Basic Cardiac Rhythm Interpretation 2026 – 70 Questions & Answers | ECG Interpretation, Arrhythmias, AV Blocks, Electrolyte Imbalances & Antiarrhythmic Drugs | Nursing & Cardiac Monitoring

This document contains approximately 70 comprehensive exam questions and verified answers covering the essential principles of electrocardiogram (ECG/EKG) interpretation, cardiac conduction, dysrhythmia recognition, electrolyte abnormalities, and antiarrhythmic pharmacology. The material provides a detailed review of cardiac electrophysiology and rhythm analysis, making it an excellent study resource for students preparing for ECG examinations, telemetry certifications, nursing assessments, cardiac monitoring courses, Advanced Cardiovascular Life Support (ACLS) preparation, and allied health examinations. The document begins with the foundations of cardiac rhythm interpretation by examining the components of a normal ECG tracing, including the P wave, PR interval, QRS complex, ST segment, T wave, QT interval, and R-R interval. Students learn how each waveform corresponds to cardiac electrical activity, how to measure intervals accurately, and how abnormalities in conduction and repolarization can indicate underlying cardiac pathology. The material also introduces the Eight Steps of ECG Interpretation, providing a systematic framework for evaluating heart rate, rhythm regularity, atrial activity, ventricular conduction, and overall rhythm diagnosis. A substantial portion of the content focuses on identifying and differentiating common cardiac arrhythmias and conduction disorders. Topics include sinus bradycardia, sinus tachycardia, premature atrial contractions (PACs), supraventricular tachycardia (SVT), atrial flutter, atrial fibrillation, junctional dysrhythmias, premature ventricular contractions (PVCs), ventricular tachycardia (V-Tach), ventricular fibrillation (V-Fib), and asystole. The material emphasizes recognition of hallmark ECG findings, rhythm regularity, rate characteristics, P-wave morphology, QRS duration, and clinical significance, all of which are essential competencies in emergency medicine, telemetry monitoring, and critical care practice. The study guide also provides extensive coverage of atrioventricular (AV) conduction abnormalities, including First-Degree AV Block, Second-Degree AV Block Type I (Mobitz I/Wenckebach), Second-Degree AV Block Type II (Mobitz II), Third-Degree (Complete) Heart Block, and Bundle Branch Blocks. Students learn to identify PR interval prolongation, dropped beats, AV dissociation, widened QRS complexes, and conduction delays that frequently appear on licensing examinations and clinical competency assessments. These concepts are particularly important for nurses, paramedics, monitor technicians, and cardiovascular professionals involved in patient monitoring and rhythm interpretation. Additionally, the material explores the relationship between electrolyte imbalances and ECG changes, including hypokalemia, hyperkalemia, hypocalcemia, hypercalcemia, hypomagnesemia, and hypermagnesemia. The document explains how electrolyte disturbances alter cardiac conduction, repolarization, myocardial excitability, and rhythm stability, while highlighting associated ECG manifestations such as peaked T waves, prolonged QT intervals, widened QRS complexes, U waves, ST-segment abnormalities, and life-threatening dysrhythmias. These topics are critical for understanding clinical decision-making in emergency, cardiac, and intensive care settings. The resource further examines antiarrhythmic pharmacology, including Vaughan-Williams Class I (A, B, and C) sodium channel blockers, Class II beta blockers, Class III potassium channel blockers, and Class IV calcium channel blockers. Students review mechanisms of action, representative medications, electrophysiologic effects, conduction changes, and therapeutic applications in the management of atrial and ventricular dysrhythmias. This integration of rhythm interpretation and pharmacologic management provides a comprehensive understanding of modern arrhythmia treatment strategies. The content closely aligns with leading cardiovascular and electrocardiography references, including Dubin's Rapid Interpretation of EKG's, Garcia and Holtz's 12-Lead ECG: The Art of Interpretation, Hampton's The ECG Made Easy, Marriott's Practical Electrocardiography, and the American Heart Association (AHA) ACLS Provider Manual. These texts are widely utilized in nursing education, cardiovascular technology programs, emergency medicine training, telemetry certification courses, and advanced cardiac life support instruction. This document is particularly valuable for students enrolled in Nursing (RN, BSN, LPN), Paramedic Science, Emergency Medical Services (EMS), Cardiovascular Technology, Respiratory Therapy, Critical Care Nursing, Health Sciences, Medical Assisting, Electrocardiography (ECG/EKG), and Cardiovascular Nursing courses. It is also highly beneficial for telemetry technicians, emergency department personnel, ICU clinicians, cardiac monitor technicians, ACLS candidates, cardiovascular technologists, and healthcare professionals seeking to strengthen their ECG interpretation and arrhythmia recognition skills. Keywords: basic cardiac rhythm interpretation, ECG interpretation, EKG interpretation, cardiac arrhythmias, cardiac dysrhythmias, electrocardiography, sinus bradycardia, sinus tachycardia, atrial fibrillation, atrial flutter, supraventricular tachycardia, junctional rhythm, premature atrial contractions, premature ventricular contractions, ventricular tachycardia, ventricular fibrillation, asystole, AV block, Mobitz I, Mobitz II, complete heart block, bundle branch block, electrolyte imbalances, hyperkalemia, hypokalemia, antiarrhythmic drugs, ACLS, telemetry monitoring, cardiac conduction, nursing exam prep