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Related Experiment Video

Updated: Aug 22, 2025

Evaluation of Coronary Flow Reserve After Myocardial Ischemia Reperfusion in Rats
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What About All the Recent "Negative" FFR Trials?

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Fractional flow reserve (FFR) is a valuable tool, but recent trials question its utility. Further research should focus on discordant decisions and clinical outcomes for percutaneous coronary intervention versus medical therapy.

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Area of Science:

  • Cardiovascular medicine
  • Interventional cardiology
  • Clinical trial design

Background:

  • Fractional flow reserve (FFR) has evolved from animal studies to become a Class IA guideline recommendation over 30 years.
  • Recent 2021 randomized trials (FLOWER-MI, RIPCORD-2, FUTURE, FAME 3) yielded negative results, prompting re-evaluation of FFR's clinical role.

Purpose of the Study:

  • To critically examine recent negative FFR randomized trials.
  • To draw insights into FFR's current utility and limitations.
  • To evaluate study design and interpretation in cardiovascular trials.

Main Methods:

  • Review and critical analysis of key randomized controlled trials published in 2021.
  • Focus on discordant decisions between coronary angiography and FFR measurements.
  • Examination of clinical endpoints related to percutaneous coronary intervention (PCI) versus medical therapy.

Main Results:

  • Recent large randomized trials suggest FFR may not improve outcomes as previously expected.
  • Discordance between anatomical stenosis (angiography) and physiological significance (FFR) requires careful consideration.
  • The interpretation of "negative" trials necessitates a nuanced approach to study design and clinical application.

Conclusions:

  • The clinical utility of FFR is being questioned following recent negative trial outcomes.
  • Future research should prioritize understanding discrepancies between angiography and FFR.
  • Identifying specific patient subgroups and clinical endpoints where PCI offers clear advantages over medical therapy is crucial.