Myocardial strain is regulated by cardiac preload in the early stage of sepsis

Abstract

Abstract Background: Owing to a lack of data，this study aimed to explore the effect of cardiac preload on myocardial strain in septic patients. Methods: A total of 70 septic patients in intensive care unit (ICU) of a tertiary teaching hospital in China from January 2018 to July 2019 and underwent transthoracic echocardiography were enrolled. Echocardiographic data were recorded at ICU admission and 24 hours later. Patients were assigned to low left ventricular end-diastolic volume index (LVEDVI) and normal LVEDVI groups. We assessed the impact of preload on myocardial strain between the groups and analyzed the correlation of echocardiographic parameters under different preload conditions. Results: Thirty-seven patients (53%) had a low LVEDVI and 33 (47%) a normal LVEDVI. Those in the low LVEDVI group had a faster heart rate and required a greater degree of fluid infusion. The left ventricular global strain (LVGLS)(-8.6 to -10.80), left ventricular global circumferential strain (LVGCS) (-13.83 to -18.26), and right ventricular global longitudinal strain (RVGLS) (-6.9 to -10.60) showed significant improvements in the low LVEDVI group after fluid resuscitation. However, fluid resuscitation resulted in a significantly increased cardiac afterload value only in the normal LVEDVI group. Multivariate backward linear regression showed that LVEDVI changes were independently associated with myocardial strain-related improvements during fluid resuscitation. In the correlation matrix, the baseline LVGLS, LVGCS, and RVGLS showed strong interdependence in the low LVEDVI group, and higher tricuspid annular plane systolic excursion was negatively correlated with lower myocardial strain. The baseline LVEDVI was significantly negatively correlated with the LVGLS and RVGLS but not LVGCS. LVEDVI increases during fluid resuscitation were associated with improvements in the myocardial strain degree. Conclusions: Myocardial strain alterations were significantly influenced by the cardiac preload during fluid resuscitation in sepsis.