Dataset Information

Mathematical Modelling of Intravenous Thrombolysis in Acute Ischaemic stroke: Effects of Dose Regimens on Levels of Fibrinolytic Proteins and Clot Lysis Time.

ABSTRACT: Thrombolytic therapy is one of the medical procedures in the treatment of acute ischaemic stroke (AIS), whereby the tissue plasminogen activator (tPA) is intravenously administered to dissolve the obstructive blood clot. The treatment of AIS by thrombolysis can sometimes be ineffective and it can cause serious complications, such as intracranial haemorrhage (ICH). In this study, we propose an efficient mathematical modelling approach that can be used to evaluate the therapeutic efficacy and safety of thrombolysis in various clinically relevant scenarios. Our model combines the pharmacokinetics and pharmacodynamics of tPA with local clot lysis dynamics. By varying the drug dose, bolus-infusion delay time, and bolus-infusion ratio, with the FDA approved dosing protocol serving as a reference, we have used the model to simulate 13 dose regimens. Simulation results are compared for temporal concentrations of fibrinolytic proteins in plasma and the time that is taken to achieve recanalisation. Our results show that high infusion rates can cause the rapid degradation of plasma fibrinogen, indicative of increased risk for ICH, but they do not necessarily lead to fast recanalisation. In addition, a bolus-infusion delay results in an immediate drop in plasma tPA concentration, which prolongs the time to achieve recanalisation. Therefore, an optimal administration regimen should be sought by keeping the tPA level sufficiently high throughout the treatment and maximising the lysis rate while also limiting the degradation of fibrinogen in systemic plasma. This can be achieved through model-based optimisation in the future.

SUBMITTER: Gu B

PROVIDER: S-EPMC6471481 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Mathematical Modelling of Intravenous Thrombolysis in Acute Ischaemic stroke: Effects of Dose Regimens on Levels of Fibrinolytic Proteins and Clot Lysis Time.

Gu Boram B Piebalgs Andris A Huang Yu Y Longstaff Colin C Hughes Alun D AD Chen Rongjun R Thom Simon A SA Xu Xiao Yun XY

Pharmaceutics 20190307 3

Thrombolytic therapy is one of the medical procedures in the treatment of acute ischaemic stroke (AIS), whereby the tissue plasminogen activator (tPA) is intravenously administered to dissolve the obstructive blood clot. The treatment of AIS by thrombolysis can sometimes be ineffective and it can cause serious complications, such as intracranial haemorrhage (ICH). In this study, we propose an efficient mathematical modelling approach that can be used to evaluate the therapeutic efficacy and safe ...[more]

PMID: 30866489

Similar Datasets

Project description:Abdominal aortic aneurysms (AAAs) involve chronic overexpression of proteases in the aortic wall that result in disruption of elastic fibers and consequent loss of vessel elasticity. Nearly 75% of AAAs contain flow-obstructing, fibrin-rich intraluminal thrombi (ILT), which act as a) a bioinert shield, protecting the underlying AAA wall from high hemodynamic stresses, and b) a reservoir of inflammatory cells and proteases that cause matrix breakdown. For these reasons, restoring flow through the aorta lumen and facilitating transmural diffusion of therapeutics from circulation to the AAA wall must be achieved by slow thrombolysis of the ILT to render it porous without rapid breakdown. Intravenously dosed tissue plasminogen activator (tPA) has been shown to rapidly lyse ILTs in acute stroke and myocardial infarctions. For future use in opening up AAA segments, in this study, we investigated the ability of tPA released from poly(lactic-co-glycolic acid) nanoparticles (PLGA NPs) to slowly lyse fibrin clots without inducing proteolytic injury and matrix synthesis-inhibitory effects on cultured rat aneurysmal smooth muscle cells (EaRASMCs). Fibrin clot lysis time was greatly extended over that in presence of exogenous tPA. Surface functionalization of NPs with a cationic amphiphile allowed them to bind to anionic fibrin clot, release tPA at a slower rate and to lyse the clot as a front proceeding outwards in unlike the more rapid and homogenous lysis that occurred due to anionic PLGA NPs. Elastic matrix content was decreased in EaRASMC cultures exposed to byproducts of clot lysis with exogenous tPA, but not tPA-NPs, and was likely due to increased proteolytic activity (MMPs, plasmin) in EaRASMC cultures exposed to exogenous tPA-lysed clots. Our results suggest that gradual ILT lysis via slow release of tPA from NPs will be likely beneficial over exogenous tPA delivery in preserving elastic matrix content and attenuating matrilysis in the adjoining AAA wall, in vivo, while rendering the ILT porous to facilitate transmural delivery of endoluminally delivered AAA therapeutics.

