Implantable Devices

Question 1

signs of SA node dysfunction

Answer 1

sinus bradycardia <60 bpm
sinus arrest
PSVT - atrial fibrillation/flutter

Question 2

pacemaker types

Answer 2

temporary or permanent
both have implanted pulse generator and lead wire leading into the heart with an electrode

Question 3

temporary pacemaker types

Answer 3

transcutaneous: electrodes on chest wall, painful
transatrial: electrodes on atria, uncommon
transvenous: electrodes on ventricle from the femoral artery pathway

Question 4

indications for temporary pacemaker

Answer 4

acute MI
post cardiac surgery
drug toxicity
bridge to permanent pacemaker

Question 5

permanent pacemaker indications

Answer 5

SA node dysfunction
2nd degree AV block, bradycardia
3rd degree AV block w bradycardia, CHF, atrial fibrillation/flutter, asystole periods
acute anterior MI w AV block
severe bundle branch blocks

Question 6

conditions warranting a pacemaker

Answer 6

syncope
dizziness
CHF
mental confusion
palpatations
dyspnea
exercise intolerance

Question 7

heart chamber pacing: atrial

Answer 7

electrode in R atrium, increase atrial contribution to ventricular filling, increase CO by stimulating SA/AV node

Question 8

heart chamber pacing: ventricular

Answer 8

electrode placed in R ventricle
increased ventricular rate when there is a heart block/bradycardia

Question 9

heart chamber pacing: dual chamber

Answer 9

electrodes in both R atrium and ventricle
maintain timing between the two chambers to increase CO

Question 10

Modes of pacing

pacemaker

Answer 10

fixed: preset firing rate
demand: fires only when HR falls below certain rate
rate-responsive: fires depending on pt activity level, increases pace with increased CO

Question 11

mechanisms of demand pacemakers

Answer 11

sensing mechanism: determine intrinsic rate and whether it’s adequate
pacing mechanism: triggered when no intrinsic complex occurs in set time

Question 12

ICD indications

Answer 12

implantable cardioverter defibrillator
for life threatening arrhythmias

Question 13

ICD mechanism

Answer 13

shocks heart to cardiovert when fatal arrhythmia detected
quick and painful, can cause pt to collapse
CRT - cardiac resynchronization device used to pace both ventricles at once

Question 13

PT implications for pacemakers/ICDs

Answer 13

do not pull out leads/disconnect
don’t tension wires when transferring
patient education to: avoid electrical devices with magnetic field
post op instructions: bedrest, L arm sling 24 hrs, L UE avoid shoulder flexion/abduction, no lifting > 5 lbs, no driving until pacemaker cleared to be working

Question 14

Holter monitor

Answer 14

portable device to continuously monitor heart electrical activity 24+ hours
observe occasional cardiac arrhythmias

Question 15

LVAD mechanism

Answer 15

L ventricular assist device
mechanical pump assuming function of damaged ventricle to restore CO
for pts with advanced heart failure

Question 16

LVAD types

Answer 16

pulsatile: noisy
Axial: continuous flow, modern, quiet

Question 17

VAD indications

Answer 17

bridge to transplant: heart transplant candidate
destination therapy: long term, perm implant for class 3-4 HF
5-10 years survival

Question 18

criteria for VAD implant

Answer 18

2 hospital admissions
not improving on medications
hyponatremia
hypovolemic
ionotrope dependent (meds)
EF < 35%

Question 19

VAD functions

Answer 19

restore CO, BP
reduce L ventricle work, avoid more damage
reduce pulmonary pressure
improve body perfusion

Question 20

+++ pump flow

Answer 20

normal for larger pts due to larger CO
could also indicate clot formation in pump

Question 21

— pump flow

Answer 21

normal for smaller pts
or pt is hypovolemic and needs fluid bolus

Question 22

vitals for VAD pts

Answer 22

may not have pulse due to pump
get MAP w doppler, HR w telemetry
O2 sats hard to get

Question 23

impella

Answer 23

mechanical circulatory assist device
endovascular
mini VAD pumps blood from L ventricle to aorta

Question 24

indications for impella

Answer 24

pts w MI and cardiogenic shock needing support
complicated PTCA
severe uncompensated HF
myocarditis
rest needed for ventricle to reduce O2 demand
off pump CABG
approved for used 6hrs-14 days+~

Question 25

PT precautions after VAD placement

Answer 25

arousal level
anticoagulants
vasopressors/ionotropes
O2 support
arrhythmias
pulmonary a. cath
arterial lines
CVP line
chest tube
sternal precautinos
balloon pump removal
EKG picks up native heart contraction

Question 26

contraindications to PT after VAD

Answer 26

VAD malfunction
intra aortic balloon pump
open chest
active bleeding
hemodynamic instability like BP fluctuation
full ventilator support
symptoms appear: angina, EKG changes, dyspnea 5+, O2 sats drop, systolic BP drop

Question 27

PT goals after VAD

Answer 27

function
strict! sternal precautions
pulmonary care
reduce kyphotic posture
abdominal binder
pt education on battery life
heart rate blunted by beta blockers
RPE11-13