Evaluating the Association Between the Three Different Ejection Fraction Measurement Techniques and Left Ventricle Global Strain

Levosimendan versus dobutamine for sepsis-induced cardiac dysfunction: a systematic review and meta-analysis

Levosimendan and dobutamine are extensively used to treat sepsis-associated cardiovascular failure in ICU. Nevertheless, the role and mechanism of levosimendan in patients with sepsis-induced cardiomyopathy remains unclear. Moreover, previous studies on whether levosimendan is superior to dobutamine are still controversial. More importantly, these studies did not take changes (before-after comparison to the baseline) in quantitative parameters such as ejection fraction into account with the baseline level. Here, we aimed to determine the pros and cons of the two medicines by assessing the changes in cardiac function and blood lactate, mortality, with the standardized mean difference used as a summary statistic. Relevant studies were obtained by a thorough and disciplined literature search in several notable academic databases, including Google Scholar, PubMed, Cochrane Library and Embase until November 2020. Outcomes included changes in cardiac function, lactic acid, mortality and length of hospital stay. A total of 6 randomized controlled trials were included in this study, including 192 patients. Compared with dobutamine, patients treated with levosimendan had a greater improvement of cardiac index (ΔCI) (random effects, SMD = 0.90 [0.20,1.60]; I2 = 76%, P < 0.01) and left ventricular stroke work index (ΔLVSWI) (random effects, SMD = 1.56 [0.90,2.21]; I2 = 65%, P = 0.04), a significant decrease of blood lactate (Δblood lactate) (random effects, MD =  - 0.79 [- 1.33, - 0.25]; I2 = 68%, P < 0.01) at 24-h after drug intervention, respectively. There was no significant difference between levosimendan and dobutamine on all-cause mortality in ICU (fixed effect, OR = 0.72 [0.39,1.33]; I2 = 0%, P = 0.99). We combine effect sizes related to different measurement parameters to evaluate cardiac function, which implied that septic patients with myocardial dysfunction might have a better improvement of cardiac function by levosimendan than dobutamine (random effects, SMD = 1.05 [0.69,1.41]; I2 = 67%, P < 0.01). This study suggested a significant improvement of CI, LVSWI, and decrease of blood lactate in septic patients with myocardial dysfunction in ICU after 24-h administration of levosimendan than dobutamine. However, the administration of levosimendan has neither an impact on mortality nor LVEF. Septic patients with myocardial dysfunction may partly benefit from levosimendan than dobutamine, mainly embodied in cardiac function improvement.

Association Between Echocardiographic Non-invasive Myocardial Work Indices and Myocardial Fibrosis in Patients With Dilated Cardiomyopathy

Objectives: To analyze the association between global myocardial work indices evaluated by non-invasive left ventricular (LV) pressure-strain loop (PSL) and LV myocardial fibrosis in patients with dilated cardiomyopathy (DCM).

Methods: A total of 57 patients with DCM were included in this prospective study. Global work index (GWI), global constructive work (GCW), global wasted work (GWW), global work efficiency (GWE) and global longitudinal strain (GLS) were measured using LVPSL. LV volumes and LV ejection fraction (LVEF) were evaluated using cardiac magnetic resonance imaging (CMRI), LV myocardial fibrosis was estimated at CMRI by qualitative assessment of late gadolinium enhancement (LGE). According to the CMRI, the studied population was divided into two groups, namely: patients without LGE (LGE-) and patients with LGE (LGE+).

Results: The LGE+ group presented with increased age, LV end systolic volume (LVESV) index and reduced GWI, GCW, GWE, GLS, CMRI-derived LVEF (LVEF_CMRI), the differences between the two groups were statistically significant (P < 0.05). After correcting for age and LVESV index, LVEF_CMRI, GLS, GWI, GCW, and GWE retained independent associations with LV myocardial fibrosis. According to receiver operating characteristics (ROC) analysis, LVEF_CMRI, and GCW showed larger AUC and higher accuracy, sensitivity, and specificity than GLS, the accuracy of predicting LV myocardial fibrosis ranged from high to low as: LVEF_CMRI, GCW, GWE, GWI, and GLS.

Conclusions: LVEF_CMRI, GWI, GCW, GWE, and GLS remained significant predictors of LV myocardial fibrosis. LVEF_CMRI, and GCW appeared to better predict LV myocardial fibrosis compared with GLS.

Left Ventricular Pressure-Strain Loop-Based Quantitative Examination of the Global and Regional Myocardial Work of Patients with Dilated Cardiomyopathy

The aim of our prospective pilot study was to explore the distribution characteristics of myocardial work (MW) of patients with dilated cardiomyopathy (DCM) and their clinical value in evaluation of therapeutic effects. Thirty patients with DCM were enrolled in the case group, and 30 healthy patients were randomly allocated to the control group. Global myocardial work (GMW) and regional myocardial work (RMW) of the control and case groups before and after therapy were evaluated by using left ventricular pressure-strain loops and then compared. We found significant differences in GMW and RMW between the control and case groups (p < 0.05). Compared with before therapy, the global work index and 6-min walking distance increased, but LV ejection fraction and global longitudinal strain did not significantly change after therapy. GMW was significantly correlated with LV ejection fraction and global longitudinal strain (p < 0.01). Bland-Altman plot analysis revealed that GMW values were consistent between and within the groups. The results suggest that LV MW values were diffusely impaired in patients with DCM and that the global work index may be used as an indicator in evaluation of therapeutic effects.