259.2 ð åèç
259.2.0.1 å¿ è â Systematic Approach
- Standardization
- Rate
- Rhythm
- Axis
- Intervals (PR, QRS, QTc)
- Waves
- Chambers
- Ischemia / injury / infarction
- Special (WPW, channelopathy, electrolytes, drugs)
259.2.0.2 å¿ è â Normal Values
- Rate 60-100
- PR 120-200 ms
- QRS < 100 ms
- QTc < 440 men / < 460 women
- Axis -30° to +90°
259.2.0.3 å¿ è â STEMI Criteria
- ⥠1 mm in ⥠2 contiguous leads OR
- ⥠2 mm V2-V3 men; ⥠1.5 mm V2-V3 women
259.2.0.4 å¿ è â MI Localization
| Leads | Region | Artery |
|---|---|---|
| V1-V4 | Anterior | LAD |
| V5-V6, I, aVL | Lateral | LCx / diagonal |
| II, III, aVF | Inferior | RCA (80%) or LCx (20%) |
| V4R | Right ventricle | Proximal RCA |
| Posterior (V1-V2 reciprocal) | Posterior | LCx / RCA |
259.2.0.5 å¿ è â Hypertrophy Criteria
- LVH: Sokolow-Lyon S(V1) + R(V5/V6) ⥠35 mm; or Cornell R(aVL) + S(V3) > 28 (M) / 20 (F)
- LAE: P > 120 ms or P mitrale (bifid II)
- RAE: P > 2.5 mm II (P pulmonale)
259.2.0.6 å¿ è â BBB
- RBBB: QRS > 120, rSRâ V1, slurred S in V6
- LBBB: QRS > 120, notched R V6, QS or rS V1
- LAFB: left axis -45° to -90°
- LPFB: right axis +90° to +180° (exclude RVH first)
259.2.0.7 å¿ è â AV Blocks
- 1°: PR > 200
- Mobitz I: progressive PR â dropped beat (benign)
- Mobitz II: constant PR + dropped beats (often need pacemaker)
- 3°: AV dissociation
259.2.0.8 å¿ è â WPW
- Short PR + delta wave + wide QRS (pre-excitation)
- Risk of SVT + AF with rapid conduction
- Avoid AV nodal blockers in AF + WPW
259.2.0.9 å¿ è â Hyperkalemia Progression
- Peaked T â flattened P â wide QRS â sine wave â asystole
259.2.0.10 å¿ è â Pericarditis
- Diffuse ST elevation (concave) + PR depression (most leads, except aVR + V1)
- vs STEMI: regional ST elevation + reciprocal changes
259.2.0.11 å¿ è â Pulmonary Embolism
- S1Q3T3 + sinus tachycardia + RBBB + RAD + T-wave inversion V1-V3
- Most common: sinus tachycardia alone
259.2.0.12 å¿ è â Long QT (Acquired)
- Drugs: macrolides, FQ, antifungals, TCAs, citalopram, methadone, ondansetron
- Electrolyte: hypoK, hypoMg, hypoCa
- Risk: torsades de pointes
- Treatment: stop drug + correct electrolytes + Mg IV for torsades