Effects of Zolpidem CR® in Sleep and Heart Recovery in Cardiac Intensive Care Unit Patients

A double blind, randomized, placebo-controlled study will be conducted in cardiac ICU patients who had been diagnosed with acute coronary syndrome, using a sleep promoting drug (zolpidem controlled release). The study hypothesis is that sleeping better can improve the heart recovery in patients with a diagnosis of acute coronary syndrome.

The environment of an Intensive Care Unit (ICU) is notoriously inhospitable to patients who experience a period of sleep deprivation (SD). Recent research has shown that SD, even in the short-term, may be related to echo and electrocardiographic changes that may potentially be predictors of cardiac arrhythmias. The objective is to evaluate the effects of early treatment with zolpidem controlled release (CR®) compared to a placebo on clinical and polysomnographic parameters for patients in a cardiac ICU who had recently been diagnosed with acute coronary syndrome. A double blind, randomized, placebo-controlled study will be conducted in cardiac ICU patients who had been diagnosed with acute coronary syndrome. The patients in group A will receive placebo and patients in group B will receive zolpidem CR® 12.5 mg from the first night of hospitalization until their discharge. Patients will undergo overnight full polysomnography on the first night in the ICU and will complete a sleep diary with a visual analogue scale to evaluate sleep quality in the morning after the first 3 nights of hospitalization. The results of the routine ICU laboratory tests including the serum levels of cardiac enzymes [troponin T and creatine kinase MB (CK-MB)] will be collected preceding the first dose of the drug/placebo, and then daily thereafter.

Patients receive zolpidem CR 12.5mg at bedtime from the first night on the Cardiac Intensive Care Unit until their discharge from the hospital

Patients receive placebo at bedtime from the first night on the Cardiac Intensive Care Unit until their discharge from the hospital

Patients will be given zolpidem CR 12.5mg each night for, at least, 3 consecutive nights, including the first night on the Cardiac ICU, when the undergo a full-night polysomnography

Patients will receive placebo pills at night, according to their usual sleep time, from the first night on the Cardiac ICU, until their hospital discharge

The serum creatine-kinase MB is measured previously of the intervention and daily for 3 consecutive days

After receiving the drug or placebo at night, the next morning the patients fill in the sleep quality visual analogue scale

Inclusion Criteria: Patients from 18 to 75 years of age Diagnosis of acute coronary syndrome Capable of swallowing pills Capable of filling in the questionaires Exclusion Criteria: Class IV heart failure according to the New York heart association functional class, Patients in a coma Patients receiving mechanical ventilation Patients who regularly use benzodiazepines or other medications for inducing sleep