A method and apparatus for detecting abnormal wave train complex

摘要

1282051 Electro-medical apparatus J M M NEILSON 12 March 1970 [14 March 1969] 13659/69 Heading G1N E.C.G. signals are monitored by integrating successive segments of the QRS complex, determining the differences between the integrated valve of each successive segments of the complex and the integrated value of a corresponding segment of a normal QRS complex, and quantitatively summing the differences to provide an indication of a normal or foreign (abnormal) complex depending on whether the sum exceeds or is below pre-set thresholds. As shown, the E.C.G. signal is applied both to an operational section via a delay line, Fig.5 (not shown), and to a trigger section. In the trigger section, Figs. 6 and 7 (not shown), two sets of pulses are produced - master timing pulses having a fixed time relationship to the start of each QRS complex and master trigger pulses having a fixed time relationship to the middle of each QRS complex. These two sets of pulses are applied to a control section, Fig.8 (not shown), which provides control pulses for the operational section, Fig.9 (not shown). The first control pulses (integrate reference segment) is initiated, after an adjustible delay with respect to the master timing pulse, to cause the delayed E.C.G. signal to be integrated prior to the occurrence of a QRS complex, this providing a reference level. Successive integrate segment pulses are then initiated and these cause each segment of the incoming QRS complex to be integrated and compared with the integrate of valve of the corresponding segment of a normal complex which are stored in the operational section. A sum of the differences, upon initiation of a "decide" pulse, is compared with pre-set thresholds. If the total exceeds a threshold, a foreign complex is present. However, if a normal complex is present, a logic circuit, Fig.11 (not shown), provides a transfer pulse to up-date the stores in the operational section with the integrated values of the segments just processed. The master timing and trigger pulses are also applied to a timing section which gives an indication of early QRS complexes. The logic section can then provide indications of the different types of complexes as shown in Fig.4. Utilizing the shown indications various heart malfunctions may be indicated, e.g. ventricular ectopic complexes, ventricular fibrillation (extreme irregularity of shape of the complexes), ventricular tachycardia (sequence of early foreign complexes), atrial tachycardia (rate of normal complexes above certain level), atrial fibrillation. An inhibit section, Fig.10 (not shown), if provided to inhibit operation when excessive background interference is present.