The unique mechanism of functional mitral regurgitation in acute myocardial infarction: a prospective dynamic 4D quantitative echocardiographic study

• DOI: 10.1093/ehjci/jey177
• Publication Date: 2018-10-31T20:14:43Z
• Authors: Toshiyuki Kimura; Véronique L Roger; Nozomi Watanabe; Sergio Barros-Gomes; Yan Topilsky; Shun Nishino; Yoshisato Shibata; Maurice Enriquez-...
• Keywords: Functional mitral regurgitation

Abstract Aims Mechanisms of chronic ischaemic mitral regurgitation (IMR) are well-characterized by apically tethered leaflet caused papillary muscles (PMs) displacement and adynamic apparatus. We investigated the unique geometry dynamics apparatus in first acute myocardial infarction (MI) using quantified 3D echocardiography. Methods results prospectively performed echocardiography 2.3 ± 1.8 days after MI, 174 matched patients with (n = 87) without IMR 87). left ventricular (LV) volumes throughout cardiac cycle was quantified. Similar quantification obtained at post-MI stage 44). Mechanistically, associated larger flatter annulus (area 9.29 1.74 cm2 vs. 8.57 1.94 cm2, P 0.002, saddle shape 12.7 4.5% 15.0 4.6%, 0.001), tenting (length 6.36 1.78 mm 5.60 1.55 mm, 0.003) but displayed smaller alterations (all < 0.01) annular size, PM movement remained dynamic 0.01). Specific to IMR, apical (P > 0.70), greater separation (21.7 4.9 20.0 3.4 0.01), widest angulation (38.4 6.2° for moderate 33.5 7.3° mild 31.4 6.3° no-IMR, 0.0009) wider MI Conclusions provides insights into 4D IMR. Mitral distinct mechanism is not seen excess deforming valve, probably because sudden-onset regional wall motion abnormality apparent global LV remodelling. This specific should be considered novel therapeutic strategies complicating MI.