Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
43 Cards in this Set
- Front
- Back
- 3rd side (hint)
ECG nml axis describe lead I & aVF
|
Both +
|
|
|
LAD describe leads I & aVF
|
I = + aVF (-)
|
|
|
RAD describe I & aVF
|
I (neg) aVF (+)
|
|
|
Extreme axis describe I & aVF
|
both negative
|
|
|
LAD is associated with what disorder?
|
Left anterior hemiblock seen in CAD
|
|
|
RAD is seen when?
|
often nml finding in children and young adults
Left posterior hemiblock RVH, pulm HTN |
|
|
How do you determine HR on an ECG
|
1500/# of little squares
300/# of big squares |
|
|
What is the nml P-R interval? What does a long PR inerval mean? What does a short P-R mean?
|
3-5 small squares should be no longer than 1 big square.
1 degree block short could be WPW |
|
|
What are the causes of a widened QRS?
|
BBB, PVC, TCA toxicity, WPW
|
4
|
|
What is the nml duration of a QRS?
|
1/2 big square
<100 ms |
|
|
What is the nml QT interval? How do you correct for time?
|
QTc = 340-430 ms
QTc= QT/sq rt(RR in sec) Rule of thumb QT should be 40% of RR |
|
|
What do the squares on the ECG mean in terms of time?
|
Big square = 0.2 sec or 200 ms
small square = 40 ms |
|
|
What arrthymia develops from a prolonged QT inerval?
|
Torsades de pointes
|
|
|
What are the more common causes of prolonged QT interval?
|
TCA overdose
Hypo Ca, Mg, K quinidine, procanamide, amiodarone, starvation, CNS injury, liquid protein diet |
10
|
|
What can non-sedating antihistamines do to an ECG?
|
Prolong the QT interval exacerbated by erthromycin, ketakonozole, hepatic dysfunction.
|
|
|
35 yo Female with allergies resently prescribed Hismanal who was noted to have an abnml ECG. What was the cause? She has an infection what should you not prescribe?
|
QT prolongation exacerbated by erthromycin
|
|
|
What shortens the QT
|
hypercalcemia and digitalis
|
2
|
|
Describe the nml p wave
|
< 2 mm high
< 120 mm (3 sm squares wide) + in lead II and - aVR also look in V1 |
|
|
Describe the p wave in right atrial enlargement? Left atrial enlargement
|
RAE = peaked p
LAE = widened p wave neg V1 |
|
|
Peaked T waves are associated with what?
|
Hyperkalemia
Hyperacute MI intracerebral hemorrahge V1 V2 evloving post MI |
think about symetry of t wave
|
|
Focal flipped T waves?
Unknown question |
V1-V2 RBBB, LVH
I aVL V6 LBBB |
|
|
Prominent U waves indicate what
|
Increased tendency to Toorsades de pointes, hypokalemia, bradycardia, digitalis, amiodarone
|
|
|
Diffuse flipped T waves?
|
Pericarditis
diffuse ischemia metabolic abnml Intracerebral hemmorhage |
4
|
|
What is the sig of negative U waves
|
U waves in a different direction from T wave always significant casues are ischemia, HTN Aortic valve dz, RVH
|
|
|
What are the 3 main causes of ST elevation?
|
Acute MI
Prinzmetal angina Pericarditis or myocarditis |
3
|
|
Describe 4 rules to determine axis on an ECG?
|
1. I & aVF both + = nml
2. I(+) aVF(-) = LAD 3. I(-) aVF(-) = extreme axis 4. I(-) aVF(+) = RAD |
|
|
In what leads are ischemic changes seen in a septal MI?
|
V1-V2
|
|
|
In what leads are ischemic changes seen in a anteroseptal MI?
|
V1-V4
|
|
|
In what leads are ischemic changes seen in a anerior MI?
|
V3-V4
|
|
|
In what leads are ischemic changes seen in a lateral MI?
|
I aVL V6
|
|
|
In what leads are ischemic changes seen in a posterior MI?
|
Tall R waves in V1-V2
|
|
|
In what leads are ischemic changes seen in a inferior MI?
|
II, III, aVF
|
|
|
What does ST depression indicate?
|
1. subendocarial ischemia
2. V1-V2 = posterior MI 3. Dig tox 4. LVH 5. Hypokalemia 6. LV strain (ST depression with flipped T Waves) |
|
|
What are the criteria for LVH?
|
Flipped T waves in V1-V2
S in V1 + R in V5 35 mm R peak time > 50ms watch out for WPW! May also have strain pattern ST depression + flipped T waves RV5>25-35 |
|
|
Describe the specificity and sensitivity of voltage criteria for LVH & RVH
|
Specificty is fairly good (low FP) Sensitivity is horrible (lots of FN)
|
|
|
What are the ECG criteria for RVH
|
RAD
ST depression + fipped T wave V1 Large R wave V1 |
|
|
Criteria for LBBB
|
QRS 120-180ms 3-4.5 sqs
RR' V6 SS' V1 T wave flipped |
|
|
Criteria for RBBB
|
QRS >120 ms 3sqs
RSR' in V1 |
|
|
When interpreting an ECG, right ventricular hypertrophy (RVH) can mimic which of the following conditions?
A. LBBB B. AV block C. True posterior MI D. LAFB E. LPFB |
The prominent anterior forces seen in RVH are also seen in a number of other conditions including a true posterior MI. Thus, RVH is sometimes referred to as a pseudoinfarct.
RBBB and WPW could also result in prominent anterior forces but they may be distinguished in other ways. (rSR' morphology in V1, delta waves, and short PR.) |
|
|
What are the ECG criteria for RVH?
|
Right axis deviation ( I negative AVF +)
R wave > S wave in V1 & S wave > R wave in V6 |
|
|
What are the ECG criteria for LVH?
|
R in V5,6 + S in V1,2 >35
R in AVL >13 mm Repolarization abnml |
|
|
List the 7 potential causes of arrhythimas?
|
HIS DEBS (Acronym)
Hypoxia Ischemia & Irritability Sympathetic stimulation Drugs Electrolyte disturbances Bradycardia Stretch such as in CHF LAE |
|
|
What are the 4 most important questions in determining the origin of an arrhythmia?
|
1. Are nml P waves present?
2. QRS duration < 0.12 sec? 3. Relationship between P & QRS? 4. Regular or Irregular? |
|