title: Biventricular myocardial strain analysis in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) using cardiovascular magnetic resonance feature tracking.
abstract: BACKGROUND
  Fibrofatty degeneration of myocardium in ARVC is associated with wall motion abnormalities. The aim of this study was to examine whether Cardiovascular Magnetic Resonance (CMR) based strain analysis using feature tracking (FT) can serve as a quantifiable measure to confirm global and regional ventricular dysfunction in ARVC patients and support the early detection of ARVC.
  
  
  METHODS
  We enrolled 20 patients with ARVC, 30 with borderline ARVC and 22 subjects with a positive family history but no clinical signs of a manifest ARVC. 10 healthy volunteers (HV) served as controls. 15 ARVC patients received genotyping for Plakophilin-2 mutation (PKP-2), of which 7 were found to be positive. Cine MR datasets of all subjects were assessed for myocardial strain using FT (TomTec Diogenes Software). Global strain and strain rate in radial, circumferential and longitudinal mode were assessed for the right and left ventricle. In addition strain analysis at a segmental level was performed for the right ventricular free wall.
  
  
  RESULTS
  RV global longitudinal strain rates in ARVC (-0.68 ± 0.36 sec⁻¹) and borderline ARVC (-0.85 ± 0.36 sec⁻¹) were significantly reduced in comparison with HV (-1.38 ± 0.52 sec⁻¹, p ≤ 0.05). Furthermore, in ARVC patients RV global circumferential strain and strain rates at the basal level were significantly reduced compared with HV (strain: -5.1 ± 2.7 vs. -9.2 ± 3.6%; strain rate: -0.31 ± 0.13 sec(-1) vs. -0.61 ± 0.21 sec⁻¹). Even for patients with ARVC or borderline ARVC and normal RV ejection fraction (n=30) global longitudinal strain rate proved to be significantly reduced compared with HV (-0.9 ± 0.3 vs. -1.4 ± 0.5 sec(-1); p < 0.005). In ARVC patients with PKP-2 mutation there was a clear trend towards a more pronounced impairment in RV global longitudinal strain rate. On ROC analysis RV global longitudinal strain rate and circumferential strain rate at the basal level proved to be the best discriminators between ARVC patients and HV (AUC: 0.9 and 0.92, respectively).
  
  
  CONCLUSIONS
  CMR based strain analysis using FT is an objective and useful measure for quantification of wall motion abnormalities in ARVC. It allows differentiation between manifest or borderline ARVC and HV, even if ejection fraction is still normal.
authors.affiliation: Department of Clinical Radiology, University Hospital of Muenster, Albert-Schweitzer-Campus 1, 48149, Münster, Germany. philipp.heermann@ukmuenster.de.
authors.forename: Philipp
authors.initials: P
authors.lastname: Heermann
authors.affiliation: Department of Radiology, University Hospital of Cologne, Cologne, Germany. dennis.hedderich@uk-koeln.de.
authors.forename: Dennis M
authors.initials: DM
authors.lastname: Hedderich
authors.affiliation: Department of Cardiology, University Hospital of Muenster, Münster, Germany. matthias.paul@ukmuenster.de.
authors.forename: Matthias
authors.initials: M
authors.lastname: Paul
authors.affiliation: Department of Clinical Radiology, University Hospital of Muenster, Albert-Schweitzer-Campus 1, 48149, Münster, Germany. schuelke@uni-muenster.de.
authors.forename: Christoph
authors.initials: C
authors.lastname: Schülke
authors.affiliation: Department of Radiology, University Hospital of Cologne, Cologne, Germany. jan.kroeger@uk-koeln.de.
authors.forename: Jan Robert
authors.initials: JR
authors.lastname: Kroeger
authors.affiliation: Department of Radiology, University Hospital of Cologne, Cologne, Germany. bettina.baessler@uk-koeln.de.
authors.forename: Bettina
authors.initials: B
authors.lastname: Baeßler
authors.affiliation: Department of Cardiology, Niels-Stensen-Kliniken, Marienhospital Osnabrueck, Osnabrueck, Germany. thomas.wichter@mho.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Wichter
authors.affiliation: Department of Clinical Radiology, University Hospital of Muenster, Albert-Schweitzer-Campus 1, 48149, Münster, Germany. david.maintz@uk-koeln.de.|Department of Radiology, University Hospital of Cologne, Cologne, Germany. david.maintz@uk-koeln.de.
authors.forename: David
authors.initials: D
authors.lastname: Maintz
authors.affiliation: Department of Cardiology, University Hospital of Muenster, Münster, Germany. Johannes.Waltenberger@ukmuenster.de.
authors.forename: Johannes
authors.initials: J
authors.lastname: Waltenberger
authors.affiliation: Department of Clinical Radiology, University Hospital of Muenster, Albert-Schweitzer-Campus 1, 48149, Münster, Germany. heindel@uni-muenster.de.
authors.forename: Walter
authors.initials: W
authors.lastname: Heindel
authors.affiliation: Department of Clinical Radiology, University Hospital of Muenster, Albert-Schweitzer-Campus 1, 48149, Münster, Germany. alexander.bunck@uk-koeln.de.|Department of Radiology, University Hospital of Cologne, Cologne, Germany. alexander.bunck@uk-koeln.de.
authors.forename: Alexander C
authors.initials: AC
authors.lastname: Bunck
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D019540:Area Under Curve; D019571:Arrhythmogenic Right Ventricular Dysplasia / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology; D001696:Biomechanical Phenomena; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D011237:Predictive Value of Tests; D012372:ROC Curve; D012189:Retrospective Studies; D013314:Stress, Mechanical; D013318:Stroke Volume; D016277:Ventricular Function, Left; D016278:Ventricular Function, Right; D055815:Young Adult