Discussion
LACI, cardiac functional failure
AMI
The aim of this work was to assess a novel CMR-derived LACI and confirm its prognostic value in a large cohort of patients with AMI.Recently, LACI was defined and proven to possess prognostic value as well as to improve risk classifications in the multi-ethnic population of the MESA study. Likewise, the results of our study demonstrated prognostic implications of this novel index in a large AMI patient cohort. Especially in patients at high-risk according to reduced LVEF LACI evaluation enabled further risk stratification and therefore could optimize clinical patient management.While commonly used volumetric analyses largely disregard the atrioventricular interplay, a combination of simultaneous LA and LV EDV measurements expressed by LACI can be suggested to allow evaluation of the holistic cardiac performance more accurately.Currently, many guideline recommendations and clinical decisions (e.g. for ICD device therapy) are mainly based on a LVEF cut-off of 35% which alone may not be sufficient for this purpose [Of note, the identified cut-off value of the current study was considerably higher than reported in previous literature [Since a greater LACI suggests an increased mismatch with a disproportionately enlarged LA in relation to LV, this index represents a simple approach to unmask several pathophysiological mechanisms of cardiac performance. LA size is considered as an appropriate barometer of LV filling pressure [It is noteworthy, that the alternatively calculated LACI ES showed no association with MACE in our study cohort, which, however, is in line with previous findings of the MESA study [Similar to the calculation of LACI, first imaging studies already applied and implemented functional deformation assessments to evaluate the atrioventricular interplay for optimized diagnostic and prognostic purposes [However, although LACI assessment per se cannot replace or achieve a similar level of prognostic power like LA or LV strain parameters can provide, it is important to consider its role as an index parameter measuring atrioventricular proportions and a growing volumetric mismatch could indicate an aspect of cardiac functional failure that might not be adequately captured by (isolated) LA and/or LV strain deterioration. Consequently, not only amongst LA and LV volumetric analyses but also in addition to strain measurements LACI calculation could give clinicians additional prognostic data to identify patients at higher risk for MACE.Of note, deformation imaging relies on accurate data acquisition and compared to LACI calculation time-consuming post-processing [