"Tell the patient he needs to return to the hospital. Right away."
"Why? He says he feels fine."
"Tell him there's something wrong with his heart," I said. "He has to come back."
Eight hours earlier, at 2 a.m., the patient had come to the emergency room. One of my favorite residents had presented the details of the case.
"Forty-eight-year-old Asian man, passed out watching television," she related in her precise Indian-British diction. "Felt a fullness in the head. The family says they saw him shake, turn blue, and come to a few minutes later. No medical history, really, except that he smokes one pack a day."
"He was watching TV? Doing nothing else?" I asked, dubious.
She was ready for me. "Yes. On his bed at home. I asked him twice."
No one just passes out in bed.
Fainting, known to doctors as syncope (SIN-kuh-pee), is what happens when a disruption occurs in the blood flow to the brain. In bipeds like us, the brain depends on a finely tuned vascular system. To adjust heart rate and blood pressure to changes in posture, the body employs two competing nervous systems, the sympathetic and the parasympathetic. The sympathetic is like the body's internal espresso machine: revving things up using adrenaline and the fight-or-flight reflex. The parasympathetic slows things down, delivering signals via the long, winding vagus (Latin for "wandering") nerve that runs from the base of the brain down through the esophagus and into the gut.
In young people, fainting rarely signals disease. If the right noxious stimulus—like the sight of blood—comes along, the sympathetic network might abruptly bump up the heart rate. To reestablish calm, the vagus nerve starts firing. Sometimes, especially if you are standing still, the body's calming response can prompt a faint, also known as vasovagal syncope. If this patient had fainted at rest, I needed to know if an unsettling event had somehow triggered too much of a parasympathetic response, causing vasovagal syncope. So I went to see the patient.
Via the translator, I asked, "Were you having a fight at home? Anything upset you?"
"No," came the reply.
"Have you been getting enough sleep? Are you working too hard?"
"And you were feeling perfectly well until you fainted?"
The translator went back and forth a few times with the whole family. "He says he felt his heart beating fast, then felt dizzy just before he fainted."
That would be the initial bump in heart rate that provokes the vagus to respond. Something was upsetting this man.
"Where do you work?"
"Any problems today?"
A much longer exchange followed. "He says he did something very bad at work today. His boss yelled at him."
Bingo, the smoking gun. The resident looked impressed.
"It's all in the history," I said.
We checked the electrocardiogram. "Looks like a right bundle," she said, pointing out a pattern.
In a normal EKG, each spike is followed closely by a valley, reflecting electrical discharge across the heart. A right bundle branch block is when the spike and valley are accompanied by another, wider spike that indicates sluggish electrical conduction through the right ventricle.
"Normal variant," I assured her.
"What about this S-T segment?" she asked, pointing her finger at the line coming off the last spike. Instead of dropping down, it stayed up like a billowing sail.
"I don't know," I answered, "but you see funny things sometimes. Rule number one: In vasovagal syncope, history rules. Discharge him."