Managing Heart Failure: Wireless Antenna for a Monitor Implanted in the Pulmonary Artery

Heart failure management is increasingly moving toward continuous, real-time physiological monitoring. For patients with advanced heart failure, small shifts in pulmonary artery hemodynamics can signal impending decompensation days before symptoms appear.

Neva Electromagnetics was brought in to solve a critical challenge:

Design and validate a wireless antenna for a sensor implanted in the pulmonary artery capable of transmitting viscosity and blood flow velocity data reliably through human tissue to an external monitor.

https://video.wixstatic.com/video/c0caa9_3cfff737589e4714a1def1d7e9a508a5/720p/mp4/file.mp4

The Challenge

The sensor is positioned within the pulmonary artery, deep inside the thoracic cavity. The device needed to:

• Operate within strict size constraints

• Transmit through highly lossy biological tissue

• Meet regulatory safety requirements

Unlike external wearables, implantable antennas must operate within a conducting, high-dielectric medium. Human tissue drastically attenuates RF signals, especially in the thoracic region where lung tissue, blood, bone, and cardiac motion introduce variability.

Engineering Constraints

• Tissue Attenuation and Signal Loss

Biological tissue exhibits:

• High permittivity

• Significant conductivity

• Frequency-dependent absorption

  
  

These properties detune traditional antenna geometries, reduce radiation efficiency, and distort radiation pattern. The antenna had to be designed specifically for operation inside blood and surrounding thoracic tissue.

• Extreme Size Limitations

The implant geometry constrained antenna dimensions to millimeter-scale.

Miniaturization typically reduces efficiency and bandwidth, requiring:

• Careful impedance matching

• Custom geometry optimization

• Frequency tuning for in-body operation

Neva EM Virtual Human Body Models

Using the validated Neva EM VHP Female 5.0 model, we simulated the antenna in a realistic body environment including the pulmonary artery and all surrounding tissues all the way through the skin.

Designing the Optimal Antenna

The realistic VHP Female 5.0 computational environment allowed us to:

• Optimize antenna geometry

• Evaluate radiation patterns, radiation efficiency, and detuning effects

• Discover best positions for on-skin receiving antennas

By analyzing this data, we identified an optimal receiver zone that maximized:

• Signal reliability

• Power efficiency

• Transmission stability across body types

  
  

This allowed the customer to design a receiver that ensured consistent performance.

Supporting the Next Generation of Implantable Monitoring Devices

As cardiovascular and chronic disease management moves toward continuous implantable sensing, electromagnetic performance inside the body becomes a primary design constraint — not an afterthought.

Neva EM partners with medical device innovators to design:

• Implantable antennas

• Wireless power transfer systems

• In-body communication systems

• Human tissue RF modeling frameworks

If your team is developing an implantable or in-body wireless device, early electromagnetic modeling can dramatically reduce development risk.

Contact us to schedule a technical consultation to evaluate your in-body RF design challenges.

Model used in this simulation:

VHP Female 5.0

Access the Model