Question

identify this rhythm

junctional rhythm
sinus bradycardia
sinus rhythm with a 2nd degree block
normal sinus

Explanation:

Analyze the ECG strip characteristics

• P waves: Present, upright, and preceding QRS complexes, but there is a non-conducted P wave (a P wave not followed by a QRS complex) visible in the middle of the strip (around the 13th-14th large box).
• PR interval: The PR interval of conducted beats remains constant.
• QRS complexes: Narrow, but occasionally dropped.
• Rhythm: Irregular due to the dropped QRS complex.

Identify the specific arrhythmia

• The presence of a non-conducted P wave (dropped QRS) with constant PR intervals in the conducted beats is characteristic of a Second-Degree AV Block (specifically Mobitz Type II).
• This matches the option "Sinus Rhythm with a 2nd degree block".

Exclude other options

• Junctional Rhythm: Characterized by absent or inverted P waves and typically a regular rate of 40–60 bpm.
• Sinus Bradycardia: Regular rhythm with a rate < 60 bpm, where every P wave is conducted.
• Normal Sinus: Regular rhythm, rate 60–100 bpm, with 1:1 AV conduction.

Answer:

• Junctional Rhythm
• Sinus Bradycardia
• Sinus Rhythm with a 2nd degree block (Correct answer)
• Normal Sinus