EpistemisLipotimia (Presyncope)
Specialty: Cardiovascular.
Why it occurs
- Severe aortic stenosis with fixed cardiac output on exertion
- Cardiac arrhythmias (severe bradycardia, high-grade atrioventricular blocks, ventricular tachycardia)
- Neurogenic or drug-induced orthostatic hypotension
- Obstructive hypertrophic cardiomyopathy
- Submassive pulmonary embolism with antegrade flow limitation
- Hypersensitive carotid sinus syndrome
Initial workup
High resolution 12-lead electrocardiogram to identify arrhythmias or channelopathies; Two-dimensional transthoracic echocardiogram to rule out structural or obstructive heart disease; Continuous 24- to 48-hour ambulatory electrocardiographic monitoring (Holter ECG) or implantation of a long-term subcutaneous event recorder in cases of suspected paroxysmal arrhythmia; Tilt table test if dysautonomic component or vasovagal syncope is suspected.
red flags
Recurrent lipothymia triggered by physical effort, or preceded by rapid and irregular palpitations, oppressive chest pain, sudden dyspnea, or occurring in a recumbent position. Likewise, presyncope associated with a family history of sudden death at an early age, or with electrocardiographic findings such as prolongation of the QT interval, left bundle branch block, or elevation of the ST segment in right leads (Brugada syndrome) is of high alarm. Indicates imminent risk of arrhythmic syncope or sudden cardiovascular death.
Standard management
- Fludrocortisone — synthetic mineralocorticoid indicated to increase plasma volume in patients with refractory neurogenic orthostatic hypotension; 0.1 mg once daily orally, monitoring blood pressure and serum potassium
- Midodrine — peripheral alpha-1 adrenergic agonist indicated for refractory orthostatic hypotension; 2.5 to 10 mg three times a day orally, avoiding the last dose before bed due to risk of supine hypertension
- Atenolol — beta blocker useful in obstructive hypertrophic cardiomyopathy to reduce the gradient in the ventricular outflow tract; 25 to 50 mg once daily orally
- Ivabradine (inhibitor of the If current of the sinus node, useful in postural orthostatic tachycardia syndrome; 5 mg twice a day orally).
Educational guidance for study. It is NOT a prescription recommendation. The actual choice depends on the cause, the patient, and current guidelines.
- Area
- Cardiovascular
- Listed causes
- 6
- Treatment options
- 4