Pathological q Waves

   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