People With Unexplained Fainting Finally Get Some Answers With Take-Home Device

For people going to emergency departments (EDs) for syncope, an extended ECG monitoring protocol made an eventual diagnosis more likely even though their fainting frequency was ultimately unchanged, according to the ASPIRED trial.

Across several dozen hospitals in the U.K., people with acute unexplained syncope were randomized to immediate 14-day cardiac monitoring — using the BodyGuardian Mini, a small, adhesive, and waterproof continuous heart monitor — or standard care.

The study’s main finding was that at 1 year, the mean number of patient-reported episodes of syncope at 1 year came out similar between groups (1.37 with the intervention vs 1.58 with standard care; incidence rate ratio 0.89, 95% CI 0.68-1.18), reported Matthew James Reed, MD, of the Usher Institute, Edinburgh University in Scotland.

Nonetheless, immediate 14-day cardiac monitoring was associated with major benefits: an intriguing reduction in all-cause death (1.5% vs 2.9%; OR 0.50, 95% CI 0.27-0.93) and better identification of a clinically significant cardiac arrhythmia (22.0% vs 9.0%; OR 2.95, 95% CI 2.28-3.81).

ASPIRED was presented at the European Society of Cardiology (ESC) Congress in Munich. The trial was simultaneously published in the New England Journal of Medicine.

“Applying a 14-day ambulatory cardiac patch monitoring at index ED visit did not reduce patient-reported syncope episodes at 1 year. Early monitoring did, however, more than double arrhythmia diagnosis … and reduced the time to detection from around 55 days to 22 days. More patients also received prompt, targeted treatment, such as permanent pacing and antiarrhythmic drugs,” Reed reported.

“We believe this provides a biologically plausible mechanism for our 1-year survival benefit,” he told the audience.

Reed noted that diagnosing an underlying cardiac arrhythmia remains difficult in patients with syncope who present to the ED; approximately half these patients leave the ED with no identifiable cause for the syncope. The challenge is determining if the syncope has a vasovagal origin, or is due to postural hypotension or a serious cardiac issue such as structural heart disease or arrhythmia.

ASPIRED builds on prior evidence that detection of an arrhythmia in a patient with unexplained syncope is most likely when cardiac monitoring is initiated early, ideally at the index visit to the ED.

“Technically, this is a negative trial. Nevertheless, the ASPIRED trial provided two very important findings. It allowed a higher detection rate of clinically significant arrhythmias in 22% of cases and reduced all-cause mortality by 50%,” said ESC session discussant Michele Brignole, MD, of IRCCS Istituto Auxologico in Milan, Italy.

“However, the direct cause-effect relationship between arrhythmias and all-cause mortality remains uncertain, probably unlikely,” Brignole argued. “My alternative, plausible biological mechanism is that the reduction in all-cause mortality may reflect more thorough investigation following arrhythmia detection, not a direct relationship.”

The ASPIRED investigators reported that all trial participants could be referred for evaluation by a syncope specialist and would be seen ideally within 6 weeks after the index event. Treatment decisions based on the results from the ambulatory heart monitor, including further investigation, were at the discretion of the treating clinician. If a serious cardiac arrhythmia was detected, the patient’s local team was notified within 24 working hours.

ASPIRED was an open-label trial conducted at 45 U.K. hospitals. Researchers had people 16 years or older, with syncope remaining unexplained after an evaluation in the ED, randomized 1:1 to 14-day ambulatory ECG monitoring or to standard care.

Both groups were instructed to record any fainting episode in a paper diary. The intervention group was fitted with the BodyGuardian Mini as soon as possible and was also instructed to press a button on the heart monitor after recovery from any fainting.

The study cohort came out to a total of 2,234 randomized individuals (mean age 58.3 years, 52.1% men). Excluding those lost to follow-up, the investigators had 1,970 patients for the primary analysis.

Reed’s group logged 49 adverse events in the intervention group and eight adverse events among controls. Most of the events in the intervention group were attributable to minor skin irritation.

There was one serious adverse event in each group: one infection of an implantable loop recorder in a patient in the extended monitoring group (resulting in removal of the device), and a hematoma at a pacemaker wound site in a patient in the standard care group (resulting in outpatient administration of antibiotics). Both of these events were judged to be unrelated to the trial intervention, according to the authors.

Limitations of the trial include its open-label design and lower than anticipated rate of recurrent syncope.

The ongoing REMOSYNCED study may provide external validation in a different care setting, Reed and colleagues noted.