A software trigger for intracardiac waveform detection with automatic threshold adjustment

A system has been designed for online multichannel analysis of intracardiac signals. The system performs automatic waveform detection and interval measurement during cardiac electrophysiologic studies. The system can detect atrial depolarizations (A) on the high right atrial channel (HRA), His bundle depolarizations (H) on the His bundle electrogram (HBE), and ventricular depolarizations (V) on the signal from the right ventricular apex (RVA). In addition, the waveform recognition algorithm recognizes and ignores pacing artifacts. Capture or noncapture is reported during pacing protocols, and the A-A, A-H, H-V, and V-V intervals are presented in real time. The triggering algorithm has been shown to perform extremely well in event detection. The algorithm has a very low false positive and false negative rate (0.3% and 0.8%, respectively). In cases of correct waveform recognition the algorithm measured 95.5% of the intervals to within 10 ms.<>