Correlation of Trabeculae and Papillary Muscles With Clinical and Cardiac Characteristics and Impact on CMR Measures of LV Anatomy and Function

Abstract

Objective We sought 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 cardiovascular magnetic resonance (CMR) images, obtained using a steady-state free precession sequence, from 1494 members of the Framingham Offspring cohort were analyzed using software that automatically segments TPM. Absolute TPM volume, TPM as a fraction of end-diastolic volume (TPM/EDV), and TPM mass as a fraction of LV mass (TPMm/LVM) were determined on all Offspring and in a referent group of Offspring free of clinical cardiovascular disease and hypertension. Results In the referent group (aged 61±9 years, with 262 men and 423 women) 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 (BMI). TPMm/LVM was inversely correlated with age (p<0.0001), BMI (p<0.018) and systolic blood pressure (p<0.0001). Among all 1494 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 CMR LV parameters are significantly affected by whether TPM are 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 demonstrate that TPM/EDV decreases with increasing age in both sexes, but is not related to hypertension or obesity.

Left and right ventricular parameters corrected with threshold-based quantification method in a normal cohort analyzed by three independent observers with various training-degree

“…Our data regarding the sum of papillary muscle and trabecular mass in the left ventricle was consistent with large population based literature data in all observers [10].…”

“…It is difficult to compare literature data because of the diverse evaluation of TPM volumes. The majority of prior studies presented data that was either papillary muscle or trabecular mass measurement in isolation [5][6][7][8]; few studies 1 3 are available which reported the sum of papillary and trabecular mass [9][10][11][12].…”

“…According to literature data, quantitative analysis of TPM could alter normal LV values [10,13]. Although structural and functional evaluation of RV is challenging, CMR is an accurate method to evaluate thin free wall and trabeculation of right ventricle [1].…”

Cardiac Magnetic Resonance Imaging Versus Transthoracic Echocardiography for Prediction of Outcomes in Chronic Aortic or Mitral Regurgitation

“…[23][24][25][26] Three-dimensional TTE was not used in this study, though does have some advantages over 2D-TTE and could be compared to CMR in future studies. Other limitations of this study are the modest study size and small number of primary endpoints.…”

Assessment of left ventricular mass by SPECT MPI

“…In particular, the inclusion or exclusion of trabecular myocardium in global LV mass assessment has not been standardized. 21 In the present study, 1 the investigators manually traced the epiand endocardial contours of the LV-excluding trabeculations-to determine myocardial volumes (myocardial volume = epicardial volume -endocardial volume). By multiplying myocardial volumes with the cardiac density (q = 1.05 g/mL), they obtained the LV mass.…”