Your ECG is Normal
All the values on your ECG fall within normal limits for adults and require no further action.
Breakdown of Your ECG Values
Let me walk through each measurement and explain why they're normal:
PR Interval: 158 ms
- Normal range: 120-200 ms in adults 1
- Your value of 158 ms is well within the normal range
- This indicates normal conduction from the atria to the ventricles through the AV node
- First-degree AV block would only be diagnosed if the PR interval was ≥200 ms (or ≥300 ms for more significant prolongation) 1
QRS Duration: 85 ms
- Normal range: 69-109 ms in adults 2
- Your value of 85 ms is perfectly normal
- This indicates normal ventricular depolarization
- Bundle branch blocks would require QRS duration ≥120 ms 3
- Your narrow QRS complex rules out any intraventricular conduction disturbances
QT Interval: 384 ms and QTc: 393 ms
- Normal QTc range:
- Your QTc of 393 ms is well below the concerning threshold of 440 ms 5
- No risk of long QT syndrome: The upper limit of normal is 440 ms, and values become concerning when QTc exceeds 470 ms 5
- Risk for dangerous arrhythmias (torsades de pointes) typically occurs when QTc exceeds 500 ms 6
Clinical Significance
Your ECG shows:
- Normal sinus rhythm with appropriate conduction
- No evidence of conduction blocks
- No QT prolongation
- No risk factors for arrhythmias based on these intervals
No follow-up ECG or cardiac evaluation is needed based on these measurements alone unless you have symptoms such as palpitations, syncope, chest pain, or a family history of sudden cardiac death 5.
Important Context
The automated measurements on ECG machines are generally reliable for normal values like yours, though they can sometimes overestimate QTc prolongation when it's borderline 7. In your case, with a QTc of 393 ms, there's no ambiguity—this is definitively normal regardless of measurement method.