title: Efficacy of pressure parameters obtained during contrast medium-induced submaximal hyperemia in the functional assessment of intermediate coronary stenosis.
abstract: BACKGROUND
  Despite evidence demonstrating the superiority of percutaneous coronary intervention guided by fractional flow reserve (FFR), FFR evaluation has not been widely adopted. We sought to determine the diagnostic performance of baseline conditions and contrast medium-induced pressure indices in predicting FFR. We hypothesized that the contrast medium-induced end-diastolic pressure parameter would offer superior diagnostic agreement with FFR, compared to other indices.
  
  
  RESULTS
  Ninety-one intermediate stenoses in 75 patients were studied prospectively. The baseline distal coronary pressure to aortic pressure ratio (Pd/Pa) and end-diastolic instantaneous Pd/Pa 60 ms before the electrocardiographic R-wave (ED-Pd/Pa) were measured; then, after intracoronary injection of 6 mL contrast medium at 3 mL/s, Pd/Pa (C-Pd/Pa) and end-diastolic Pd/Pa (C-ED-Pd/Pa) were obtained. Subsequently, conventional FFR was measured as a reference standard. Of the 91 lesions, 11 (12.1%) were excluded because of suboptimal data acquisition, leaving 80 for final analysis. C-ED-Pd/Pa values (median 0.80 [interquartile range 0.70-0.88]) were significantly lower than conventional FFR (0.83 [0.75-0.89], P<0.01), whereas Pd/Pa (0.93 [0.90-0.96], P<0.01), ED-Pd/Pa (0.91 [0.87-0.93], P<0.01), and C-Pd/Pa (0.85 [0.79-0.90], P<0.05) were significantly higher. Correlation coefficients (R) with conventional FFR were 0.74 (standard error of the estimate [SEE] 0.067, P<0.0001), 0.78 (SEE 0.062, P<0.0001), 0.85 (SEE 0.052, P<0.0001), and 0.93 (SEE 0.037, P<0.0001) for Pd/Pa, ED-Pd/Pa, C-Pd/Pa, and C-ED-Pd/Pa, respectively. Diagnostic accuracy was 81.2%, 83.8%, 87.5% and 93.8% for Pd/Pa, ED-Pd/Pa, C-Pd/Pa, and C-ED-Pd/Pa, respectively.
  
  
  CONCLUSIONS
  Among baseline indices and contrast-induced pressure parameters, C-ED-Pd/Pa is a novel, feasible, and high-performance measure for the physiological assessment of intermediate coronary stenosis.
authors.affiliation: Department of Cardiovascular Medicine, Tsuchiura Kyodo General Hospital, Tsuchiura, Japan.
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Kanaji
authors.affiliation: Department of Cardiovascular Medicine, Tsuchiura Kyodo General Hospital, Tsuchiura, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Murai
authors.affiliation: Department of Cardiovascular Medicine, Tsuchiura Kyodo General Hospital, Tsuchiura, Japan.
authors.forename: Tetsumin
authors.initials: T
authors.lastname: Lee
authors.affiliation: Department of Cardiovascular Medicine, Tsuchiura Kyodo General Hospital, Tsuchiura, Japan.
authors.forename: Junji
authors.initials: J
authors.lastname: Matsuda
authors.affiliation: Department of Cardiovascular Medicine, Tsuchiura Kyodo General Hospital, Tsuchiura, Japan.
authors.forename: Eisuke
authors.initials: E
authors.lastname: Usui
authors.affiliation: Department of Cardiovascular Medicine, Tsuchiura Kyodo General Hospital, Tsuchiura, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Araki
authors.affiliation: Department of Cardiovascular Medicine, Tsuchiura Kyodo General Hospital, Tsuchiura, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Niida
authors.affiliation: Department of Cardiovascular Medicine, Tsuchiura Kyodo General Hospital, Tsuchiura, Japan.
authors.forename: Sadamitsu
authors.initials: S
authors.lastname: Ichijo
authors.affiliation: Department of Cardiovascular Medicine, Tsuchiura Kyodo General Hospital, Tsuchiura, Japan.
authors.forename: Rikuta
authors.initials: R
authors.lastname: Hamaya
authors.affiliation: Department of Cardiology, Kameda Medical Center, Chiba, Japan.
authors.forename: Taishi
authors.initials: T
authors.lastname: Yonetsu
authors.affiliation: Cardiovascular Center, Yokosuka Kyosai Hospital, Yokosuka, Kanagawa, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Kimura
authors.affiliation: Department of Cardiovascular Medicine, Tsuchiura Kyodo General Hospital, Tsuchiura, Japan. Electronic address: kaz@joy.email.ne.jp.
authors.forename: Tsunekazu
authors.initials: T
authors.lastname: Kakuta
mesh_terms: D000368:Aged; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology*; D006328:Cardiac Catheterization; D003287:Contrast Media / Q000494:pharmacology*; D017023:Coronary Angiography; D023921:Coronary Stenosis / Q000175:diagnosis* / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D053805:Fractional Flow Reserve, Myocardial / Q000502:physiology*; D006801:Humans; D006940:Hyperemia / Q000139:chemically induced* / Q000503:physiopathology; D008297:Male; D011446:Prospective Studies; D015203:Reproducibility of Results; D013997:Time Factors
chemical_list: D003287:Contrast Media
keywords: Angioplasty; Atherosclerosis; Fractional flow reserve; Ischemia; Revascularization