--- title: Casualties Unknown Stroke, Cardiac Arrest and Heart Guide description: What causes strokes, fibrillation and cardiac arrest, and what actually treats them. url: https://casualtieswiki.wiki/health/heart-and-stroke/ --- Health # Casualties Unknown heart and stroke guide How a heart problem usually escalates - 1 **Stress or stimulants raise heart rate and pressure**Pain, drugs, a sense of impending doom - 2 **Hypertensive crisis**A chance of stroke every second - 3 **Fibrillation**Rises quickly above 280 bpm - 4 **Cardiac arrest**The heart stops; act immediately - 5 **Treat**Defibrillator, amiodarone, or CPR in co-op _Built from official patch notes for versions 6.0 to 7.0. Thresholds are from those notes; exact values may have changed in the full game._ **Short answer:** in Casualties Unknown, stroke comes from very high blood pressure, and cardiac arrest from fibrillation or a failing heart. Lower your pressure with sodium nitroprusside and remove the stress causing it. Treat a stroke with Braingrow. For cardiac arrest, use a defibrillator, knowing that it often fails. reported Version 6.0 rebuilt the whole cardiovascular system “with many more variables and possible effects”. confirmed Many older guides predate that, so check the date of anything you read about heart mechanics. ## What does the Casualties Unknown heart system track? The health panel shows heart rate, blood pressure and oxygen together. An official screenshot shows a line reading 129 with 155/102 next to 100% O2, above an ECG trace. confirmed Blood volume sits above it, along with the rate of loss. If you play unchipped you do not see these numbers, and have to judge from symptoms. ## What causes a stroke in Casualties Unknown? A stroke risk appears at a **hypertensive crisis**. The 6.1 notes changed the stroke chance at that point from 5% per second to **2% per second**. confirmed Common causes reported by players: - The **sense of impending doom** moodle, which spikes adrenaline when an elder thornback hunts you. reported - Stimulant drugs and overdoses. - Exertion while already under stress. Recordings show players panicking about strokes because there are few cures. One player says plainly that a stroke will kill you unless you have Braingrow. confirmed ## How do you treat a stroke? Braingrow is the usual treatment, as shown in [this recording](https://www.youtube.com/watch?v=jlWEic3AhFY&t=1614s). confirmed In another recording, a player with no alternative uses Mindwipe, at a heavy cost. confirmed Forum players recommend carrying sodium nitroprusside to bring blood pressure down, and keeping procoagulant or Braingrow on hand. reported Details are in the [L.R.D., Braingrow and Mindwipe guide](https://casualtieswiki.wiki/items/lrd-braingrow-mindwipe/). Note that since 7.0, items that reduce stroke do not magically fix vision, so blurred sight can linger after treatment. confirmed A stroke also leaves [brain damage](https://casualtieswiki.wiki/health/brain-damage/) behind. ## How do you lower blood pressure? Remove the cause first. If the sense of doom moodle is active, deal with or escape the elder thornback. reported Then treat the pressure itself. Blood pressure moodles do not appear during cardiac arrest, so a missing warning is not good news if your heart has stopped. confirmed Opioids cause vasodilation since 6.1, which lowers pressure, and sepsis affects pressure much less than it did. confirmed ## What is fibrillation? A chaotic heart rhythm. The 6.1 notes say fibrillation **rises quickly only above 280 bpm**, at 4× speed rather than 5×. confirmed Pushing your heart that hard is the danger, and so is epinephrine: the in-game text on the combat pen says that going over 40 mL of epinephrine will cause fibrillation. confirmed Amiodarone reduces fibrillation faster since 6.1. confirmed Oxyline stabilises it too, according to the same in-game text. confirmed ## How do you survive cardiac arrest? The heart has stopped, so you are running out of time. | Tool | Notes | Status | | --- | --- | --- | | Automatic defibrillator | One of two types added in 6.0 | confirmed | | Manual defibrillator | A skill minigame; players also use it as a heart rate monitor | confirmed | | Epinephrine | “A low chance to restart the heart if it stops” | confirmed | | Auto-pump | Keeps blood moving while your heart cannot | reported | | CPR | Available in the [co-op mod](https://casualtieswiki.wiki/mods/multiplayer/) | confirmed | The 6.1 notes spell out one important point: **defibrillators no longer always fix asystole**. confirmed Do not count on a single shock. Even so, players will often try anything: forum users report that a tesla coil can shock the heart in an emergency, and it may take brain damage to do so. unverified ## What is the auto-pump? A device that pumps blood mechanically. It was reworked in 6.0, while the older auto-auto-pump was removed as obsolete. confirmed Recordings show players strapping one on when things are going wrong. confirmed It treats the symptom, not the cause, so keep looking for what stopped the heart. ## How do you avoid heart trouble in Casualties Unknown? - Read drug labels before injecting. The combat pen gives you the mix and doses in its description. - Do not stack stimulants. A popular forum tip of “take all the drugs when dying” is for when a run is already lost, not a treatment plan. - Carry at least one heart-rate monitor if you find one. A manual defibrillator doubles as this. - Keep your [mood](https://casualtieswiki.wiki/survival/mood-and-moodles/) up, since a good mood helps in a [last stand](https://casualtieswiki.wiki/survival/last-stand/) if the worst happens. See the [medicine list](https://casualtieswiki.wiki/items/medicine-and-drugs/) for what each drug does. ## Sources Last checked 9 November 2026. Marks: confirmed = official notes, in-game text or a recording of the game; reported = two or more players; unverified = one source. - [v6.0 Patch Notes, Steam](https://steamstore-a.akamaihd.net/news/externalpost/steam_community_announcements/1830163047266090) · cardiovascular rework - [6.1 Demo Patch Notes, Steam](https://steamstore-a.akamaihd.net/news/externalpost/steam_community_announcements/1830797770233957) · stroke, fibrillation, defibrillators - [7.0 Demo Update notes, Steam](https://steamstore-a.akamaihd.net/news/externalpost/steam_community_announcements/1834602721186794) - [Casualties: Unknown on Steam](https://store.steampowered.com/app/4576490/) · combat pen text - [Recording: stroke and Braingrow](https://www.youtube.com/watch?v=jlWEic3AhFY&t=1614s) · 26:54 - [Steam forum: How do I treat or avoid this?](https://steamcommunity.com/app/4576490/discussions/0/567048683131235272/) · player reports on blood pressure ## More in Health - [Limb damage How to fix shrapnel, dislocations and fractures, when to amputate and how prosthetics work.](https://casualtieswiki.wiki/health/limb-damage/) - [Bleeding and blood How to bandage, which wound comes first, and how to treat internal bleeding and hemothorax.](https://casualtieswiki.wiki/health/bleeding-and-blood/) - [Brain damage What causes brain damage, what the symptoms mean and how to recover from it.](https://casualtieswiki.wiki/health/brain-damage/) - [Infection and radiation How infections start, how to clean and disinfect, how radiation builds up and how to treat it.](https://casualtieswiki.wiki/health/infection-and-radiation/)