What is the significance of a prominent positive T wave in leads V1 and V2 on an electrocardiogram (ECG)?

Prominent Positive T Wave in V1, V2: Clinical Significance

Prominent positive T waves in leads V1 and V2 are generally considered normal variants in most individuals, especially in athletes, and do not require further evaluation in the absence of other concerning clinical or ECG findings.

Normal Variants vs. Pathological Findings

• Prominent positive T waves in V1-V2 are often part of the normal spectrum of ECG findings, particularly in athletes and young individuals 1
• Early repolarization patterns with J-point elevation, concave ST-segment elevation, and peaked T waves are present in up to 45% of Caucasian athletes and 63-91% of Black athletes 1
• T-wave inversion (not positive T waves) beyond V1 in non-Black athletes is more concerning and may require further evaluation 2

Demographic Considerations

• Age is an important factor when interpreting T waves in precordial leads:
  • In adolescents under 16 years, T-wave patterns in anterior leads (including prominent T waves) are often normal "juvenile" patterns 1, 2
  • In Black athletes, repolarization variants with J-point elevation and convex ST-segment elevation in anterior leads (V1-V4) are considered normal 1

When to Consider Pathology

• Prominent positive T waves may be concerning in certain clinical contexts:
  • When they represent "hyperacute" T waves in the earliest phase of ST-segment elevation acute myocardial infarction 3
  • When they appear in lead aVR (not V1-V2), as positive T waves in aVR have been associated with increased risk of sudden cardiac death 4
  • When accompanied by other abnormal ECG findings such as ST depression, pathologic Q waves, or other repolarization abnormalities 1, 2

Evaluation Algorithm

1. Assess for other abnormal ECG findings that would require further investigation:

   • ST-segment depression ≥0.5 mm in two or more contiguous leads 1
   • Pathologic Q waves (Q/R ratio ≥0.25 or ≥40 ms in duration in two or more leads) 1
   • T-wave inversion ≥1 mm in depth in two or more contiguous leads (excluding leads aVR, III, and V1) 1

2. Consider clinical context:

   • In asymptomatic individuals with isolated prominent positive T waves in V1-V2, no further evaluation is typically needed 1, 2
   • In symptomatic patients or those with concerning clinical history (syncope, chest pain, family history of sudden cardiac death), further evaluation may be warranted 2

Differential Diagnosis When Prominent T Waves Are Concerning

• Early phase of ST-segment elevation myocardial infarction (hyperacute T waves) 3
• Hyperkalemia 3
• Left ventricular hypertrophy 3
• Posterior wall myocardial infarction (prominent R waves and positive T waves in V1-V2) 5

Important Caveats

• Do not confuse prominent positive T waves with T-wave inversion, which has different clinical implications 1, 2
• Prominent positive T waves in V1-V2 should not be confused with the Brugada pattern, which features ST-segment elevation with downsloping ST segment followed by negative T waves in V1-V3 1
• Higher T-wave amplitude has actually been associated with better prognosis in patients receiving thrombolytic therapy for acute myocardial infarction 6

In conclusion, prominent positive T waves in V1-V2 are generally considered normal variants, particularly in athletes and young individuals, and do not require further evaluation unless accompanied by other concerning clinical or ECG findings.