2 ECG Interpretation Fundamentals Free Online FlashCards

What are standard ECG paper speed and gain?

A standard 12-lead ECG is usually recorded at 25 mm/s with a gain of 10 mm/mV.

How do you estimate rate in an irregular rhythm?

Count the QRS complexes in a 6-second strip and multiply by 10 to estimate average ventricular rate.

What pattern typically supports sinus rhythm?

Sinus rhythm typically has consistent P waves before each QRS, a stable PR interval, and a regular rhythm.

How is the PR interval measured, and what is its common adult range?

Measure the PR interval from the start of the P wave to the start of the QRS. A common adult reference range is 0.12–0.20 s.

What can a prolonged PR interval indicate?

A prolonged PR interval indicates delayed atrioventricular conduction.

What is the systematic sequence for reading an ECG?

After confirming patient details, tracing quality, calibration, and lead placement, assess rate, rhythm, intervals, waveforms and segments, compare prior ECGs, then summarize findings.

How should ECG interpretation guide emergency care?

Interpret the ECG alongside the patient's symptoms and condition; do not let interpretation delay immediate assessment or treatment.

At standard speed, how much time does one small box represent?

At 25 mm/s, one small horizontal box represents 0.04 s.

At standard speed, how much time does one large box represent?

At 25 mm/s, one large horizontal box represents 0.20 s.

What three patterns describe QRS regularity?

Classify QRS regularity as regular, regularly irregular, or irregularly irregular.

How is QRS duration measured, and what is its usual adult reference?

Measure QRS duration from the start to the end of the QRS complex. It is usually less than 0.12 s in adults.

What does the QT interval span, and why consider QTc?

The QT interval runs from the start of the QRS to the end of the T wave. Because it varies with heart rate, clinicians commonly consider QTc.