Cardiac Stress in Septic Shock - Biomarkers, Echocardiography and Outcome
Cardiac Stress in Septic Shock - Biomarkers, Echocardiography and Outcome
Septic shock is a major cause of death in intensive care. Septic shock is often dominated by
 profound changes in organ functions, of which cardiac failure is one of the most severe. In
 septic shock, biological markers of cardiac stress are often elevated. It is not known to
 what extent this indicates structural damage to the heart, or in what way they correlate to
 echocardiographic signs of heart failure.

 Here, cardiac failure in ICU patients with septic shock is studied, using biological markers
 of cardiac stress, inflammatory parameters and echocardiography.

 Investigators hypothesize that biomarkers of cardiac stress correlate with echocardiographic
 signs of heart failure, and that they can predict an increased risk of death.
Sepsis and septic shock are major health concerns worldwide. Sepsis is the consequence of
 inflammatory processes and humoral and cellular reactions to severe infection. Its clinical
 presentation is variable, with a continuum from a systemic response to infection to fulminant
 disease refractory to resuscitation and with multiple organ failure. Septic shock is the most
 severe form of sepsis and the leading cause of death in intensive care patients with a high
 mortality despite modern resuscitation and treatment.

 Septic shock is dominated clinically by circulatory changes presenting with profound
 vasodilatation and hypotension. Cardiac output values are often seemingly normal, or even
 enhanced, when compared with the physiological range. However, relative to the
 vasodilatation, cardiac output is often not adequately enhanced. Thus, the degree of
 myocardial depression in sepsis is often underestimated by the clinician, albeit a factor
 that markedly increases mortality.

 Septic cardiomyopathy typically engages both ventricles globally, and involves diminished
 cardiac response to volume and circulating catecholamines. It is not primarily hypoxic, but
 rather has a multifactorial origin. In survivors, it is typically reversible, but long-term
 consequences are not known.

 Cardiac biomarkers, i.e. troponins and natriuretic peptides, are all associated with worse
 outcome in septic shock. Cardiac troponins are frequently elevated and correlate to the
 duration of hypotension and the intensity of vasopressor support. Elevated natriuretic
 peptides predict adverse outcome, and values are often markedly elevated even in seemingly
 normal echocardiographic findings. It is not clear whether this indicates structural
 myocardial damage, or rather demonstrate a global septic membrane leakage. Thus, with the
 complexity of sepsis, combinations of cardiac biomarkers and markers of global inflammation
 may provide a more robust tool for stratification and prognostication and for evaluation of
 septic organ dysfunction. In clinical cardiology, combinations of biomarkers of myocardial
 stress are used for stratification and prognostication of myocardial failure, but the role of
 such multimarker panels in septic cardiomyopathy has not been studied.

 Echocardiography is used clinically, and has been the focus of several studies, to
 characterize septic cardiomyopathy. Echocardiographic signs of systolic dysfunction has been
 the main focus of previous investigations, and the systolic component is the focus of modern
 guidelines of clinical management in septic cardiomyopathy. The role of diastolic dysfunction
 is gaining interest, with data suggesting higher mortality in patients with diastolic
 dysfunction than in those with systolic dysfunction. To date, the correlation of
 echocardiographic signs of systolic or diastolic dysfunction myocardial stress biomarker
 panels, and the dynamics of any correlation, has not been studied.

 The hypothesis of this study is that biological markers of cardiac stress correlate with
 echocardiographic signs of cardiac failure, that they can predict outcome, and that they
 correlate to conventional methods of outcome prediction.
Inclusion Criteria:

 -  Adult patients admitted to ICU for severe sepsis or septic shock

 Exclusion Criteria:

 -  Expected ICU stay <24hrs

 -  Patients in which mental inabilities or language barriers impair the possibility of
 informed consent.