Explain me 10 common heart diseases with ECG changes and ECG images of those diseases

Reading File

Finding Sources

Searching Images

ECG electrocardiogram myocardial infarction STEMI changes

Finding Sources

Searching Images

atrial fibrillation ECG rhythm strip

Searching Images

ventricular tachycardia ECG wide QRS

Searching Images

complete heart block third degree AV block ECG

Searching Images

left bundle branch block LBBB ECG pattern

Searching Images

hypertrophic cardiomyopathy ECG left ventricular hypertrophy

Searching Images

Wolff-Parkinson-White WPW syndrome delta wave ECG

Searching Images

pericarditis ECG saddle-shaped ST elevation diffuse

Searching Images

pulmonary embolism ECG S1Q3T3 right heart strain

Searching Images

long QT syndrome QT prolongation torsades de pointes ECG

Here is a comprehensive guide to 10 common heart diseases with their ECG changes and images:

10 Common Heart Diseases: ECG Changes & Images

1. 🫀 ST-Elevation Myocardial Infarction (STEMI)

Pathophysiology: Complete occlusion of a coronary artery causing transmural (full-thickness) myocardial infarction.

ECG Changes:

Stage	Changes
Hyperacute (minutes)	Tall, peaked "hyperacute" T-waves
Acute	Convex ("tombstone") ST elevation ≥1 mm in ≥2 contiguous leads
Evolving	T-wave inversion, pathological Q waves (>40 ms wide, >¼ R height)
Old/chronic	Persistent Q waves, T-wave inversion

Localisation:

Anterior (LAD): V1–V4 ST elevation
Inferior (RCA): II, III, aVF ST elevation + reciprocal depression in I, aVL
Lateral (LCx): I, aVL, V5–V6

Anterior STEMI (LAD occlusion):

Anterior STEMI ECG showing tombstone ST elevation V2-V5

Inferior STEMI (RCA occlusion):

Inferior STEMI ECG showing ST elevation in II, III, aVF with reciprocal changes

2. 🫀 Atrial Fibrillation (AF)

Pathophysiology: Chaotic, disorganized atrial electrical activity from multiple re-entry circuits; most common sustained arrhythmia.

ECG Changes:

No P waves — replaced by irregular fibrillatory (f) waves (best seen in V1, II)
Irregularly irregular RR intervals (hallmark)
Narrow QRS complexes (unless aberrant conduction/WPW)
Ventricular rate typically 100–160 bpm if uncontrolled

Atrial fibrillation ECG showing absent P waves and irregularly irregular rhythm

3. 🫀 Ventricular Tachycardia (VT)

Pathophysiology: Rapid ventricular rhythm (≥3 beats, rate ≥100 bpm) originating below the Bundle of His, often from re-entry around scar tissue (post-MI, cardiomyopathy).

ECG Changes:

Wide QRS complex (>120 ms), bizarre morphology
Regular rapid rate (100–250 bpm)
AV dissociation (P waves independent of QRS)
Fusion beats and capture beats (pathognomonic)
Positive or negative QRS concordance across precordial leads
No visible P waves preceding QRS

Ventricular tachycardia ECG showing wide complex tachycardia with AV dissociation

4. 🫀 Complete (Third-Degree) AV Heart Block

Pathophysiology: Total failure of conduction from atria to ventricles; the ventricles are maintained by a slow escape rhythm (junctional or ventricular).

ECG Changes:

Complete AV dissociation — P waves and QRS complexes march independently
Regular P-P intervals (atrial rate ~60–100 bpm)
Regular RR intervals at a slower rate (ventricular escape 30–50 bpm)
Wide QRS if infra-Hisian escape; narrow if junctional
P waves may "march through" QRS complexes and T waves

Complete third-degree AV block ECG showing total AV dissociation

5. 🫀 Left Bundle Branch Block (LBBB)

Pathophysiology: Failure of conduction through the left bundle branch, causing delayed and abnormal LV depolarization. Can indicate underlying CAD, cardiomyopathy, or hypertension.

ECG Changes (William pattern):

QRS duration ≥120 ms
V1: Broad, deep rS or QS (predominantly negative)
V5, V6, I, aVL: Broad, notched monophasic R wave ("M" shape)
No septal Q waves in I, V5, V6
Discordant ST-T changes (ST/T opposite to main QRS deflection)
New LBBB may be a STEMI equivalent (Sgarbossa criteria)

LBBB ECG showing broad notched R waves laterally and deep S in V1

6. 🫀 Hypertrophic Cardiomyopathy (HCM)

Pathophysiology: Asymmetric left ventricular hypertrophy (especially septal), causing diastolic dysfunction and LVOT obstruction. Leading cause of sudden cardiac death in young athletes.

