Visual Estimation of Coronary Fractional Flow Reserve From High-definition Computed Tomographic Coronary Angiography

NCT02179957 | Completed

• 2 other identifiers: 14/P/06614/WS/0121
• Study Type: observational
• Target: 85
• Locations: 1 country
• Sites: 1

Brief Summary

The identification of abnormal narrowing of a blood vessel from non-invasive coronary angiography remains an exciting goal. While Computed Tomography (CT) has established a clear role in patients it retains some limitations. Primarily, alterations in blood flow leading to a restriction in blood supply to tissues cannot be accurately predicted from the anatomical assessment of an abnormal narrowing in a blood vessel - a limitation of both invasive, and computed tomographic, angiography. This is important, as there is now a raft of evidence demonstrating that revascularisation should only be considered in the presence of a restriction in blood supply to tissues. The gold standard method of identifying a restriction in blood supply to tissues is measurement of the fractional flow reserve (FFR), a dimensionless value generated as a ratio between the circulatory pressure before and after a narrowing of a blood vessel. At present, patients with indeterminately significant abnormal narrowing in a blood vessel identified using CT must go on to have a further test for a restriction in blood supply to tissues, prior to any decision about revascularisation being made. As part of our governance commitment to maintaining our reporting standards, we undertake ongoing audit of our cardiac CT practice. The investigators recently identified a group of patients who have undergone FFR measurement as part of routine clinical care, and compared these to our clinical reports, to ensure that appropriate recommendations were being made. It appeared that the ability to predict important abnormal narrowing in a blood vessel was reasonable (\~70%) and hence we propose the formulation of a research question to explore this further. The primary objective of this study is to determine the accuracy of a visual assessment of the likely significance on blood flow of a narrowing of a blood vessel identified on cardiac CT, in comparison to invasive, fractional flow reserve. The secondary objective is to evaluate features of an abnormal narrowing in a blood vessel that is likely to have a significant impact on blood flow. The investigators' working hypothesis is that cardiac CT FFR is a useful predictor of abnormal narrowing in a blood vessel.

Conditions

Stenoses; Ischaemia

Keywords

Stenoses; Ischaemia; haemodynamics; fractional flow reserve (FFR); computed tomography (CT); cardiac

Outcome Measures

Primary Outcomes (1)

• Accuracy of a visual assessment of the likely haemodynamic significance of a stenosis identified on cardiac CT, in comparison to invasive, fractional flow reserve.

  The outcome measures will be the sensitivity, specificity, positive \& negative predictive values, and overall accuracy of the visual assessment .

  2 weeks

Secondary Outcomes (1)

• Odds ratios for features felt likely to contribute to the diagnosis (stenosis severity, stenosis length, proportion of downstream myocardium supplied, use of high-definition scanning)

  2 weeks

Study Arms (1)

CT and FFR

Coronary stenoses which have been analysed with both CT and FFR

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patients with coronary stenoses which have been analysed with both CT and FFR

You may qualify if:

• Patients with coronary stenoses which have been analysed with both CT and FFR

You may not qualify if:

• Under 18 years

Sponsors & Collaborators

• University Hospital Plymouth NHS Trust: lead

Study Sites (1)

Plymouth Hospitals NHS Trust

Plymouth, Devon, PL6 8DH, United Kingdom

Location

MeSH Terms

Conditions

Constriction, Pathologic; Ischemia

Condition Hierarchy (Ancestors)

Pathological Conditions, Anatomical; Pathological Conditions, Signs and Symptoms; Pathologic Processes

Study Officials

• Benjamin Clayton, MBBS

  Plymouth Hospital NHS Trust

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: June 30, 2014
• First Posted: July 2, 2014
• Study Start: June 1, 2014
• Primary Completion: June 1, 2014
• Study Completion: June 1, 2014
• Last Updated: July 2, 2014

Record last verified: 2014-06

Locations

GB (1)