In this video from MedCram, Dr. Seheult discusses how he often as a pulmonologist and sleep specialist gets a lot of patients referred from cardiologists that have atrial fibrillation to look for obstructive sleep apnea. There is an atrial fibrillation and obstructive sleep apnea connection.
What is atrial fibrillation?
Atrial fibrillation occurs when the top part of the heart, the atria, are not contracting normally. They are fibrillating or in a layperson’s term wiggling and not effectively contracting. This is often caused when the atria gets stretched. The question is why are they being stretched out.
What happens in obstructive sleep apnea?
In obstructive sleep apnea, when you go to sleep, the muscles in the back of the throat relax and can cause an obstruction. You often hear this as a snore or snort. When the individual is trying to breathe and is unable to due to the obstruction for at least 10 seconds, no air is going into the lungs and hence no oxygenation is occurring. This leads to oxygen levels dropping. When this occurs, two things happen. In the brain, it alarms and causes the heart to increase in heart rate and causes a rise in blood pressure. The other thing that also happens is that the arteries going back to the heart in the lungs undergo what is called hypoxic pulmonary vasoconstriction when the oxygen levels are low. These arteries become constricted and when this happens there is a back pressure into the right ventricle. When the pressure in the right ventricle increases, the pressure in the right atrium also is increased. That increasing pressure can cause the right atrium to stretch. Similarly, when the brain stimulates the heart rate and blood pressure to go up, this also leads back to the heart. The pressures increase in the aorta and then with that increased pressure, there is increased pressure into the left ventricle and this leads back to increased pressure in the left atrium as well.
Why is atrial fibrillation a concern?
So when cardiologists find the patient in atrial fibrillation, the ideal goal is to try to get the patient to revert back to normal sinus rhythm. This can be done through medications, cardioversion or ablation. However, the goal is to keep the patient in sinus rhythm. If the patient has untreated obstructive sleep, this can cause the patient to go back into atrial fibrillation. So the patient is found to have atrial fibrillation, it is worth checking to make sure that they also do not have concurrent obstructive sleep apnea as well. MedCram has discussed different treatments for obstructive sleep apnea which include the use of CPAP, mandibular advancement device, hypoglossal nerve stimulator. You can get further information from our course on sleep apnea.
LINKS / REFERENCES:
Sleep Apnea Explained Clearly (MedCram) | https://www.medcram.com/courses/sleep…