A recent study published in the journal Nature highlights the critical role of sleep in recovering from a heart attack.
The findings reveal that the heart communicates with the brain through the immune system, prompting the body to seek more sleep as a way to reduce inflammation and promote healing.
Researchers from the Icahn School of Medicine at Mount Sinai in the United States conducted experiments on mice, inducing heart attacks in some and using implanted wireless electroencephalography (EEG) devices to monitor brain activity. The results showed that after a heart attack, the mice significantly increased their sleep duration, particularly in deep, slow-wave sleep, which tripled in length and lasted for a week.
NEW STUDY: Impact of Sleep Disruption on Cardiac Healing after Heart Attack
Video by Peter Munk Cardiac Centre
Further investigation revealed that monocytes, a type of immune cell, were recruited to the brain after a heart attack. These cells activated neurons in the thalamus region of the brain using a protein called tumor necrosis factor. This activation occurred within hours of the heart attack and led to increased sleep in the affected mice. In contrast, the control group of mice did not exhibit these changes.
The study also found that during sleep, the brain sends signals to the heart via the nervous system, reducing stress on the heart, promoting recovery, and decreasing post-heart attack inflammation. However, when researchers disrupted the sleep of some mice after a heart attack, these animals exhibited heightened cardiac stress responses and increased inflammation, leading to slower recovery compared to those whose sleep remained uninterrupted.
To validate these findings in humans, the research team conducted several clinical studies. They examined the brains of patients within one to two days of a heart attack and found elevated levels of monocytes compared to individuals without heart conditions, mirroring the results seen in animal experiments.
The team also analyzed the sleep patterns of over 80 heart attack patients during the four weeks following the event. Patients with poor sleep during this period showed worse outcomes, with slower or minimal improvement in heart function. In contrast, those who slept well experienced significant improvements in cardiac function.
These findings underscore the importance of sufficient sleep following a heart attack. Researchers recommend that adequate sleep should be prioritized as a key aspect of clinical management and care for heart attack patients, particularly in intensive care units, where sleep is often disrupted. Ensuring restful sleep not only supports the recovery process but may also improve long-term outcomes for heart attack survivors.
