The ECG image given below represent

DSSSB 6 September 2024

Medical Surgical Nursing

Medium

Appeared in: DSSSB 6 September 2024

Explanation

The ECG shows a premature beat that interrupts the underlying normal sinus rhythm.
The QRS complex of this premature beat is wide (greater than 0.12 seconds) and has a bizarre morphology, which is the hallmark of a ventricular origin.
There is no P wave preceding the wide complex, confirming the impulse did not originate in the atria.
A full compensatory pause follows the beat, which is characteristic of a PVC.
These features collectively identify the arrhythmia as Premature Ventricular Contractions.

Option A: Premature atrial contractions (PACs) originate in the atria and are characterized by a premature P wave followed by a narrow QRS complex. The image shows a wide QRS complex with no preceding P wave.
Option B: Atrial fibrillation is an irregularly irregular rhythm with no discernible P waves and a chaotic baseline. The ECG in the image shows a regular underlying rhythm with clear P waves for the normal beats.
Option C: Atrial flutter is characterized by distinctive 'sawtooth' flutter waves in place of P waves. The baseline in the provided ECG is flat between the normal complexes, with no sawtooth pattern.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain ECG interpretation of ventricular arrhythmias as background academic context rather than a clinical decision trigger.
While isolated PVCs are common and often benign in healthy individuals, frequent PVCs can be a sign of underlying heart disease, ischemia, or electrolyte imbalances (hypokalemia, hypomagnesemia).
Nurses must assess the patient's clinical status, not just the monitor. Check for symptoms like palpitations, chest pain, or dizziness, as frequent PVCs can decrease cardiac output and blood pressure.
It is critical to report the frequency and pattern of PVCs. Runs of three or more consecutive PVCs constitute ventricular tachycardia (VT), a life-threatening arrhythmia requiring immediate intervention.

How to Approach the Question

First, analyze the overall rhythm. Look at the R-R intervals of the normal-looking beats to determine if the underlying rhythm is regular or irregular.
Next, identify the components of the normal beats: find the P wave, measure the PR interval, and measure the QRS duration (narrow or wide). This establishes the baseline rhythm (in this case, normal sinus rhythm).
Scan the strip for any beats that look different or occur early. In this image, one beat clearly stands out.
Analyze the abnormal beat: Is it early? Is there a P wave before it? Is the QRS complex narrow or wide and bizarre?
Synthesize the findings: An early beat with no P wave and a wide, bizarre QRS complex is the classic presentation of a Premature Ventricular Contraction (PVC).
Compare these findings to the definitions of the other options (PAC, A-fib, A-flutter) to confirm they do not match.

Concept Tested & Keywords

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