Circle Safe
Reinventing Phrenic Nerve Monitoring for Patient Safety

At Circle Safe, we’re committed to enhancing patient safety during atrial fibrillation (AF) ablation procedures by introducing cutting-edge solutions for phrenic nerve monitoring. Our technology is designed to streamline current practices, providing faster and more reliable nerve damage detection to reduce patient risks.
The Challenge:
Complex and Unstandardized Monitoring
- Delayed nerve damage detection.
- Subjectivity in observing diaphragm movement.
- Variability in how operators interpret results.
- Lack of standardization in stimulation thresholds and parameters.
These obstacles compromise procedure reliability and elevate patient risk.
Circle Safe’s Solution:
Real-Time, Accurate Monitoring
Circle Safe addresses these challenges with a solution that offers precise and reliable real-time monitoring:
CircleCath®

A high-precision catheter that stimulates the phrenic nerve while simultaneously recording diaphragmatic CMAP. This enables immediate nerve damage detection, reducing risks to patients.
D-Safe®

D-Safe®, A real-time monitor that tracks CMAP progression, alerting physicians instantly when a threat is detected, enabling quick, targeted intervention.
Our Goal:
Prevent Diaphragmatic Paralysis and Set a New Standard
We are committed to making phrenic nerve monitoring more effective, helping operators prevent diaphragmatic paralysis during “one-shot” AF ablation procedures. Our solutions enhance patient safety while providing real-time support for physicians.
A Promising Future with Strategic Funding
To accelerate development and bring our solutions to market, Circle Safe has raised €8 million.
This funding will help us finalize our FDA and CE certifications and launch in the U.S. by the end of 2025, with plans for a European launch in mid-2026. We’re focused on reinventing diaphragmatic monitoring and setting a new standard in the field, while driving sustainable growth and expanding access for healthcare professionals and their patients.