title: The Potential Impact of Functional Imaging on Decision Making and Outcome in Patients Undergoing Surgical Revascularization.
abstract: OBJECTIVE
  Coronary angiography (CA) remains the standard for preoperative planning for surgical revascularization. However, besides anatomical imaging, current guidelines recommend additional functional imaging before a therapy decision is made. We assess the impact of functional imaging on the strategy of coronary artery bypass grafting (CABG) with particular regards on postoperative patency and myocardial perfusion.
  
  
  METHODS
  After CA, 55 patients (47 males/8 females; age: 65.1 ± 9.5 years) underwent perfusion cardiovascular magnetic resonance (CMR) and dual-source computed tomography (DSCT) before isolated CABG (n = 31), CABG and concomitant valve surgery (valve + CABG; n = 10) and isolated valve surgery (n = 14; control). DSCT was used for analysis of significant stenosis, CMR for myocardial-perfusion to discriminate between: no ischemia (normal), ischemia, or scar. The results, unknown to the surgeons, were compared with CA and related to the location and number of distal anastomoses. Nineteen CABG patients underwent follow-up CMR and DSCT (FU: 13 ± 3 months) to compare the preop findings with the postop outcomes.
  
  
  RESULTS
  Thirty-nine patients either received CABG alone (n = 31) or a combined procedure (n = 10) with a total of 116 distal anastomoses. DSCT was compared with CA regarding accuracy of coronary stenosis and showed 91% sensitivity, 88% specificity, and negative/positive predictive values of 89/90%. In total, 880 myocardial segments (n = 55, 16 segments/patient) were assessed by CMR. In 17% (149/880) of segments ischemia and in 8% (74/880) scar tissue was found. Interestingly, 14% (16/116) of bypass-anastomoses were placed on non-ischemic myocardium and 3% (4/116) on scar tissue. In a subgroup of 19 patients 304 segments were evaluated. Thirty-nine percent (88/304) of all segments showed ischemia preoperatively, while 94% (83/88) of these ischemic segments did not show any ischemia postoperatively. In regard to performed anastomoses, 79% of all grafts (49/62) were optimally placed, whereas 21% (13/62) were either placed into non-ischemic myocardium or scar tissue, including 10% occluded grafts (6/62).
  
  
  CONCLUSIONS
  In the whole cohort analysis, 17% of grafts were placed in regions with either no ischemia or scar tissue. The subgroup analysis revealed that 94% of all ischemic segments were successfully revascularized after CABG. Thus, functional imaging could be a promising tool in preoperative planning of revascularization strategy. Avoidance of extensive and unnecessary grafting could further optimize outcomes after CABG.
authors.affiliation: Clinic for Cardiac Surgery, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Andre
authors.initials: A
authors.lastname: Plass
authors.affiliation: Institute for Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Robert P
authors.initials: RP
authors.lastname: Goetti
authors.affiliation: Clinic for Cardiac Surgery, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Maximilian Y
authors.initials: MY
authors.lastname: Emmert
authors.affiliation: Clinic for Cardiac Surgery, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Etem
authors.initials: E
authors.lastname: Caliskan
authors.affiliation: Institute for Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Paul
authors.initials: P
authors.lastname: Stolzmann
authors.affiliation: Clinic for Cardiac Surgery, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Monika
authors.initials: M
authors.lastname: Wieser
authors.affiliation: Institute for Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Olivio
authors.initials: O
authors.lastname: Donati
authors.affiliation: Institute for Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Hatem
authors.initials: H
authors.lastname: Alkadhi
authors.affiliation: Clinic for Cardiac Surgery, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Volkmar
authors.initials: V
authors.lastname: Falk
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D017023:Coronary Angiography; D001026:Coronary Artery Bypass / Q000009:adverse effects; D003324:Coronary Artery Disease / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*; D023921:Coronary Stenosis / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*; D003661:Decision Support Techniques; D003952:Diagnostic Imaging / Q000379:methods*; D005260:Female; D006349:Heart Valve Diseases / Q000150:complications / Q000175:diagnosis / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging; D018579:Patient Selection; D011237:Predictive Value of Tests; D012307:Risk Factors; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014654:Vascular Patency