Project description:BackgroundFor acute ischaemic stroke patients, it is uncertain whether intravenous thrombolysis combined with statins might increase the therapeutic effect. Additionally, using high-intensity statins after thrombolysis may increase the risk of bleeding in patients. Asian stroke patients often take low-dose statins. It is speculated that reducing the dose of statins may improve the risk of bleeding.MethodsData from consecutive acute ischaemic stroke patients with intravenous thrombolysis were prospectively collected. Efficacy outcomes included NIHSS (National Institutes of Health Stroke Scale) score improvement at 7 days after admission and mRS (Modified Rankin Scale) improvement at 90 days. Safety outcomes included haemorrhage events (intracerebral haemorrhage and gastrointestinal haemorrhage) in the hospital and death events within 2 years.ResultsThe study finally included 215 patients. The statin group had a higher percentage of NIHSS improvement at 7 days (p < 0.001) and a higher percentage of a favourable functional outcome (FFO, mRS < = 2) (p < 0.001) at 90 days. The statin group had a lower percentage of intracerebral haemorrhage (p < 0.001) and gastrointestinal haemorrhage (p = 0.003) in the hospital and a lower percentage of death events (p < 0.001) within 2 years. Logistic regression indicated that statin use was significantly related to NIHSS improvement (OR = 4.697, p < 0.001), a lower percentage of intracerebral haemorrhage (OR = 0.372, p = 0.049) and gastrointestinal haemorrhage (OR = 0.023, p = 0.016), and a lower percentage of death events (OR = 0.072, p < 0.001).ConclusionFor acute ischaemic stroke patients after intravenous thrombolysis, the use of low-dose statins was related to NIHSS improvement at 7 days and inversely related to haemorrhage events in the hospital and death events within 2 years, especially for moderate stroke or noncardioembolic stroke patients.

Project description:ObjectiveSeveral studies indicate that only a small proportion of patients with acute ischaemic stroke are treated with intravenous thrombolysis. Indications and contraindications for this treatment are usually based on the inclusion and exclusion criteria of randomised clinical trials. The trial context of these criteria hampers implementation in real life settings. We therefore aimed to obtain specialist opinion in a Delphi consensus on these contraindications.MethodsWe used the Delphi approach on an international group of specialists in the field of thrombolysis. Inclusion and exclusion criteria were reworded into 18 quantitatively phrased propositions. Feedback consisted of the median score, interquartile range and the panellist's own score in the previous round. For each item, we defined consensus as the achievement of an interdecile range within two prespecified clinically relevant units.ResultsThirty-one specialists participated in the first round and 30 completed all three rounds. Consensus was reached on 12 of the 18 propositions: previous ischaemic stroke, head trauma and gastrointestinal tract bleeding should not have taken place earlier than 1.5 months, 2 months and 14 days, respectively; the severity of the neurological deficit is defined as a National Institutes of Health Stroke Scale (NIHSS) score of 2-3 or more, and blood pressure level should not be >185/110 mmHg; platelet count should be >90x10(12)/l, glucose levels 2.7-22 mmol/l, international normalised ratio <1.5 and activated partial thromboplastin time <50 s. No consensus was reached on propositions concerning the stroke onset to treatment time, patient's age, recent medical procedures, spontaneous improvement rate and blood pressure treatment.ConclusionsWe present specialists' opinion on contraindications for intravenous thrombolysis in ischaemic stroke. The results of this study may be relevant for routine clinical practice as they may help to increase the number of treated patients.

Dataset Information

Mathematical Modelling of Intravenous Thrombolysis in Acute Ischaemic stroke: Effects of Dose Regimens on Levels of Fibrinolytic Proteins and Clot Lysis Time.

Publications

Mathematical Modelling of Intravenous Thrombolysis in Acute Ischaemic stroke: Effects of Dose Regimens on Levels of Fibrinolytic Proteins and Clot Lysis Time.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets