Myocardial infarction, myocardial ischemia, ventricular dysrhythmias, and sudden cardiac death occur most frequently in the morning, especially in the first few hours after awakening. Among individual patients, however, this pattern may vary widely. Up to 80% of individuals who suffer sudden cardiac death have coronary heart disease; the epidemiology of sudden cardiac death to a great extent parallels that of coronary heart disease. This review describes circadian patterns in cardiovascular disease processes and analyses the findings of recent studies by searched, from PubMed, ISI Web of Science, Google Scholar and Scopus databases in a time period between late 1970s through July 2013. The circadian pattern of numerous cardiovascular events (myocardial infarction, sudden cardiac death, stroke) reveals a peak in the early hours of the morning, which occurs in more than 20% of patients with arterial hypertension, and can be regularly detected in combined 24-h-ABPM/EKG examinations. The awareness of an increased incidence of myocardial infarction and sudden cardiac death in the early morning hours, shortly after waking, has stimulated an interest in the relationship of these events and the occurrence of both silent and symptomatic myocardial ischaemia. A number of studies have been reported that examine both the physiological triggers and the underlying causes of these events. Beta-adrenergic blockers have been shown to abolish the early morning peak of myocardial infarction and blunt the morning peak in sudden cardiac death. Newer calcium antagonists, such as amlodipine, have been demonstrated to control angina throughout a 24-hour period. Aspirin is effective in preventing morning infarction. Approaching the pathophysiology of circadian time-dependent sudden cardiac death has implication for future prevention and treatment.
Fish and n−3 fatty acids for the prevention of fatal coronary heart disease and sudden cardiac death
