| Flap 1 | Flap 2 |
| Atrial depolarization | P wave |
| Ventricular depolarization | QRS complex |
| Ventricular repolarization | T wave |
| identify age of infarct | ST -T |
| Early MI (or hyperacute) | elevated ST - T |
| Hallmark of MI | Q Wave |
| Chronic MI/days to weeks | Wider Deeper Q wave |
| Acute/hours post MI | elevated S-T |
| Sub-acute/hours to days post MI | elevated S-T, inverted T |
| Weeks to months post MI | Q still wide and deep |
| P:QRS 1:1 HR 140-250 | Paroxysmal Tachycardia |
| Many ill-defined P-waves | Atrial fibrillation |
| May result in CVA | Atrial fibrillation |
| Saw-tooth" waves | Atrial flutter |
| rapid uncoordinated ventricular contraction | Ventricular Fibrillation |
