The Frog Sign: A Key Clue for Diagnosis
During an AVNRT episode, you might notice rapid, visible pulsations in your neck, similar to the throbbing of a frog’s throat - hence the name "frog sign."
In AVNRT, the upper and lower chambers of your heart contract at almost the same time.
Because the valve between these chambers is closed during this contraction, blood is pushed backward into the veins in your neck, creating the visible pulsations.
Not everyone notices the neck pulsation and many more notice a very strong heartbeat, making their whole body shake in time with their heart.
AVNRT
Understanding Atrioventricular Nodal Reentry Tachycardia
Atrioventricular nodal reentry tachycardia, or AVNRT, is a condition that causes your heart to beat much faster than normal. This happens because of a short circuit in the heart’s electrical system, specifically near the AV node - the natural electrical bridge between the upper and lower chambers of your heart. When this short circuit occurs, it creates a loop of electrical signals, leading to a rapid and regular heartbeat.
Who is Affected by AVNRT?
Age:
AVNRT is most often diagnosed in young adults, usually between the ages of 20 and 40.
It can occur in children and older adults, but it’s less common in these age groups.
Gender:
Women are twice as likely to experience AVNRT compared to men.
How Common is AVNRT?
AVNRT is the most common type of supraventricular tachycardia (SVT), accounting for about 60% of cases.
It affects roughly 23 out of every 100,000 people each year.
What Happens if AVNRT is Left Untreated?
Symptoms: You might feel your heart racing, experience dizziness, shortness of breath, or chest discomfort. Some people may even faint during an episode.
Impact on Life: While AVNRT is rarely dangerous, frequent episodes can be unsettling and may limit your daily activities.
Long-term Effects: In rare cases, if the fast heart rate continues for a long time, it can lead to more serious heart problems.
Catheter Ablation for AVNRT
Catheter ablation is a highly effective treatment for AVNRT, with a success rate of over 95%.
What Does the Procedure Involve?
A thin, flexible tube called a catheter is inserted into a vein (usually in your groin) and guided to your heart.
The catheter records your heart’s electrical activity to pinpoint the area causing the abnormal rhythm.
Once identified, a small amount of energy (either heat or cold) is used to destroy the problematic tissue, stopping the short circuit.
Types of Ablation:
Slow Pathway Ablation: This is the most common method and targets the part of the AV node responsible for the short circuit.
Fast Pathway Ablation: This is used less often because it carries a slightly higher risk of damaging the heart’s natural pacing system.
Is It Safe?
Catheter ablation is generally very safe, with most people experiencing no further episodes of AVNRT afterward.
As with any procedure, there are some risks, such as a small chance of needing a pacemaker or the arrhythmia returning.
X-ray-free procedures with 3D Mapping
Modern technology has made catheter ablation even safer and more precise.
Zero Fluoroscopy:
This approach uses advanced 3D mapping systems to guide the catheter without relying on X-rays, reducing radiation exposure.
3D Mapping Systems:
These systems create a detailed, real-time 3D map of your heart, helping doctors navigate the catheter with precision.
Benefits include greater accuracy, shorter procedure times, and improved safety for both patients and medical staff.
Final Thoughts
AVNRT is a manageable condition, and catheter ablation offers a highly effective solution. With advancements like zero fluoroscopy and 3D mapping, the procedure is safer and more precise than ever. If you experience symptoms like a racing heart or dizziness, it’s important to see a heart specialist for an evaluation. Early diagnosis and treatment can help you return to a normal, active life.