10- Pacemakers

Question 1

What is the role of the pacemaker ?

Answer 1

Supports the heart and circulatory system

Question 2

Site the date of the fort portable pacemaker and it’s évolution till nowadays

Answer 2

1958: first portable pacemaker
2004: implantable pacemaker

Question 3

Site the typical system components for pacemakers

Answer 3

Leads/electrodes
Pacemaker device
External computer for programming

Question 4

Site the main part of the circuitry of a pacemaker

Answer 4

impulse generator
electrode for stimulation
return electrode
heart (tissue resistance)

Question 5

which part of the circuitry generate the pulse ?

Answer 5

The capacitor.

Question 6

how to create a pulse

Answer 6

generate a stimulation
delay
bring capacitor in
discharge the capacitor

Question 7

what are the aims of the circuit of a parcemaker ?

Answer 7

create a biphasic pulse

charge accumulation ensures proper charge compensation

Question 8

what are the key parameters

Answer 8

electrodes size 
ranges of impedance
tissue resistance (loss voltages)

Question 9

what are the five main parameers of pacemaker code in the right order ?

Answer 9

chamber paced (A,V,D) - chamber sensed (A,V,D) - response to sensing (I,T,D) - programmability rate to modulation (P, M, C, R) - antiarrhythmia function (P,S,D)

Question 10

How to hermeticaly seal pacemakers ?

Answer 10

titanium and electril feedthrough

Question 11

how are pin connectors in pacemaker ?

Answer 11

made of plastic, connector with clamp.

Question 12

Cite the electronic components of pacemakers

Answer 12

Coil, battery(5-10y), electronics, IC packaging (ASICs, hybrid), subtrate (ceramic, FR4 captor)

Question 13

Cite the implant electronics components

Answer 13

pulse generator (capacitor), signal detection(ECG), signal processing (ecg analysis) and communication (coil)

Question 14

site advantage of unipolar field stimulation

Answer 14

simple concept, low space requirement

Question 15

Site advantage of bipolar field stimulation

Answer 15

less susceptible to interference, more complex to manufacture.

Question 16

Describe the implantation of pacemaker

Answer 16

leads: transvenous, fena subelavia dextra (if right ventricle via vena cava if left, in right atrum via coronary artery).
stimulator in skin/muscle.

Question 17

Site two example of wireless pacemakers

Answer 17

Nanostim(st jude medical) or micra(medtronic)

Question 18

Defines the three pacing and sensory functions

Answer 18

Fixed frequency (stimulator in right ventricle)
P wave triggered ( sensed in A , paced in V)
R wave controlled (paced and sensed in V)

Question 19

When is done atrial stimulation ?

Answer 19

1 before Pwave

Question 20

cite 3 pacemakers mode

Answer 20

A sensing, V pacing
V sensing, A pacing
A and V pacing (before P, and anorther time)

Question 21

which parameter can be chosen for the stimulation ?

Answer 21

impulse amplitude and duration, sensitivity, interval for trigger (time between detected heart signal and stimulation) and conduction (time between stimulation and activation)

Question 22

how are sensors integratted in pacemakers ?

Answer 22

receive from heart and disturbance inf, send to pacemaker.

Question 23

what is the sick sine syndrom (SSS) ?

Answer 23

Information for frequency is missing.

Question 24

What are the limit for control in pacemaker ?

Answer 24

Open loop control and no inf about hemodynamic needs.

Question 25

what amount of energy has to be given for defibrillator ?

Answer 25

3 J:Kg. so from 200 to 400J at 2A for 10-20

Question 26

what is called AED ?

Answer 26

Automated External Defibrillator (def. after ECG measurement)

Question 27

how does defibrillators works ?

Answer 27

defibrillation of the atria - triggering from R wave.

Question 28

what are the main actors in circuit for defibrillation.

Answer 28

capacitor to discharge

coil to smooth peaks

Question 29

How does the semi automated defibrilator works ?

Answer 29

USer delivers the discharge