title: CMR Guidance for Recanalization of Coronary Chronic Total Occlusion.
abstract: This study explored whether cardiac magnetic resonance (CMR) could help select patients who could benefit from revascularization by identifying inducible myocardial ischemia and viability in the perfusion territory of the artery with chronic total occlusion (CTO).
  
  
  
  The benefit of revascularization using percutaneous coronary intervention (PCI) in CTO is controversial. CMR offers incomparable left ventricular (LV) systolic function assessment in addition to potent ischemic burden quantification and reliable myocardial viability analysis. Whether CMR guided CTO revascularization would be helpful to such patients has not yet been explored fully.
  
  
  
  A prospective study of 50 consecutive CTO patients was conducted. Of 50 patients undergoing baseline stress CMR, 32 (64%) were selected for recanalization based on the presence of significant inducible perfusion deficit and myocardial viability within the CTO arterial territory. Patients were rescanned 3 months after successful CTO recanalization.
  
  
  
  At baseline, myocardial perfusion reserve (MPR) in the CTO territory was significantly reduced compared with the remote region (1.8 ± 0.72 vs. 2.2 ± 0.7; p = 0.01). MPR in the CTO region improved significantly after PCI (to 2.3 ± 0.9; p = 0.02 vs. baseline) with complete or near-complete resolution of CTO related perfusion defect in 90% of patients. Remote territory MPR was unchanged after PCI (2.5 ± 1.2; p = NS vs. baseline). The LV ejection fraction increased from 63 ± 13% to 67 ± 12% (p < 0.0001) and end-systolic volume decreased from 65 ± 38 to 56 ± 38 ml (p < 0.001) 3 months after CTO PCI. Importantly, despite minimal post-procedural infarction due to distal embolization and side branch occlusion in 8 of 32 patients (25%), the total Seattle Angina Questionnaire score improved from a median of 54 (range 45 to 74) at baseline to 89 (range 77 to 98) after CTO recanalization (p < 0.0001).
  
  
  
  In this small group of patients showing CMR evidence of significant myocardial inducible perfusion defect and viability, CTO recanalization reduces ischemic burden, favors reverse remodeling, and ameliorates quality of life.
authors.affiliation: Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, United Kingdom; National Heart and Lung Institute, Imperial College, London, United Kingdom; Bristol Heart Institute, Bristol NIHR Cardiovascular Biomedical Research Unit, University of Bristol, Bristol, United Kingdom.
authors.forename: Chiara
authors.initials: C
authors.lastname: Bucciarelli-Ducci
authors.affiliation: Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, United Kingdom.
authors.forename: Dominique
authors.initials: D
authors.lastname: Auger
authors.affiliation: National Heart and Lung Institute, Imperial College, London, United Kingdom; Department of Cardiology, Royal Brompton Hospital, London, United Kingdom.
authors.forename: Carlo
authors.initials: C
authors.lastname: Di Mario
authors.affiliation: Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, United Kingdom.
authors.forename: Didier
authors.initials: D
authors.lastname: Locca
authors.affiliation: Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, United Kingdom.
authors.forename: Joanna
authors.initials: J
authors.lastname: Petryka
authors.affiliation: Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, United Kingdom.
authors.forename: Rory
authors.initials: R
authors.lastname: O'Hanlon
authors.affiliation: Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, United Kingdom.
authors.forename: Agata
authors.initials: A
authors.lastname: Grasso
authors.affiliation: Department of Cardiology, Royal Brompton Hospital, London, United Kingdom.
authors.forename: Christine
authors.initials: C
authors.lastname: Wright
authors.affiliation: Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, United Kingdom.
authors.forename: Karen
authors.initials: K
authors.lastname: Symmonds
authors.affiliation: Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, United Kingdom.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Wage
authors.affiliation: Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, United Kingdom.
authors.forename: Eleni
authors.initials: E
authors.lastname: Asimacopoulos
authors.affiliation: Department of Cardiology, Royal Brompton Hospital, London, United Kingdom.
authors.forename: Francesca
authors.initials: F
authors.lastname: Del Furia
authors.affiliation: Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, United Kingdom; Department of Cardiology, Royal Brompton Hospital, London, United Kingdom.
authors.forename: Jonathan C
authors.initials: JC
authors.lastname: Lyne
authors.affiliation: Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, United Kingdom; National Heart and Lung Institute, Imperial College, London, United Kingdom.
authors.forename: Peter D
authors.initials: PD
authors.lastname: Gatehouse
authors.affiliation: National Heart and Lung Institute, Imperial College, London, United Kingdom; Department of Cardiology, Royal Brompton Hospital, London, United Kingdom.
authors.forename: Kim M
authors.initials: KM
authors.lastname: Fox
authors.affiliation: Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, United Kingdom; National Heart and Lung Institute, Imperial College, London, United Kingdom. Electronic address: d.pennell@ic.ac.uk.
authors.forename: Dudley J
authors.initials: DJ
authors.lastname: Pennell
mesh_terms: D000368:Aged; D003326:Coronary Circulation; D054059:Coronary Occlusion / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000628:therapy*; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D009206:Myocardium / Q000473:pathology; D018579:Patient Selection; D062645:Percutaneous Coronary Intervention; D011237:Predictive Value of Tests; D011446:Prospective Studies; D020127:Recovery of Function; D013318:Stroke Volume; D011795:Surveys and Questionnaires; D014022:Tissue Survival; D016896:Treatment Outcome; D016277:Ventricular Function, Left
keywords: cardiac magnetic resonance; chronic total occlusion; coronary artery disease