Clinical Study Data Request Registered Users, Please Login

Proposal 637

Title of the Proposed Research

Relationship of Activated Clotting Time and Bleeding Related Outcomes in the FUTURA OASIS-8 Trial

Lead Researcher

Sripal Bangalore, MD, MHA, FACC, FSCAI


New York University School of Medicine
New York, NY, USA

Funding Source


Potential Conflicts of Interest


Data Sharing Agreement Date

12 September 2013

Lay Summary

The background to the research

Activated clotting time (ACT) is used as a measure of degree of anticoagulation (how thin the blood is) in response to the use of unfractionated heparin (UFH) (blood thinner) during percutaneous coronary intervention (PCI) (stenting procedure of the heart arteries). The target goal for ACT is a balance between the risk of ischemic complications (complications due to clotting) (due to inadequate blood thinning reflected by a low ACT) vs. bleeding complications (due to excessive blood thinning reflected by a high ACT). However, the relationship of ACT with bleeding and ischemic events in patients receiving both UFH and low molecular weight heparin (LMWH) is not well defined. In addition, an optimal ACT target for such patients receiving both UFH and LMWH is not well defined. Moreover, most of the prior studies that evaluated ACT and bleeding predated modern use of potent antiplatelet agents (such as clopidogrel and GP IIb/IIIa inhibitors).

How the research will add to medical science or improve patient care

The research will address the relationship of ACT value to bleeding and ischemic events and will help identify an optimal ACT at which bleeding is minimized without any excess ischemic endpoints. It will therefore help patient care.

The aims and objectives of the research

Our objectives are 2-folds
  1. To assess the relationship between quartiles of maximal ACT achieved and bleeding and ischemic outcomes
  2. To evaluate an optimal ACT which has the best balance between safety (bleeding) and efficacy (ischemic/clotting outcomes)
How the research will be conducted

Research will be conducted using data from the FUTURA OASIS-8 trial which enrolled patients with acute coronary syndromes and were receiving fondaparinux and were randomized to two doses of UFH. Patients will be divided into quartiles based on maximal ACT achieved. The risk of bleeding and ischemic endpoints will be assessed. Receiver operating characteristic curves will be constructed to identify optimal ACT values that has the best balance of efficacy and safety.

How the findings will be interpreted and communicated

The findings will be interpreted within the limits of a non-randomized design and will be communicated by presentations at national/international conferences and publication in high-tier journals.

Study Data Provided

Study AR1108888: FondaparinUx Trial with Unfractionated Heparin (UFH) during Revascularization in Acute Coronary Syndromes (ACS) (FUTURA). A prospective study evaluating the safety of two regimens of adjunctive intravenous UFH during PCI in high risk patients with Unstable Angina/Non ST segment elevation myocardial infarction (UA/NSTEMI) initially treated with subcutaneous fondaparinux and referred for early coronary angiography (OASIS 8)

Statistical Analysis Plan

This will be added after the research is published.

Publication Citation