Heart Rhythm Analysis

By: Shayan Riyaz

Motivation:

The purpose of this project is to explore Heart Rhythms using:

1. Signal Processing Techniques
2. Machine/Deep Learning
3. Causal Analysis/Inference

Dataset

Currently I am using ~450 subject MIMIC III subject via physionet. I converted Peter Charlton's collate_mimic_perform_af_dataset script for extracting the data from Matlab to python. (Using a mix of LLMs and my own intuiton). Next I used the MSPTDfast peak detection algorithm (again by Peter Charlton & again converted using LLM and my own understanding of the algorithm.).

Datasets Prepared:

• Training and Validation

  • (MIMIC III - Waveform)[https://physionet.org/files/mimic3wdb/1.0/matched/]
  • (MIMIC IV - Waveform)[https://physionet.org/files/mimic4wdb/0.1.0/]
    • (MIMIC IV ECG - Matched)[https://physionet.org/files/mimic-iv-ecg/1.0/] Mainly notes to classify subject diseases

• Testing

  • CapnoBase

Model Development

• Currently i created a dummy Conv1D net for peak detection for PPG Signals. (not sure if its necessary but a good learnign exercise).

Result Version 1 - Conv1d Net

Result Version 2 - Denoiser and Peak Extractor

Goals:

• Noisy Frame Detection using Deep Learning + Simple Statistical Measurments
• Peak Detection using Semi-supervised (pre-labeled using MSPTDfast algorithm) + Reinforcement learning based on physiological behaviour of pleth.
• Calculation of Features such as:
  • Time-domain: HRV (Heart Rate Variability), mean HR, PTT (Pulse Transit Time)
  • Morphological: Pulse amplitude, rising time, dicrotic notch position
  • ? (Still Studying)
• Some Type of Causal Modeling Architecture (X features, treatment) → outcome using TarNet
• Purpose of Causal Modeling: Predicting patient deterioration, alarm risk, personalization

References

• Charlton, P. H., Prada, E. J. A., Mant, J., & Kyriacou, P. A. (2025). The MSPTDfast photoplethysmography beat detection algorithm: design, benchmarking, and open-source distribution. Physiological Measurement. https://doi.org/10.1088/1361-6579/adb89e
• Charlton, P. H. (n.d.). PPG-Beats. https://ppg-beats.readthedocs.io/en/latest/ AF Annotations
• https://figshare.com/articles/dataset/Atrial_Fibrillation_annotations_of_electrocardiogram_from_MIMIC_III_matched_subset/12149091/1

Dataset Reference:

• Moody, B., Hao, S., Gow, B., Pollard, T., Zong, W., & Mark, R. (2022). MIMIC-IV Waveform Database (version 0.1.0). PhysioNet. https://doi.org/10.13026/a2mw-f949.