From the Guidelines
Acute syncope in adolescent males is most commonly caused by vasovagal syncope (VVS), which accounts for 33% to 80% of cases, followed by cardiac causes, orthostatic hypotension, and other less common etiologies. The evaluation of syncope in this population should prioritize identifying cardiac causes, which, although less common (1.5% to 6% of cases), can be life-threatening [ 1 ]. According to the 2017 ACC/AHA/HRS guideline for the evaluation and management of patients with syncope, a detailed medical history, physical examination, family history, and a 12-lead ECG are recommended for all pediatric patients presenting with syncope [ 1 ].
Common Causes of Acute Syncope
- Vasovagal Syncope (VVS): The most common cause, often triggered by emotional stress, pain, or prolonged standing [ 1 ].
- Cardiac Causes: Although less common, these are more serious and include arrhythmias, structural heart abnormalities, and conditions like hypertrophic cardiomyopathy [ 1 ].
- Orthostatic Hypotension: A drop in blood pressure upon standing, which can be exacerbated by dehydration, medication, or autonomic dysfunction [ 1 ].
- Dehydration and Overheating: Particularly relevant in athletic individuals or those exposed to hot environments, which can reduce blood volume and trigger fainting [ 1 ].
- Medication Side Effects: Certain medications can affect blood pressure or heart rate, leading to syncope [ 1 ].
- Neurological Conditions: Seizures or other neurological disorders can sometimes present with symptoms mimicking syncope [ 1 ].
Evaluation and Management
The approach to a teenage boy with syncope should include:
- A thorough medical history to identify potential triggers or underlying conditions [ 1 ].
- Physical examination to assess for signs of cardiac disease or other underlying conditions [ 1 ].
- Family history to identify potential genetic predispositions to cardiac conditions [ 1 ].
- A 12-lead ECG as an initial diagnostic step to evaluate for cardiac causes [ 1 ].
- Further cardiac testing (e.g., echocardiogram, stress test) may be indicated based on the initial evaluation and risk factors [ 1 ].
- Education on symptom awareness and avoidance of precipitating factors for those diagnosed with VVS [ 1 ].
From the Research
Common Causes of Acute Syncope in Adolescent Males
The common causes of acute syncope in adolescent males can be identified through a thorough history and physical examination.
- Most syncope is vasovagal, which is benign and does not require extensive investigation 2, 3.
- The prodrome and the circumstances around which the event occurred are the most important aspects of the history 2.
- Syncope occurring midexertion suggests a cardiac etiology 2.
- A family history of sudden death in the young or from unknown causes can be a red flag 2.
Diagnostic Approach
- The electrocardiogram is the most frequently ordered test, but the yield is low and the test is not cost-effective when applied broadly to a population of patients with syncope 2.
- An electrocardiogram is recommended when the history is not suggestive of vasovagal syncope and there are features suggestive of a cardiac cause 2.
- For most patients with syncope, medical testing is not required and lifestyle modifications without medications suffice to prevent recurrences 2, 3.
- Lifestyle measures including aggressive hydration, dietary salt, and an exercise program can be effective in treating neurally mediated hypotension 3.
High-Risk Conditions
- Care must be made to find uncommon and potentially fatal causes of syncope in pediatric patients 4.
- The primary purpose of evaluation of the patient with syncope is to determine whether the patient is at increased risk for death and needs either admission to the hospital or an expedited outpatient evaluation 4.
- A significant majority of patients with serious underlying cardiac conditions can be identified with careful screening by detailed patient history, comprehensive physical examination, and electrocardiogram (ECG) 5.