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

Early echocardiographic assessment of cardiac function may be prognostically informative in unresuscitated patients with sepsis: A prospective observational study.

PurposeThe goal of this study was to explore the association cardiac function at Emergency Department (ED) presentation prior to the initiation of resuscitation, and its change at 3-hours, with adverse outcomes in patients with sepsis.MethodsThis was a prospective observational study of patients presenting to an urban ED with suspected sepsis. Patients had a point-of-care echocardiogram performed prior to initiation of resuscitation and again 3 hours later. Left-ventricular (LV) parameters recorded included e', and E/e', and ejection fraction (EF); right-ventricular (RV) function was evaluated using tricuspid annular plane systolic excursion (TAPSE). Logistic and generalized linear regression were used to assess the association of echocardiographic parameters and ≥ 2-point increase in SOFA score at 24 hours (primary outcome) and 24-hours SOFA score and in-hospital mortality (secondary outcomes).ResultsFor ΔSOFA ≥ 2 and 24-hour SOFA score, declining LVEF was associated with better outcomes in patients with greater baseline SOFA scores, but worse outcomes in patients with lower baseline scores. A similar relationship was found for ΔTAPSE at 3 hours. Reduced LVEF at presentation was associated with increased mortality after adjusting for ED SOFA score (odds-ratio (OR) 0.76 (CI 0.60-0.96). No relationship between diastolic parameters and outcomes was found. IVF administration was similar across ΔLVEF/TAPSE sub-groups.ConclusionsOur results suggest that early change in LV and RV systolic function are independently prognostic of sepsis illness severity at 24-hours. Further study is needed to determine if this information can be used to guide treatment and improve outcomes

Isotope ratios of H, C, and O in CO2 and H2O of the Martian atmosphere

Stable isotope ratios of H, C, and O are powerful indicators of a wide variety of planetary geophysical processes, and for Mars they reveal the record of loss of its atmosphere and subsequent interactions with its surface such as carbonate formation. We report in situ measurements of the isotopic ratios of D/H and O-18/O-16 in water and C-13/C-12, O-18/O-16, O-17/O-16, and (CO)-C-13-O-18/(CO)-C-12-O-16 in carbon dioxide, made in the martian atmosphere at Gale Crater from the Curiosity rover using the Sample Analysis at Mars (SAM)'s tunable laser spectrometer (TLS). Comparison between our measurements in the modern atmosphere and those of martian meteorites such as ALH 84001 implies that the martian reservoirs of CO2 and H2O were largely established similar to 4 billion years ago, but that atmospheric loss or surface interaction may be still ongoing