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R wave transition
In V1-V6, the QRS complex changes from predominately negative (QrS) to predominately positive (qRs) w/ the R/S ratio becoming >1. This usually occurs at V3 or V4
R atrial enlargement indicators
1. P in INFERIOR leads PEAKED (>2.5 mm); 2. UPWARD half of diphasic P in V1 is 2X larger than downward part
L atrial enlargement indicators
1. P waves in INFERIOR leads >120 ms & DOUBLE-peaked;
2. DOWNWARD part of diphasic P waves in V1 is 2X larger than upward part
P-wave indicators of mitral valve Dz (p-mitrale)
1. Camel-humped P in INFERIOR leads
2. BOTH L & R Atrial abnormality
1. RAD ((aVL NEG, aVF POS)
2. R-progression in V1-V6 reversed;
3. In V1: R > 7mm or HT of R >Depth of S
1. S in V1+ R in V5 >35 mm;
2. R in V5 >26 mm
3. R in Lead 1 >14 mm
4. ST depression and T inversion in LEFT precordial leads (V4-6) show LVH ischemia
MaRRoW: (M is RsR' in V1 and W is rSr" in V6
QRS always >120 ms
1. RsR' in V1, V2, or V3 (Septal or Anterior)
2. DEEP/WIDE S in Lead (1 or) 2 & V6
3. T may be inverted in Septal (V1/V2) leads
WiLLiaM: (W is rSr' in V1 and M is RsR' in V6).
QRS always >120 ms
1. W is DEEP/WIDE (r)S(r') complex in V1;
2. M is TALL/WIDE R(s) in lead (1 or) 2 & V6
3. T wave is always opposite QRS.
Coronary occlusion associated w/ Anterior MI
Left Anterior Descending (LAD) = Anterior Interventricular
Posterior MI Indicators
ST DEPRESSION in anterior (V3, V4) (RECIPROCAL anterior ST elevation); TALL R in V1, V2 w/ no RAD
Left Anterior Fascicular Block (Left Hemi-block)
1. Left axis deviation (-45 to -90 degrees) 2. Tiny Q's & Large R's in 1 & aVL
3. rS in inferior leads (II, III, aVF)
4. Delayed R wave transition. S wave in V5-V6
Left Posterior Fascicular Block indicators
2. Tiny R & Deep S in 1 & aVL
3. Tiny Q & Large R in inferior leads (II, III, aVF)
High Atrial pressure from HTN, CHF, or VHD cause re-entry around a counter-clockwise path at Tricuspid valve
Atrial rate 220-320, typically right at 300;
Sawtooth "flutter waves" in Inferior leads;
Normal QRS in 2:1, 4:1 other pattern
Jim's 2nd Law
A heart rate of exactly 150 is 2:1 A-flutter until proven otherwise (Look for flutter waves in Inferior leads)
How to prove a 300 bpm trace is 2:1 A-Flutter
Adenosine stops QRS for 6-10 sec; Now count the p waves. One/box = 300. See any flutter waves
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