ECG Flashcards
What does axis deviation mean?
Same direction = hypertrophy
Opposite direction = ischemia
What does low voltage indicate?
Obstruction to ECG (pericarditis)
What are the 4 stemi mimics?
1) left ventricular hypertrophy
2) pericarditis
3) left bundle branch block
4) benign early repolarization
What vessel supplies the anterior heart and what leads view it?
LAD
AVR, V1, V2
What vessel supplies the high lateral heart and which leads view it?
LCx
AVL, lead I
Which vessel supplies the inferior heart and which leads view it?
RCA
Lead II, lead III, AVF
Which vessel supplies the lateral heart and which leads view it?
LAD
V3 V4
Which vessels supply the SA and AV nodes with blood?
RCA and LCx
On a 12 lead RV dysfunction can be observed by:
STE in II, III and aVF (inferior)
Reciprocal changes in I and v6 (high lateral)
Reciprocal changes in v2 and v3 (anterior)
What vessel supplies blood to the right ventricle?
The RCA but sometimes LCx in certain populations
How to view right ventricle with ecg
V4R
Place electrode in 5th intercostal space and at the right mid clavicular line
What is standard ecg calibration?
1 mV 10 mm (10 boxes) tall
0.20 sec (5 boxes) wide
Where to view atrial enlargement?
Lead II and v1
LAE
Left atrial enlargement
Camel hump p waves in lead II (p mitral) and scoop after p wave in v1
RAE
Right atrial enlargement
Increased p wave amplitude over 2.5mm in lead II (p pulmonale) and biphasic p waves in v1
Where to view ventricular enlargement?
The QRS complex in v1&v2 and v5&v6
LVH
Left ventricular hypertrophy
Deepest S wave in v1v2 and tellers R wave in v5v6 add up to 35+
AND / OR
R-wave in aVL 12mm or over
RVH
Right ventricular hypertrophy
Harder to diagnose
Findings include:
RAD
RAE
Low voltage QRS
Strain in v1-3 or inferior leads
Tall R wave v1
Where is t waves inversion clinically relevant?
Lead II, lead III and aVF
What makes a Q wave pathological?
Over 1 small box wide or 1/3 deflection length of the R wave
(Sign of previous MI)
Orthodromic AVRT
Antegrade conduction through atrioventicular node
(No delta wave)
Antidromic AVRT
Retrograde conduction through atrioventricular node
(Delta wave often hides p wave)
Where to assess axis deviation?
Lead I and aVF
Pneumothorax
Gas that has entered and accumulated in the plural space causing separation of the visceral and parietal pleura