The Role of False Tendons in Left Ventricular Remodeling and Secondary Mitral Regurgitation After Acute Myocardial Infarction.

Abstract

BACKGROUNDLeft 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.METHODSSeventy-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.RESULTSThe 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.CONCLUSIONSIn patients with mild to moderate LV dysfunction and normal chamber size, LVFT do not affect the development of LV remodeling or secondary/functional MR post-myocardial infarction.