The Relationship of Left Ventricular Trabeculation to Ventricular Function and Structure Over a 9.5-Year Follow-Up: The MESA Study

Study Questions:

In population-representative subjects, is excessive left ventricular (LV) trabeculation associated with preceding changes in cardiac volumes and function?

Methods:

The extent of LV trabeculation, expressed as the ratio of noncompacted to compacted (NC/C) myocardium, was measured on cardiac magnetic resonance (CMR) long-axis cine images in 2,742 subjects in the MESA (Multi-Ethnic Study of Atherosclerosis) study (mean age 68.7 years, 52.3% women, 56.4% with hypertension, 16.8% with diabetes) at exam number 5. Data were considered in quintiles of trabeculation extent, with quintile 5 NC/C = 2.46 - 5.41. The relationship between maximal NC/C ratio and preceding change (9.5 years between exam 1 and 5) in LV end-systolic volume indexed to body surface area (ESVi) was determined. Secondary analyses assessed the associations between maximal NC/C and preceding changes in end-diastolic volume indexed to body surface area (EDVi) and LV ejection fraction (EF).

Results:

Over 9.5 years, ESVi decreased by 1.3 ml/m2, EDVi decreased by 5.1 ml/m2, and EF decreased by 0.6% (p < 0.0001). There were no clinically relevant differences in temporal change in LV volumes and systolic function between quintiles of trabeculation extent, including among subjects with excessive trabeculation.

Conclusions:

Greater extent of, and even excessive, LV trabeculation, measured in end-diastole in asymptomatic population-representative individuals, appears benign and is not associated with deterioration in LV volumes or function over an almost 10-year interval.

Perspective:

LV trabeculation is highly variable between individuals, and increased trabeculation is noted in some diseases (including congenital heart disease and dilated cardiomyopathies). However, the significance of prominent LV trabeculation in a general population is unknown. These data suggest that the presence of increased LV trabeculation is not associated with preceding changes in either LV size or LV systolic function. Although patients in the trial underwent CMR at an earlier time interval, the earlier exams were not adequate to assess LV NC/C ratio; as such, the study does not address whether increased LV trabeculation could herald a subsequent change in the LV. However, the data as presented provide some reassurance that ongoing follow-up or pharmacotherapy is not necessarily warranted in the setting of an isolated incidental finding of increased LV trabeculation.

Clinical Topics: Heart Failure and Cardiomyopathies, Prevention, Hypertension

Keywords: Body Surface Area, Follow-Up Studies, Ventricular Function, Left, Cardiac Volume, Myocardium, Magnetic Resonance Spectroscopy, Heart Ventricles, Hypertension, Diabetes Mellitus, Cardiomyopathy, Dilated


< Back to Listings