Computer diagnosis of the heart - pacemaker interface

The object of the so-called Electrocardiographic Inverse Problem is the algorithmic analysis and diagnosis of the electrocardiogram (ECG). A part of this general problem is the Pacemaker Inverse Problem, which means the analysis of the ECG in order to establish details of heart-pacemaker interaction (HPI) with special reference to the diagnosis of pacemaker failure. The solution to this problem is of practical importance, because it is often impossible to evaluate such records clinically. The ECG patterns of natural cardiac activity and of the events stimulated by the pacemaker may not be distinguishable and many combinations of potential response of the implanted device have to be taken into account. A computer system providing automatic analysis of the HPI, based on ECG data, has been developed and implemented on an IBM PC AT computer. The system uses a complex algorithm which enables the evaluation of all possible combinations of HPI events, and establishes for each of these combinations its correspondence to the specified pacemaker algorithm. The system is written in Turbo Pascal and its source text has more than 11 000 lines.