Diagnostic utility and outcomes of inpatient investigations for syncope in a regional setting

Syncope is a common presentation to the emergency department with a wide spectrum of aetiology. The identification of the underlying cause can be diagnostically challenging, as are the choice of investigations and the decision for inpatient versus outpatient disposition.

This study aimed to evaluate the aetiology of syncope as documented, the diagnostic yield of inpatient investigations and outcomes for adult patients admitted for syncope.

A single-centred, retrospective cohort study was conducted in adult patients admitted for syncope within a 2-year period. A total of 386 patients were identified after exclusion. Information regarding syncope aetiology, investigations and outcomes were established via chart review of electronic records.

The most common cause of syncope was neural-mediated (43%), followed by orthostatic (36.5%) and cardiogenic (20.5%). The investigations performed in order of frequency included: telemetry electrocardiogram (ECG) (75.4%), computed tomography head non-contrast (58.8%), transthoracic echocardiogram (TTE) (20.2%), computed tomography pulmonary angiogram (CTPA) (6.5%), MR brain (3.9%), electroencephalogram (1.3%) and carotid ultrasound (0.3%). Telemetry ECG, TTE and CTPA led to the diagnosis of syncope in a minority of patients only. As a result, 17.5% of patients had a new intervention on discharge, 5.4% were readmitted for syncope and 9.6% of patients died.

In the context of the inpatient evaluation of syncope, this study supports the use of telemetry ECG and TTE. Neuroimaging demonstrates a low diagnostic yield for the cause of syncope, but it may have a role to play in excluding other pathologies. Our study does not support the routine use of CTPA, EEG or carotid ultrasound in the evaluation of syncope.