Syncope-a question and an answer

Laura one of my readers had an interesting query. I am publishing her question here as I feel, it may help others who are experiencing the same problem. My answer to her query follows.

Laura Frankiewicz on October 6, 2008 said: Edit Link

Dear Dr. Sethi,
I seem to have been having vasovagul syncope for at least 6 years or so. I feel that they started when I began menopause (I am now 56 and haven’t had a period for over a year. I almost always have a prodomal senation and have never actually passed out. My last episode happened yesterday at the theatre. Let me begin by saying that I take altace for high blood pressure and hychlorathyizide as a diuretic so I may have been dehydrated but I had just drunk quite a bit of water. What I am wondering instead if the lightling could have affected me. The lobby of the theatre has very dim and strange lighting that I find very disturbing. We got there early so I sat under the lighting for almost an hour. Then when we were seated, the area was fairly small and cramped. I had my legs crossed but fairly soon broke out into a sweat and began getting intestinal cramps. The feeling that I had to move my bowels became extreme and I got up to go to the bathroom but by then I was pretty woozy and weak. I managed to get to the usher but had to lie down. After a few minutes they helped me up and I laid down with my Legs elevated. I stayed in this position for only a few minutes while they got my information and I convinced the theatre staff not to call the paramedics. They helped me to the bathroom where upon I was able to evacuate and felt much better. I also drank some more water. I was ultimately re-seated on the ground floor and was able to finish watching the performance. But I have had close calls in this same theatre. It is close and crowded but I always wear sleeveless clothes so as not to overheat. I am not a nervois or panicky person. Most of my syncope episodes have been in warm places; after eating soup, having a pedicure with my feet in warm water. I can always avert the actual fainting. I have never lost consciousness. I guess what I am wondering is if lighting can have a neurological impact that would cause vasovagul syncope. I have had a number of stress tests, the last being last year, a nuclear echocardiagram; all clear. I do not think this is related to my heart but now I am wondering if I should consult with a neurologist. I would appreciate your advice. Also, very often the prodomal sensation includes a strong urge to move my bowels. Has this sensation been reported by others with syncope?
Thank you,
Laura Frankiewicz

  • 4 braindiseases on October 7, 2008 said: Edit Link

    Dear Laura,
    thank you for writing in. It does seem you have being having what we refer to as pre-syncopal episodes (meaning a syncope like episode but not quite syncope, since you do not pass out and lose consciousness). Moreover your history suggests you feel these episodes coming-feeling dizzy, light headed, about to faint type feeling and breaking out into a sweat.
    Various factors might precipitate a syncopal episode. In the case of vasovagal syncope these might include strong emotional experiences like for example seeing blood for the first time. Strong visceral sensations may also bring on an episode. Micturition syncope has been reported in elderly men (they pass out when they get up at night to void urine). Patients have been reported to pass out as they sit on the toilet seat and exert pressure.
    It is likely that something along the same mechanism might be operative in your case. Dehydration and been in a closed crammped theatre may have further contributed to the problem. Whenever a patient presents to the hospital with syncope, we have to determine whether the cause is the heart or the brain (cardiogenic versus neurogenic/ vasovagal). Also at times it is hard to differentiate seizures from syncope.
    My advise to you would be to consult a neurologist (ask your PMD to refer you to one). I am sure they would be able to get to the bottom of your problem. Feel free to write in again.
    Personal Regards,
    Nitin Sethi, MD

  • Syncope: making sense of its various causes

    Recently I was consulted on two patients who presented to the hospital after a syncopal episode. As syncope is relatively common, I thought that is what I should discuss in my next post.

    So what is syncope? Well simply put a syncopal episode is nothing other than a fainting episode. It is characterized by momentary/ temporary loss of consciousness and posture. Patients may refer to it as I “fainted” or “passed out”.  Whenever a patient presents to the hospital after a syncopal episode we take pains to find out what led to the syncope.

    So what are the different causes of syncope?  Syncope can come either from the heart or from the brain. Let me explain this further. If for some reason the heart suddenly malfunctions and stops pumping blood to the brain, you will pass out (lose consciousness). This is referred to as cardiogenic syncope. Among the various causes of cardiogenic syncope are included disorders of cardiac rhythm such as atrial and ventricular arrhythmias. Heart blocks and of course an acute myocardical infarction (heart attack) may present as a syncopal episode with the patient collapsing and passing out.

    Syncope though can also come from the brain and this is referred to as neurogenic syncope or at times as neurocardiogenic syncope. This neurally mediated syncope is also at times referred to as vasovagal or vasodepressor syncope. Let me explain what vasovagal syncope is with a classical example. Lets assume you are walking on the street. A car hits a cyclist right in front of you. You rush to help the poor man. As you come near, you see him bleeding profusely, his skull cracked open. You go pale, the blood drains from your face and you pass out. There you just had a vasovagal syncopal episode. Why you may ask did you pass out?

    Vasovagal syncopal episodes classically occur in the upright position meaning either you are sitting upright or standing (they usually do not occur when you are reclining). The episode is usually preceded by an unpleasant or painful episode such as the sight of blood, a medical procedure, an intense emotionally disturbing argument or news (sudden extreme emotions), standing in the hot sun or a hot shower for a long time especially if you are hungry and dehydrated at the same time.

    Other less common triggers may include a bout of violent coughing (cough syncope), urination (micturition syncope) and abdominal straining as during defecation.

    Usually prior to the onset of the syncope (prior to passing out), patients feel dizzy and light headed. They may complain of blurring of vision and feel as if they are about to faint. If at this stage the person sits down, they usually do not pass out or lose consciousness. This is referred to as pre-syncope (A syncopal episode was about to occur but since the patient sat down it was aborted midway).

    During a vasovagal synope episode there is transient loss of the baroreflexes (this is the autonomic nervous system which helps to maintain our blood pressure). Pooling of blood occurs in the dependent calf muscles and there is lack of blood flow to the brain resulting in the patient passing out. Hence one of the simple things to do when a person has a vasovagal syncopal episode is to make them lie down flat on the ground on their back and to lift the legs above the plane of the heart. As the blood rushes back to the brain, the person quickly comes around and may look a little dazed wondering what happened.

    As seizures too are associated with loss of consciousness, one always has to differentiate whether a patient had a seizure Vs a syncopal episode. As you can imagine it is important to make this differentiation as the two conditions are treated in very different ways. So how does one differentiate a seizure from a syncopal episode?

    A seizure can occur with the patient in any position: sitting, standing or lying down. Syncope usually occurs in the erect posture.

    Seizures are usually not preceded by the prodrome seen in syncope. Patients before they pass out in a syncopal episode complain of feeling light-headed, dizzy, room spinning and blurring of vision. Seizure patients on the other hand may give history of their aura prior to the seizure. Common auras include smelling of burning rubber, metallic taste in their mouth or a funny rising sensation in their tummy.

    Patients who have a seizure and fall usually hit and hurt themselves. They fall hard and may come to the hospital with craniofacial injuries like broken teeth. Syncopal patients on the other hand do not fall hard, they rather ease themselves to the ground.

    Some but not all seizures are associated with tongue biting and loss of bladder and bowel control (patient may pee on themselves and wet their pants). Most syncopal episodes are not associated with tongue biting or loss of bladder control.

    Patients after a seizure are usually confused and disoriented, they may fall asleep. We call this a post-ictal state. Syncopal patients as they come out of their syncope are not confused. They know where their are and may be embrassed by the fact they fainted.

    In my next post I shall discuss the diagnostic work-up and management of syncope.

    Nitin Sethi, MD