Syncope is a transient loss of consciousness caused by transient cerebral hypoperfusion. The condition encompasses several mechanistic categories that clinicians use to frame evaluation and treatment. The principal mechanisms described are reflex (neurally mediated) syncope, orthostatic hypotension–related syncope, and cardiac syncope. Each mechanism reflects different pathophysiologic processes that have implications for diagnosis, risk assessment, and management.
Accurate diagnosis of syncope relies primarily on meticulous history taking and a focused physical examination. A detailed history should characterize the event, prodromal symptoms, context (eg, posture, activity, triggers), past medical history, medications, and any antecedent or subsequent injuries. The physical examination should assess cardiovascular and neurologic status and include orthostatic blood-pressure measurements when indicated.
Because syncope results from transient cerebral hypoperfusion, correlating the patient’s reported features with likely pathophysiologic mechanisms is central to clinical reasoning. The combination of history elements and examination findings often directs the clinician to the most likely category (reflex, orthostatic, or cardiac) and thus informs which diagnostic tests are most appropriate.
Diagnostic testing for syncope should be guided by clinical risk stratification rather than routine, undirected testing. Electrocardiography is among the evaluations referenced in the context of syncope assessment and is a component of cardiology standards for patients with suspected cardiac causes. The choice and urgency of further testing — such as cardiac monitoring, autonomic testing, imaging, or specialist referral — depend on the identified or suspected mechanism and on whether the patient has features that indicate higher risk for adverse outcomes.
Early identification of high-risk features is emphasized as critical for preventing adverse cardiovascular events. The approach prioritizes targeted investigations that have a reasonable pretest probability of altering diagnosis or management, minimizing unnecessary tests and focusing resources on evaluations likely to identify treatable causes or risk markers.
Management of syncope is determined by the underlying mechanism and by the patient’s risk profile. Therapeutic goals include reducing the frequency of recurrent events and minimizing the risk of injury during episodes. For reflex and orthostatic causes, management focuses on measures appropriate to the physiologic disturbance; for cardiac causes, management may include interventions aimed at treating cardiac disease or arrhythmias.
Because the management strategy is mechanism-specific, correctly categorizing the cause through history, examination, and targeted testing is essential. The clinical emphasis is on individualized care guided by the diagnosis and on secondary prevention approaches aligned with cardiology practice standards when cardiac disease is implicated.
In older patients, syncope may present atypically and can manifest as unexplained falls rather than as classic transient loss of consciousness. Clinicians should maintain a high index of suspicion for syncope when assessing older adults with falls, particularly when the circumstances or associated features suggest a transient loss of consciousness.
Assessment in older patients should include careful review of medications, evaluation for orthostatic hypotension, and consideration of comorbid conditions that may contribute to cerebral hypoperfusion. Early recognition of high-risk features in this population is particularly important because of the higher likelihood of adverse cardiovascular outcomes and injury.
Syncope is a common and clinically important presentation that reflects transient cerebral hypoperfusion with multiple potential mechanisms. The priority in evaluation is thorough history taking and physical examination to guide risk stratification and the selection of targeted diagnostic tests. Treatment is mechanism-directed, aiming to prevent recurrence and injury. Special attention is needed for older adults, in whom syncope may present as unexplained falls, and for early identification of high-risk features to prevent adverse cardiovascular outcomes.
Note: This summary is based on the abstract and bibliographic information provided for the referenced review. Specific diagnostic algorithms, testing thresholds, and therapeutic interventions cited in full-text guidelines or the full article were not reported in the available source text and therefore are not included here.