ECG Flashcards
Regular Rhythm definition
R-R interval same across tracing
Irregular rhythm definition
R-R interval varies across tracing
NSR definition
p wave before each QRS, QRS follows each P-wave, P-wave axis is normal (+ in 2/3 Leads I, II, AVF), rate is between 60 - 100
Normal Axis
-30 - 90 degrees (positive QRS in Lead I, II)
Left Axis Deviation
< -30
Right Axis Deviation
> 90 degrees
LBBB Complete definition
QRS > 120 msec, deep broad S wave in V1, v2, broad notched R wave in V4, V5 and usually I and aVL, secondary ST/T changes (+ST in V1-2, -ST in V4-5, I, AVL)
RBBB Definition
QRS > 120 msec, positive QRS in leads V1 (rSR, rsr), broad S wave in I, V5-6, T-wave inversion in V1-2,
Left Anterior Fascicular block
left axis deviation, small q and prominent R in leads I, AvL, small r and prominent S in leads II, III, aVF
Left Posterior fascicular block
Right axis deviation (110 - 180), small r and prominent S in leads I, aVL, small q and prominent R in leads II, III, aVF
Bifascicular block
RBBB + RAD/LAD
LVH DDx
left anterior hemiblock, inferior MI, WPW, RV pacing, elevated diaphragm, normal variant, endocardial cushion defect
RVH DDx
RVH, L posterior hemiblock, PE, COPD, lateral MI, WPW, dextrocardia, septal defects
LVH Definition
S in V1 + R in V5 or V6 is > 35 mm above age 40 (>50 mm for ages 31-40, > 45 mm for ages 21-30), R in aVL > 11 mm, R in I + S in III > 25 mm, LV strain pattern (asymetric ST depression and T wave inversion in leads I, AvL< V4-6
RVH definition
RAD, R/S Ratio > 1 or qR in lead V1, RV strain pattern (ST depression and T-wave inversion in leads V1-2)
Progression of ECG Changes in STEMI
Acute: (hours - days): ST elevation
Recent: (weeks - months) T wave inversion
Old: (months - years) persistent Q waves
LBBB DDx
anterior MI, aortic stenosis, HTN, dilated CM, primary degenerative disease, hyperkalemia, digoxin toxicity
DDx of T-wave inversion
normal pediatrics (v1-v3), persistent juvenile T-waves, myocardial ischemia/MI, LBBB, RBBB, LVH and RVH (strain pattern), PE, hypertrophic cardiomyopathy, raised ICP
RBBB DDx
RVH/cor pulmonale, PE, ischemic heart disease, rheumatic disease, myocarditis, cardiomyopathy, degenerative disease, congenitla disease (ASD)
Brugada syndrome definition
ECG finding + clinical criteria (documented VF or VTach, +FHx of SCD, syncope); MGMT: ICD