Associations among left ventricular systolic function, tachycardia, and cardiac preload in septic patients

Abstract Background Cardiac dysfunction is a critical component that has been discovered as being connected with sepsis-induced multi-organ failure. This disorder is related to various adverse effects and a greater death rate. Objective A previous study has investigated the association between left ventricular (LV) systolic function, tachycardia, and cardiac preload in patients with sepsis [1]. However, substantial advances in echocardiographic imaging over the past decade together with the adoption of the sepsis − 3 (2016) diagnostic criteria, have changed the assessment and characterization of septic patients. Consequently, previous findings require re-evaluation using contemporary diagnostic criteria and more sensitive measures of myocardial function. The present study aimed to re-assess the association between the LV systolic function, tachycardia, and cardiac preload in septic patients. The LV systolic function was assessed using two-dimensional speckle-tracking echocardiography -derived global LV longitudinal strain (GLS). GLS was calculated as the average peak longitudinal strain obtained from the three standard apical views: the apical four-chamber, two-chamber, and three chamber views. Patients were enrolled according to the sepsis − 3 (2016) diagnostic criteria, resulting in the inclusion of patients at an earlier stage of illness and with lower disease severity than those included in earlier studies. In addition, this study also aimed to evaluate the diagnostic utility of GLS as a sensitive marker of LV systolic dysfunction in an Egyptian population with sepsis. Methods This prospective observational research has been performed on 50 cases aged > 18 years old, both genders, clinically suspected infection, sepsis or septic shock. Transthoracic echocardiography(TTE) was usually conducted for cases had sepsis or septic shock at 2–4 h after ICU admission. Global longitudinal strain has been measured independently from preload assessment. We described abnormal strain as over − 17% (greater numbers are worse) (the more positive, the more impaired function). The ratio of the early diastolic mitral inflow velocity (E) to the early diastolic mitral annulus velocity (E/e′) was used to determine the left ventricular preload. This ratio was used to define cardiac preload. In our definition, a low preload state is described as an E/e′ value that is below eight, a high-preload status is described as above fourteen, and an intermediate-preload state is described as 8–14. Cases have been separated into three groups: Group A (number = 9): low preload state ratio of early diastolic mitral inflow blood velocity to early diastolic mitral annular tissue velocity (E/e′) < 8, group B ( n = 21): intermediate-preload state 8 ≤ E/e′ ≤ 14 and group C ( n = 21): high preload state E/e′ >14. We added a subclassification, the studied cases were subdivided according to strain into two groups: Group 1 (normal strain). Group 2 (abnormal strain). Results Between all the study patients; E/e′ ratio showed significant direct moderate correlations with heart rate, stroke volume, and global longitudinal strain (GLS). Between all the study patients : GLS showed significant direct moderate correlations with heart rate and vasopressor dose. GLS showed significant direct strong correlation with Acute physiology and chronic health (APACHE) II score. In comparison of outcomes between cases according to strain : cases with abnormal strain (group 2) had statistically significant greater percentage of patients with renal complications ( p = 0.012) than patients with normal strain (group 1). There was a significant relationship among mortality and GLS and E/e′ ( P value equal 0.014, < 0.001 respectively) in group C (high cardiac preload). Regarding the overall survival of studied patients ; however, the survival rate decreased with GLS >-8 (more positive) but the mean of overall survival was insignificantly different among the studied cases had GLS ≤ -8 and those with GLS >-8 due to relatively small number of patients. Conclusions Septic cases who have a high cardiac preload are more likely to have tachycardia, which is related to impaired left ventricular strain, a sensitive indication of cardiomyopathy. The current research illustrates a significant difference among study groups regarding in-hospital death, 28-days mortality and renal complications. High pre-load state (Group C ; E/e′ >14) had significantly higher in-hospital mortality, 28-days mortality and renal complications. A significant relationship has been found between mortality and GLS and E/e′ ( P value = 0.014, < 0.001 respectively) in group C (high cardiac preload). Regarding the overall survival of studied patients; however, the survival rate decreased with GLS >-8 (more positive) but the mean of overall survival was insignificantly different among the studied cases had GLS ≤ -8 and those with GLS >-8 because of relatively small number of cases. GLS might be a beneficial tool in expectation of death in septic cases had high preload and could be routinely performed while doing echocardiography.