From the Guidelines
Vasovagal syncope symptoms include lightheadedness, dizziness, nausea, sweating, blurred vision, and feeling warm before fainting, and are typically triggered by emotional stress, pain, prolonged standing, or the sight of blood, as noted in the 2019 American Heart Association and American Red Cross focused update for first aid 1. These episodes are characterized by a drop in blood pressure and heart rate, leading to reduced blood flow to the brain and temporary loss of consciousness. Some people experience warning signs like pallor, yawning, or a feeling of impending doom before fainting. After fainting, most people regain consciousness quickly but may feel tired or confused. The symptoms of vasovagal syncope occur because of an overreaction of the autonomic nervous system, causing blood vessels to dilate and heart rate to slow, which reduces blood flow to the brain, as described in the 2017 ACC/AHA/HRS guideline for the evaluation and management of patients with syncope 1. Key symptoms and signs of vasovagal syncope include:
- Lightheadedness
- Dizziness
- Nausea
- Sweating
- Blurred vision
- Feeling warm before fainting
- Pallor
- Yawning
- Feeling of impending doom Treatment typically involves lying down with legs elevated when symptoms begin, avoiding triggers, staying hydrated, and increasing salt intake, as recommended in the 2018 ESC guidelines for the diagnosis and management of syncope 1. For recurrent episodes, medications like fludrocortisone, midodrine, or beta-blockers might be prescribed. Physical counterpressure maneuvers (PCMs) can also be beneficial in preventing syncope, as noted in the 2019 international consensus on cardiopulmonary resuscitation and emergency cardiovascular care science with treatment recommendations 1.
From the Research
Symptoms of Vasovagal Syncope
The symptoms of vasovagal syncope are not explicitly listed in the provided studies. However, the studies discuss the treatment and management of vasovagal syncope, which can be inferred to be related to its symptoms.
Treatment and Management
- The cornerstone of treatment for vasovagal syncope (VVS) is lifestyle modifications, including drinking 2 to 3 liters of fluids per day, consuming 10 grams of NaCl per day, and practicing counter-pressure maneuvers 2.
- Pharmacological interventions, such as midodrine and fludrocortisone, may be necessary for patients who experience life-disturbing attacks despite compliance with lifestyle modifications 2, 3, 4.
- Midodrine and fludrocortisone have been shown to increase 24-h systolic blood pressure (SBP) and reduce SBP drops in patients with symptoms due to hypotension 3.
- Fludrocortisone may be more effective than midodrine in increasing 24-h SBP and reducing SBP drops 3.