What is the treatment for syncope?

Treatment of Syncope

Treatment of syncope must be directed at the underlying cause and mechanism, with the primary goals being prevention of recurrence, limitation of physical injuries, and in cardiac cases, reduction of mortality risk. 1

Initial Treatment Approach Based on Syncope Type

Reflex (Neurally-Mediated) Syncope

For vasovagal and situational syncope, education and lifestyle modifications are the cornerstone of treatment, with physical counterpressure maneuvers emerging as first-line therapy for patients with prodromal symptoms. 1

Lifestyle Measures (First-Line Treatment)

• Patient education and reassurance about the benign nature of the condition is essential 1
• Trigger avoidance: hot crowded environments, volume depletion, prolonged standing, venipuncture when possible 1
• Recognition of prodromal symptoms (weakness, lightheadedness, visual changes) to allow early intervention 1
• Increased salt and fluid intake (sport drinks, salt tablets) as volume expanders 1
• Discontinuation or reduction of vasodilators (alpha-blockers, diuretics, alcohol) that enhance susceptibility 1, 2

Physical Counterpressure Maneuvers

• Isometric leg crossing or hand grip with arm tensing can induce significant blood pressure increases during impending syncope 1, 2
• These maneuvers allow patients to avoid or delay loss of consciousness in most cases with recognizable prodromal symptoms 1
• Proven effective in multicentre prospective trials with 223 patients 1

Tilt Training

• Progressively prolonged periods of enforced upright posture may reduce syncope recurrence in highly motivated patients with recurrent symptoms 1

Pharmacological Treatment

Beta-blockers are NOT recommended for vasovagal syncope, as five long-term controlled studies have failed to show efficacy. 1

• Midodrine (alpha-agonist vasoconstrictor) showed benefit in short-term controlled studies in elderly patients with severe vasovagal hypotensive syncope, though not placebo-controlled 1
• Etilephrine was studied in the VASIS trial and proved ineffective 1
• Fludrocortisone (mineralocorticoid) can be used for volume expansion, though formal evidence is limited 3
• Most pharmacological agents have failed to show benefit over placebo in long-term controlled trials 1

Cardiac Syncope

In patients with cardiac syncope, treatment must address both the underlying structural disease and the arrhythmic mechanism to reduce mortality risk. 1

Arrhythmic Causes

• Permanent pacing is indicated for symptomatic bradycardia, AV block, or sinus node dysfunction causing syncope 1
• Implantable cardioverter-defibrillator (ICD) is indicated for ventricular tachycardia causing syncope, particularly in patients with structural heart disease or inherited cardiomyopathies 1
• Catheter ablation or antiarrhythmic drugs may be needed for supraventricular tachycardias or when ICD shocks occur too late to prevent loss of consciousness 1

Structural Heart Disease

• Surgical intervention is indicated for severe aortic stenosis or atrial myxoma causing syncope 1
• Revascularization and/or pharmacological therapy for syncope associated with myocardial ischemia 1
• ICD implantation is warranted in hypertrophic cardiomyopathy with syncope to prevent sudden cardiac death 1
• Treatment of acute cardiovascular disease (pulmonary embolism, myocardial infarction, tamponade) should be directed at the underlying process 1

Orthostatic Hypotension

Treatment focuses on volume expansion, avoidance of precipitating factors, and vasoconstrictor agents when conservative measures fail. 1

• Avoid rapid positional changes from supine to standing 3
• Increased sodium and fluid intake 3
• Discontinue or adjust medications that lower blood pressure (diuretics, alpha-blockers, vasodilators) 1, 2
• Midodrine (alpha-agonist) can be used with caution, starting at 2.5 mg in patients with renal impairment, avoiding doses within 3-4 hours of bedtime to prevent supine hypertension 4
• Fludrocortisone (mineralocorticoid) for volume retention 3

Situational Syncope (e.g., Cough Syncope)

Direct suppression of the underlying trigger is the primary treatment. 2

• Identify and treat the underlying cause of cough (respiratory infections, asthma) 2
• Opioid-containing cough suppressants (dihydrocodeine, hydrocodone) for direct cough suppression 2
• Patient education about trigger avoidance and recognition of prodromal symptoms 2

When Additional Treatment is Necessary

More aggressive treatment should be considered when: 1

• Very frequent syncope significantly alters quality of life 1
• Recurrent syncope occurs without or with very short prodrome, exposing patients to trauma risk 1
• Syncope occurs during high-risk activities (driving, machine operation, flying, competitive athletics) 1, 2

Important Caveats

• Even with effective cardiac treatment (e.g., ICD), patients may remain at risk for syncope recurrence because only the sudden cardiac death risk is addressed, not necessarily the mechanism of syncope 1
• Device malfunction (pacemaker battery depletion, lead failure, pacemaker syndrome) requires device reprogramming or replacement 1
• Psychiatric assessment is recommended in patients with frequent recurrent syncope, multiple somatic complaints, and concerns for stress, anxiety, or psychiatric disorders 1