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K Ouriel

Publications and source records attributed to K Ouriel.

149 records · Page 9Linked to original sources
PubMedDate not supplied

Reteplase in the treatment of peripheral arterial and venous occlusions: a pilot study.

PURPOSE: Reteplase, a truncated mutant of tissue plasminogen activator, has been used successfully in the treatment of acute coronary occlusion, but, heretofore, it has not been investigated in the setting of peripheral vascular occlusion. Reteplase is a potential recombinant thrombolytic agent that may offer an appropriate alternative to currently employed plasminogen activators. MATERIALS AND METHODS: Over a 6-month period reteplase was used to treat peripheral vascular occlusions at five centers in the United States. The agent was used in peripheral arterial occlusion (n = 26, 70.3%) or venous occlusion (n = 11, 29.7%), in doses ranging from 0.5 to 2.0 U/h, infused directly into the thrombus. A lacing dose (4.3 +/- 0.9 U) was employed in 17 patients (45.9%), and 25 patients (67.6%) received concurrent heparin therapy in a subtherapeutic dose (n = 14, 37.8%) or as full therapeutic anticoagulation (n = 11, 29.7%). RESULTS: The 26 patients with arterial occlusions received a total dose of reteplase that averaged 20.5 U +/- 5.3 (mean +/- SEM), ranging from 3.5 to 82 U. The duration of infusion was 19.3 hours +/- 2.4 with a range of 0.2-36 hours. Complete dissolution of the occluding thrombus was achieved in 23 patients (88.5%). Hemorrhagic complications developed in eight patients (30.8%) and were major in five patients (19.2%). No patient experienced intracranial bleeding. Although there was no association between the dose regimen and thrombolytic efficacy, bleeding complications appeared to be more frequent as the dose was increased from 0.5 to 2.0 U/h. The 11 patients treated for deep venous thrombi received an average of 32.6 U +/- 7.4 of reteplase, ranging from 6 to 75 U over a mean length of time of 31.1 hours +/- 7.3 (range, 4-84 hours). Complete dissolution of thrombus occurred in eight patients (72.7%). Hemorrhagic complications developed in three patients (27.3%) and one of the episodes was major (9.1%). No patient experienced intracranial hemorrhage. CONCLUSIONS: Reteplase appears to be an acceptable alternative thrombolytic agent with a satisfactory safety and efficacy profile in the setting of peripheral arterial and venous occlusion. As such, it may provide an attractive alternative for the treatment of peripheral arterial and venous thrombotic occlusions. However, definitive conclusions must await the results of controlled comparisons of reteplase to other thrombolytic agents.

Adult↗
PubMedDate not supplied

Surgery versus thrombolytic therapy in the management of peripheral arterial occlusions.

Thrombolytic therapy has been used as an alternative to surgery in the treatment of peripheral arterial occlusion. Only recently has data from controlled clinical trials become available to allow comparison of the results of both treatment modalities. This article reviews surgical results in the treatment of peripheral arterial occlusions, the history of and techniques for thrombolysis in peripheral arterial occlusion, and the results of studies comparing the two treatments.

Arterial Occlusive Diseases↗
PubMedDate not supplied

Assessing clot lysis strategies using a simplified mathematical model.

This paper attempts to describe lysis of a clot by infusion of lytic agent using a simple geometrical approach, in which the rate of clot lysis is assumed proportional to the exposed surface of the clot and the concentration of lytic agent. Six simple realizations (a)-(f) of this basic model are developed which account for the dependence of clot lysis time on five different clot geometries. In all six cases the clot is initially described as a uniform cylinder which totally occludes a vessel. In model (a) lysis proceeds as an advancing front at the proximal face of the clot. In model (b) lysis proceeds radially outwards from the central axis of the vessel while in model (c) lysis occurs radially inwards from the surface adjacent the wall, of the cylinder. In models (d) and (e) it is assumed that the clot breaks into a uniform spherical and cylindrical fragments, respectively, while model (f) uses the spherical fragment model combined with a lytic agent concentration which decreases with time. The validity of the models was assessed using previously published data from 76 patients in whom lysis time and clot size were recorded. Least squares linear regression analysis based on the six model equations yielded highly significant correlation coefficients r2 of 0.457, 0.412, 0.412, 0.495, 0.469, 0.663 for models (a)-(f), respectively. The results suggest that when a constant lytic agent concentration is assumed, no single geometry accounts for significantly more variation than any other, but that a combination of varying lytic agent concentration and clot geometry significantly influences clot lysis time and accounts for much of the observed variation.

Humans↗