Novel Syncope Unit Speeds Diagnosis, Cuts Costs

NEW ORLEANS — Creating a designated syncope unit in the emergency department improves diagnostic yield and dramatically reduces costly hospital admissions for this common condition, Win K. Shen, M.D., reported at the annual scientific sessions of the American Heart Association.

Cardiologists and emergency medicine specialists at the Mayo Clinic teamed up to create the novel syncope unit. Then they tested their innovation in the Syncope Evaluation in the Emergency Department Study (SEEDS), a randomized, prospective, single-center study of 103 patients with syncope. The patients were deemed to be at intermediate risk for adverse cardiovascular outcome according to American College of Emergency Physicians criteria.

Half of the SEEDS participants received routine care in the emergency department. The other half were randomized to the syncope unit, where they underwent up to 6 hours of continuous heart rhythm monitoring along with hourly orthostatic blood pressure measurements, an echocardiographic exam, carotid sinus massage with continuous blood pressure and heart rate monitoring, tilt table testing, and an electrophysiology consultation.

The primary end points in SEEDS, a Mayo Foundation-funded trial, were diagnostic yield and hospital admission rate at the time of dismissal from the emergency department.

A presumptive diagnosis was established in 67% of patients in the syncope unit and 10% of standard-care patients. Hospital admission was required for 43% of syncope-unit patients, but 98% of those who got standard emergency department care.

Patients randomized to the syncope unit collectively spent 64 days in the hospital, compared with 140 days for the standard-treatment group. The 2-year rates of survival and freedom from recurrent syncope were similar in the two groups.

Widespread adoption of the syncope unit model in the nation's emergency departments could have a major clinical and economic impact. An estimated 5% of all emergency department visits are for evaluation of syncope, and syncope accounts for up to 6% of all urgent hospital admissions. Work-up of syncope patients, who are typically asymptomatic by the time they arrive at the emergency department, is often expensive. Indeed, syncope costs the U.S. health care system more than $1 billion annually, according to Dr. Shen, professor of medicine at the Mayo Medical School, Rochester, Minn.

The concept behind the Mayo Clinic's syncope unit is similar to that of the chest pain evaluation units popping up in a growing number of emergency departments. Both syncope and chest pain are common presenting complaints that have numerous potential etiologies; only a minority of patients have a life-threatening condition. Like the chest pain units, the syncope unit protocol involves a period of cardiac monitoring followed by diagnostic testing.

Discussant Eric N. Prystowsky, M.D., said he agrees with the SEEDS investigators' conclusion that the cause of most syncope can be diagnosed in the emergency department, enabling many patients to avoid the expense and inconvenience of hospitalization. But he's not convinced that a specialized syncope unit is required.

“What the patient really needs is a good doctor,” argued Dr. Prystowsky, director of the clinical electrophysiology laboratory at St. Vincent Hospital, Indianapolis, and editor-in-chief of the Journal of Cardiovascular Electrophysiology.

“It doesn't have to be an electrophysiologist, but it has got to be someone trained in the work-up of patients with syncope. If you get a neurologist down there you will have an MRI and an EEG on every patient with neurally mediated syncope. That's not the person you want for the initial evaluation unless the patient has had documented seizures,” Dr. Prystowsky said. “We ought to stop the $20,000 work-ups and get back to basics.”

The goal of the emergency department evaluation of syncope is to rule out the high-risk patient. That process starts with a careful history and physical examination and relies heavily upon a reassuring echocardiogram and ECG. It's important to realize that neurally mediated syncope and orthostatic intolerance to medications are more common than cardiac syncope, even in patients with coronary heart disease.

“If the echo shows good ventricular function and the ECG looks good and the story suggests a noncardiac syncope, I'm OK with doing the rest of the work-up on an outpatient basis. You don't have to do the tilt test right there. If you have a tilt table there, terrific, but I want to remind everybody of one thing about tilts: Do remember that people with very serious cardiac syncope that can lead to sudden death can also have a positive tilt. There have been some very famous legal cases where this has happened,” he noted.