Pathophysiology, echocardiographic evaluation, biomarker findings, and prognostic implications of septic cardiomyopathy: a review of the literature

Abstract

Background: Sepsis is a common condition encountered by emergency and critical care physicians, with significant costs, both economic and human. Myocardial dysfunction in sepsis is a well-recognized but poorly understood phenomenon. There is an extensive body of literature on this subject, yet results are conflicting and no objective definition of septic cardiomyopathy exists, representing a critical knowledge gap.

Objectives: In this article, we review the pathophysiology of septic cardiomyopathy, covering the effects of key inflammatory mediators on both the heart and the peripheral vasculature, highlighting the interconnectedness of these two systems. We focus on the extant literature on echocardiographic and laboratory assessment of the heart in sepsis, highlighting gaps therein and suggesting avenues for future research. Implications for treatment are briefly discussed.

Conclusions: As a result of conflicting data, echocardiographic measures of left ventricular (systolic or diastolic) or right ventricular function cannot currently provide reliable prognostic information in patients with sepsis. Natriuretic peptides and cardiac troponins are of similarly unclear utility. Heterogeneous classification of illness, treatment variability, and lack of formal diagnostic criteria for septic cardiomyopathy contribute to the conflicting results. Development of formal diagnostic criteria, and use thereof in future studies, may help elucidate the link between cardiac performance and outcomes in patients with sepsis.

Keywords: B-type natriuretic peptide; Echocardiography; Sepsis; Troponin; Ultrasound.

Fig. 1

Pathophysiology of septic myocardial dysfunction. IL interleukin, iNOS induced nitric oxide synthase, PMN polymorphonuclear cell, TNF tumor necrosis factor

Fig. 2

a Speckle-tracking analysis of a patient with normal systolic left ventricular (LV) function. 2D image showing speckles within the LV being tracked by the ultrasound Machine Software (A). Graphical representation of movement of speckles throughout the cardiac cycle (x-axis, longitudinal strain; y-axis, time in msec), with each line representing a different segment of the LV; large negative values represent movement of speckles towards one another during contraction representing normal function (B). Bullseye map showing global longitudinal strain values throughout the LV (C). b Speckle-tracking analysis of a patient with severely reduced left ventricular (LV) systolic function. A 2D image showing speckles within the LV being tracked by the ultrasound machine software (A). Graphical representation of movement of speckles throughout the cardiac cycle (x-axis, longitudinal strain; y-axis, time in msec) with each line representing a different segment of the LV; note smaller negative values with variable time to peak strain representing reduced LV function with mechanical dyssynchrony (B). Bullseye map showing global longitudinal strain values throughout the LV; blue zones represent areas of the LV where there is lengthening of the segments during systole rather than shortening (C)