ECG Flashcards
STEMI Criteria in Men over 40
2mm in V2-V3, 1mm in all other leads
STEMI Criteria in Men under 40
2.5 mm in v2-v3, 1mm in all other leads
STEMI criteria for women, regardless of age
1.5 mm in V2-V3, 1mm in all other leads.
What classifies a STEMI on the ecg
ST elevation in 2 contiguous leads with reciprocal depression in other leads
What will you see in the initial onset of transmural ischemia
Hyper acute T wave
What is the criteria for pathological q waves?
1 small box or 0.04s wide. 2mm deep, and 25% of depth of qrs complex
What are the 3 atrial rhythms that could be present, when you have a tachycardia with no discernable p waves and irregularly irregular complexes?
MAT, Atrial Fib with RVR, Wandering Atrial Pacemaker
When you have a Tachycardic Regular rhythm, what are the 3 options it could be?
SVT, Atrial Flutter, Sinus Tachycardia
Which precordial leads look at which area of the heart? What are they supplied by?
V1 - V2 : Septal, LAD. V3-V4 : Anterior, LAD. V5-V6: Lateral (Low), LAD/LCX
Which limb leads look at which area of the heart, what are they supplied by?
1-AVL: High Lateral, LCX. 2-3-avF: Inferior, RCA. AVR: on its own, Left main, Prox LAD, 3 vessel disease
Pathologic Q Wave Criteria
0.4s or 1mm wide or greater, greater than 25% of QRS complex, 2mm deep, seen in leads v1-v3
What could peaked T waves be an indication of?
Hyperkalemia
What is important to note about which direction biphasic t waves go?
If it goes up and then down it indicates ischemia, if it goes down and then up it indicates hypokalemia
What are the characteristics of P Pulmonale, and what does it indicate?
Peaked p waves in lead 1 and v1, indicates right atrial enlargement
What are the criteria for P Mitrale and what does it indicate?
Humped p wave in lead 1 and a biphasic p in a v1, indicated left atrial enlargement.
What does a variable p wave morphology indicate?
Multifocal atrial rhythms
What is important about an inverted p wave?
Ectopic atrial or junctional rhythms
What is a normal PRI?
0.12-0.20s
What is a short pri?
Less than 0.12s
What is important to remember in the setting of a short PRI?
Could be due to a pre-excitation syndrome (WPW) or an Junctional rhythm (absent or abnormal p wave or retrograde p waves.)
What is important to remember about PR segment abnormalities? Specifically depression and elevation?
PR Depression - Pericarditis
Atrial Ischemia in the setting of MI. PR depression or elevation.
What leads would small q waves be normal?
Leads I, avL, v5-v6.
What important q wave abnormalities may be found on an ECG?
V1-V3 not normally seen, if not found in v5-v6 consider it abnormal (unless in LBBB)
What are the main points to remember when initially evaluating the QRS complex?
Narrow vs Wide
Voltage (Height)
Morphologies not to miss
What is important to realize about wide complex QRS?
Either ventricular in origin or abberantly conducted supraventricular complexes (such as BBB, Hyperkalemia or Sodium Channel blockade)
Narrow QRS morphology origins?
SA node -> NSR
Atria —> abnormal p waves / flutter waves / fibrillatory waves
AV node/Junction -> absent p wave or PRI less than .12
Wide Complex Criteria?
Greater than .10 = abnormal
Greater than .12 = BBB or Ventricular Rhythm
Left Ventricular Hypertrophy Criteria?
S wave in v1-v2 + R wave in v5-v6 = 35 mm or greater.
Voltage criteria must be accompanied with some leads that have non-voltage criteria.
Left Axis Deviation
ST depression and TWI in lateral leads
Right Ventricular Hypertrophy Criteria
Right Axis Deviation
Dominant R Wave in V1 (>7mm tall or R/S ratio >1)
Dominant S Wave in V5 or V6 (>7mm deep or R/S ratio <1)
QRS less than 120 ms
Right Ventricular Strain Pattern Criteria? Associated Features of it?
ST depression and TWI in leads corresponding to R ventricle:
R Precordials - V1-V3 +/- V4 and Inferior leads often most pronounced in lead III.
Associated Features: R Axis Deviation, Dominant R wave in V1 Dominant S wave in V5-V6
What could be the causes of R Ventricular Strain Pattern?
Pulmonary HTN
Mitral Stenosis
Pulmonary Embolism
Cor Pulmonale (Chronic Lung Disease)
Congenital Heart Disease (Pulmonary Stenosis, Tetrology of Fallot)
Arrhythmogenic Right Ventricular Dysplasia
Left Ventricular Strain Pattern?
ST Elevation V1-V4 with deep S wave
ST depression and TWI in V5-V6
Generally proceeds from most elevated V1/V2 to most depressed V6.
RBBB Criteria?
QRS > 120ms
RsR’ in V1-V3 (“M shaped QRS Complex)
Wide slurred S wave in lateral leads (I,avL, V5-V6)
LBBB Criteria?
QRS > 120ms
Dominant S wave in V1
Broad monophasic R wave in the lateral leads (I, avL, V5-V6)
Absence of Q waves in lateral leads
Prolonged R wave peak time in V5-V6.
STE and upright T wave in leads with negative qrs complex or dominant S wave
STD and TWI in leads with positive qrs complex or dominant R wave