New 10/27/2026
Sinus Creek is out on Google Play!!
It's official. Version 1.0 is live on Android today. I built it after re-memorizing every EKG rhythm for BLS and ACLS, strip after strip after strip. Now you paddle up the rhythm and name it. Later rivers, you treat the patient creek.
iPhone is coming soon. Don't want to wait? Play it in your browser right now. Come paddle!
Sinus Creek
Learn to read a heart rhythm by canoeing down one.
The creek runs at you. Every wall of whitewater is one heartbeat. Rate is how often the water hits you, and regularity is whether you can trust the next one.
By the end, a strip across a monitor looks like a creek you already know.
Every stretch ends at a fork with a hand painted sign over each mouth. Whichever mouth you are in when the fork arrives is your answer. So naming a rhythm is steering, not tapping.
A wrong read scrapes the boat and goes in the log. It never costs you a life, and it never wipes your river.
Written by a nurse, for the people who have to read the monitor at three in the morning: nursing students, nurses, paramedics and med students.
Free while in beta No account, no email Plays offline once installed One thumb, portrait
Swipe for more →
Screenshots
What it looks like
Six screens off a real build, captured by the game's own script.
What you will learn
22 rhythms, 11 findings, and which hand goes where.
33 things to learn, and every one can be told apart by what the water shows. 29 are answered by name at a fork. The other 4 are the arrests, and you answer those with your hands.
Starting Creek
19 pools
Run the water and name it
One new rhythm at a time, paired with the one it gets confused with, and a cumulative pool every fifth rung. Mobitz I lands next to Mobitz II on purpose.
The Narrows
19 pools
What you do about it
The same water, now asking what you do about it. Thirteen answers, from watch and reassess to compressions and epi. Stability is part of the question: A-fib with RVR in a talking patient wants rate control, and the same strip in a patient who is grey and cold wants electricity.
The Braids
12 pools
The water off the main channel
Where the river splits. Paced rhythms, escape rhythms, PVCs, and pulseless electrical activity. A paced rhythm and a rhythm with no pulse can look alike on the strip, and only one of them is keeping anyone alive. The boat is the tell.
Deep Water
15 pools
Shape, not timing
Everything upstream is timing. This is the findings, and shape is the thing you cannot get from counting.
The Endless Voyage
3 endless runs
How far can you get
Endless, in three tiers. Low water is gentle and has no end to it. High water answers back, and a wrong call changes the water under you. Flood is everything the river has, and it will get you eventually.
These are not five separate campaigns. All 68 stops interleave into one route, so you meet a rhythm in Starting Creek before The Narrows ever asks you to treat it, and a pool never announces what is in it.
Every rhythm in the creek
Sinus
- Normal Sinus Rhythm
- Sinus Bradycardia
- Sinus Tachycardia
Atrial
- Supraventricular Tachycardia
- Atrial Fibrillation
- Atrial Fibrillation with RVR
- Atrial Flutter
Junctional
- Atrial Escape Rhythm
- Junctional Escape Rhythm
The blocks
- First Degree AV Block
- Second Degree AV Block, Type I (Wenckebach)
- Second Degree AV Block, Type II (Mobitz)
- Third Degree (Complete) Heart Block
Wide and ventricular
- Sinus Rhythm with PVCs
- Ventricular Tachycardia
- Idioventricular Rhythm
- Accelerated Idioventricular Rhythm (AIVR)
Paced
- Ventricular Paced Rhythm
The four you answer with your hands
- Torsades de Pointes
- Ventricular Fibrillation
- Asystole
- Pulseless Electrical Activity
And 11 findings, which are shape rather than timing
- ST Elevation (STEMI)
- ST Depression
- T Wave Inversion
- Left Bundle Branch Block
- Right Bundle Branch Block
- Left Ventricular Hypertrophy
- Right Ventricular Hypertrophy
- Hyperkalemia
- Hypokalemia
- Hypocalcemia
- Hypercalcemia
Thirteen things the water actually shows you
rate, regularity, dropped beats, premature beats, QRS width, P wave behaviour, PR interval, flutter waves, AV dissociation, the ST segment, the T wave, the QT interval, and QRS amplitude by side. Every rhythm carries a range of speeds, not one number.
How you play it
Push off
The route. 65 pools and 3 endless runs across the 5 creeks, interleaved into one order, picking up wherever you left it.
Daily Rapids
One stretch of water a day. Finishing it extends a streak, and a capsize does not break one.
Four arrests a run
No pulse and a clock. Alternating strokes are compressions, a held thumb charges, letting go delivers the shock. Every seven seconds the creek calls a rhythm check.
The library
All 33 entries, filled in by playing. Water you have never met has no door, and the criteria open only after you have read that rhythm right at a fork once.
It teaches rhythms, not 12-lead reading, so pair it with real 12-lead practice.
Free now, $5 later
It is free while in beta. After it goes to the App Store, the first few pools will be free and the entire game will be $5. No subscription and no advertising.
There is no account. No login, no email, no password. Your river is kept on your device, and it is never reset.
It works with no signal. Install it once and it runs in a basement or a hospital stairwell.
It sends back an anonymous record of how a run went, and you can turn it off in Settings. The privacy page says what is in it.
It bends to you. Settings has switches for sound, calm water, bold signs, a left thumb, bigger text and captions.
Sinus Creek is a teaching game. It is not a monitor, it is not a diagnostic tool, and it is not medical advice. It deliberately contains no drug doses. Nothing in it should be used to make a decision about a real patient. Made by OxidativeRN in partnership with Data Divers LLC.