The role of false tendons in left ventricular remodeling and secondary mitral regurgitation after acute myocardial infarction

Abstract

BACKGROUND: Left ventricular false tendons (LVFT) are common structures visualized on transthoracic echocardiography (TTE). The present study tested the hypothesis that LVFT, via a possible ‘constraint’ mechanism, attenuate left ventricular (LV) remodeling and secondary mitral regurgitation after acute myocardial infarction. METHODS: Seventy-one patients admitted to the Coronary Care Unit following an ST-elevation (n = 63) or non-ST-elevation (n = 8) myocardial infarction were analyzed; 29 (41%) had LVFT, and 42 (59%) did not (no-LVFT). All had a TTE and at least 1 follow-up study after revascularization. The χ2 analysis, Student's t-test, and Mann Whitney U test were used for the statistical analyses. RESULTS: The mean age (64 vs. 66 years), left ventricular ejection fraction (LVEF) (41% vs. 39%), left ventricular end-diastolic diameter (LVEDd) index (23 mm/m2 for both), and prevalence of ≥ moderate secondary/functional mitral regurgitation (MR) (17% vs. 14%) were similar between the LVFT and no-LVFT groups. At 1-year follow-up, there was no significant difference in chamber remodeling amongst the LVFT versus no-LVFT group when assessed by: 1) ≥ 10% decrease in the relative LVEF (24% vs. 26%; p = 0.83); 2) ≥ 10% increase in the LVEDd index (41% vs. 38%, p = 0.98); and, 3) ≥ 10% increase in the LV mass index (48% vs. 41%, p = 0.68). There was no difference in the prevalence of ≥ moderate secondary/ functional MR (17% vs. 12%, p = 0.77). Outcomes remained similar when stratifying by LVFT morphology or ischemic territory. CONCLUSIONS: In patients with mild to moderate LV dysfunction and normal chamber size, LVFT do not affect the development of LV remodeling or secondary/functional MR postmyocardial infarction.