Electrocardiogram Interpretation Course

Lesson 1 • Action Potential Phases

Details the five phases of the ventricular action potential and their ionic basis. Connects each phase to specific ECG intervals and segments.

Lesson 2 • The Cardiac Conduction System

Traces the pathway of electrical impulses from the SA node to the Purkinje fibers. Links conduction anatomy to expected ECG deflections.

Lesson 3 • Cardiac Cell Electrical Properties

Covers resting membrane potential, depolarization, and repolarization in cardiac cells. Establishes the cellular basis for all ECG waveform interpretation.

Lesson 1 • Limb Lead Placement and Theory

Explains Einthoven's triangle, bipolar limb leads, and augmented unipolar leads. Accurate placement is prerequisite to valid axis and rhythm interpretation.

Lesson 2 • ECG Machine Basics and Settings

Covers paper speed, gain calibration, and filter settings on standard ECG machines. Correct settings prevent artifact and ensure accurate waveform measurement.

Lesson 3 • Precordial Lead Placement

Details V1–V6 anatomical landmarks and the cardiac regions each lead surveys. Misplacement causes false ST changes and missed infarct patterns.

Lesson 1 • PR Interval and AV Conduction

Measures PR interval from P onset to QRS onset as a marker of AV conduction time. Normal range forms the baseline for detecting heart block.

Lesson 2 • QRS Complex Analysis

Defines Q, R, and S wave nomenclature, duration, and amplitude in each lead group. Accurate QRS analysis is essential for bundle branch and infarct diagnosis.

Lesson 3 • P Wave Morphology and Measurement

Analyzes P wave duration, amplitude, and axis as markers of atrial depolarization. Establishes normal values used to detect atrial abnormalities later.

Lesson 4 • ST Segment and T Wave

Evaluates ST segment position relative to the isoelectric line and T wave polarity. These components are critical for ischemia and repolarization assessment.

Lesson 1 • P Wave to QRS Relationship

Evaluates whether every P wave is followed by a QRS and whether the PR interval is constant. This relationship defines sinus versus ectopic and blocked rhythms.

Lesson 2 • Systematic Rhythm Interpretation Steps

Introduces a structured five-step approach to rhythm strip analysis applied consistently. A systematic method reduces diagnostic errors and missed findings.

Lesson 3 • Heart Rate Calculation Methods

Teaches the 300-box, 1500-box, and 6-second strip methods for rate calculation. Each method suits different rhythm regularity and strip length scenarios.

Lesson 1 • Atrial Flutter and Fibrillation

Distinguishes atrial flutter's sawtooth pattern from atrial fibrillation's chaotic baseline using rate and regularity. Both carry stroke risk requiring clinical action.

Lesson 2 • Premature Atrial Complexes

Identifies PACs by early P wave morphology, compensatory pause type, and aberrant conduction. PACs are precursors to sustained atrial arrhythmias.

Lesson 3 • Junctional Rhythms

Identifies junctional escape, accelerated junctional, and junctional tachycardia by rate and retrograde P wave position. Junctional rhythms indicate AV node pacemaker dominance.

Lesson 4 • Sinus Node Rhythm Variants

Covers sinus bradycardia, tachycardia, arrhythmia, and sick sinus syndrome with diagnostic criteria. These are the most common rhythms encountered in clinical practice.

Lesson 1 • Premature Ventricular Complexes

Recognizes PVCs by wide bizarre QRS, full compensatory pause, and absence of preceding P wave. PVC patterns predict risk of sustained ventricular arrhythmia.

Lesson 2 • Ventricular Fibrillation and Asystole

Identifies VF's chaotic waveform and asystole's flat line as cardiac arrest rhythms requiring immediate action. Recognition speed directly impacts patient survival outcomes.

Lesson 3 • Bundle Branch Blocks

Diagnoses RBBB and LBBB using QRS duration and lead-specific morphology criteria. Bundle branch blocks alter ST-T interpretation and mask ischemia patterns.

Lesson 4 • Atrioventricular Heart Blocks

Classifies first-degree, second-degree Mobitz I and II, and third-degree AV block by PR and QRS patterns. Block degree determines urgency of pacing intervention.

Lesson 1 • Non-ST-Elevation ACS Patterns

Recognizes ST depression and T wave inversion patterns of NSTEMI and unstable angina. These subtler findings require clinical correlation with biomarkers and symptoms.

Lesson 2 • Infarct Age and Evolution

Tracks ECG changes from hyperacute through acute, subacute, and chronic infarct phases over time. Recognizing infarct age guides reperfusion eligibility and management strategy.

Lesson 3 • Ischemia Versus Injury Versus Infarction

Distinguishes T wave inversion as ischemia, ST elevation as injury, and Q waves as infarction on a pathophysiological continuum. Each stage requires a different clinical response.

Lesson 4 • STEMI Localization by Lead Group

Maps ST elevation patterns to anterior, inferior, lateral, and posterior infarct territories. Lead grouping identifies the culprit coronary artery for reperfusion targeting.

Lesson 1 • Long QT and Short QT Syndromes

Differentiates congenital and acquired long QT subtypes and identifies short QT syndrome by QTc thresholds. Both syndromes predispose to sudden cardiac death via ventricular arrhythmia.

Lesson 2 • Structural Heart Disease Patterns

Identifies ECG markers of left and right ventricular hypertrophy, atrial enlargement, and cardiomyopathy. Voltage and axis criteria reflect underlying structural remodeling.

Lesson 3 • Wolff-Parkinson-White Syndrome

Identifies delta waves, short PR, and wide QRS as markers of accessory pathway conduction in WPW. Recognizing WPW prevents dangerous use of AV-blocking agents.

Lesson 4 • Brugada Syndrome Patterns

Recognizes Type 1, 2, and 3 Brugada patterns in right precordial leads and their arrhythmia risk. Sodium channel dysfunction underlies this potentially lethal channelopathy.