Vitatron T20 SR

Programming Parameters

Pacing and Sensing Parameters

Parameter Name Range Delivery Settings Per Model
Vitatron T20 SR
Lower rate 40-(5)-130 min-1 60 min-1
Maximum pacing rate 90-(5)-170 min-1 120 min-1
Pulse amplitudea 0.5-(0.25)-4.0-(0.5)-8.0 V 3.75 V
Pulse duration 0.1-(0.05)-1.0 ms 0.4 ms
Atrial sensitivity Uni: 0.5-(0.1)-1.0-(0.5)-7.5 mV
Bi: 0.25, 0.3-(0.1)-1.0-(0.5)-7.5 mV
0.7 mV
Ventricular sensitivity 1.0-(0.5)-10.0 mV 2.0 mV
Sensing/pacing polaritya Unipolar, Bipolar Unipolar
Refractory period 250-(10)-500 ms 330 ms
Conditional hysteresisa 0-(5)-30 min-1 0 min-1

a Conditional hysteresis is only applicable in VVI, VVT, AAI and AAT modes.

Other Programmable Parameters

Parameter Name Range Delivery Settings Per Model
Vitatron T20 SR
Flywheel On, Off Off
Night lower rate 40-(5)-130 min-1 60 min-1
Start of night 18:00-(5 min)-02:55 hh:mm 00:00
End of night 04:00-(5 min)-11:55 hh:mm 06:00
Pacemaker time 00:00-(1 min)-23:59 hh:mm 00:00
Sensor slope Auto, Fixed Auto
Activity threshold Low, Low/Med, Medium, Med/High, High Medium
Activity acceleration Fast, Standard, Gradual Standard
Activity deceleration Fast, Standard, Gradual Standard
Ventricular Rate Stabilization On, Off Off
Maximum therapy rate 70-(10)-120 min-1 100 min-1
Selected Episodes trigger Off, Atrial Rate (AAI(R) and AAT modes), Ventricular Rate (VVI(R) and VVT modes), Ventricular Variation (VVI(R) and VVT modes), Patient Assistant Off
EGM recording On, Off Off

Tolerances (valid between 22 °C and 45 °C throughout the pacemaker lifetime)

Parameter Tolerance
Lower rate (min-1) Programmed value ±15 ms
Maximum pacing rate (min-1) Programmed value ±15 ms
Pulse amplitude (V) Programmed value ≤ 1.0: +40%/-10%
Programmed value > 1.0 ≤ 4.0: +20%/-10%
Programmed value > 4.0 ≤ 7.0: +10%/-10%
Programmed value > 7.0: +10%/-20%
Pulse duration (ms) Programmed value - 0.02/+0.04
Atrial sensitivity (mV) Programmed value ±(10% +0.16) at 37 °Ca
Ventricular sensitivity (mV) Programmed value ±(20% +0.16) at 37 °Ca
Refractory period (ms) Programmed value ±15
Hysteresis (conditional) (min-1) Programmed value ±15
Lead impedance Measured value ±(20% +20 Ω)
Battery voltage Measured value ±0.03 V
EGM amplitude (atrial) ±(10% +0.16 mV) +1% of full scale (at 37 °Ca)
EGM amplitude (ventricular) ±(20% +0.16 mV) +1% of full scale (at 37 °Ca)
ECG marker timing ±10 ms

a Add ±10% over temperature range 22 °C to 45 °C.

Telemetered patient and pacemaker data (continued)

Data item
Patient’s name and identification code
Patient’s date of birth
Pacemaker type, model number and serial number
Pacemaker implantation date
Lead manufacturer, model number and serial number
Lead implantation date
Pacemaker dependent (yes/no)
Indications for pacing
Pacemaker time
Anticoagulation is applied (yes/no)
Anticoagulation start date
Physician’s name and phone number


Remaining pacemaker longevity
Remaining pacemaker longevity
Lead polarity
Lead impedance
Pulse amplitude
Battery status
Remaining battery capacity
Battery impedance
Battery voltage
Mean battery current
Consumed battery charge
Pulse energy
Average pulse current
P/R wave amplitude
Stimulation threshold
Fast learning

Diagnostic Capabilities

Category Feature
ECG and therapy analysis Intracardiac EGM
ECG event marker intervals
ECG marker annotation
Therapy Advisor
Holters 24 24-hour Holter
30-minute Holter
Histograms/tables Diurnal rhythm distribution
P-wave amplitude (AAI and AAIR modes)
Ventricular rate (VXX modes)
Ventricular rate irregularity (VXX modes)
Atrial rate (AAI, AAIR and AAT modes)
History Diagnostics
Counters Percentage of atrium or ventricle paced
Percentage of ventricle sensed (VXX modes)
Percentage of physiologic atrial senses (AAI, AAIR and AAT modes)
Percentage of pathologic atrial senses (AAI, AAIR and AAT modes)
Number of PACs (AAI, AAIR and AAT modes)
Number of accelerometer counts (AAIR and VVIR modes)
Selected Episodes Atrial Rate (AAI, AAIR and AAT modes) Ventricular Rate (VVI, VVIR and VVT modes) Ventricular Variation (VVI, VVIR and VVT modes) Patient Assistant

Technical parameters

Magnet mode

Parameter Rate
Magnet pacing mode AOO or VOO
Magnet rate, battery status "Good" 100 min-1 (600 ms)
Magnet rate, battery status "Ageing" 95 min-1 (630 ms)
Magnet rate, battery status "Replace PM" 86 min-1 (700 ms)

Warning: In magnet mode the pacemaker operates in an asynchronous pacing mode. If the intrinsic rate is higher than the magnet rate, this may induce ventricular tachycardia or ventricular fibrillation.

Exposed materials

Item Material
Can Titanium
Connector Polyether-Urethane (PUR) and silicone rubber

Physical characteristics

Chararacteristic Value
Dimensionsa 46.8 x 45.9 x 7.25 mm
Mass 27.3 ± 0.5 g
Volume 11.9 ± 0.5 cm3
Surface area 33.1 cm2
X-ray identification VF
Connector IS-1 single chamber

a Connector thickness may vary.

Electrical specifications

Chararacteristic Value
Output capacitor 3.4 μF
Input impedance ≥ 100 k Ω
Current/Energy consumption VVIR VVI
Pacinga 15.4 μA 14.8 μA
Inhibited 9.4 μA 8.9 μA

a 100% pacing at 60 min-1, 3.75 V, 0.4 ms, 500 Ω.

Power source

Chararacteristic Value
Cell type Pi 223 lithium iodine
Voltage 2.8 V (RRTa 2.6 V)
Capacity 1.4 Ah (RRTa 0.1 Ah)
Battery manufacturer MECC

a RRT = Recommended Replacement Time.

Interference and high rate protection

Parameter Value
Interference detection frequency 15.4 ± 0.5 Hz (923 ± 29 min-1)
Pacing mode during interference VOO(R) if programmed to a ventricular mode.
AOO(R) if programmed to an atrial mode.
OOO if programmed to the OOO mode.
Pacing rate during interference Pacemaker behaves as if no spontaneous cardiac activity
is present. If interference continues, the eventual pacing
rate is either the sensor-indicated rate or the lower rate,
whichever is the higher.
High rate protectiona 205 ± 10 min-1

a Atrial high rate protection for pacemakers programmed to AXX modes; ventricular high rate protection for pacemakers programmed to VXX modes.