What is the management for a patient with a positive tilt table test with nitroglycerin and tachycardia?

From the Guidelines

Management for a patient with a positive tilt table test with nitroglycerin and tachycardia typically involves a combination of non-pharmacological and pharmacological interventions, with a focus on preventing the paradoxical vasodilation and/or bradycardia that occurs during vasovagal episodes. The patient's elevated heart rate of 132 during the test suggests a need to address the tachycardia response, which can be achieved through pharmacological therapy such as beta-blockers like metoprolol (25-100mg twice daily) 1. Non-pharmacological measures include:

• Adequate hydration with 2-3 liters of fluid daily
• Increased salt intake (8-10g/day) if not contraindicated
• Physical counterpressure maneuvers (leg crossing, arm tensing)
• Regular exercise to improve orthostatic tolerance For patients with recurrent episodes, pharmacological therapy may also include:
• Fludrocortisone (0.1-0.2mg daily) to enhance sodium retention and increase blood volume
• Midodrine (2.5-10mg three times daily) as an alpha-agonist to increase peripheral vascular resistance
• Ivabradine (5-7.5mg twice daily) in cases with predominant tachycardia before syncope (postural orthostatic tachycardia syndrome component) 1. It is essential to note that the use of nitroglycerin during the tilt table test may cause headache and potentially aggravate hypoxemia by increasing ventilation-perfusion mismatch, as reported in the guidelines for the early management of patients with acute myocardial infarction 1. However, the most recent and highest quality study, the 2017 ACC/AHA/HRS guideline for the evaluation and management of patients with syncope, provides recommendations for tilt-table testing, including the use of adjunctive agents like nitroglycerine to improve sensitivity, although with decreased specificity 1. The European Heart Journal guidelines for the diagnosis and management of syncope (version 2009) also provide recommendations for tilt testing, including the use of a fixed dose of 300-400 µg sublingually administered in the upright position for nitroglycerine 1. Overall, the management of a patient with a positive tilt table test with nitroglycerin and tachycardia should prioritize preventing the paradoxical vasodilation and/or bradycardia that occurs during vasovagal episodes, while also considering the potential risks and benefits of pharmacological therapy.

From the Research

Management of Positive Tilt Table Test with Nitroglycerin and Tachycardia

• The management of a patient with a positive tilt table test with nitroglycerin and tachycardia involves the use of various medications and therapies to prevent recurrent episodes of syncope.
• According to 2, midodrine hydrochloride may be an effective therapy in patients with recurrent neurocardiogenic syncope refractory to other forms of therapy.
• The use of fludrocortisone, as reported in 3, can also improve orthostatic tolerance in patients with severe orthostatic hypotension.
• In some cases, sleeping in a head-up-tilt position, as described in 3, can help improve orthostatic tolerance and reduce symptoms.
• The study in 4 suggests that midodrine hydrochloride or atropine can prevent tilt-induced hypotension and bradycardia in patients with vasovagal syncope.
• The use of head-upright tilt table testing, as evaluated in 5, can be a useful tool in the evaluation and management of syncope in children and adolescents.
• The administration of sublingual nitroglycerin during upright tilt testing, as assessed in 6, can help unmask the vasovagal origin of unexplained syncope in patients without organic heart disease.

Treatment Options

• Midodrine hydrochloride: may be effective in preventing recurrent episodes of neurocardiogenic syncope 2
• Fludrocortisone: can improve orthostatic tolerance in patients with severe orthostatic hypotension 3
• Head-up-tilt sleeping position: can help improve orthostatic tolerance and reduce symptoms 3
• Atropine: can prevent tilt-induced hypotension and bradycardia in patients with vasovagal syncope 4
• Beta blockers: may be used to prevent episodes of syncope, although they may not be effective in all patients 2, 5

Diagnostic Testing

• Head-upright tilt table testing: can be used to evaluate and manage syncope in children and adolescents 5
• Sublingual nitroglycerin administration during upright tilt testing: can help unmask the vasovagal origin of unexplained syncope in patients without organic heart disease 6