Cardiac Tissue is (-) at rest and (+) at contraction
0 - Na channels are open
1 - K channels open and start repolarization
2 - Ca channels open and delay repolarization
3 - Ca channels close
4 - Rest
Cardiac cells are ______________ charged at rest - Answers-Negatively
Components of DFT and DBS conductors - Answers-Silver and MP35N
Best type of capacitor - Answers-Tantalum Electrolytic
Describe the depletion Lithium Silver Vanadium Oxide battery - Answers-Predictable, 3
plateaus in discharge curve
,Common battery type for ppm? ICD? - Answers-Ppm - Lithium Iodide
ICD - Lithium Silver vanadium oxide
1 Hz = ___________ bpm - Answers-60
100 bpm = _________ Hz - Answers-1.67
Battery components:
Capacitor -
Reed Switch -
Diode -
Resistor -
Rectifier - - Answers-Cap - stores electrical charge
Reed - switches ppm to Magnet mode
Diode - ensures one way flow of current
Resistor - restricts current flow
rectifier - creates all pos or all neg signals
Voltage of PPM battery? - Answers-2.8V
Voltage of ICD battery? - Answers-3.2V
Types of Sensors: Open Loop - Answers-Only takes in positive feedback; ex:
piezoelectric sensor senses movement -> increased rate until no more sensed
movement
Types of sensor: closed loop - Answers-More physiologic than open loop; rate changes
in response to physiologic change -> rate stays until physiologic state indicates it needs
to slow (ex: 02 sats)
Types of Sensors: Primary - Answers-Detects changes that normal effect the sinus
node (02 sats, myocardial contractilty)
Types of sensors: Secondary - Answers-Detects internal changes that result from
exercise
Types of sensors: Tertiary - Answers-Detects external changes as a result of exercise
(piezoelectric, accelerometer)
Describe acute threshold graph of steroid eluting lead VS polished platinum post implat
- Answers-Steroid: low threshold and not much change
polished platinum: bad. High threshold, acute rise, then chronic high threshold
What creates a higher current density? - Answers-Smaller pacing cathode
Anode must be atleast _____ times _______ than cathode - Answers-3x Larger
, ohms law - Answers-V=IR
Most common electrolyte abnormality to cause LOC? - Answers-Hyperkalemia
Effects of Hyperkalemia - Answers-Increase in threshold, wide paced complex, latency,
peaked T wave
Effects of Hypokalemia - Answers-Irratble foci, R on T, Torsades
Equation for current drain - Answers-Time = Battery capacity / current drain
Time = AmpHour/amperes = Hours
Micro units - Answers-10^-6
BOL
ERI
EOS - Answers-Beginning of Life
Elective Replacement Indicator
End of Service
Cardiac cell charge and electrolyte membrane potential at rest - Answers-Charge: ~(-
90mV) inside of cell
Membrane: Na+ outside;
Preferred Peak to Peak for P and R waves - Answers-P waves: >2mV
R waves: >5mV
Preferred slew rate for P and R waves - Answers-P waves: > .5 V/s
R waves: > .75V/s
Co- Axial VS Co-radial conductor types - Answers-Co - Axial: One conductor coil inside
the other
Co - radial: Two coils overlayed around the radius of lead
S1
S2 - Answers-S1: Drive train
S2: First premature impulse
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller GEEKA. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $10.99. You're not tied to anything after your purchase.