EKG

Sgarbossa Criteria

1. ST elevation ≥ 1 mm concordant with QRS complex (most predictive of AMI of the 3 criteria)

2. ST depression ≥ 1 mm in lead V1, V2, or V3

3. ST elevation ≥ 5 mm where discordant with QRS complex

Modified 3rd rule: ST elevation ≥ 0.25 x S-wave (Ann Emerg Med. 2012 Dec;60(6):766-76)

Left Ventricular Hypertrophy

The Sokolow-Lyon index:

• S in V₁ + R in V₅ or V₆ (whichever is larger) ≥ 35 mm
• R in aVL ≥ 11 mm

The Cornell voltage criteria:

• S in V₃ + R in aVL > 28 mm (men)
• S in V₃ + R in aVL > 20 mm (women)

Romhilt-Estes point score system ("diagnostic" >5 points; "probable" 4 points):

Other voltage-based criteria for LVH include:

• Lead I: R wave > 14 mm
• Lead aVR: S wave > 15 mm
• Lead aVL: R wave > 12 mm
• Lead aVF: R wave > 21 mm
• Lead V₅: R wave > 26 mm
• Lead V₆: R wave > 20 mm

Echo: normal LV myocardial thickness (end-diastole) 0.6-1.1cm

ECG animation: http://www.cardioohrid.org.mk/userfiles/Flash/0038a.swf

SVT vs. VT (from LITFL)

Practice EKG Interpretation: http://ecg.bidmc.harvard.edu/maven/mavenmain.asp

Lewis Lead for atrial activity: http://emcrit.org/wee/lewis-lead/