• Action Potential and Repolarization
• Benign Early Repolarization
• ECG and Benign Early Repolarization
• J-Point and Concave ST Elevations
• Variants of Benign Early Repolarization
• Benign Early Repolarization vs. Pericarditis
• ST/T Ratio (V6)
• Inferolateral Early Repolarization
• Malignant Ventricular Arrhythmia

Action Potential and Repolarization

• Action Potential
• Spreads in the myocardial wall from endocardium to epicardium
• The action potential curve has a different shape in the endocardium and epicardium
• Due to the different properties of ion channels
• Ventricular Depolarization (Phase 0)
• Creates the QRS complex on the ECG
• Ventricular Repolarization (Phase 1)
• Begins on the ECG as the ST segment
• Phase 1 is the beginning of repolarization
• Often referred to as early repolarization

ECG and Benign Early Repolarization

• Elevation of the J-point in at least 2 adjacent leads
• Most commonly in precordial leads (V2-6)
• The J-point connects the QRS and ST segment
• J wave in precordial leads
• At the end of the QRS complex J wave
• Concave ST elevations over the entire heart, but mainly precordial (V2-V6)
  • Most commonly up to 2mm in precordial leads, and up to 0.5mm in limb leads
  • Size depends on heart rate
  • Increases with bradycardia
  • Disappears with tachycardia
• Tall, peaked T waves over the entire heart, but mainly precordial (V2-V6)
• ST/T ratio (V6) < 0.25
• ST depression may be present (aVR)
  
  
• Benign Early Repolarization (BER) is not found in patients over 50 years old

Variants of Benign Early Repolarization

• BER can have the following 4 variants
• Typically seen in 2 adjacent leads, most commonly in precordial leads (V2-6)
• The first 2 variants are the most common
• The second 2 variants without ST elevation are very rare

Most Common BER Variants

Very Rare BER Variants

Benign Early Repolarization vs. Pericarditis

• Benign Early Repolarization (BSR) and pericarditis both present with concave ST elevations
• Differential diagnosis is made using additional ECG features

Pericarditis

• ST elevations are in all leads (except aVR, V1)
• PQ depressions are in all leads (except aVR, V1)
• ST/T ratio (V6) > 0.25
• No fish hook pattern (V4)
• Normal T wave amplitude
• ECG changes gradually resolve (approx. within 4 weeks)

Benign Early Repolarization

• ST elevations are in the precordial leads (V2-V6)
• Without PQ depressions
• ST/T ratio (V6) < 0.25
• Fish hook pattern (V4)
• High amplitude T waves (T waves are symmetric)
• ECG changes persist for years (do not resolve within 4 weeks)

Inferolateral Early Repolarization

• Benign Early Repolarization
  • is considered a benign diagnosis (a variant of normal)
  • If changes are observed only in the precordial leads (V2-V6)
    
    
• Inferolateral Early Repolarization
• Typically features a notch at the end of the QRS complex, found in at least two leads:
• Inferior leads (II, III, aVF)
• Lateral leads (I, aVL, V4-6)
• According to some studies, it has a potentially increased risk:
• Ventricular Fibrillation
• Sudden Cardiac Death

Benign Early Repolarization

• Concave ST elevations in precordial leads (V1-V6) and I
• Pericarditis has ST elevations in all leads except (aVR, V1)
• Fish-hook pattern (V3, V4, III)
• Pericarditis does not have this fish-hook pattern
• ST/T = 0.16
• This indicates benign early repolarization
• The patient has benign early repolarization

Benign Early Repolarization

• Concave ST elevations in almost all leads
• Precordial (V2-V6) and inferolateral (I, II, III, aVF)
• Fish-hook pattern (II, III, aVF)
• High, peaked T waves (V2-V5, II)
• ST/T = 0.16
• This indicates benign early repolarization

Benign Early Repolarization, Heart Rate 76/min

• This is the same patient as on the previous ECG
• Sinus Rhythm (76/min)
• The ECG no longer shows sinus bradycardia
• Signs of benign early repolarization disappear with increasing heart rate
• Concave ST elevations have decreased
• Fish-hook pattern has disappeared
• This ECG does not show typical signs of BSR
• These signs were present in the previous ECG with bradycardia

Acute Pericarditis

• Concave ST elevations and PQ depressions in all leads except (aVR)
• Benign early repolarization (BSR) does not have PQ depressions
• No fish-hook pattern in precordial leads
• ST/T = 0.33
• Indicating pericarditis
• Patient has pericarditis (stage 1)