EKG Arrhythmias & Dysrhythmias 1 Flashcards
6 cards from real EKG certification Certification practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 EKG Arrhythmias & Dysrhythmias 1 flashcards as text
A rhythm strip shows a regular rhythm at 60 bpm with a PR interval of 0.28 seconds that remains constant throughout. QRS complexes are narrow. What is the most likely interpretation?
Answer: First-degree AV block
First-degree AV block is defined by a consistently prolonged PR interval (>0.20 seconds) with every P wave followed by a QRS complex and no dropped beats. The rhythm remains regular and the QRS is typically narrow.
A patient's EKG shows progressive lengthening of the PR interval over several beats, followed by a non-conducted P wave (dropped QRS), then the cycle repeats. Which dysrhythmia does this describe?
Answer: Second-degree AV block Type I (Wenckebach)
Mobitz Type I (Wenckebach) is characterized by progressively lengthening PR intervals until a P wave is not conducted and a QRS is dropped. The pattern then resets and repeats cyclically.
On a 12-lead EKG, a patient shows a short PR interval (<0.12 seconds) and a slurred upstroke at the beginning of the QRS complex (delta wave) with a widened QRS. The patient complains of palpitations. What is the most likely diagnosis?
Answer: Wolff-Parkinson-White (WPW) syndrome
Wolff-Parkinson-White syndrome presents with a short PR interval, delta wave (slurred initial QRS deflection), and widened QRS due to an accessory pathway (Bundle of Kent) bypassing the AV node and pre-exciting the ventricles.
You observe a rhythm strip with no discernible P waves, a regular ventricular rate of 38 bpm, and wide, bizarre QRS complexes. The patient is hemodynamically unstable. What rhythm is this?
Answer: Idioventricular rhythm
Idioventricular rhythm originates in the ventricles, producing wide and bizarre QRS complexes at a rate of 20–40 bpm. The absence of P waves and the slow ventricular escape rate distinguish it from junctional rhythms, which produce narrow QRS complexes.
A patient's rhythm strip shows a regular P-to-P interval and a regular R-to-R interval, but the PR intervals vary with no consistent relationship between P waves and QRS complexes. The ventricular rate is slower than the atrial rate. What is this rhythm?
Answer: Third-degree (complete) AV block
Third-degree (complete) AV block occurs when no atrial impulses conduct to the ventricles. The atria and ventricles beat independently (AV dissociation), resulting in regular but unrelated P waves and QRS complexes, with the ventricular rate slower than the atrial rate.
A patient presents with a sudden-onset regular tachycardia at 170 bpm. The EKG shows narrow QRS complexes and retrograde P waves buried in or just after the QRS. Vagal maneuvers terminate the rhythm abruptly. What is the most likely diagnosis?
Answer: Atrioventricular nodal reentrant tachycardia (AVNRT)
AVNRT is the most common paroxysmal supraventricular tachycardia (SVT). It results from a reentrant circuit within the AV node, producing a regular narrow-complex tachycardia with retrograde P waves very close to or hidden within the QRS. It characteristically terminates with vagal maneuvers or adenosine.