ECG Changes:

LVH voltage criteria (Sokolow-Lyon: S in V1 + R in V5/V6 ≥35 mm)
Deep, symmetric "giant" T-wave inversions in precordial leads (V2–V5) — classic in apical HCM (Yamaguchi syndrome)
Strain pattern: ST depression in lateral leads
Absence of septal Q waves in I, aVL, V5, V6 (abnormal septal depolarization)
Left axis deviation
Atrial fibrillation may be present

HCM ECG showing high voltage LVH and deep T-wave inversions in precordial leads

7. 🫀 Wolff-Parkinson-White (WPW) Syndrome

Pathophysiology: Congenital accessory conduction pathway (Bundle of Kent) bypasses the AV node, causing ventricular pre-excitation and tachyarrhythmias (AVRT, AF with rapid ventricular response — potentially fatal).

ECG Classic Triad:

Short PR interval (<120 ms) — bypassed AV node delay
Delta wave — slurred upstroke at the start of QRS
Wide QRS (>120 ms) — fusion of pre-excited and normal depolarization
Secondary ST-T wave changes (discordant)
Pseudo-infarction Q waves possible (mimics MI)

WPW syndrome ECG showing short PR interval, delta waves, and widened QRS

8. 🫀 Acute Pericarditis

Pathophysiology: Inflammation of the pericardium, classically from viral infection (Coxsackievirus, EBV), causing diffuse epicardial irritation.

ECG Changes (4 stages):

Stage	Features
Stage 1 (acute)	Diffuse concave ("saddle-shaped") ST elevation in most leads; PR depression (most leads); PR elevation in aVR
Stage 2	ST normalizes, T-waves flatten
Stage 3	Diffuse T-wave inversions
Stage 4	ECG normalizes

Key differentiators from STEMI:

ST elevation is diffuse (not in one vascular territory)
Concave (not convex) morphology
PR depression is specific to pericarditis
Spodick's sign: downsloping TP segment
No reciprocal changes (except aVR)

Acute pericarditis ECG showing diffuse saddle-shaped ST elevation and PR depression

9. 🫀 Pulmonary Embolism (PE)

Pathophysiology: Thrombus obstructing pulmonary vasculature → acute right heart strain → rightward shift of electrical axis → characteristic ECG findings.

ECG Changes:

Sinus tachycardia (most common, ~44% of cases)
S1Q3T3 pattern (classic): prominent S wave in lead I + Q wave in lead III + T-wave inversion in lead III
T-wave inversions in V1–V4 (right ventricular strain pattern)
Incomplete or complete RBBB
Right axis deviation
P pulmonale (peaked P waves) indicating right atrial strain
AF may occur

⚠️ Note: A normal ECG does not exclude PE. S1Q3T3 has low sensitivity (~20%) but is highly specific when present.

Pulmonary embolism ECG showing classic S1Q3T3 pattern with right heart strain

10. 🫀 Long QT Syndrome (LQTS)

Pathophysiology: Prolonged ventricular repolarization (congenital ion channel mutations — KCNQ1, KCNH2, SCN5A — or acquired from drugs/electrolytes), predisposing to life-threatening Torsades de Pointes (TdP) and sudden cardiac death.

ECG Changes:

Prolonged QTc interval (corrected for rate using Bazett's formula)
- Normal: men <440 ms, women <460 ms
- Borderline: 440–500 ms
- High risk: >500 ms
Broad, prominent T waves (LQTS type 1) or bifid T waves with a "hump" (LQTS type 2) or prominent U waves (LQTS type 3)
Torsades de Pointes: polymorphic VT with twisting QRS complexes around the isoelectric line — "R on T" initiation pattern

Long QT syndrome ECG showing QT prolongation leading to Torsades de Pointes

Quick Reference Summary Table

#	Disease	Key ECG Finding
1	STEMI	Convex ST elevation + Q waves in territory
2	Atrial Fibrillation	No P waves, irregularly irregular RR
3	Ventricular Tachycardia	Wide QRS tachycardia, AV dissociation
4	Complete Heart Block	P & QRS march independently (AV dissociation)
5	LBBB	Wide QRS, monophasic R in V5-V6, rS in V1
6	HCM	LVH + giant T-wave inversions (V2-V5)
7	WPW	Short PR + delta wave + wide QRS
8	Pericarditis	Diffuse concave ST elevation + PR depression
9	Pulmonary Embolism	S1Q3T3 + sinus tachycardia + RV strain
10	Long QT Syndrome	QTc >500 ms + Torsades de Pointes

Clinical pearl: ECG interpretation is always contextual — the same ECG finding can mean different things depending on the clinical scenario (e.g., new LBBB + chest pain = possible STEMI equivalent; diffuse ST elevation + fever + pleuritic chest pain = pericarditis, not MI).

Create a quick reference PDF guide of these 10 heart diseases and their ECG patterns

Reading File

Running Command

Writing File

Running Command

Your credits are exhausted. Your daily credits reset tomorrow, or you can purchase a top-up for more.

Download the ECG reference PDF from workspace

Your credits are exhausted. Your daily credits reset tomorrow, or you can purchase a top-up for more.

This is a shared conversation. Sign in to Orris to start your own chat.