• Changes in circulating inflammatory cytokines (Interleukin [IL]-1B, IL-6, IL-10, and Tumor Necrosis Alpha [TNF-α]) and pro-coagulant mediators (soluble P-selectin and CD40 ligand). [ Time Frame: 2 days ] [ Designated as safety issue: No ]
  

• Changes in objective and subjective measures of sleep [ Time Frame: 4 days ] [ Designated as safety issue: No ]
  

Abnormalities of sleep are common in hospitalized patients, but the mechanisms and consequences are not well understood. In many of these patients, sleep is very disrupted, occurs during the daytime, and circadian rhythm is diminished or lost. Hospitalized patients experience more frequent arousals and awakenings than is normal and show decreases in rapid eye movement and slow wave sleep. The degree of sleep fragmentation is at least equivalent to that seen in patients with obstructive sleep apnea. About 20% of arousals and awakenings are related to noise, 10% are related to health care personnel and care-related activities, and the cause for the remainder is not known, although severity of underlying disease is likely an important factor.

In studies of sleep following acute myocardial infarction, marked disturbances have been found in patients, whether in the ICU and on the wards. These disturbances include long periods of wakefulness; poor sleep efficiency, and disruption of REM sleep. The fact that there is also a loss in circadian rhythm in these patients may indicate a widespread disruption of bodily homeostasis which, in turn, may be related to the infarct itself, to a more generalized physiological response to stress or to other factors. Sleep disruption can induce sympathetic activation and elevation of blood pressure, which may contribute to patient morbidity.

It has been shown that there is an increased level of some inflammatory and coagulation factors in the recovery period following an acute myocardial infarction (MI). Post MI patients have higher levels of TNF-α, IL-6 and tissue plasminogen activator as well as lower levels of antithrombin III and protein C.

The aim of this study is to determine whether the sleep-aid Eszopiclone can improve sleep, decrease inflammation, and decrease pro-coagulation factors in patients who have recently suffered myocardial infarction when compared with a control group without sleep aids. Eszopiclone is a benzodiazepine receptor agonist which improves sleep quality by reducing the time to sleep onset and reduces wakefulness during the sleep period. Unlike benzodiazepines, it does not affect the deeper stage 3 and 4 sleep. The result is that it provides a more nearly normal night sleep than other sleep aids. It is hoped that improved sleep patterns will result in more rapid normalization of inflammatory and coagulation factors and perhaps more rapid recovery.