Autonomic syncope admissions: the gap between guideline and real life

Background

The majority of syncope emergency department (ED) presentations is due to autonomic syncope, which comprises reflex syncope and orthostatic hypotension. Despite the European Society of Cardiology (ESC) guidelines most patients with autonomic or unexplained low risk syncope are still admitted. Therefore we studied the indications for, and the determinants of, clinical admission in the prospective SYNERGY trial.

Methods

We performed a sub-analysis of the SYNERGY trial (a pre-post analysis on the implementation of the 2018 ESC guidelines in the ED). We included all subjects visiting the ED with an adjudicated diagnosis of autonomic or unexplained low risk syncope. Diagnostic adjudication was performed by an expert committee after one year critical follow-up. We computed guideline-based initial management in the ED, using the initial diagnosis established by the ED physician combined with a retrospective ESC guideline based risk stratification of (low-risk, intermediate-risk, high-risk). Furthermore, correspondence regarding the ED visit was analyzed for the indication of admissions. Then, we compared this guideline based management to effectuated patient management in the ED.

Results

521 patients were enrolled in the SYNERGY trial, 74.5% (N=388/521) were adjudicated as autonomic-syncope patients, of whom 39.8% (n=153) were admitted. Admissions defined as indicated (66.0%, 101/153) were due to syncope related illness (31.4%, n=48/153), cardiac observation indication (15.7%, n=24/153), syncope unrelated illness (9.2%, n=14/153), injury (5.9%, n=9/153), waiting for diagnostics (2.0%, n=3/153) or social indication (2.0%, n=3/153). Admissions defined as not indicated were admissions of patients without any stated risk features where no indication was found in the documentation besides monitoring (34.0%, n=52/153).

Telemetry monitoring was used in 53.5% (n=54/101) of patients with an indication for admission and in 98.1% (n=51/52) of patients without indication for admission.

Determinants for admission were age (OR:1.028/year, 95%CI:1.011-1.046, p=0.001), illness/diagnostics/consulting unrelated to the syncopal event itself (OR:9.295, 95%CI:4.272-20.223, p<0.001), any ECG-abnormalities (OR:1.931, 95%CI:1.129-3.303, p=0.016). While performing an active standing-test in the ED was associated with a lower likelihood of admission (OR:0.441, 95%CI:0.238-0.817, p=0.009).

Post-hoc computed guideline-based management would have decreased hospitalization (-34.0%) and in hospital telemetry-monitoring(-69.5%).

Conclusions

Among autonomic syncope patients in the ED, hospital admission occurred in 39.8% of cases, of which one-third were not guideline-indicated. Older age, unrelated diagnostic findings, and any ECG abnormalities increased the odds of admission, while performing an active standing-test reduced it. Optimizing the initial evaluation process in the ED may improve guideline adherence and reduce unnecessary admissions.Guideline versus real world managementAdmission indications