Understanding Heart Blocks: ECG Interpretation (Part 6)

💡 This video is the last lesson in a series about ECG and EKG rhythm interpretation.

💡 The video focuses on explaining different types of heart blocks and their manifestations on the ECG.

💡 Bundle branch blocks are discussed, including left and right bundle branch blocks, and their identification using the V lead on a monitor.

❗ Right bundle branch blocks can be caused by various factors like pulmonary hypertension and conduction system degeneration.

❗ To identify a right bundle branch block, check the last part of the QRS complex in the V1 lead for a positive deflection.

❗ Left bundle branch blocks can be caused by cardiomyopathy, coronary artery disease, and conduction system degeneration.

❗ To identify a left bundle branch block, check the last part of the QRS complex in the V1 lead for a negative deflection.

📚 This video explains the concept of heart blocks and focuses on AV blocks.

⚡️ AV blocks can be challenging to analyze but understanding the regularity of P waves and QRS complexes is crucial.

🔎 The first-degree AV block is characterized by a prolonged PR interval and regular P and R waves with a narrow QRS complex.

A second-degree heart block, known as Mobitz Type 1, involves a cyclical prolongation of the PR interval followed by a dropped QRS complex.

Causes of Mobitz Type 1 heart block include increased vagal tone, myocardial ischemia, and the effect of certain drugs like calcium channel blockers, beta blockers, or digoxin.

The ECG shows irregular QRS complexes and P waves, indicating the irregularity in conduction and signaling within the heart.

🔑 A second-degree AV block can be identified by a progressively longer PR interval until the signal is completely blocked.

💡 A winky block is a type of second-degree AV block characterized by the PR interval getting longer and longer until the signal is dropped.

📝 A Mobitz Type 2 block is another type of second-degree AV block where intermittent blocks occur below the AV node, potentially leading to irregular R waves.

⚡️ Second-degree heart block Mobitz type 2 has irregular P waves and wide QRS complexes, causing decreased cardiac output.

🛑 Third-degree AV block, or complete heart block, results in no impulse transmission from the AV node to the ventricles, leading to hemodynamic compromise.

🩺 Immediate intervention, typically pacing, is often required for third-degree AV block.

📚 Heart blocks are characterized by wide QRS complexes and irregular PR intervals.

💡 Each type of heart block has unique criteria for identification.

🔍 Repetition and practice are essential in learning to interpret ECG and EKG rhythms.