P669 Functional remodeling of the left atrium after first acute ST-elevation myocardial infarction: a 3D echocardiography study

Abstract

Abstract Background Left atrium (LA) is a dynamic structure which is functionally coupled with the left ventricle and modulates its function in many cardiac conditions. The geometric and functional remodeling of the LA occurring early after myocardial infarction are poorly understood. Purpose We sought to evaluate the early changes in LA geometry and function occurring in survivors of a first acute ST-elevation myocardial infarction (STEMI), using three-dimensional echocardiography (3DE). Methods LA phasic volumes and strain (both longitudinal and circumferential) were measured using a dedicated automated software package in 54 patients at pre-discharge after STEMI, and in 54 age- and sex-matched healthy volunteers (controls), (figure 1). Results In STEMI patients, both maximal (LAV max) and minimal (LAV min) LA volumes were significantly larger than in controls 63 ± 15 vs. 53 ±11 ml; p = 0,002 and 38 ± 15 ml vs. 25 ± 6; p <0.0001 (respectively). Moreover, when compared to controls (Table 1). Both longitudinal (LASr) and circumferential strain reservoirs showed a significant negative correlation with peak cardiac troponin I values (r=-0.344; p = 0.007 and r=-0.357; p = 0.005, respectively) as an estimate of the extent of myocardial damage. Conclusion STEMI was associated to significant geometrical and functional remodeling of the LA which was correlated with the extent of myocardial damage. Table 1 Controls STEMI patients P-value Longitudinal% LASr 21.8 ± 8.4 13.72 ± 8.27 <0.0001 LAScd -12.8 ± 8.48 -6.43 ± 4.74 <0.0001 LASct -9.73 ± 6.04 -7.26 ± 5.87 0.05 Circumferential % LASr-c 27.31 ± 8.07 18.92 ± 9.16 <0.0001 LAScd-c -11.2 ± 5.93 -6.46 ± 5.68 0.0002 LASct-c -16.22 ± 6.33 -12.41 ± 5.94 0.004 LASr longitudinal strain reservoir, LAScd: longitudinal strain conduit, LAScd: longitudinal strain contraction, LASr-c: circumferential strain reservoir, LAScd-c: circumferential strain conduit , LASct-c:circumferential strain contraction Abstract P669 Figure 1