ECGs by diagnosis

Background

1. Poor R wave progression: no r's by V4

STEMI

1. Posterior
   1. ST depression in V1-V2
   2. R-S ratio of >1 in V1 or V2
   3. ST elevation >1 in V7-9
   4. Often accompanied by inferior ST changes
   5. Often accompanied by RV MI
2. Anterior
   1. ST depression in II, III, aVF usually due to high lateral ST elevation (I, aVL)
3. Inferior
   1. Look at I, aVL for reciprocal changes (ST depression or TWI)
      1. If no changes pt probably not having an inf STEMI

Aneurysm

1. ST elevation > 2wk

Pericarditis

• See Pericarditis#ECG

Electrolyte Disorders

Hyperkalemia

1. 5.5-6.6 -> tall peaked T, deep S in I and V6, QRS nml
2. 7.0-8.0 -> QRS widens, slurred initial and term QRS, ST elevation, low wide P's, AV blocks, SA arrest, bradycardia.
3. >8.0 -> widened QRS, Vfib, asystole.

Hypokalemia

1. 3.0-3.5 no change or flat T' sand U's in V2-3, QT interval and QRS nml.
2. 2.7-3.0 U taller, T smaller, esp. V2-3
3. <2.6 ECG change includes tall U's, QT and QRS wnl.

Hypercalcemia

1. Increased QRS duration (slight)
2. ST short or absent
3. Short corrected QT.
4. PR long

Hypocalcemia

1. slight decrease in QRS.
2. ST and corrected QT long
3. PR short.
4. T's flat to inverted.

CNS

1. SAH, IC bleed, stroke, can see diffuse wide deep, blunted inverted T's. and QT prolonged

Pacemakers

1. Should be in the apex of R vent
2. ECG should mimic LBBB w/ LAD

PE

1. S1Q3T3
   1. (good specificity, poor sensitiviy)

See Also

• ST Segment Elevation
• ST Segment Depression

Source

DONALDSON 17/09 (Adapted from Niemann/Lampe)