title: Correlation of trabeculae and papillary muscles with clinical and cardiac characteristics and impact on CMR measures of LV anatomy and function.
abstract: OBJECTIVE
  The goal of this study was to assess the relationship of left ventricular (LV) trabeculae and papillary muscles (TPM) with clinical characteristics in a community-based, free-living adult cohort and to determine the effect of TPM on quantitative measures of LV volume, mass, and ejection fraction (EF).
  
  
  BACKGROUND
  Hypertrabeculation has been associated with adverse cardiovascular events, but the distribution and clinical correlates of the volume and mass of the TPM in a normal left ventricle have not been well characterized.
  
  
  METHODS
  Short-axis cine cardiac magnetic resonance images, obtained using a steady-state free precession sequence from 1,494 members of the Framingham Heart Study Offspring cohort, were analyzed with software that automatically segments TPM. Absolute TPM volume, TPM as a fraction of end-diastolic volume (EDV) (TPM/EDV), and TPM mass as a fraction of LV mass were determined in all offspring and in a referent group of offspring free of clinical cardiovascular disease and hypertension.
  
  
  RESULTS
  In the referent group (mean age 61 ± 9 years; 262 men and 423 women), mean TPM was 23 ± 3% of LV EDV in both sexes (p = 0.9). TPM/EDV decreased with age (p < 0.02) but was not associated with body mass index. TPM mass as a fraction of LV mass was inversely correlated with age (p < 0.0001), body mass index (p < 0.018), and systolic blood pressure (p < 0.0001). Among all 1,494 participants (699 men), LV volumes decreased 23%, LV mass increased 28%, and EF increased by 7.5 EF units (p < 0.0001) when TPM were considered myocardial mass rather than part of the LV blood pool.
  
  
  CONCLUSIONS
  Global cardiac magnetic resonance LV parameters were significantly affected by whether TPM was considered as part of the LV blood pool or as part of LV mass. Our cross-sectional data from a healthy referent group of adults free of clinical cardiovascular disease demonstrated that TPM/EDV decreases with increasing age in both sexes but is not related to hypertension or obesity.
authors.affiliation: NHLBI's Framingham Heart Study, Framingham, Massachusetts, USA.
authors.forename: Michael L
authors.initials: ML
authors.lastname: Chuang
authors.forename: Philimon
authors.initials: P
authors.lastname: Gona
authors.forename: Gilion L T F
authors.initials: GL
authors.lastname: Hautvast
authors.forename: Carol J
authors.initials: CJ
authors.lastname: Salton
authors.forename: Susan J
authors.initials: SJ
authors.lastname: Blease
authors.forename: Susan B
authors.initials: SB
authors.lastname: Yeon
authors.forename: Marcel
authors.initials: M
authors.lastname: Breeuwer
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: O'Donnell
authors.forename: Warren J
authors.initials: WJ
authors.lastname: Manning
mesh_terms: D000367:Age Factors; D000368:Aged; D001794:Blood Pressure; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005260:Female; D006352:Heart Ventricles / Q000033:anatomy & histology*; D006801:Humans; D006973:Hypertension / Q000473:pathology / Q000503:physiopathology; D007090:Image Interpretation, Computer-Assisted; D016014:Linear Models; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D010210:Papillary Muscles / Q000033:anatomy & histology* / Q000502:physiology*; D011237:Predictive Value of Tests; D012016:Reference Values; D015203:Reproducibility of Results; D012737:Sex Factors; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000473:pathology / Q000503:physiopathology; D016277:Ventricular Function, Left