by Richard Ellin, MD, FACP
Question: I am an experienced rider, have ridden all my life and am 68 now. Nearly a year ago I had a crash on the second day of a 600 km Audax brevet, after riding 475 km. Because of head injuries I have no memory of the crash, but a witness said no other vehicle was involved. He just saw me sailing over the handlebars. [I unfortunately happened to land on my ear on a piece of concrete and my helmet didn’t save me from serious head injury (4 weeks in the hospital).] Ever since then I have been trying to figure out what might have happened. I would like to hear medical opinions about whether a cyclist can pass out without any warning symptoms or, if there are warning symptoms, what to be aware of. — Glen T.
Dr. Richard Ellin Responds: There are many possible causes of passing out, or what is known as syncope, in medical parlance. This can happen to anyone, at anytime.
Some of the more common causes include various heart conditions, anemia, and certain medications. Needless to say, if it happens when one is cycling or driving a car, it is potentially far more dangerous — for exactly the reasons you raised in your question.
Since you spent time in the hospital, Glen, I presume you had a thorough medical evaluation. However, sometimes even that will not reveal a specific cause. In cases such as yours, physicians at least try to make sure that you didn’t pass out due to a heart problem. If that was ruled out by your doctors, then whatever caused you to pass out is probably not serious, and less likely to recur.
However, if your medical team did not rule out a heart problem and could not pinpoint the cause, you should seek further testing.
A number of medical tests are typically done when investigating why a person may have passed out. If the initial evaluation, including various blood tests and an EKG, don’t reveal a cause, then further testing is often done.
Such additional tests typically include a Holter monitor (wearing a portable heart monitor for 24-48 hours), to try to identify intermittent abnormal heart rhythms, and an echocardiogram, to identify structural abnormalities of the heart.
Sometimes an EEG (recording of one’s brain electrical activity) is done as well, to make sure the person did not have a seizure. There are certain medications that could conceivably cause a passing out episode, although this is somewhat unusual.
Of course, make doubly sure you remain well-hydrated when cycling, especially on longer rides. If at any time you feel a little dizzy or lightheaded, get off the bike, and let your doctor know about it.
Richard Ellin, MD, FACP, is a board-certified specialist in Internal Medicine who practices in Alpharetta, Georgia. He received his medical degree and completed residency at Emory University, and has been in practice with Kaiser Permanente for more than 26 years. He is also an avid cyclist.
Jo says
I had similar experience two days ago, hence searched for information and found this. Fortunately I have less injuries. But it still confused how such could happen; I couldn’t recall anything, may about 10 seconds before, during and soon after the accident; I didn’t feel that my head hit the ground so har that my helmet was broken a piece. When I my consciousness was back I was already in someone’s house trying to help me. I will definitely have my heart check. Thanks.
Seetha says
I have been cycling for 10 years, 2 weeks ago while cycling back home, I blacked out, no recollection of me hitting the ground, luckily I was on a bike path. My fellow rider from a distance saw me laying on my back. He helped me sit up and assisted me to a close by bench, which I cannot recall. I rang my partner 10 time only remembering ringing once. My luck a retired Dr was there, I heard him saying, I was concussed and suffered amnesia to my partner, he rang the Ambulance. Ct scan and blood test done came out with flying colours. Dr at the hospital advices me to have Holter monitor and stress echocardiogram done. Will keep you posted.
Janice A. Buinis says
My husband was on his bike about three weeks ago. It was a hot and humid day! He has excercised in this weather before and never had an issue. He blacked out and fell! The next thing he remembers is waking up in the hospital. He had a cat scan, blood test, stress test, two echo cardiograms and an EP test. He is wearing a heart monitor for a month! They have found nothing so far that would have caused him to pass out. Doctors seem to think he may have been dehydrated,. I am anxious every time he drives or goes out alone! Anyone have any other ideas or suggestions?
Seetha says
On the third week of my accident I had Vertigo, nasty, I cannot tell you what I have been through. then a week after the Vertigo, I had dizziness, my neck is still giving me problems plus my lightheadedness is still there. I am seeing a Chiropractor. Physiotherapist did Epley manoeuvre very great full it fixed my vertigo, but I am still doing Epley manoeuvre twice a day by myself., due to the problems I have been having I am yet to do my Holter monitor test and stress test. MRI done recently still waiting for my results.