Interpret the ECG findings: sinus rhythm, heart rate 92 bpm, PR interval 164 ms, QRS duration 78 ms, QTc 431 ms, PQRS/T intervals 45/44/42 ms, and RV5/SV1 amplitude ratios 0.614/0.453. | Rounds Interpret the ECG findings: sinus rhythm, heart rate 92 bpm, PR interval 164 ms, QRS duration 78 ms, QTc 431 ms, PQRS/T intervals 45/44/42 ms, and RV5/SV1 amplitude ratios 0.614/0.453. | Rounds
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Interpret the ECG findings: sinus rhythm, heart rate 92 bpm, PR interval 164 ms, QRS duration 78 ms, QTc 431 ms, PQRS/T intervals 45/44/42 ms, and RV5/SV1 amplitude ratios 0.614/0.453.

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ECG Intervals and Rhythm Overview

Sinus rhythm is present with a ventricular rate of 92 bpm, and atrioventricular conduction is within expected limits based on the PR interval. [1] The QRS duration is normal at 78 ms. [2] The corrected QT interval (QTc) is 431 ms, which is not prolonged by standard QTc thresholds used to define prolonged QT. [3]

Heart Rate and Sinus Rhythm

A heart rate of 92 bpm with sinus rhythm indicates a normal rhythm origin at the sinoatrial node. [1]

Atrioventricular Conduction (PR Interval)

The PR interval of 164 ms is within the usual adult reference range of approximately 120 to 200 ms. [4] No first-degree atrioventricular block is indicated by the PR interval length. [4]

Ventricular Conduction (QRS Duration)

The QRS duration of 78 ms is normal because it is <120 ms. [2]

Repolarization (QTc Interval)

The QTc of 431 ms is below commonly used prolonged QT thresholds (460 ms in women and 450 ms in men) in standard interpretation guidance. [3] This value therefore does not meet criteria for QTc prolongation. [3]

Additional Interval Fields Provided

The reported “PQRS/T intervals 45/44/42 ms” and “RV5/SV1 amplitude ratios 0.614/0.453” require the exact ECG measurement definitions and lead placement/context to map to a specific clinical criterion. Clinical interpretation should rely on the printed ECG with waveform morphology, measured QT (not only device-derived QTc), and the machine’s diagnostic statements. [3]

Clinical Correlation and Safety Checks

Medication review for QT-prolonging agents and electrolyte assessment (potassium, magnesium, and calcium) are appropriate when QTc is being evaluated. [3] Repeat ECG with consistent measurement conditions is appropriate when QTc is near decision thresholds or when the clinical context changes. [3]

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