From the Guidelines
The workup for chronic presyncope should begin with a thorough history and physical examination, focusing on cardiovascular, neurological, and metabolic causes, as recommended by the most recent guidelines 1. The initial evaluation should include orthostatic vital signs, electrocardiogram (ECG), and basic laboratory tests including complete blood count, basic metabolic panel, and thyroid function tests.
- Key components of the history and physical examination include:
- Cardiovascular history, including symptoms of heart failure, arrhythmias, or valvular disease
- Neurological history, including symptoms of seizures, stroke, or multiple sclerosis
- Metabolic history, including symptoms of diabetes, thyroid disease, or adrenal insufficiency
- Initial testing should also include:
- Orthostatic vital signs to evaluate for orthostatic hypotension
- ECG to evaluate for cardiac arrhythmias or conduction abnormalities
- Basic laboratory tests to evaluate for metabolic disorders or anemia If the initial evaluation is inconclusive, additional testing may include:
- 24-hour Holter monitoring or 30-day event monitoring to capture cardiac arrhythmias
- Echocardiogram to assess structural heart disease
- Tilt-table testing to evaluate for vasovagal syncope or orthostatic hypotension In selected cases, neurological evaluation with electroencephalogram (EEG) or brain imaging may be warranted if seizures are suspected 1. Carotid sinus massage might be considered in older patients with symptoms suggesting carotid sinus hypersensitivity. Exercise stress testing is appropriate when symptoms are exercise-related. Management depends on the underlying cause but may include hydration, salt intake, compression stockings, and medication adjustments for orthostatic hypotension; beta-blockers, fludrocortisone, or midodrine for vasovagal syncope; and specific treatments for cardiac arrhythmias or structural heart disease. Patients should be counseled on safety measures to prevent falls and injuries during episodes, including avoiding triggers, changing positions slowly, and maintaining adequate hydration.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Diagnosis of Chronic Near-Syncope (Presyncope)
The workup for chronic near-syncope (presyncope) involves a detailed initial evaluation with:
- Medical history
- Physical examination
- Resting electrocardiogram to rule out cardiac syncope 2, 3
- Measurement of supine and standing blood pressure and heart rate to identify the pattern of hemodynamic regulation during orthostatic stress 2
Classification and Evaluation
Presyncope can be classified into different types, including:
- Neurally mediated
- Cardiac
- Orthostatic hypotension 3 A standardized approach to evaluation can help reduce hospital admissions and medical costs, and increase diagnostic accuracy 3 The initial assessment may diagnose up to 50% of patients and allows immediate short-term risk stratification 3
Further Testing and Management
Additional testing may be required in patients without a clear diagnosis after the initial evaluation 2 Laboratory testing and neuroimaging have a low diagnostic yield and should be ordered only if clinically indicated 3 Management of patients should focus on improving symptoms and functional status, and not targeting arbitrary hemodynamic values 2 An individualized structured and stepwise approach should be taken for treatment, starting with:
- Patient education
- Lifestyle modifications
- Use of physical counter-pressure maneuvers and devices to improve venous return 2, 4 Pharmacologic interventions should be added only when conservative approaches are insufficient to improve symptoms 2
Immediate Interventions
Physical counter-pressure maneuvers (PCM) may provide benefit for prevention of syncope during acute episodes of presyncope and may be tried in the first aid setting 4 PCM can improve symptom improvement and vital signs, including blood pressure 4