Overview of First and Second-Degree Atrioventricular (AV) Block Core Characteristics · 1st-Degree: Fixed PR >200ms; 1:1 conduction. · Mobitz I: PR lengthens → QRS drop. · Mobitz II: Fixed PR; sudden QRS drop. Clinical Significance · 1st-Degree & Mobitz I: Often benign; monitor. · Mobitz II: Infranodal; high-risk for progression → pacemaker assessment. #AVBlock #HeartBlock #Cardiology #ECG #EKG #MedEd #MedicalEducation #CardioEd #HeartRhythm #Wenckebach #Mobitz | Abdallah Othman

A First-Degree AV Block is characterized by a prolonged conduction time through the AV node, resulting in a PR interval greater than 0.20 seconds. Every P wave is still followed by a QRS complex, meaning no beats are actually dropped—it's just a delay. ​Key ECG Finding: PR Interval > 0.20 seconds (or > 5 small boxes) ​Significance: Usually asymptomatic and benign, but important to monitor as it can sometimes progress to a higher-grade block. ​#EKG #ECG #heartblockage #HeartBlock #cardiology | Ho

First Degree AV Block - EKG (ECG) Interpretation