Product Manual

Patient Monitor User Manual Monitoring ECG
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arrhythmia analysis. If the ECG signal is too small, a false asystole alarm may occur.
Aberrantly-Conducted Beats:
As not recognizing the P waves, the monitoring system is difficult to distinguish between
aberrantly-conducted beats and ventricular heartbeat. If the aberrantly-conducted beat is similar
to ventricular tachycardia, it may be classified as ventricular. Make sure to select such a lead, the
aberrantly-conducted beats have an R wave that is as narrow as possible to minimize the incorrect
calls. The ventricular should have a different appearance from “normal heartbeat”. Physicians
should be more alert to these patients.
Intermittent bundle branch block: bundle branch block or other bundle obstruction phenomenon
is a challenge for arrhythmia algorithm. If the QRS wave during the block has a considerable
change in morphology compared to the normal QRS of learning, the blocked heartbeat may be
misclassified as ventricular tachycardia, resulting in an incorrect chamber alarm. Make sure to
select such a lead, which blocks the heartbeat of the R wave as narrow as possible to minimize
the wrong classification. Ventricular heartbeat should have a different appearance from “normal
heartbeat”. Physicians should be more alert to these patients.
NOTE:
1 Arrhythmia analysis is intended to be used with MFM-CMS 2.65 or above version.
Please update MFM-CMS if its version is lower than 2.65.
2 Heart rate reading may be affected by cardiac arrhythmias. Do not rely entirely on
heart rate alarms when monitoring patients with arrhythmia. Always keep these
patients under close surveillance.
3 Since the arrhythmia detection algorithm sensitivity and specificity is less than 100%,
sometimes there may be some false arrhythmias detected and also some true
arrhythmia events may not be detected. This is especially true when the signal is
noisy.
4 The ventricular HR mentioned above refers to: when the consecutive PVCs number ≥
3, the algorithm calculates ventricular HR with the average of 2-8 RR intervals. The
methods are different from the HR Averaging Method of the monitor. Therefore, the
ventricular HR values calculated by algorithm may be different from the HR values
calculated by HR Averaging Method. The ventricular HR is for judging arrhythmias
and is not exactly equal to the HR displayed on the interface.
5 The ARR analysis results and HR values obtained during ARR analysis and HR
calculation are not affected by the selected filter mode. The algorithm itself has
independent data-flow processing, which can better ensure the consistent and
accurate results in different filter modes.
6 Atrial fibrillation alarm should meet below two conditions for 1 minute:

The RR interval of normal beats must be irregular,

It can be seen that the obvious f or P waves do not exist.
7 Atrial fibrillation analysis is only applicable to adult patients and should not be
performed for PVC or pacing fluctuations.
8 Atrial flutter cannot be detected by the atrial fibrillation algorithm because most of
their RR intervals are regular.
9 In following situations, atrial fibrillation alarm detection error may occur: