Medical Research: What are the main findings of the study?
Dr. Johnson: Our study had 3 main findings.
- First, the numeric fractional flow reserve (FFR) value related continuously to risk, such that clinical events increased as FFR decreased and revascularization showed larger net benefit for lower baseline FFR values.
- Second, fractional flow reserve measured immediately after stenting also showed an inverse relationship with prognosis, likely due to its relationship with diffuse disease.
- Third, an fractional flow reserve-assisted strategy led to revascularization roughly half as often as an anatomy-based strategy, but with 20% fewer adverse events and 10% better angina relief.
Medical Research: What was most surprising about the results?Dr. Johnson: While clinicians mainly use fractional flow reserve as a binary variable, our novel results uncovered a continuous relationship between the “depth” of ischemia and subsequent outcomes for both medical therapy and revascularization.
Medical Research: What should clinicians and patients take away from your report?
Dr. Johnson: Like many tests in medicine, fractional flow reserve as a continuous variable provides more informed decisions than as a binary result. Lower FFR values signal the potential for greater benefit from revascularization. Physicians and
patients can use fractional flow reserve during shared decision making regarding treatment of coronary artery disease, integrating it with symptoms, anatomic complexity, procedural risk, and patient preferences.
Medical Research: What recommendations do you have for future research as a result of this study?
Dr. Johnson: Future outcomes studies can enrich the benefit of revascularization by enrolling lesions with lower FFR values, perhaps to the point of reducing
death and non-fatal MI alone independent of repeat procedures. The
prevalance of higher versus lower FFR values could serve as a useful,
global metric when studying patterns of CAD care.
Johnson NP, Tóth GG, Lai D, et al. Prognostic Value of Fractional Flow Reserve: Linking Physiologic Severity to Clinical Outcomes. J Am Coll Cardiol. 2014;64(16):1641-1654. doi:10.1016/j.jacc.2014.07.973