title: Changes of left ventricular mechanics after trans-catheter aortic valve implantation and surgical aortic valve replacement for severe aortic stenosis: A tissue-tracking cardiac magnetic resonance study.
abstract: BACKGROUND
  Left ventricular (LV) mechanics are impaired in patients with severe aortic stenosis (AS). The aim of the present study was to assess their changes early and late after trans-catheter aortic valve implantation (TAVI) and surgical aortic valve replacement (AVR) using cardiac magnetic resonance (CMR) tissue-tracking imaging.
  
  
  METHODS
  In 59 patients with severe AS undergoing either TAVI (n=35) or surgical AVR (n=24), CMR with late gadolinium enhancement (LGE) imaging was performed before and early post-procedure to evaluate LV function and mass, and presence/extent of LGE. A third CMR scan was performed in 29 patients after a mean follow-up of 15±4months. Tissue-tracking analysis was applied to cine CMR images, to assess LV global longitudinal (GLS), circumferential (GCS) and radial (GRS) strains.
  
  
  RESULTS
  The TAVI and surgical AVR groups were similar with respect to baseline (p=0.14) and early post-procedure (p=0.16) LV ejection fraction. However, baseline LV GLS was significantly impaired in TAVI patients compared to surgical AVR patients (p=0.025). Early post-procedure, TAVI resulted in a significant improvement of LV GLS (p=0.003), while a significant worsening of LV GLS was observed early after surgical AVR (p=0.012). At longer term follow-up, both TAVI and surgical AVR groups experienced a significant reduction of LV mass and a significant improvement of LV myocardial mechanics in all the three directions.
  
  
  CONCLUSIONS
  Treatment-specific differences in the changes of LV myocardial mechanics early after afterload release by TAVI and surgical AVR are present. Later, both interventions are associated with an improvement of LV myocardial deformation, alongside a regression of LV hypertrophy.
authors.affiliation: Department of Hearth Health, South Australian Health & Medical Research Institute, Adelaide, Australia; Flinders University, Bedford Park, Adelaide, Australia. Electronic address: gaetano.nucifora@sahmri.com.
authors.forename: Gaetano
authors.initials: G
authors.lastname: Nucifora
authors.affiliation: Department of Hearth Health, South Australian Health & Medical Research Institute, Adelaide, Australia; Department of Cardiovascular Medicine, Flinders Medical Centre, Bedford Park, Adelaide, Australia; Flinders University, Bedford Park, Adelaide, Australia.
authors.forename: John-Paul
authors.initials: JP
authors.lastname: Tantiongco
authors.affiliation: Department of Cardiovascular Medicine, Flinders Medical Centre, Bedford Park, Adelaide, Australia; Flinders University, Bedford Park, Adelaide, Australia.
authors.forename: Gareth
authors.initials: G
authors.lastname: Crouch
authors.affiliation: Department of Cardiovascular Medicine, Flinders Medical Centre, Bedford Park, Adelaide, Australia; Flinders University, Bedford Park, Adelaide, Australia.
authors.forename: Jayme
authors.initials: J
authors.lastname: Bennetts
authors.affiliation: Department of Cardiovascular Medicine, Flinders Medical Centre, Bedford Park, Adelaide, Australia; Flinders University, Bedford Park, Adelaide, Australia.
authors.forename: Ajay
authors.initials: A
authors.lastname: Sinhal
authors.affiliation: Department of Cardiovascular Medicine, Flinders Medical Centre, Bedford Park, Adelaide, Australia; Flinders University, Bedford Park, Adelaide, Australia.
authors.forename: Phillip J
authors.initials: PJ
authors.lastname: Tully
authors.affiliation: Department of Cardiovascular Medicine, Flinders Medical Centre, Bedford Park, Adelaide, Australia.
authors.forename: Craig
authors.initials: C
authors.lastname: Bradbrook
authors.affiliation: Department of Cardiovascular Medicine, Flinders Medical Centre, Bedford Park, Adelaide, Australia; Flinders University, Bedford Park, Adelaide, Australia.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Baker
authors.affiliation: Department of Hearth Health, South Australian Health & Medical Research Institute, Adelaide, Australia; Department of Cardiovascular Medicine, Flinders Medical Centre, Bedford Park, Adelaide, Australia; Flinders University, Bedford Park, Adelaide, Australia.
authors.forename: Joseph B
authors.initials: JB
authors.lastname: Selvanayagam
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000601:surgery; D015331:Cohort Studies; D017023:Coronary Angiography; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D013997:Time Factors; D065467:Transcatheter Aortic Valve Replacement; D016896:Treatment Outcome; D016277:Ventricular Function, Left / Q000502:physiology*
keywords: Aortic stenosis; Cardiac magnetic resonance; Fibrosis; Hypertrophy; Myocardial mechanics; Tissue-tracking