title: Time-resolved tracking of the atrioventricular plane displacement in Cardiovascular Magnetic Resonance (CMR) images.
abstract: Atrioventricular plane displacement (AVPD) is an indicator for systolic and diastolic function and accounts for 60% of the left ventricular, and 80% of the right ventricular stroke volume. AVPD is commonly measured clinically in echocardiography as mitral and tricuspid annular plane systolic excursion (MAPSE and TAPSE), but has not been applied widely in cardiovascular magnetic resonance (CMR). To date, there is no robust automatic algorithm available that allows the AVPD to be measured clinically in CMR with input in a single timeframe. This study aimed to develop, validate and provide a method that automatically tracks the left and right ventricular AVPD in CMR images, which can be used in the clinical setting or in applied cardiovascular research in multi-center studies.
  
  
  
  The proposed algorithm is based on template tracking by normalized cross-correlation combined with a priori information by principal component analysis. The AVPD in each timeframe is calculated for the left and right ventricle separately using CMR long-axis cine images of the 2, 3, and 4-chamber views. The algorithm was developed using a training set (n = 40), and validated in a test set (n = 113) of healthy subjects, athletes, and patients after ST-elevation myocardial infarction from 10 centers. Validation was done using manual measurements in end diastole and end systole as reference standard. Additionally, AVPD, peak emptying velocity, peak filling velocity, and atrial contraction was validated in 20 subjects, where time-resolved manual measurements were used as reference standard. Inter-observer variability was analyzed in 20 subjects.
  
  
  
  In end systole, the difference between the algorithm and the reference standard in the left ventricle was (mean ± SD) -0.6 ± 1.9 mm (R = 0.79), and -0.8 ± 2.1 mm (R = 0.88) in the right ventricle. Inter-observer variability in end systole was -0.6 ± 0.7 mm (R = 0.95), and -0.5 ± 1.4 mm (R = 0.95) for the left and right ventricle, respectively. Validation of peak emptying velocity, peak filling velocity, and atrial contraction yielded lower accuracy than the displacement measures.
  
  
  
  The proposed algorithm show good agreement and low bias with the reference standard, and with an agreement in parity with inter-observer variability. Thus, it can be used as an automatic method of tracking and measuring AVPD in CMR.
authors.affiliation: Department of Clinical Physiology, Lund University, Skane University Hospital, Lund, Sweden.|Department of Numerical Analysis, Faculty of Engineering, Lund University, Lund, Sweden.|Department of Biomedical Engineering, Faculty of Engineering, Lund University, Lund, Sweden.
authors.forename: Felicia
authors.identifier: 0000-0003-3074-5380
authors.initials: F
authors.lastname: Seemann
authors.affiliation: Department of Clinical Physiology, Lund University, Skane University Hospital, Lund, Sweden.
authors.forename: Ulrika
authors.initials: U
authors.lastname: Pahlm
authors.affiliation: Department of Clinical Physiology, Lund University, Skane University Hospital, Lund, Sweden.|Department of Health Sciences, Physiotherapy, Lund University, Lund, Sweden.
authors.forename: Katarina
authors.initials: K
authors.lastname: Steding-Ehrenborg
authors.affiliation: Department of Clinical Physiology, Lund University, Skane University Hospital, Lund, Sweden.
authors.forename: Ellen
authors.initials: E
authors.lastname: Ostenfeld
authors.affiliation: Department of Cardiology, Clinical Sciences, Lund University, Lund, Sweden.
authors.forename: David
authors.initials: D
authors.lastname: Erlinge
authors.affiliation: Assistance Publique Hôpitaux de Paris, Hôpital Henri Mondor, Créteil, France.
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Dubois-Rande
authors.affiliation: Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark.
authors.forename: Svend Eggert
authors.initials: SE
authors.lastname: Jensen
authors.affiliation: Department of Cardiology B, Oslo University Hospital Ullevål and Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: Dan
authors.initials: D
authors.lastname: Atar
authors.affiliation: Department of Clinical Physiology, Lund University, Skane University Hospital, Lund, Sweden.
authors.forename: Håkan
authors.initials: H
authors.lastname: Arheden
authors.affiliation: Department of Clinical Physiology, Lund University, Skane University Hospital, Lund, Sweden.
authors.forename: Marcus
authors.initials: M
authors.lastname: Carlsson
authors.affiliation: Department of Clinical Physiology, Lund University, Skane University Hospital, Lund, Sweden. einar.heiberg@med.lu.se.|Department of Biomedical Engineering, Faculty of Engineering, Lund University, Lund, Sweden. einar.heiberg@med.lu.se.
authors.forename: Einar
authors.initials: E
authors.lastname: Heiberg
mesh_terms: D000368:Aged; D000465:Algorithms; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging*; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D015588:Observer Variation; D025341:Principal Component Analysis
keywords: Atrioventricular plane displacement; Automated tracking; Cardiac valve displacement; Normalized cross-correlation; Principal component analysis