title: New parameter of the right gastroepiploic arterial graft using the power spectral analysis device named MemCalc soft.
abstract: OBJECTIVE
  Transit-time flow measurement (TTFM) parameters such as mean graft flow (MGF, ml/min), pulsatility index (PI) and diastolic filling (DF, %) have been extensively researched for internal mammary arterial or saphenous vein grafts. In our experience of using the right gastroepiploic arterial (GEA) graft for right coronary artery (RCA) grafting, we observed unique GEA graft flow waveforms. We analysed the GEA graft flow waveforms for their effectiveness in determining GEA graft patency by power spectral analysis.
  
  
  METHODS
  Forty-five patients underwent off-pump coronary artery bypass using the GEA graft for RCA grafting individually. The means of intraoperative MGF, PI and DF were compared between patent and non-patent grafts, postoperatively. Furthermore, the GEA flow data were output and analysed using power spectral analysis.
  
  
  RESULTS
  Forty grafts were 'patent' and five were 'non-patent'. There were no significant differences in the mean TTFM parameters between the patent and non-patent grafts (MGF: 22 vs 8 ml/min, respectively, P = 0.068; PI: 3.5 vs 6.5, respectively, P = 0.155; DF: 63 vs 53%, respectively, P = 0.237). Results of the power spectral analysis presented clear differences; the power spectral density (PSD) of patent grafts presented high peaks at frequency levels of 1, 2 and 3 Hz, and the non-patent graft PSD presented high peaks that were not limited to these frequencies. The PSD had a sensitivity and specificity of 80 and 87.5%, respectively.
  
  
  CONCLUSIONS
  Power spectral analysis of the GEA graft flow is useful to distinguish between non-patent and patent grafts intraoperatively. This should be used as a fourth parameter along with MGF, PI and DF.
authors.affiliation: Department of Cardiovascular Surgery, Sapporo Medical University School of Medicine, Sapporo, Japan mayuko@sapmed.ac.jp.
authors.forename: Mayuko
authors.initials: M
authors.lastname: Uehara
authors.affiliation: Department of Cardiovascular Surgery, Sapporo Medical University School of Medicine, Sapporo, Japan.
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Takagi
authors.affiliation: Department of Cardiovascular Surgery, Sapporo Medical University School of Medicine, Sapporo, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Muraki
authors.affiliation: Department of Cardiovascular Surgery, Sapporo Medical University School of Medicine, Sapporo, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Yanase
authors.affiliation: Department of Cardiovascular Surgery, Sapporo Medical University School of Medicine, Sapporo, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Tabuchi
authors.affiliation: Department of Cardiovascular Surgery, Sapporo Medical University School of Medicine, Sapporo, Japan.
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Tachibana
authors.affiliation: Department of Cardiovascular Surgery, Sapporo Medical University School of Medicine, Sapporo, Japan.
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Miyaki
authors.affiliation: Department of Cardiovascular Surgery, Sapporo Medical University School of Medicine, Sapporo, Japan.
authors.forename: Toshiro
authors.initials: T
authors.lastname: Ito
authors.affiliation: Department of Cardiovascular Surgery, Sapporo Medical University School of Medicine, Sapporo, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Higami
mesh_terms: D000368:Aged; D001783:Blood Flow Velocity; D001026:Coronary Artery Bypass / Q000379:methods; D003627:Data Interpretation, Statistical; D005260:Female; D024405:Gastroepiploic Artery / Q000000981:diagnostic imaging / Q000601:surgery*; D006439:Hemodynamics; D006801:Humans; D007432:Intraoperative Period; D008297:Male; D008991:Monitoring, Physiologic / Q000379:methods*; D011184:Postoperative Period; D011859:Radiography; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D058017:Vascular Grafting / Q000379:methods*; D014654:Vascular Patency
keywords: Gastroepiploic arterial graft; Ischaemic heart disease; Off-pump coronary artery surgery; Power spectral analysis; Transit-time flow measurement