Health & Medicine / Heart Disease

After the shift, one of our cardiologists called to tell me that he had reviewed the previous day's EKGs, and my patient's stood out. "Was he admitted?"

"No, why?" My own heartbeat surged.

"It's a Brugada's."

"Huh?" A long-ago lecture flashed through my head. The speaker had shown the slide of an EKG, saying, "This is Brugada syndrome. I have to tell you about it, but you'll never see it."

"There is a risk of sudden death," said the cardiologist.

I grabbed an article from my files. The patient's EKG was the spitting image of a patient with Brugada.

In the Philippines they call it bangungut, meaning "to rise and moan in sleep." In Thailand it is lai tai; in Japan, pokkuri; in the United States, sudden unexpected nocturnal death syndrome, or (this being the land of acronyms) SUNDS. In the 1940s, doctors had puzzled over a bizarre syndrome in Southeast Asia that woke healthy young men (and very few women) from sleep with night terrors, then killed them. At the end of the Vietnam War, with the refugee exodus from the area, case reports in the United States began to filter in. At first, many doctors speculated that it was a type of extreme stress reaction.

In 1992, the doctor brothers Josep and Pedro Brugada contradicted that notion in a paper on eight European patients who had suffered unexplained fainting spells. While being monitored in the hospital, all eight came within seconds of death. Their heart monitors recorded normal heartbeats suddenly degenerating into ventricular fibrillation, the chaotic rhythm that wipes out the heart's pumping action. Happily, all were resuscitated. Nothing in the patients' history matched other known causes of sudden cardiac death. The signature of the mystery syndrome was a distinctive shared EKG pattern: the spike-valley-spike of a right bundle branch block, with the final segment billowing out abnormally as my patient's did.

Brugada syndrome is mercifully rare. In Japan, under 1 percent of the population has the EKG pattern; in the United States, less than half a percent does. Of those with only the EKG findings, most will never have a problem. However, anyone who has fainted for no reason, or has relatives who died young, might be at risk for sudden death. Among the eight patients in the Brugadas' study, two had a relative who had died without warning.

In 1998 the hereditary defect was traced to a gene that codes for a protein component of sodium channels in heart cells. The job of a heart cell is to contract, like a miniature muscle, and to pass an electrical impulse to its neighbor. In response to the electrical impulse, doughnut-shaped proteins embedded in the neighboring cell membrane open, and charged ions like sodium move in and out of the cell, propagating the charge. In Brugada syndrome, the sodium ions enter too slowly because the channel is defective. The defect is most pronounced in cells on the surface of the heart, which is reflected by a puffed-out S-T segment on an EKG. No one knows why these problems don't emerge until the patients are over 30.

Heart cells, also called myocytes. In Brugada's patients, myocytes have defective membrane channels that slow the influx of sodium ions. (Courtesy of Gonda (Goldschmied) Neuroscience and Genetics Research Center, University of California, Los Angeles)

Something similar goes wrong in a typical heart attack. Most deaths from heart attacks stem from ventricular fibrillation caused by electric eddies and short circuits—in other words, disordered conduction. Prompt treatment with one of the new automated external defibrillators works very well because the electric charge reboots the heart and brings its contractions back into sync.

In a normal person who faints from a vagal overload, the sympathetic network kicks back in, and all is well. But in a person with Brugada, nighttime vagal activity can generate uneven electrical conduction in the heart. The result is fainting from chaotic, ineffectual heart rhythms like ventricular tachycardia, or even death from full-blown fibrillation.

After admitting the patient, the next question was whether to go straight for an implantable defibrillator—the only effective treatment—or insert a catheter into his heart and electrically test the likelihood of fibrillation.

The debate ended that night. At 1 a.m. the patient's monitor showed multiple runs of ventricular tachycardia, the near-chaotic rhythm that often precedes fibrillation. Without protest, he agreed to be transferred uptown for that defibrillator.

The next day the resident had that "have I got a follow-up for you" look.

"I heard," I said with a grin. "Rule number two: Beware of old docs who think they know all the rules."

Tony Dajer is interim chief of the emergency department at New York Downtown Hospital. The cases described in Vital Signs are real, but the authors have changed patients' names and other details to protect their privacy.

Previous Vital Signs columns: