promote the formation of thrombus in the false lumen. Previous research has shown that patient prognosis is influenced by the level of thrombosis in the false lumen, with false lumen patency and partial thrombosis being associated with late complications and complete thrombosis of the false lumen having beneficial effects on patient outcomes. In this paper, a new hemodynamics-based model is proposed to predict the formation of thrombus in Type B dissection. Shear rates, fluid residence time, and platelet distribution are employed to evaluate the likelihood for thrombosis and to simulate the growth of thrombus and its effects on blood flow over time. The model is applied to different idealized aortic dissections to investigate the effect of geometric features on thrombus formation. Our results are in qualitative agreement with in-vivo observations, and show the potential applicability of such a modeling approach to predict the progression of aortic dissection in anatomically realistic geometries

Surgical excision of renal cell carcinoma with caval and intra-atrial tumour thrombus extension using deep hypothermic circulatory arrest

Surgery for tumour thrombus extension in Renal Cell Carcinoma may be associated with a good prognosis if no distant metastases are identified and if the thrombus can be completely excised. The surgical approach chosen will depend on the level of tumour thrombus extension. We present a case of Renal Cell Carcinoma in the right kidney with tumour thrombus extension into the right atrium. This was successfully removed by right radical nephrectomy and excision of the atrial thrombus using cardio-pulmonary bypass and deep hypothermic circulatory arrest. This is the first procedure of its kind to be undertaken in Malta.peer-reviewe