Cardiac Rhythm Assessment & ECG Interpretation 2026 – 35 Questions & Answers | Atrial Fibrillation, PVCs, Heart Blocks, ECG Intervals & Cardiac Conduction | Nursing & Cardiac Monitoring

This document contains approximately 35 exam-style questions and verified answers covering the essential principles of cardiac rhythm assessment, electrocardiogram (ECG) interpretation, cardiac conduction physiology, dysrhythmia recognition, and cardiovascular monitoring. The material provides a structured review of normal electrical conduction, ECG waveform analysis, interval measurement, rhythm identification, and clinical implications of common cardiac arrhythmias. It serves as a valuable study resource for students preparing for nursing examinations, ECG competency assessments, telemetry certifications, cardiovascular technology courses, and allied health programs. The document begins with a detailed review of the cardiac conduction system, emphasizing the role of the sinoatrial (SA) node as the heart's primary pacemaker and explaining how cardiac myocytes generate and transmit electrical impulses through automaticity and conductivity. Students learn the physiological processes of depolarization and repolarization, the unique characteristics of cardiac muscle cells, and the mechanisms that allow the heart to function as a coordinated electrical and mechanical unit. The material also examines factors influencing cardiac output, including preload, afterload, contractility, and stroke volume. A substantial portion of the content focuses on ECG waveform and interval interpretation. Topics include the PR interval, QRS complex, ST segment, QT interval, ECG timing measurements, and the distinction between segments and intervals. Students learn how to calculate ECG durations using standard grid measurements, interpret conduction abnormalities, identify prolonged PR intervals, recognize myocardial ischemia and infarction through ST-segment changes, and understand the clinical significance of prolonged QT intervals associated with drug toxicity and dysrhythmias. These concepts are fundamental to accurate ECG analysis and rhythm recognition. The study guide also provides extensive coverage of common cardiac dysrhythmias, including sinus bradycardia, atrial fibrillation (AFib), premature ventricular contractions (PVCs), and first-degree atrioventricular (AV) block. Students review ECG characteristics, causes, risk factors, clinical manifestations, hemodynamic consequences, and treatment approaches for each rhythm. Particular emphasis is placed on recognizing irregularly irregular rhythms, absent P waves, ectopic ventricular activity, prolonged PR intervals, and symptoms associated with reduced cardiac output such as dizziness, hypotension, syncope, fatigue, and nausea. Additionally, the material explores important cardiac emergency interventions and rhythm-management devices, including automated external defibrillators (AEDs), pacemakers, implantable cardioverter-defibrillators (ICDs), cardioversion, and antiarrhythmic therapies. Students gain an understanding of when these interventions are indicated, how they restore normal cardiac conduction, and their role in managing life-threatening arrhythmias such as ventricular tachycardia and ventricular fibrillation. The integration of ECG interpretation with clinical management makes this resource particularly useful for both examination preparation and patient-care applications. The content closely aligns with major cardiovascular education references, including Dubin's Rapid Interpretation of EKG's, Marriott's Practical Electrocardiography, Garcia and Holtz's 12-Lead ECG: The Art of Interpretation, Hampton's The ECG Made Easy, and the American Heart Association (AHA) Basic Life Support (BLS) and Advanced Cardiovascular Life Support (ACLS) Guidelines. These references are widely used in nursing, cardiovascular technology, emergency medicine, and allied health education programs. This document is particularly valuable for students enrolled in Nursing (RN, BSN, ADN, LPN/LVN), Cardiovascular Technology, Electrocardiography (ECG/EKG), Paramedic Science, Emergency Medical Services (EMS), Respiratory Therapy, Critical Care Nursing, Medical Assisting, Health Sciences, and Cardiovascular Nursing courses. It is also highly beneficial for telemetry technicians, monitor technicians, emergency department personnel, ICU clinicians, ACLS candidates, and healthcare professionals seeking to strengthen their ECG interpretation, rhythm assessment, and cardiac monitoring skills. Keywords: cardiac rhythm assessment, ECG interpretation, EKG interpretation, cardiac conduction system, SA node, cardiac electrophysiology, depolarization, repolarization, PR interval, QRS complex, QT interval, ST segment, sinus bradycardia, atrial fibrillation, AFib, premature ventricular contractions, PVCs, first degree heart block, AV block, cardiac dysrhythmias, cardiac monitoring, telemetry nursing, electrocardiography, pacemaker, implantable cardioverter defibrillator, ICD, cardioversion, automated external defibrillator, AED, ACLS preparation