Ajay Neginhal

This capstone project focused on building a closed-loop cardiac electrogram acquisition and pacing system. The device distinguishes between normal sinus rhythm and patterns requiring intervention, then adapts pacing frequency to restore a healthy rhythm.

AcademicJan 2025 - May 2025Capstone Design Team

Implantable Cardiac Electrogram and Pacemaker

Implantable electrogram acquisition and pacing system that detects arrhythmia patterns and drives corrective pacing.

Figure coming soon
Signal chain and pacing control overview (placeholder).
BiomedicalAnalogEmbeddedSignal ProcessingPacemaker

Key Reminders

  • Walk through the electrogram signal chain and how noise was handled.
  • Explain the pacing control logic that returns the heart to sinus rhythm.
  • Highlight the use of LTSpice and bench emulation to validate behavior.

Technologies

LTSpiceAnalog FiltersOp-AmpsMicrocontrollerPulse ModulationPressure SensorsFunction Generator

Clinical Problem

Designed a device capable of distinguishing healthy sinus rhythm from dangerous rhythms that require pacing intervention. The system continuously senses an electrogram, evaluates rhythm state, and applies corrective pacing when needed.

System Architecture

The architecture includes an analog front end, rhythm classifier, and a pacing signal generator. Bench emulation used a multi-wave function generator and pulse modulation to simulate physiologic signals.

Figure coming soon
Electrogram acquisition and pacing architecture diagram placeholder.

c code

Code example forthcoming

Pacing control state machine.

Analog Front End

Developed amplification and filtering stages to isolate the electrogram from noise while preserving clinically relevant features for rhythm classification.

Figure coming soon
Analog front-end schematic placeholder.

Testing and Validation

Validated sensing, classification, and pacing behavior using simulated rhythms in LTSpice and on the bench.

Figure coming soon
Electrogram and pacing response plots placeholder.

Demo and Next Steps

Future work includes encapsulation, biocompatibility planning, and power optimization for implantable deployment.

Figure coming soon
Demo video placeholder.