A Trial in Stable Intermediate Coronary Lesions and Grey-zone FFR Values
Condition: Grey-zone Fractional Flow Reserve; Intermediate Coronary Lesions; Stable Angina; Coronary Physiology
MeSH terms: Angina, Stable
Study type: Interventional

Summary: 
      In this randomised controlled trial of patients with stable angina and documented
      intermediate coronary disease with indeterminate or "grey-zone" Fractional Flow Reserve (FFR)
      we will randomise patients to either optimal medical therapy alone versus optimal medical
      therapy with PCI and they will be followed up for the primary endpoint of anginal control as
      measured by the Seattle Angina Questionnaire at 3 months.
    

Detailed description: 
      Pressure derived fractional flow reserve (FFR) is recognised as being the gold standard
      method of assessing the physiological significance of angiographically intermediate lesions.
      A grey-zone exists between the originally validated cut-off for ischemia of <0.75 and the
      conventionally adopted cut- off of ≤0.80. Pilot data from our centre has suggested that only
      1 in 3 coronary arteries with grey-zone FFR values demonstrate myocardial perfusion defects
      on stress cardiac MRI and others have suggested that the clinical outcomes in patients with
      grey-zone FFR are favorable with medical therapy alone. As such, stenting all lesions with
      grey-zone FFR (as currently recommended) may represent over-treatment and could attenuate the
      overall benefit of an FFR strategy. In addition to this there are flow derived resistance
      indices of stenosis severity that have superior diagnostic accuracy and may be helpful in
      correctly classifying patients with grey-zone FFR. In this study we will a comprehensive
      analysis of lesions with grey-zone FFR values (0.75-0.82 inclusive) using invasive hyperemic
      pressure, flow and resistance derived indices of severity with quantitative and qualitative
      3T perfusion MRI to enable identification of the best invasive predictors of true perfusion
      defects on 3T cardiac MRI. Patients will be randomised to optimal medical therapy alone
      versus optimal medical therapy with PCI and followed up for the primary endpoint of anginal
      control as measured by the Seattle Angina Questionnaire at 3 months.
    

Intervention name(s): PCI; Optimal Medical Therapy
Intervention type(s): Procedure; Drug
Intervention description(s): Patients will have balloon angioplasty and coronary stent insertion for their grey-zone FFR lesion.; Optimal Medical therapy consists of secondary prevention which will include high dose statin and aspirin as well as anti-anginal therapy according to ESC 2013 international treatment guidelines for stable angina as follows; B-Blocker or Calcium channel blocker as first line agents and Nicorandil or Nitrates or Ranolazine as second line treatment titrated against symptoms to maximum tolerated dose. ACE inhibitors or Angiotensin Receptor Blockers will be prescribed if patients also have a diagnosis of hypertension, LVEF ≤40%, diabetes or CKD where appropriate.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment