Model-based interpretation of the ECG: a methodology for temporal and spatial reasoning

Abstract A new software architecture for automatic interpretation of the electrocardiographic rhythm is presented. Using the hypothesize-and-test paradigm, a semiquantitative physiological model and production rule-based knowledge are combined to reason about time- and space-varying characteristics or complex heart rhythms. A prototype system implementing the methodology accepts semiquantitative description of the onset and morphology of the P waves and QRS complexes that are observed in the body-surface electrocardiogram. A beat-by-beat explanation of the origin and consequences of each wave is produced. The output is in the standard cardiology laddergram. The current prototype generates the full differential diagnosis of narrow-complex tachycardia and correctly diagnoses complex rhythms, such as atrioventricular (AV) nodal reentrant tachycardia with either hidden or visible P waves and varying degrees of AV block.