The Effect of Treatment with tPA on Factor VIII Elevation

Case Series

Ann Hematol Oncol. 2015;2(6): 1045.

The Effect of Treatment with tPA on Factor VIII Elevation

Samai AA MPH1,2 and Martin-Schild S MD, PhD¹*

¹Department of Neurology, Tulane University School of Medicine, USA

²Department of Epidemiology, Tulane School of Public Health and Tropical Medicine, USA

*Corresponding author: Sheryl Martin-Schild, Stroke Program, Department of Neurology, Tulane University School of Medicine, 1440 Canal Street, TB-52, Suite 1000, New Orleans, LA 70112, USA

Received: March 30, 2015; Accepted: June 05, 2015; Published: June 10, 2015

Abstract

Factor VIII (FVIII), an integral part of the clotting process, has been associated with increased incidence of acute ischemic stroke (AIS) when elevated. Intravenous tissue plasminogen activator (IV tPA) is a clot-busting drug and is the only FDA approved treatment for AIS. The effect of IV tPA on FVIII levels has not yet been explored in the context of ischemic stroke.

This case report will examine three unique cases and the effect of IV tPA administration on severely elevated FVIII levels. In case 1, the FVIII level decreases steadily to normal levels, post-tPA administration. In case 2, the FVIII level decreases dramatically in the acute phase post-tPA and then rises steadily to near-baseline level. Finally, in case 3, the FVIII level increases post-tPA and then remains consistently elevated for the duration of the acute phase.

The purpose of this case report is to explore the potential relationship between IV tPA and FVIII levels with respect to recanalization and post-stroke level of functioning.

Keywords: Factor VIII; Blood coagulation; Thrombosis; Thrombolytic; Ischemic stroke

Abbreviations

IV TPA: Intravenous Tissue Plasminogen Activator; AIS: Acute Ischemic Stroke; FVIII: Factor VIII; mRS: Modified Rankin Scale; NIHSS: National Institute of Health Stroke Scale; CTA: CT angiography; MRI: Magnetic Resonance Imaging; MRA: Magnetic Resonance Angiography; INR: International Normalized Ratio

Background

Intravenous recombinant tissue-type plasminogen activator (IV tPA), a thrombolytic agent, is the only medication approved by the Food and Drug Administration for treatment of acute ischemic stroke (AIS). Currently, IV tPA is recognized as the most effective treatment, and therefore the standard of care, in the acute setting of ischemic stroke [1-4].

A growing body of research has demonstrated the association between elevated levels (>150% activity) of coagulation factor VIII (FVIIII) and incident ischemic stroke [5]. Recent studies have also suggested that elevated FVIII may be associated to adverse in-hospital events and outcomes in the setting of AIS [6,7]. Furthermore, some evidence exists that FVIII levels may be impacted following the administration of IV tPA.

The following cases will explore three scenarios in which tPA was administered to AIS patients whose FVIII levels were elevated as classified by the laboratory-defined reference range of 50-150% activity.

Case Presentation

Case 1: Elevated FVIII pre-tPA reduced to normal post-tPA

Case 1 is a 48 year old Caucasian male with no significant past medical history and no reported tobacco, alcohol, or illicit drug use. Prior level of function was completely independent as measured by the modified Rankin Scale score (mRS = 0). The mRS ranges is the most commonly used functional outcome measure for stroke, ranging from 0 (no symptoms) to 6 (deceased). Upon admission, the patient exhibited normal baseline blood pressure and laboratory values with the exception of FVIII level which was severely elevated at 371.1% (Table 1, Figure 1).