Fractional Flow Reserve Versus Angiographically Guided Management to Optimise Outcomes in Unstable Coronary Syndromes

Summary

Background: In patients with acute non-ST elevation myocardial infarction (NSTEMI) coronary arteriography is usually recommended however visual interpretation of the coronary angiogram is subjective. A complementary diagnostic approach involves measuring the pressure drop across a coronary stenosis (fractional flow reserve, FFR) with a pressure-sensitive guidewire.

Hypothesis: Routine FFR measurement is feasible in NSTEMI patients and has additive diagnostic, clinical and health economic utility, as compared to angiography-guided standard care.

Design: A prospective multi-center randomized controlled trial in 350 NSTEMI patients with ≥1 coronary stenosis ≥30% severity (threshold for FFR measurement). Patients will be randomized immediately after coronary angiography to the FFR-guided group or angiography-guided group (FFR measured, not disclosed). All patients will then undergo FFR measurement in all vessels with a coronary stenosis ≥30% severity. FFR will be measured in culprit and non-culprit lesions in all patients. FFR will be disclosed to guide treatment in the FFR guided-group but not disclosed in the 'angiography-guided' group. In the FFR-guided group, an FFR\>0.80 will be an indication for medical therapy whereas an FFR≤0.80 will be an indication for revascularization by percutaneous coronary intervention (PCI) or coronary artery bypass surgery (CABG), as appropriate. The primary endpoint is the between-group difference in the proportion of patients allocated to medical management compared to revascularization. A key secondary composite outcome is the occurrence of cardiac death or hospitalization for myocardial infarction or heart failure. Other secondary outcomes include quality of life, hospitalization for unstable angina, coronary revascularization or stroke, and healthcare costs. Exploratory analyses will also assess the relationships between FFR and angiographic lesion characteristics (severity, culprit status). The minimum and average follow-up periods for the primary analysis are 6 and 18 months respectively. A secondary analysis with longer term follow-up (minimum 3 years) is planned. Screen failures who gave informed consent will be entered into a registry.

Importance: Our developmental clinical trial will address the feasibility of FFR measurement in NSTEMI and the influence of FFR disclosure on treatment decisions and health and economic outcomes.

Conditions

• NonST Elevation Myocardial Infarction
• Myocardial Infarction

Interventions

DEVICE

Fractional flow reserve

Guidewire-based coronary pressure measurement of myocardial FFR can identify obstructive coronary lesions in patients with stable coronary disease, and potentially, medically stabilized patients with recent MI. The FFR index is measured by a conventional coronary wire (0.014") with a pressure sensor on its distal tip during coronary hyperemia induced by intravenous or intracoronary adenosine. The potential diagnostic and prognostic benefit of guidewire-based coronary pressure measurement to inform the management and treatment of patients with recent acute NSTEMI will be assessed.

Sponsors & Collaborators

• British Heart Foundation

  collaborator OTHER

• Abbott Medical Devices

  collaborator INDUSTRY

• University of Glasgow

  collaborator OTHER

• NHS National Waiting Times Centre Board

  lead OTHER

Principal Investigators

• Colin Berry, MD PhD · University of Glasgow

• Robert Henderson, MD FRCP · Nottingham University Hospitals, Nottingham, UK

• Ian Ford, PhD · Robertson Centre for Biostatistics - University of Glasgow

• Andrew Briggs, PhD · Health Economics and Health Technology Assessment, University of Glasgow

Study Design

Allocation

RANDOMIZED

Purpose

DIAGNOSTIC

Masking

QUADRUPLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2011-10-31

Primary Completion

2014-06-30

Completion

2020-06-30

Countries

• United Kingdom

Study Locations