An ECG adventure for the curious

Learn to read the heart's
electrical story.

Cardiac rhythm interpretation isn't difficult - it's unfamiliar. The Cardiac Dance turns every rhythm into a place you can picture, walk through, and remember under exam pressure. Welcome to Rhythm City.

56
Animated rhythms
14
Chapters
115+
Practice questions
5
Step method
Live monitor
Normal Sinus Rhythm
72BPM
LEAD II 25 mm/s Sinus · The DJ Booth
RegularityRateP WavePR IntervalQRS DurationNarrow or WideCheck the patient first RegularityRateP WavePR IntervalQRS DurationNarrow or WideCheck the patient first
The Heart Mansion

The heart is a pump and a power grid.

Rhythm City is a memory palace. For centuries, people have remembered hard things by tying them to places they can walk through in the mind - so we gave the heart a venue with rooms. To be clear: your heart has no DJ booth and no loading dock. The rooms are strictly an analogy - handholds for your memory, nothing more.

The heart runs two systems. Four rooms handle the plumbing - they move the blood. Four rooms handle the electrical - they create and route the signal. Here is why that split matters more than anything else on this page: an ECG records the electrical system and nothing else. It never shows you the plumbing. So we tour all eight rooms once - then spend the entire book in the electrical four, because that is where every rhythm you will ever read is born.

The Plumbing Four rooms - moves the blood. Invisible to an ECG.
Right Atrium

The Entrance Lobby

Blood returning from the body checks in here.

Right Ventricle

The Loading Dock

Ships that blood out to the lungs for oxygen.

Left Atrium

The Green Room

Oxygen-rich blood waits backstage.

Left Ventricle

The Power Plant

The strongest chamber - drives blood to the whole body.

The Electrical Four rooms - fires the signal. This is all an ECG shows you. Where rhythm interpretation lives
SA Node

The DJ Booth

Sets the tempo. Every normal heartbeat starts here.

AV Node

The Stage Manager's Booth

Relays the signal downstairs, with a deliberate pause.

Bundle of His & Branches

The Main Cable

Carries the signal down and splits it left and right.

Purkinje Fibers

The Stage Lighting Grid

Lights up both ventricles at once for one clean squeeze.

Why it works

Built to make rhythms stick.

Reading, memorizing, and forgetting is the old way. This is a place you can walk through.

56 living rhythms

Every rhythm, block, paced pattern and artifact rendered as a live, scrolling cardiac monitor - the way you'll actually see them on the job.

One systematic method

The five-step rhythm check - Regularity, Rate, P Wave, PR Interval, QRS Duration - applied the same way to every strip, every time.

Test yourself relentlessly

115+ practice questions across all 14 chapters, plus a timed 20-question Victory Lap exam - every answer with the reasoning behind it.

A reference you'll keep

A searchable glossary and a rhythm library you can return to long after the exam - when the strips are messier and the stakes are real.

Memory hooks, not cramming

The Heart Mansion, the Rhythm City venue, songs and movements - memory techniques used by serious learners for centuries.

Built for the CRAT

Aligned to the rhythm interpretation knowledge tested on the Certified Rhythm Analysis Technician exam - and the clinical work that follows.

Your guides

You won't walk the venue alone.

Two guides lead the way - the voice of clinical wisdom, and the voice of the screen in front of you.

Cardiologist

Dr. Pulse

A cardiologist with a gift for stories that stick. Dr. Pulse explains the clinical "why" behind every rhythm - and tells you when to act and when to observe.

Heart monitor

RhythmBot

A sharp-witted heart monitor with a nose for rogue beats. RhythmBot keeps you honest, hands you the shortcuts, and never lets you skip a step.

How to use this site

Your path to certification readiness.

1

Walk the chapters in order

Each chapter builds on the last. Start in the DJ Booth and work room by room through every rhythm family.

2

Watch the rhythms move

See every rhythm as a live monitor tracing in the Rhythm Library. Recognition starts with seeing the real thing.

3

Test yourself, every chapter

Answer every quiz question before checking your work. Retrieving an answer is what locks it into long-term memory.

4

Run the Victory Lap

Take the full 20-question practice exam under timed conditions. Aim for 80% or higher before scheduling the real thing.

The five-step rhythm check

The most important tool in the book.

STEP 1
Regularity
Are the R-R intervals equal?
STEP 2
Rate
How many beats per minute?
STEP 3
P Wave
Is there a P before every QRS?
STEP 4
PR Interval
How long from P start to QRS start?
STEP 5
QRS Duration
How wide is the QRS complex?
Learn the method
The doors are open

The heart is the most reliable rhythm in the human body.

Once you learn to listen to it, you'll hear it everywhere. Start your tour of Rhythm City tonight.