Navigating recurrent syncope evaluation in practice

Understanding the cause of recurrent syncope can be a puzzling and high-stakes challenge. While some episodes may be benign, others could signal serious cardiovascular, neurologic, or metabolic conditions that require timely evaluation. Clinicians must carefully weigh patient history, symptom triggers, medication effects, and physical exam findings to identify the underlying cause.

Determining the right combination of diagnostic tests, ranging from cardiac monitoring to tilt-table assessments, is critical to preventing future events and guiding effective management.

How do you distinguish between vasovagal episodes, arrhythmias, orthostatic changes, and other potential causes? Log in or sign up to share your approach and see the Consensus.

Questions for consult 

 Comments

Key takeaways about recurrent syncope evaluation:  

• Focus on history, exam, and meds
  Clinicians recommend looking for triggers, prodrome, orthostatic changes, and medication effects. Stopping a potential culprit like thiazides can help identify the cause.
  
• Start with key diagnostic tests
  Consider ordering an  EKG, echocardiogram, and Holter or extended cardiac event monitoring. If cardiac workup is unrevealing, pursue tilt-table testing, EEG, or brain MRI to evaluate autonomic or neurologic causes.
  
• Tailor follow-up and management
  Adjust medications, monitor symptoms, and escalate testing based on recurrence. Some clinicians recommend considering underlying conditions like POTS, hyponatremia, or other reversible factors before moving to more invasive diagnostics.
  

Cardiology

"1. Her syncope sounds vasovagal, especially given her brief prodrome and positive orthostatic vital signs. I would stop the thiazide diuretic.

2. Extended cardiac event monitoring or an implantable loop recorder can be helpful at evaluating for arrhythmia, and an echocardiogram could be performed to exclude structural heart disease. If this workup is unrevealing, I would consider an EEG and MRI brain."

Family Practice

"1. She needs a full cardiac evaluation with echo and Holter to rule out cardiac etiology. Once this has been performed and is normal, then I would do tilt testing to establish a diagnosis of autonomic dysfunction.

2. Tilt testing would help establish autonomic dysfunction, which seems to be much more common in the last decade than in my first decade practicing medicine."

Family Practice

"1. Consider things like orthostatic hypotension, hyponatremia, vasovagal syncope, arrhythmias, and possibly neurologic causes.

2. I would dive deeper into the history. Maybe there is a cause that has not yet been discovered, like a new supplement or a change in lifestyle. EKG, CMP, CBC, echo, tilt table, and possibly neuroimaging if persist."

Internal Medicine

"1. Thorough history and physical exam seemingly reveal a few differential possible causes, including hyponatremia (unlikely if mild) as well as orthostasis. Patient needs further workup, but differential includes medication side effect, cardiac etiology, versus something more autonomic like POTS.

2. Start simple and change HCTZ to another drug class. Patient should also have a Holter monitor and tilt table test."

Cardiology

"1. Cardiologist vs neurological…considering orthostasis and history of occurring while standing would first stop the diuretic. Follow BP and see if syncope recurs.

2. Could do an echo and EKG. If recurrent when off the diuretic, consider a tilt and event monitor."

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