DEADLY BITE: For people suffering from the rare condition, swallow syncope, eating a sandwich could cause cardiac arrest.
Image: iStockphoto.com/JoanVicent
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A little over a year ago, a 25-year-old woman visited University Hospital Birmingham in England complaining of frequent 10-second bouts of nausea and lightheadedness, which was sometimes so intense it caused her to pass out.
"She was very thin, she was pale, a very sensible young woman," says Una Martin, a clinical pharmacologist at the hospital assigned to the case shortly after the woman's first visit. She had no history of smoking, heavy drinking or psychiatric disorders. Strangely, her fainting episodes coincided with eating sandwiches and drinking fizzy beverages.
By the time Martin saw her, the woman had been bounced from one physician to the next and hospitalized twice, once in 2001 and once in 2007—but her condition remained a mystery.
"She felt she had been passed from doctor to doctor [and] was beginning to feel it was all in her head," Martin says. Some of the physicians she had visited thought she was suffering from petit mal seizures—brief epileptic brain episodes characterized by loss of consciousness but without the violent shaking associated with the larger grand mal seizures. Yet neurological tests showed no evidence of epilepsy.
Martin suspected there might be something wrong with the patient's heart, so she sent her patient home with an external loop electrocardiogram recorder, a device worn on the wrist or waist to monitor heart rhythm for extended periods of time. Whenever the young woman felt lightheaded, she would press a button on the device, causing it to record one to two minutes of heart activity. After monitoring her heart for a week, the woman returned the device to Martin who interpreted the results.
Her findings: during dizzy spells (following eating or drinking) the patient experienced complete atrioventricular block, a condition in which the electrical current traveling from the top two chambers of the heart (atria) to the bottom two chambers (ventricles) is disrupted. "I picked this up and referred her to the cardiologists," Martin says.
The cardiologists kept the young woman in the hospital where her heart rate and blood pressure were continuously monitored: "We offered her a sandwich. Atrioventricular block, lasting longer than two seconds, ensued; the patient felt lightheaded, as though she were about to faint," they reported in The Lancet. "We diagnosed swallow syncope."
Swallow syncope? ScientificAmerican.com asked Douglas Zipes, an Indiana University School of Medicine cardiologist and editor in chief of Heart Rhythm, to explain the bizarre condition.
What is swallow syncope?
It is when swallowing induces loss of consciousness. The swallowing triggers a vagal [nerve] reflex from the esophagus to the brain and back to the heart [that] is excessive in its reflex strength. The heart is very sensitive to that reflex response…[and this leads to] a slowing of the heart rate so as to create insufficient blood flow to the brain, causing someone to black out. No one knows why they have these very unusual reflexes.
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7 Comments
Add CommentI can't wait for this condition to appear on an episode of 'House'.
Reply | Report Abuse | Link to thisHouse would need to combine swallow syncope with the mercury story earlier!
Reply | Report Abuse | Link to thisSo that thing about Mama Cass choking on a ham sandwich...True!
Reply | Report Abuse | Link to thisNo kidding! I'd like to see what different diagnoses they come up with before House makes them feel silly for not realizing it's a swallow syncope!
Reply | Report Abuse | Link to thisAnd they said smoking causes heart attacks. LMAO!!! Anything apparently CAN!
Reply | Report Abuse | Link to thisI am surprised no one has mentioned the Bush pretzel incident:
Reply | Report Abuse | Link to thishttp://edition.cnn.com/2002/ALLPOLITICS/01/13/bush.fainting/
For the sake of possibly helping someone else, here is a brief story of my own experience with swallow syncope.
Reply | Report Abuse | Link to thisI have had the condition for about 20 years and it was never diagnosed until recently. Actually I diagnosed it myself in frustration that doctors did not recognize it. I had many eating situations ending up in syncope (fainting). A neurologist accurately felt it was a vaso vagal response. I had a barium swallow and all looked well. So, I just felt it was something I had to live with. Up until 10 years ago I fainted many times while eating scaring everyone around me. I got to the point where I could tell when it was going to happen and if I got some water to swallow quickly I could prevent it. Then on Dec. 17, 2011 I was home alone, reading in my husband's comfortable chair. I had a bit to eat while sitting there and did not have water handy. However, I did not get that feeling of being about to faint. I noticed something was not right, everything became very quiet, like the clock stopped ticking in the room. I felt my life force draining out through my feet and worried that my husband would come home and find me dead in his chair. I couldn't remember breathing so I took several big breaths and then tried to get out of the chair. I am a very strong woman, but I could not get up. Finally on the 3rd try I did get up but my legs were folded and barely working. By this time I was nauseated and, clinging to furniture I made my way into the kitchen where I vomited violently several times. I had no idea what was happening--a stroke, food poisoning? I was hungry for dinner that night and slept well. The next night I was awake all night figuring it out. In the morning I researched on the computer and figured out that I had experienced a total AV block. After seeing my family doctor I was referred to a cardiologist, who was not familar with swallow syncope (it is quite rare). She put me on a heart monitor. Within 3 days, while eating a sandwich my heart paused for 8 seconds. We figured that on 12/17/2011 my heart paused for 15-30 seconds with maybe a few flutters in between. I almost experienced 'sudden death'. On January 27 I had a pacemaker implanted. I then had an endoscopy and my throat is normal, a little narrow near the stomach, but normal. I still have swallowing problems, but the pacemaker seems to ensure that my heart will not pause (stop) again from this vaso vagal response. I think this condition is more common than what is suspected. My endoscopist said Mama Cass died from this.