title: Impact of Right Atrial Pressure on Fractional Flow Reserve Measurements: Comparison of Fractional Flow Reserve and Myocardial Fractional Flow Reserve in 1,600 Coronary Stenoses.
abstract: OBJECTIVE
  This study sought to assess the impact of a wide range of mean right atrial pressure (Pra) on fractional flow reserve (FFR) measurements.
  
  
  BACKGROUND
  FFR invasively assesses the ischemic potential of coronary stenoses. FFR is calculated as the ratio of mean distal coronary pressure (Pd) to mean aortic pressure (Pa) during maximal hyperemia. The Pra is considered to have little impact if it is within normal range, so it is neglected in the formula.
  
  
  METHODS
  In 1,676 stenoses of 1,235 patients undergoing left-right heart catheterization for ischemic (642 [52%]) or valvular heart disease (593 [48%]), the authors compared the FFR values calculated without accounting for Pra (FFR= Pd/Pa) to the corresponding myocardial fractional flow reserve (FFRmyo) values accounting for Pra (FFRmyo = Pd - Pra/Pa - Pra).
  
  
  RESULTS
  The median Pra was 7 (interquartile range [IQR]: 5 to 10) mm Hg with a maximum of 27 mm Hg. The correlation and agreement between FFR and FFRmyo was excellent (R(2) = 0.987; slope 1.096 ± 0.003). The median FFR (0.85; IQR: 0.78 to 0.91) was slightly but statistically significantly higher than the median FFRmyo (0.83; IQR: 0.76 to 0.90; p < 0.001) with a median difference of 0.01 (IQR: 0.01 to 0.02). Values of FFR above the cutoff of 0.80 provided an FFRmyo ≤0.80 in 110 (9%) stenoses. No FFR value above 0.80 provided an FFRmyo ≤0.75.
  
  
  CONCLUSIONS
  The difference between FFR and FFRmyo was minimal even in patients with markedly increased Pra. FFR values above the gray zone (i.e., >0.80) did not yield values below the gray zone (i.e., ≤0.75) in any case, which suggests that the impact of right atrial pressure on FFR measurement is indeed negligible.
authors.affiliation: Cardiovascular Centre Aalst, OLV Clinic, Aalst, Belgium; Department of Cardiology, University Heart Centre Graz, Graz, Austria.
authors.forename: Gabor G
authors.initials: GG
authors.lastname: Toth
authors.affiliation: Cardiovascular Centre Aalst, OLV Clinic, Aalst, Belgium.
authors.forename: Bernard
authors.initials: B
authors.lastname: De Bruyne
authors.affiliation: Cardiovascular Centre Aalst, OLV Clinic, Aalst, Belgium; Department of Cardiology, University Hospital of Amiens, Amiens, France.
authors.forename: Dan
authors.initials: D
authors.lastname: Rusinaru
authors.affiliation: Cardiovascular Centre Aalst, OLV Clinic, Aalst, Belgium; Department of Advanced Biomedical Sciences, Federico II University, Naples, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Di Gioia
authors.affiliation: Cardiovascular Centre Aalst, OLV Clinic, Aalst, Belgium.
authors.forename: Jozef
authors.initials: J
authors.lastname: Bartunek
authors.affiliation: Cardiovascular Centre Aalst, OLV Clinic, Aalst, Belgium.
authors.forename: Mariano
authors.initials: M
authors.lastname: Pellicano
authors.affiliation: Cardiovascular Centre Aalst, OLV Clinic, Aalst, Belgium.
authors.forename: Marc
authors.initials: M
authors.lastname: Vanderheyden
authors.affiliation: Cardiovascular Centre Aalst, OLV Clinic, Aalst, Belgium.
authors.forename: Julien
authors.initials: J
authors.lastname: Adjedj
authors.affiliation: Cardiovascular Centre Aalst, OLV Clinic, Aalst, Belgium.
authors.forename: William
authors.initials: W
authors.lastname: Wijns
authors.affiliation: Department of Cardiology, Catharina Hospital, Eindhoven, the Netherlands; Eindhoven University of Technology, Eindhoven, the Netherlands.
authors.forename: Nico H J
authors.initials: NH
authors.lastname: Pijls
authors.affiliation: Cardiovascular Centre Aalst, OLV Clinic, Aalst, Belgium; Department of Advanced Biomedical Sciences, Federico II University, Naples, Italy. Electronic address: emanuele.barbato@olvz-aalst.be.
authors.forename: Emanuele
authors.initials: E
authors.lastname: Barbato
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D062186:Arterial Pressure; D016280:Atrial Function, Right; D062185:Atrial Pressure; D006328:Cardiac Catheterization; D023921:Coronary Stenosis / Q000175:diagnosis* / Q000503:physiopathology; D003331:Coronary Vessels / Q000503:physiopathology*; D005260:Female; D053805:Fractional Flow Reserve, Myocardial; D006801:Humans; D006940:Hyperemia / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012720:Severity of Illness Index
keywords: fractional flow reserve; heart failure; myocardial fractional flow reserve; right atrial pressure