Insight into hypertrophied hearts: a cardiovascular magnetic resonance study of papillary muscle mass and T1 mapping

Research output: Contribution to journalArticlepeer-review

Authors

  • Rebecca Kozor
  • Sabrina Nordin
  • Thomas A Treibel
  • Stefania Rosmini
  • Silvia Castelletti
  • And 9 others
  • Marianna Fontana
  • Gabriella Captur
  • Shanat Baig
  • Richard P Steeds
  • Derralynn Hughes
  • Charlotte Manisty
  • Stuart M Grieve
  • Gemma A Figtree
  • James C Moon

Colleges, School and Institutes

External organisations

  • Barts Heart Centre, London, UK Sydney Medical School, University of Sydney, Sydney, Australia rebeccakozor@gmail.com.
  • University College London
  • Barts Heart Centre, London, UK.
  • National Amyloidosis Centre, Royal Free Hospital, University College London, London, UK.
  • University Hospitals Birmingham
  • Sydney Medical School, University of Sydney, Sydney, Australia.

Abstract

AIMS: Left ventricular papillary muscles (LVPM) can appear disproportionately hypertrophied, particularly in Fabry disease (FD) where storage appears detectable by cardiovascular magnetic resonance (CMR) T1 mapping. The aim of the study was to measure LVPM mass in heart diseases with left ventricular hypertrophy (LVH) and to gain insight into the mechanisms of LVPM hypertrophy in FD.

METHODS AND RESULTS: Four hundred and seventy-eight cases were retrospectively recruited: 125 FD, 85 hypertrophic cardiomyopathy (HCM), 67 amyloid, 82 aortic stenosis (AS), 40 hypertension, 79 controls. LVPM contribution to LVM was manually contoured on CMR short axis cines. T1 values (septal, LVPM) were measured using ShMOLLI sequences in FD and controls. LVPM contribution to LVM was highest in LVH+ve FD and significantly increased compared to all other LVH+ve groups (FD 13 ± 3%, HCM 10 ± 3%, amyloid 8 ± 2%, AS 7 ± 3%, hypertension 7 ± 2%, controls 7 ± 1%; P < 0.001). LVH+ve HCM also had significantly increased LVPM. In LVH-ve cohorts, only FD had significantly increased LVPM (11 ± 3%; P < 0.001). In FD there was concordant septal and LVPM T1. LVH+ve FD: when septal T1 was low, LVPM T1 was low in 90%. LVH-ve FD: when septal T1 was normal, LVPM T1 was normal in 70% (indicating no detectable storage); when septal T1 was low, 75% had low LVPM T1 (indicating storage). LVPM hypertrophy was similar between the low and normal septal T1 groups (11 ± 3% vs. 10 ± 3%, P = 0.08).

CONCLUSION: Disproportionate hypertrophy of LVPMs in LVH+ve hearts occurred in FD and HCM. This phenomenon also occurred in LVH-ve FD. Low T1 was not always present in FD LVPM hypertrophy, implying additional mechanisms activating hypertrophy signalling pathways.

Details

Original languageEnglish
Pages (from-to)1034–1040
JournalEuropean Heart Journal Cardiovascular Imaging
Volume18
Issue number9
Publication statusPublished - 2 Sep 2016

Keywords

  • Journal Article