12 leads Flashcards
8.5% of adults over 20 yrs have a cardiac ischemic diagnosis (T/f)
true
what is PCI
percutaneous coronary Intervention, guide wire and a catheter is inserted through coronary arteries into the aorta and to the coronary arteries in the heart. Dye is injected to identify blockages. Then another catheter is inserted with a balloon which is then inflated. A stent is left in place to keep the vessels lumen open.
when should a 12 lead be done?
10 mins after arrival when pt is experiencing infection, cp, sob, pneumonia, pneumothroax, etc.
what is CAD?
when plaque build up occurs in the coronary arteries restricting blood flow—> MI
RCA
right coronary artery branches off the base of the aorta and follows down the AV sulcus.
RCA splits intot he RMA and PDA
RCA feeds….
right atria ( SA node), RV, & inferior wall of LV and feeds the AV node in most pt
LCA
branches off the base of the aorta into 2 main arteries LAD and circumflex
the LAD feeds
anterior & septal portions of the left & right ventricles
Left circumflex feeds…
LA, lateral & posterior LV
Coronary conduction disease:
when there is a delay in conduction between the AV node and the bundle of HIS due to faulty “atrial kick”
normal length of Pr
0.12-0.20
Normal qrs length
0.08s-0.12s
V1
placed at the 4th ICS to the right of hte sternal boarder
V2
4th ics left of sternum
V3
half way between V2 and V4
V4
5th ics midclavicular line
V5
5th ICS anterior axillary line
V6
mid axillary line level w v4-v5
prep for ecg acquisition?
have hair, dry skin, keep pt still
contiguous leads?
2 leads that look at the same areas of the heart at different angles.
what are some contiguous leads?
Lead 2,3, avf look at the inferior portions of the heart in slightly different directions.
goal of 12 lead?
STEMI Identification
why does ischemia occur?
lack of O2 in cardiac tissue due to blockage
what does ischemia look like on 12 lead?
St depression >1mm/or T wave inversion
cardiac injury and how i looks on 12 lead?
due to prolonged ischemia ( MI). presents with hyperacute T-waves (early) that progresses to ST elevation, >2mm in leads 1-3 & >1mm in all other leads
What is an infarct and what does the ecg look like?
death of cardiac tissue. Can have patho Q wave ( depth and wide >/=1mm or 25% of r wave amp & ST elevation.
what is the gold standard for MI diagnosis?
angio (PCI)
10% of the population left lateral wall of the heart is fed by the…..
circumflex
What are your inferior leads? what does it show you?
Lead 2, 3 & aVF. shows inferioir portion of right ventricle and fed by RCA (PDA)
If you have elevation in the inferior leads where can u expect to see reciprocal changes?
lateral leads: Lead 1, AvL, V5-v6
RVI is contraindication for what drug use?
NTG bc RV is preload dependent
What are the tell tale signs for RVI?
Bradycardia, hypotension, JVD, clear chest ascultations
anterior leads? where would reciprocal changes be seen?
V4 & V3 views the anterior portion of LV supplied by LAD. Elevation in posterior leads(2,3, AVF) ( prompts 15 lead) –> posterior MI
Septal leads and where reciprocal changes can be found.
V1 & V2 . reciprocal changes are in 1,2,AVF. (MI is usually anteriorseptal)
Lateral leads and where are reciprocal changes?
fed by circumflex
high= Lead 1 & AvL
Low:V5 & V6–> shows ST elevation
reciprocal changes: lead 3 and AVF, Lead 2. Should show depression confirming lateral MI
how would you Identify posterior wall MI?
St depression in anterior leads (V4, V3) and elevation in leads Inferior 2-3 & AvF and reciprocal changes in V4, V3. Need 15 lead (V7-V9 on back)
when doing your interpretation what should you include?
location in heart ex: inferior wall MI what leads involved ex: due to elevation in leads 2, 3, avf. note what artery is occluded
Mi TX:
titrate o2 >/=94
asa low dose
iv
ntg x 3 sprays max
N-STEMI is an infarct of the…
endocardium, inside of the heart of the heart out
while a STEMI is the Outside of the heart in
STEMI Bypass criteria
age: >/= 18 yrs
Other: onset </= 12hrs, CP or pain consistent with MI, 12 lead must indicate acute MI/STEMI
(at least >2mm in leads V1-V3 in at least 2 contiguous leads) or 1mm elevation in any other 2 anatomically contiguous leads, & the 12 lead interpretation and medic must agree.
Other criteria for STEMI bypass?
- must not be CTAS 1, A?W must be secure, 12 lead must not have STEMI imitators, Transport to PIC <60 mins from contact, if pt is experiencing complication that PCP can manage:
pt complications needing PCP management….
moderate to severe resp distress needing cpap, hemodynamic instability must be managed, must not be symptomatic SBP<90mmHG, VSA w rosc
Pt complications needing acp diversion as follows….
inadequate vent despite asistance, hemodynamic instability unresponsive to care or VSA W no ROSC
how would you determine RVI?
move leads V4-V6 on the right side of pt chest and label them on ECG w “r”. Identify if there is ST elevation in the leads= + STEMI
