CMC ECG MASTERS
  • Home
    • About Us
    • EM GuideWire
    • CMC Ed Masters
    • Ped EM Morsels
  • Basics
  • P Waves
    • Sinus
    • Not sinus
    • Absent
  • PR interval
    • Short PR
    • Prolonged PR
    • Variable PR
  • QRS
    • Wide
    • Axis >
      • LAD
      • RAD
    • Amplitude >
      • High Voltage
      • Low Voltage
      • Alternans
    • R Wave Progression
    • Pathological Q waves
  • ST Segments
    • ST Elevation
    • ST Depression
  • T Waves
    • Flat, Bifid, or Notched
    • Inverted
  • QT intervals
    • Prolonged QT
    • Short QT
  • Patterns
    • STEMI
    • Pulmonary Embolism
    • Ventricular Hypertrophy
    • Pulmonary Disease
    • ST-T Patterns
    • Electrolyte Abnormalities
    • Cases >
      • Case 1
      • Case 2
      • Case 3
      • Case 4
      • Case 5
      • Case 6
      • Case 7
      • Case 8
      • Case 9
      • Case 10
      • Case 11
      • Case 12
      • Case 13
      • Case 14
      • Case 15
      • Case 16
      • Case 17
      • Case 18
      • Case 19
  • Interpreter

Pathological q Waves

Picture
   Width: ≥  0.03s
   Depth: ≥  ⅓ of QRS amplitude
   Needs to be present in at least 2 neighboring leads
MYOCARDIAL INFARCTION
ECG Leads
 Location of MI
Probable Culprit
II, III, aVF (±V5,V6)
Inferior
RCA (or dominant LCX)
Mirror image V1-V2 (R­, ST¯, T­)
Posterolateral
LCX
II-III-aVF, plus V1 and RV4
Inferior + RV
Proximal RCA
V1-V4
Anteroseptal
LAD
V1-V6 (± I, aVL)
Extensive Anterior
LAD
I, aVL, V4-V6  ​
Lateral
LCX
I, aVL, V2 (± mirror image III)
High Lateral
LAD-D1
NONINFARCTION Q WAVES
  • LBBB
  • WPW
  • LVH
  • Hyperkalemia
CLINICAL SIGNIFICANCE
  • Patient probably had an MI
  • MI probably large or transmural
  • Likelihood of no viability

REMOTE MI WITH NONSPECIFIC IVCD
  • Increased risk of VT/VF, sudden cardiac death
  • Syncope:
    • more likely to be malignant, arrhythmic
Coexisting considerations:
  • Chest pain
    • more likely of cardiac origin
  • ST elevation
    • more likely of coronary etiology
  • Cardiomyopathy, CHF
    • more likely ischemic
  • Ventricular tachycardia
    • more likely ischemic-malignant
  • Unexplained syncope
    • more likely due to VT
  • Preoperative evaluation
    • intermediate risk factor
Back to Progression
Move on to ST Segments
  • Home
    • About Us
    • EM GuideWire
    • CMC Ed Masters
    • Ped EM Morsels
  • Basics
  • P Waves
    • Sinus
    • Not sinus
    • Absent
  • PR interval
    • Short PR
    • Prolonged PR
    • Variable PR
  • QRS
    • Wide
    • Axis >
      • LAD
      • RAD
    • Amplitude >
      • High Voltage
      • Low Voltage
      • Alternans
    • R Wave Progression
    • Pathological Q waves
  • ST Segments
    • ST Elevation
    • ST Depression
  • T Waves
    • Flat, Bifid, or Notched
    • Inverted
  • QT intervals
    • Prolonged QT
    • Short QT
  • Patterns
    • STEMI
    • Pulmonary Embolism
    • Ventricular Hypertrophy
    • Pulmonary Disease
    • ST-T Patterns
    • Electrolyte Abnormalities
    • Cases >
      • Case 1
      • Case 2
      • Case 3
      • Case 4
      • Case 5
      • Case 6
      • Case 7
      • Case 8
      • Case 9
      • Case 10
      • Case 11
      • Case 12
      • Case 13
      • Case 14
      • Case 15
      • Case 16
      • Case 17
      • Case 18
      • Case 19
  • Interpreter