Thanks for using the forum. I am happy to address your questions, and my answer will be based on the information you provided here. Please make sure you recognize that this forum is for educational purposes only, and it does not substitute for a formal office visit with your doctor.
Without the ability to obtain a history from you and examine you, I cannot comment on a formal diagnosis or treatment plan for your symptoms. However, I will try to provide you with some information regarding this matter.
Your boyfriend's clinical history is suggestive of syncope (passing out). There are many different reasons for syncope.
Differentials include, Transient Ischemic attacks (TIA), which is a warning sign of a stroke, a stroke itself, or cardiac arrhythmias. Two major groups of arrhythmias are bradycardia and tachycardia. Bradycardia( is a slower heart rate than the normal, usually less than 60beats per minute. Sometimes it can be normal or related to a side effect of medications. The reason why these can cause syncope/nearsyncope is because the heart is not pumping enough blood to the brain. Fast heart rates, tachycardias, can also cause syncope/nearsyncope because the heart is unable to fill adequately with blood to pump to the brain. Orthostatic hypotension (blood vessels cannot constrict when standing up, therefore causing pooling of blood in the legs-->not enough blood to the brain).
Another cause can be a seizure, in which you lose all muscle tone. This is usually due to too much electrical activity in a certain area in the brain.
A thorough examination is required in order to determine the cause. An initial work-up should include:
1) Routine blood work with cardiac enzymes.
2) ECG (electrocardiogram) to look at the heart’s electrical activity to see if there is brady/tachycardia. Also, ECGs are helpful in diagnosing heart attacks or ischemia (lack of blood)
3) Cat Scan of the Head to rule out any bleeds in the brain. This can be followed up by an MRI and MRA of the Brain to look at the blood vessels and the back of the brain to see if there were any strokes or other causes to faint.
4) Cardiac Echocardiogram—an ultrasound of the heart to look at its function
5) Holter monitor: Sometimes an ECG will not catch pauses of the heart or transient episodes of arrhythmias, therefore this is a monitor you wear (looks like a Walkman) for 2 days and it monitors your heart continuously.
6) EEG (Electroencephalogram)—to look at the brain’s electrical activity. This may not pick up a seizure, however may tell if there is a reason that may be prone to having seizures.
7) Tilt table testing—to see if different positions cause his body to not be able to adapt and cause not enough blood flow to the brain. This test would check his heartrate and blood pressure.
These are just some of the basic tests that should be done.
Hope this information was helpful. Best of luck.
Has cataplexy (a hallmark symptom of narcolepsy and rarely seen outside of it) been ruled out? It would fit the sudden onset as well as remaining conscious the entire time.
You can learn more about cataplexy by searching for cataplexy on wikipedia (sorry I can only get the mobile URL on my cell phone right now or I'd give you a link. There is also info on the narcolepsy network site that you should be able to find if you google their name and cataplexy.
Feel free to message me with questions on ruling that out (I have it).