Rhythm classification by correlation-waveform morphology analysis of atrial and ventricular electrogram signals

Area of Science:

• Cardiology
• Electrophysiology
• Medical Instrumentation

Background:

• Distinguishing between ventricular tachycardia (VT) and supraventricular tachycardia (SVT) is critical for appropriate patient management.
• Traditional methods for tachycardia discrimination can be challenging, necessitating improved diagnostic tools.
• Electrogram (EGM) analysis offers a potential avenue for differentiating these arrhythmias.

Purpose of the Study:

• To evaluate the efficacy of correlation-waveform analysis (CWA) using atrial and ventricular electrograms (EGMs) for distinguishing VT from SVT.
• To compare the diagnostic performance of CWA in the atria versus the ventricles.

Main Methods:

• Twenty-two patients undergoing electrophysiologic testing with induced tachycardias were studied.
• Correlation-waveform analysis (CWA) was performed on atrial and ventricular EGMs.
• Recorded EGMs during tachycardias were compared to sinus rhythm or paced rhythm templates, generating a CWA percent-match (CPM) score.

Main Results:

• Using a sinus rhythm template, atrial CPM scores were significantly higher for VT (93%±5%) than for SVT (66%±20%) (P=0.0034).
• An atrial CPM cutoff of 85% yielded 100% sensitivity for VT and 80% specificity for SVT rejection.
• Ventricular CWA showed less discrimination between SVT and VT compared to atrial CWA.

Conclusions:

• Atrial correlation-waveform analysis (CWA) is a superior method for discriminating between ventricular tachycardia (VT) and supraventricular tachycardia (SVT) compared to ventricular CWA.
• The findings suggest that CWA of atrial electrograms can reliably differentiate between these two common tachycardia types.
• Combined atrial and ventricular CWA may offer even greater diagnostic accuracy.