Pacing and Programming Flashcards
What are the two basic components of a single chamber pacemaker?
Pacing
Sensing
What are the main components of sensing?
Amplitude
Slew rate
Amplitude
Peak to peak measurement or “height” of the sensed events
Slew rate
Change in voltage over change in time
What is the nominal amplitude of R waves?
> 5mV
What is the nominal amplitude for P waves?
> 2mV
What is the nominal slew rate for R waves?
> or equal to 0.75V/sec
What is the nominal slew rate for P wave?
> or equal to 0.50 V/sec
Over sensing leads to _____pacing and under sensing leads to ______pacing.
under pacing
over pacing
Fusion beat
A combination of an intrinsic beat and a paced beat
Pseudofusion beats
Pacing pulse falls on an intrinsic beat
The pacing pulse is ineffective and the intrinsic QRS complex is unchanged
Atrial escape interval (V-A interval)
Time in milliseconds from a ventricular paced/sensed event to the next atrial output pulse
Escape interval
The interval between the normal beat and the escape beat (or) time between a paced/sensed cardiac event and the next schedule pacing stimulus
Automatic interval
Pacing rate in milliseconds
Usually equal to the escape interval unless rate hysteresis is programmed on
What are the two phases of a refractory period?
Absolute refractory (blanking) period
Relative refractory period
What is the difference between absolute and relative refractory periods?
Absolute refractory periods device cannot see or respond to impulses
Relative refractory period device can see impulses but response is limited
Asynchronous pacing
programmed mode of pacing that delivers a stimulus at a fixed rate independently of any atrial or ventricular activity
What is the purpose for triggered modes of pacing?
Temporary diagnostic use
avoid inappropriate device inhibition owing to interference
How does triggered modes work?
Paces when there is an intrinsic event detected
MVP
Medtronic algorithm that minimizes RV pacing by using AAI(R) pacing when ventricular beats are sensed between two atrial beats
What are the three main timing cycles in the atrial channel?
Atrial alert period
AV delay
PVARP
What are the three main timing cycles in the ventricular channel?
Ventricular alert period
Blanking period/crosstalk detection window
Ventricular refractory period
What is the cycle of periods on the atrial channel?
alert period, atrial event, AV delay, PVARP
What two periods encompass the atrial refractory period?
PVAB and PVARP
