EKG Reading

 
The Dr. Boyd Method

RRIAHI (Rate, Rhythm, Interval, Axis, Hypertrophy, Infarction)

 1. Rate
 2. Rhythm, AXIS  If II is net negative LAD > -30.
 3. P - inverted or biphasic Ps in II = ectopic or junctional rhythm
 4. PNormal - upright in II, III, AVF, inverted in AVR, < 2.5 high, < 3 wide,   biphed in V1
 5. (LAE) PMitral  - notched > .04 P in I & II, slurred, diphasic, negative 'M-shaped' P in V1 - all that don't meet this criteria are 'Left Atrial Abnormality'
 6. (RAE) PPulmonale - Peaked P in II, III, AVF, diphasic or inverted in V1
 7. PR (nl .12 - .20), block if > .2  PR < 0.12 is WPW or LGL
 8. QRS (nl .04 - .12), ICBBB (0.10-0.12)
 9. AHLADqRIrSIII(-30), qR in I and an rS in III & usu in II & AVF
10. PHRADrSIqRIII(+120) usu w/ RBBB
11.  A normal QRS has and RS in  V1 and QRS in V6
12. LBBB - QRS > .12, no Q in I,V5,V6 monomorphic R in I,V5,V6, ST&T displacement opposite QRS
13. RBBB - QRS > .12, rSR' "bunny ears" in precordial leads, slurred S waves I, V5, V6
14. RVH - Tall R in V1, (R-S ratio > 1 in V1), S > R in V6, NL QRS, RAD, ST depression, T inversion in V1, V2 possibly with strain pattern which is assymetric vs symmetric T inversions with chest pain as would present in posterior infarct, R' in V1 in RBBB > 10 suggestive
15. LVH - Tall R in AVL > 7.5 mm (Scott)
16. APE - S1Q3T3
17. A normal T is not greater than 1/2 height of QRS
18. If QT/RR < 40% or look for long QT (like .6) NL = .36 - .41
19. Wellen's syndrome - Biphasic STe in V2&V3
20. Brugada - RBBB, STe V1-V3, Ti - 268 (requires ICD) 1/2 SCD in young
21. Wellen - 265 - critical narrowing of prox LAD presents as inverted T waves (1&6 below in TiDDX
22. ARVD - arrhythmogenic RV dysplasia w/ epsilon waves.
23. WPW
24. AIVR - accelerated idioventricular rhythm (VT < 100)
25. Yamaguchi's syndrome - Apical hypertrophic cardiomyopathy - deep, narrow, spade-like Tis.
26. QT-U prologation - Cerebellar hemorrhage. REF

Differential Diagnoses:
ST-elevation
ST-depression
T wave inversion
Hyperacute T Waves

Practice:


http://lifeinthefastlane.com/ecg-library/basics/t-wave/
http://ems12lead.com/tag/strain-pattern/
http://library.med.utah.edu/kw/ecg/
www.caccn.ca


Anything that increases QT interval can cause Torsades - an intermediary between vtac and vfib. 

ST segment depression in aVL: a sensitive marker for acute inferior myocardial infarction

What can an EKG tell you ? REF

1. chamber size

2. conduction defects

3. MI

4. prolonged QT

5. rhythm.  

Medstudy:

Hypokalemia - flattened T waves (expect hypokalemia & hypochloremic metabolic alkalosis in emesis).

Hyperkalemia - peaked T waves.

Hypermagnesemia - prolonged PR and QRS intervals.

WPW - delta waves.

Digitalis - shortened QTC interval associated with ST depression.

Hypercalcemia - short QT interval due to shortened myocardial action potential, possible ST elevations.

HOCM and mitral valve prolapse are the only conditions that have a murmur that increases with standing.

-- To differentiate use hand grip - in HOCM it decreases the M and in MVP it increases the M.