From the Guidelines
Syncope, commonly known as fainting, is caused by a temporary reduction in blood flow to the brain, and the most recent guidelines recommend physical counterpressure maneuvers (PCMs) as a first aid intervention to help prevent syncope, especially in cases of vasovagal or orthostatic origin 1.
Causes of Syncope
The causes of syncope can be categorized into several groups, including:
- Vasovagal reactions, which are triggered by emotional stress, pain, or standing for long periods
- Cardiac issues, such as arrhythmias, structural heart disease, or valve problems
- Orthostatic hypotension, which is a blood pressure drop when standing
- Neurological conditions, such as seizures or stroke
Treatment of Syncope
Treatment of syncope depends on the underlying cause. For vasovagal syncope, lifestyle modifications like avoiding triggers, increasing salt and fluid intake, and physical counterpressure maneuvers (leg crossing, muscle tensing) are recommended 1. Orthostatic hypotension may be managed by slowly changing positions, wearing compression stockings, and increasing fluid intake. Cardiac syncope requires specific treatments addressing the underlying heart condition, which might include medications (beta-blockers, antiarrhythmics), pacemaker implantation for bradycardia, or implantable cardioverter-defibrillators for dangerous arrhythmias.
Importance of Accurate Diagnosis
The key to effective treatment is accurate diagnosis through a thorough medical history, physical examination, and appropriate tests like electrocardiogram, echocardiogram, or tilt-table testing 1. Patients with recurrent syncope should be evaluated by a healthcare provider to identify the cause and prevent future episodes, as some forms of syncope, particularly cardiac-related, can indicate serious underlying conditions.
Recent Guidelines
Recent guidelines from the American Heart Association and American Red Cross recommend the use of PCMs as a first aid intervention to help prevent syncope, especially in cases of vasovagal or orthostatic origin 1. These maneuvers can help increase blood pressure and improve symptoms, and can be performed by individuals experiencing presyncope or by first aid providers.
From the Research
Causes of Syncope
- Syncope, also known as "blacking out," can be caused by various factors, including orthostatic hypotension, neurocardiogenic syncope, and autonomic failure 2.
- Orthostatic hypotension occurs when blood pressure drops suddenly upon standing, leading to reduced blood flow to the brain and potential syncope 3.
- Neurocardiogenic syncope is a type of syncope that occurs when the nervous system overreacts to certain triggers, such as stress or pain, causing blood vessels to dilate and heart rate to slow 2.
Treatments for Syncope
- Treatment for syncope depends on the underlying cause, but may include medications such as fludrocortisone, midodrine, and beta-blockers 2, 3, 4.
- Fludrocortisone is a mineralocorticoid analog that promotes sodium reabsorption and can help increase blood pressure in patients with orthostatic hypotension 3, 5.
- Midodrine is an alpha-1 adrenergic agonist that can help increase blood pressure and reduce symptoms of orthostatic hypotension 2, 5.
- Beta-blockers, such as bisoprolol, can help reduce the risk of syncope in patients with neurocardiogenic syncope 4.
Diagnostic Tests
- The tilt table test (TTT) is a non-invasive test used to diagnose syncope and orthostatic intolerance 6.
- The TTT involves strapping the patient to a table that tilts to an upright position, allowing healthcare providers to monitor blood pressure and heart rate responses to orthostatic stress 6.
- Implantable loop recorders (ILR) can also be used to document cardioinhibitory reflex syncope and guide treatment decisions 6.