Instruction Manual

14
Special Functions
Screening for atrial fibrillation during blood pressure measurement
The device is designed to screen for atrial fibrillation during blood pressure
measurements (optional) with high accuracy: a sensitivity of 98% and a specificity value
of 92%*. If atrial fibrillation is detected this will be shown in the report.
Central blood pressure parameters
The device is designed to assess central blood pressure parameters (optional).
Central blood pressure is the pressure in the ascending aorta, the largest artery that
originates from the left ventricular of the heart and from where oxygen is distributed to all
parts of the body through the systemic circulation. Central Systolic Blood Pressure and
Central Pulse Pressure provided by this monitor are determined directly through pulse
volume plethysmography (PVP) waveform analysis. Central Diastolic Blood Pressure by
this monitor is calculated by subtraction of Central Systolic Blood Pressure and Central
Pulse Pressure.
How is central blood pressure measured?
The device measures brachial systolic and diastolic blood pressure as usual. However,
where the cuff normally totally deflates after the blood pressure measurement, the cuff
now stops deflating at approximately 60 mmHg cuff pressure to keep a stable pressure
on the brachial artery for approximately 10 seconds which is needed to acquire brachial
pulse volume plethysmography (PVP) waveforms (pulse volume recording). During
these 10 seconds approximately 10 PVP waveforms are recorded from which one
average PVP waveform is determined and analyzed. From the average PVP waveform,
some characteristic points (parameters) are identified that are directly related to arterial
compliance (stiffness) and wave reflections. With these parameters and previously
measured peripheral (regular) blood pressure the central systolic blood pressure value
and the central pulse pressure value are then determined
1
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About Atrial Fibrillation
Atrial fibrillation is a common heart rhythm problem and a common cause of major
strokes. It affects 8% of those 65 years and older and about 20% of all strokes are
caused by atrial fibrillation. Atrial fibrillation is a rhythm problem that can last from a few
minutes, to days or weeks and even years. Atrial fibrillation can lead to the formation of
blood clots in the heart. These clots can break off and flow to the brain causing stroke.
One sign of atrial fibrillation is palpitations. However, many people have no symptoms
and therefore may remain undetected whereas diagnosing atrial fibrillation early followed
by adequate treatment can largely reduce the chance of getting a stroke.
F
Verberk et al. Screening for atrial brillation with automated blood pressure measurement: Research evidence and
practice recommendations. Int J Cardiol 2016: 465–473.