Syncope, adult — when imaging is indicated
Recommended: No routine imaging; selective CT head / echo / CTPA by phenotype is the preferred imaging study for syncope, adult — when imaging is indicated. Most syncope (vasovagal, orthostatic) does NOT need imaging.
Recommended study
No routine imaging; selective CT head / echo / CTPA by phenotype
Most syncope (vasovagal, orthostatic) does NOT need imaging. CT head only with head strike, focal deficit, or new headache. Echocardiography when structural heart disease suspected (murmur, exertional syncope, abnormal ECG). CTPA only if PE is on the differential — exertional syncope ± hypoxia.
If the default doesn't apply
Head strike or anticoagulated
CT
CT head without contrast (see head-trauma, anticoag-fall)
No contrast
Exertional syncope or murmur — structural heart disease suspected
Transthoracic echo (see valve-disease, hcm-cardiac)
No contrast
Syncope with chest pain / hypoxia — PE on differential
CT
CTPA (see pe-suspected)
IV contrast
Suspected arrhythmogenic substrate (ARVC, sarcoid)
MRI
Cardiac MRI (see vt-cmr, arvc, cardiac-sarcoid)
IV contrast
Watch-outs
Routine CT head for uncomplicated syncope
Yield is < 2% without head strike, focal deficit, or anticoagulation — don't reflexively scan.
Syncope ≠ TIA
Isolated LOC without focal deficit is rarely cerebrovascular. Don't substitute syncope workup for stroke workup.
Pearls
- San Francisco Syncope Rule / Canadian Syncope Risk Score help target which patients merit cardiac imaging.
- Cardiac MRI is the test for unexplained syncope with suspected structural / infiltrative cardiomyopathy.
- Tilt-table testing is functional, not imaging — image only when structural pathology is on the differential.