Factors that drive the expansion of the pacemaker number include rising cardiovascular diseases, technical advancement, and upturning living standards. There are substantiated statistics that over 1 million devices were implanted in 2016 [1] . Correspondingly, the requirement of pacemaker detection also increased as the prevalence.
Intelligence, functionality, and longevity have always been the aims of manufacturers. Modern pacemakers are able to realize multiple pacing modes. Moreover, to feed the demand for product longevity, both pulse width and pulse amplitude have been descended from 1 ms to 0.09 ms, and 5V to 0.13V, respectively.
However, it brings a challenge for an ECG machine to detect such a subtle signal. The wrong diagnosis could lead to dizziness, fainting or loss of consciousness, palpitations, and some other severe conditions [2].
The pacing signal could be deduced through the spikes in ECG, while narrow width hinders spike detection, especially in the presence of distracting electrical noise.
The 80 kHz sampling rate allows SE-1202 to capture ECG signal with a 12.5-μs interval between two adjacent sample points. In the same word, it practices 40 sample points to depict a typical 0.5 ms pacing stimulus. Then, there will be a sufficient number of points to plot the fast-rising and falling edges of pacer pulses, guaranteeing every stimulus will be recorded precisely by the pattern recognition techniques.
Fig. 1 An example of pacer pulse detection at an 80 kHz sampling rate.
A high sampling rate allows SE-1202 plots to rise fast and falling edges of pulse with enough points
Since the pacing capture threshold varies in different individuals and pacing chambers, the pacing pulse amplitudes present a distinct shift at the body surface. With limited sensitivity, the spikes would be overlooked. Therefore, high-sensitive performance is desired in ECG to detect the minimum changes of voltage.
Fig. 2 An example of various amplitudes difference pacing chambers.
Without a high-sensitive ECG, such low amplitude pulses could never be detected, like atrial pulse and the 2nd ventricular pulse
Pacing modes are required to be tailored for diverse patients. The SEMIP® algorithm enables the recognition of more than a dozen pacing modes, and the enhanced accuracy of diagnosis reduces the likelihood of inappropriate clinical decisions.
The ordinary ECG overlapping the pacing peaks on the waveforms, which makes them hard to identify. An individual pacemaker display channel is available in SE-1202, to provide the cardiologists an intuitive visualization of stimulating peaks and simplify the analysis of the pacemaker.
Fig 3. Individual pacemaker display channel
Reference
[1] https://www.statista.com/statistics/800794/pacemakers-market-volume-in-units-worldwide/
[2] https://www.fairview.org/patient-education/116363EN
