‘Myocardial Depression’ or’ septic Cardiomyopathy’? In: Vincent J, editor. Intensive Care Medicine. New York: Springer; 2009. pp. 183-94. [DOI: 10.1007/978-0-387-92278-2_18]

Melatonin improved rat cardiac mitochondria and survival rate in septic heart injury

The pathogenesis of septic myocardial depression is complicated. Mitochondrial dysfunction has been suggested to be one of the main reasons for the reduced cardiac function. As melatonin is an antioxidant with the potential to scavenge radicals in mitochondria, we therefore employed a sepsis model, that is, cecal ligation and double puncture (CLP) in rats, to study the melatonin effects on: (i), myocardial mitochondrial function; (ii), heart systolic function; and (iii), prognosis of septic rats. We demonstrate that melatonin treatment (30 mg/kg, 3, 6, 12, 18, 24 hr after CLP) (i) improved myocardial cytochrome c oxidase (CcOX) activity and blood lactate level, (ii) attenuated heart dysfunction with a higher left ventricular ejection fraction (EF), and (iii) promoted 48-h survival of the rats compared to CLP animals with no melatonin treatment. In conclusion, our results show that rat myocardial mitochondrial CcOX activity was depressed during severe sepsis accompanied by myocardial depression characterized by the decline of EF. In septic rats, melatonin increased the CcOX activity, improved heart systolic function, and lowered mortality rate. The clinical use of melatonin in septic myocardial depression should be tested in the future.

[ECAIS study: inadvertent cardiovascular adverse events in sepsis]

OBJECTIVE

To describe the incidence of cardiovascular adverse events in patients with sepsis in its various stages.

DESIGN

A longitudinal, descriptive, observational study was carried out.

SETTING

Intensive care units of two university hospitals in Bogotá (Colombia).

PATIENTS

A number of patients consecutively admitted to the adult ICU with a diagnosis of sepsis, and no evidence of previous ischemic myocardial injury.

INTERVENTIONS

Forty-eight hours of electrocardiographic record using Holter technology.

MAIN VARIABLES

Ischemia, cardiac arrhythmia, heart rate variability.

RESULTS

A total of 100 patients were analyzed, 62% being staged as presenting septic shock. Three percent suffered ischemic events detected by Holter and unnoticed through conventional monitoring. Forty-six percent suffered an arrhythmic event detected by Holter, compared with only 6% as detected by conventional monitoring. Mortality was 40%. All patients showed loss of heart rate variability.

CONCLUSION

In this study patients with sepsis showed a low incidence of cardiovascular ischemic events. In contrast, arrhythmic events showed a high incidence. Conventional monitoring failed to detect any of the ischemic events and most arrhythmic events. In this study, cardiovascular events generated by adrenergic discharge had no impact upon mortality.