Left Ventricular Longitudinal Systolic Function in Septic Shock Patients with Normal Ejection Fraction: A Case-control Study

BACKGROUND Septic cardiomyopathy is a common finding in septic shock patients. The accepted definition of septic cardiomyopathy is often based on the left ventricular ejection fraction (LVEF). The aim of this study was to determine whether the left ventricular longitudinal systolic function was more sensitive than the LVEF in heart function appraisal of septic shock patients. METHODS This was a case-control study conducted at a 40-bed Intensive Care Unit (ICU) of Peking Union Medical College Hospital. Septic shock patients admitted to the ICU were consecutively enrolled in the study group from March 1, 2016 to September 1, 2016. The control group was selected from nonsepsis patients who were admitted to the ICU and were comparable to the study group. Transthoracic echocardiography was performed to obtain the LVEF measurement, mitral annular plane systolic excursion (MAPSE), tissue Doppler velocity measurement of mitral annulus (Sa), and tricuspid annular plane systolic excursion. RESULTS The study group consisted of 45 septic shock patients. Another 45 nonsepsis patients were selected as the control group. There was no difference in the LVEF between the two groups (64.6% vs. 67.2%, t= -1.426, P= 0.161). MAPSE in the study group was much lower than in the control group (1.2 cm vs. 1.5 cm, t= -4.945, P< 0.001). Sa in the study group was also lower than in the control group (10.2 cm/s vs. 11.8 cm/s, t = -2.796, P= 0.014). CONCLUSIONS Compared to the LVEF, longitudinal systolic function might be more sensitive in the detection of cardiac depression in septic shock patients. In the heart function appraisal of septic shock patients with a normal ejection fraction, more attention should be given to longitudinal function parameters such as MAPSE and Sa.