From the Guidelines
Presyncope, characterized by lightheadedness, dizziness, and feeling faint without complete loss of consciousness, requires immediate attention and a thorough evaluation through a detailed history, focusing on the circumstances surrounding episodes, including timing, position changes, exertion, emotional triggers, and associated symptoms, as recommended by the 2024 American Heart Association and American Red Cross guidelines for first aid 1. When taking a presyncope history, it is essential to ask about:
- Duration and frequency of episodes
- Recovery time
- Any warning signs
- Medication history, particularly cardiovascular medications, antihypertensives, and those affecting heart rate or blood pressure
- Relevant medical conditions such as cardiac arrhythmias, structural heart disease, diabetes, or neurological disorders
- Family history of cardiac conditions or sudden death
- Hydration status, recent illness, and alcohol or substance use This comprehensive approach helps distinguish between common causes like vasovagal reactions, orthostatic hypotension, cardiac arrhythmias, or medication effects, guiding appropriate diagnostic testing and management strategies. According to the 2019 American Heart Association and American Red Cross focused update for first aid, physical counterpressure maneuvers (PCMs) can be beneficial in preventing syncope in individuals experiencing presyncope of vasovagal or orthostatic origin 1. The 2017 ACC/AHA/HRS guideline for the evaluation and management of patients with syncope also emphasizes the importance of a thorough history and physical examination in evaluating patients with syncope or presyncope 1. In summary, a thorough evaluation and history are crucial in managing presyncope, and physical counterpressure maneuvers (PCMs) can be a useful first aid intervention to prevent syncope in individuals experiencing presyncope of vasovagal or orthostatic origin, as recommended by the 2019 American Heart Association and American Red Cross focused update for first aid 1.
From the Research
Presyncope History
- Presyncope is a condition that precedes syncope, characterized by similar symptoms but without the actual loss of consciousness 2.
- Patients with presyncope have similar prognoses to those with syncope and should undergo a similar evaluation 2.
- A detailed history is crucial in evaluating patients with presyncope, as it can help identify the underlying cause and guide further management 3, 4.
- The initial assessment for patients presenting with presyncope includes a physical examination, electrocardiography, and a thorough history 2.
- In some cases, presyncope can be prevented or managed with non-pharmacological interventions, such as physical counter-pressure maneuvers (PCM) or changes in body position 5.
Evaluation and Management
- A standardized approach to evaluating presyncope can help reduce hospital admissions and medical costs, while increasing diagnostic accuracy 2.
- Laboratory testing and neuroimaging have a low diagnostic yield and should only be ordered if clinically indicated 2.
- Several clinical decision rules can be used to assess the short-term risk of death and the need for hospital admission in patients with presyncope 2.
- High-risk patients with cardiovascular or structural heart disease, history concerning for arrhythmia, abnormal electrocardiographic findings, or severe comorbidities should be admitted to the hospital for further evaluation 2.
Non-Pharmacological Interventions
- Physical counter-pressure maneuvers (PCM) may provide benefit for preventing syncope during acute episodes of presyncope and can be tried in the first aid setting 5.
- PCM has been shown to improve symptoms and blood pressure in patients with presyncope, with no reported adverse events 5.
- However, the evidence for non-pharmacological interventions is limited, and more research is needed to fully understand their effectiveness 5.