title: Measurement of fractional flow reserve to assess the functional severity of coronary-artery stenoses.
abstract: BACKGROUND
  The clinical significance of coronary-artery stenoses of moderate severity can be difficult to determine. Myocardial fractional flow reserve (FFR) is a new index of the functional severity of coronary stenoses that is calculated from pressure measurements made during coronary arteriography. We compared this index with the results of noninvasive tests commonly used to detect myocardial ischemia, to determine the usefulness of the index.
  
  
  METHODS
  In 45 consecutive patients with moderate coronary stenosis and chest pain of uncertain origin, we performed bicycle exercise testing, thallium scintigraphy, stress echocardiography with dobutamine, and quantitative coronary arteriography and compared the results with measurements of FFR.
  
  
  RESULTS
  In all 21 patients with an FFR of less than 0.75, reversible myocardial ischemia was demonstrated unequivocally on at least one noninvasive test. After coronary angioplasty or bypass surgery was performed, all the positive test results reverted to normal. In contrast, 21 of the 24 patients with an FFR of 0.75 or higher tested negative for reversible myocardial ischemia on all the noninvasive tests. No revascularization procedures were performed in these patients, and none were required during 14 months of follow-up. The sensitivity of FFR in the identification of reversible ischemia was 88 percent, the specificity 100 percent, the positive predictive value 100 percent, the negative predictive value 88 percent, and the accuracy 93 percent.
  
  
  CONCLUSIONS
  In patients with coronary stenosis of moderate severity, FFR appears to be a useful index of the functional severity of the stenoses and the need for coronary revascularization.
authors.affiliation: Department of Cardiology, Catharina Hospital, Eindhoven, the Netherlands.
authors.forename: N H
authors.initials: NH
authors.lastname: Pijls
authors.forename: B
authors.initials: B
authors.lastname: De Bruyne
authors.forename: K
authors.initials: K
authors.lastname: Peels
authors.forename: P H
authors.initials: PH
authors.lastname: Van Der Voort
authors.forename: H J
authors.initials: HJ
authors.lastname: Bonnier
authors.forename: J J
authors.initials: JJ
authors.lastname: Bartunek J Koolen
authors.forename: J J
authors.initials: JJ
authors.lastname: Koolen
mesh_terms: D000328:Adult; D000368:Aged; D017023:Coronary Angiography; D003326:Coronary Circulation; D003327:Coronary Disease / Q000145:classification* / Q000175:diagnosis / Q000503:physiopathology; D004280:Dobutamine; D004452:Echocardiography / Q000379:methods; D005069:Evaluation Studies as Topic; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011312:Pressure; D011877:Radionuclide Imaging; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
chemical_list: D004280:Dobutamine