Disruption of Circadian Rhythms and Sleep in Critical Illness: Potential Implications for Angiogenesis After Myocardial Infarction. A Review

Angiogenesis plays an important role in the treatment of acute myocardial infarction (MI). Formation of micro-vessels has the potential to prevent apoptosis of the ischemic myocardium and to improve cardiac function after MI. Delivery of growth factors or administration of stem/progenitor cells (mainly from bone marrow) are the dominant therapies to induce angiogenesis after MI. Nevertheless, clinical trials have shown that delivery of a single growth factor or single type of cell does not provide sufficient angiogenesis to promote cardiac repair. Circadian rhythms control many physiological and pathological processes in mammals. Many studies show a close relationship between circadian rhythms and MI. Disruption of the circadian rhythms in humans leads to increased incidence of MI. The onset and infarct area of MI are markedly elevated at certain time points. Determining the mechanisms of angiogenesis and vessel maturation in the ischemic heart under the control of circadian rhythms could help in the development of novel and angiogenesis- targeted therapeutics for the treatment of MI.