Overview:
At 24, a Maryland PhD student considered herself healthy and active. But when she began experiencing unexplained dizziness while seated or waking up, she never imagined it could be her heart.
The Journey:
After months of symptoms, she visited her primary care physician. Initial bloodwork was normal, and she and her physician agreed that she would wear a Zio patch – a heart monitor device that would track the rhythm of her heart over a two-week period. She expected it to rule out any cardiac issues.
Instead, the results revealed a third-degree heart block, a serious condition where the electrical signals that control your heartbeat are completely interrupted. She was advised to go immediately to the emergency department at Union Memorial Hospital, where she was admitted for observation.
The Diagnosis:
Tests confirmed the heart block and a diagnosis of vasovagal syncope – a condition that causes fainting due to sudden drops in heart rate and blood pressure. Traditionally, this would mean a pacemaker, especially given the severity of her block.
An Alternative Approach:
Sunjeet Sidhu, MD, a cardiac electrophysiologist practicing at MedStar Union Memorial Hospital and MedStar Franklin Square Medical Center, consulted with Apostolos Tsimploulis, MD, Associate Director of Complex Arrhythmias and Innovations Program for MedStar Heart & Vascular Institute. Dr. Tsimploulis had begun using a procedure called cardioneuroablation (CNA) for vasovagal syncope – an approach that is gaining traction as a promising alternative, especially for younger patients.
CNA uses targeted ablation to reset the heart’s electrical signals, potentially avoiding the need for a pacemaker. For younger individuals, this could mean fewer complications and a more natural recovery.
This approach is supported by findings from the largest U.S. registry on CNA, published in JACC: Clinical Electrophysiology. In a study of 205 patients across 15 centers, CNA led to a significant reduction in fainting episodes and helped 97% of patients avoid pacemaker implantation altogether.
The Outcome:
The patient underwent CNA at MedStar Washington Hospital Center in July 2025. After a week in the hospital and a few weeks of recovery, she returned to her PhD rotation. Two months later, she reports no recurring symptoms, and a loop recorder shows normal heart activity.
Why It Matters:
This case highlights a promising alternative for young patients facing pacemaker implantation due to vasovagal syncope. While CNA isn’t yet the standard, growing evidence – including multicenter registry data – suggests it may soon become a widely accepted option for select patients.
If you or someone you know experiences unexplained fainting or dizziness, talk to your doctor about emerging options like CNA.