Is it normal to experience terror and pain after fainting (syncope)?

From the Guidelines

It is not normal to experience terror and pain when coming out of syncope (fainting). Typically, recovery from syncope involves a gradual return to consciousness, possibly with brief confusion, but not terror or pain. These symptoms suggest something other than simple fainting may be occurring. If you're experiencing terror or pain upon regaining consciousness, you should seek medical evaluation promptly. A healthcare provider can determine if these symptoms indicate an underlying condition such as seizures, cardiac arrhythmias, or psychological factors. During evaluation, your doctor may order tests like an electrocardiogram (ECG), echocardiogram, or electroencephalogram (EEG) to identify potential causes. Normal syncope recovery usually involves feeling tired, weak, or slightly disoriented for a short period, but acute distress is not expected. The autonomic nervous system typically rebalances itself gradually after a fainting episode, which should not involve significant pain or emotional distress. According to the 2017 ACC/AHA/HRS guideline for the evaluation and management of patients with syncope 1, syncope is defined as a symptom that presents with an abrupt, transient, complete loss of consciousness, associated with inability to maintain postural tone, with rapid and spontaneous recovery. The presumed mechanism is cerebral hypoperfusion.

Some key points to consider when evaluating syncope include:

• The patient's medical history, including any previous episodes of syncope or related conditions
• The presence of any underlying cardiac or neurological conditions
• The use of any medications that may contribute to syncope
• The results of any diagnostic tests, such as ECG or EEG
• The presence of any identifiable triggers or prodromal symptoms

In terms of specific conditions that may cause syncope, the 2017 guideline 1 notes that cardiac syncope is caused by bradycardia, tachycardia, or hypotension due to low cardiac index, blood flow obstruction, vasodilatation, or acute vascular dissection. Noncardiac syncope, on the other hand, is due to noncardiac causes, including reflex syncope, orthostatic hypotension, volume depletion, dehydration, and blood loss. Reflex syncope, also known as neurally mediated syncope, is due to a reflex that causes vasodilation, bradycardia, or both. Vasovagal syncope (VVS) is the most common form of reflex syncope, mediated by the vasovagal reflex, and is often preceded by identifiable triggers and/or a characteristic prodrome.

Overall, while some discomfort or disorientation is common after a fainting episode, experiencing terror or pain is not typical and should prompt further evaluation to rule out any underlying conditions that may be contributing to these symptoms.

From the Research

Syncope and Associated Symptoms

• Syncope is a short-term transient loss of consciousness, characterized by rapid onset and complete spontaneous recovery 2
• The pathophysiological mechanisms underlying vasovagal syncope, the most common form of syncope, remain obscure 2, 3, 4
• Triggers of vasovagal syncope are likely to be protean, and many potential central and peripheral triggers have been identified 4

Experience of Terror and Pain

• There is no direct evidence in the provided studies that specifically addresses the experience of terror and pain coming out of syncope
• However, it is known that vasovagal syncope can be a frightening experience for patients, and the loss of consciousness can be accompanied by various symptoms such as dizziness, nausea, and sweating 3, 4
• The studies focus more on the pathophysiological mechanisms, diagnosis, and management of vasovagal syncope, rather than the subjective experience of patients during or after the episode 2, 3, 4, 5, 6

Diagnosis and Management

• The diagnosis of vasovagal syncope can be made based on history, and a tilt test can be offered to patients with unclear diagnosis 3
• The initial management of vasovagal syncope is primarily conservative, and pacing may be considered in some cases 3
• A 12-lead electrocardiogram (ECG) is recommended for the initial evaluation of patients with suspected syncope, and it may disclose an arrhythmia associated with a high likelihood of syncope 5