Detect Cardiac Arrhythmia ECG Quiz

Leads II, III, and aVF visualize the inferior heart wall supplied by the right coronary artery.

PVCs arise prematurely from ventricles, producing wide, early QRS complexes.

AIVR originates in ventricular tissue but at slower, transient rates.

Escape rhythms activate when primary pacemakers fail, resulting in very slow heart rates.

Ventricular fibrillation causes no effective cardiac output and requires immediate defibrillation.

Antiarrhythmics suppress ventricular automaticity and stabilize myocardial conduction.

Unstable tachyarrhythmias require immediate electrical cardioversion to restore perfusion.

Adenosine terminates AV nodal reentry, making it first-line for PSVT.

PSVT conduction uses normal ventricular pathways, resulting in narrow QRS complexes.

Wide QRS complexes indicate ventricular origin or aberrant conduction.

Vagal maneuvers increase parasympathetic tone, while adenosine transiently blocks AV conduction.

PSVT originates above the ventricles, producing narrow complexes and very rapid rates.

DC cardioversion rapidly restores sinus rhythm in unstable atrial flutter patients.

Rate-control medications slow AV conduction, stabilizing ventricular response in atrial flutter.

Rhythm analysis follows a systematic approach to prevent missed findings. Evaluating P waves confirms atrial activity, QRS width identifies ventricular involvement, rhythm regularity assesses conduction stability, P–QRS relationship confirms AV conduction, and heart rate determines clinical severity.

Flutter waves create a saw-tooth ECG appearance, especially visible in inferior leads.

Atrial flutter involves a single reentrant atrial circuit, producing rapid but regular atrial depolarizations.

Cardioversion after prolonged AFib risks dislodging atrial thrombi, leading to stroke or systemic embolism.

Cardioversion and radiofrequency ablation restore organized atrial conduction without relying on medications.

AFib with RVR often causes palpitations, dyspnea, chest discomfort, and fatigue due to rapid ventricular rates and poor cardiac output.

Rate control in AFib with RVR prevents hemodynamic compromise. IV diltiazem or beta blockers slow AV nodal conduction effectively.

Atrial fibrillation lacks organized atrial depolarization, producing a chaotic baseline and unpredictable ventricular response, described as irregularly irregular.

Supraventricular arrhythmias arise from the atria or AV node, distinguishing them from ventricular-origin rhythms.

Sinus arrhythmia maintains a normal PR interval but varies with respiration, causing slight rhythm irregularity while remaining physiologically normal.

Ventricular rhythms originate outside the normal conduction system, causing slow cell-to-cell conduction and wide QRS complexes with absent P waves.

AV nodal rhythms suppress SA node activity, resulting in absent or hidden P waves. Ventricular depolarization follows normal pathways, keeping QRS complexes narrow.

Supraventricular rhythms originate above the ventricles, allowing atrial depolarization and visible P waves. Ventricular rhythms bypass atrial activation, eliminating P waves.

Lead II aligns closely with the heart’s electrical axis, producing upright P waves and clear QRS complexes. This makes it ideal for identifying rhythm patterns and conduction abnormalities.