🕷️ Crawler Inspector

URL Lookup

Direct Parameter Lookup

Raw Queries and Responses

1. Shard Calculation

Query:

Response:

Calculated Shard: 129 (from laksa114)

2. Crawled Status Check

Query:

curl -X POST \
  'http://laksa129.int.ahrefs:8124/' \
  -H 'Content-Type: text/plain' \
  -H 'X-ClickHouse-Database: crawler3' \
  -H 'Authorization: Basic YXBpOg==' \
  -d 'SELECT getAhrefsURLFromUnparsed(src_unparsed) AS found_url, ifNull(toUnixTimestamp(download_stamp), 0) AS crawl_time, ifNull(toUnixTimestamp(props_url_first_seen), 0) AS first_indexed_time, download_http_code AS http_code, src_unparsed AS src_unparsed, src_root_hash AS src_root_hash, history_drop_reason AS history_drop_reason, meta_title AS meta_title, meta_descriptions AS meta_descriptions, attrs_boilerpipe_text AS attrs_boilerpipe_text, attrs_markdown AS attrs_markdown, attrs_readable_markdown AS attrs_readable_markdown, meta_canonical AS meta_canonical, ml_categories_json AS ml_categories_json, ml_types_json AS ml_types_json, ml_intent_types_json AS ml_intent_types_json, meta_language AS meta_language, attrs_author AS attrs_author, ifNull(toUnixTimestamp(attrs_publish_time), 0) AS attrs_publish_time, ifNull(toUnixTimestamp(attrs_original_publish_time), 0) AS attrs_original_publish_time, ifNull(attrs_is_republished, 0) AS attrs_is_republished, ifNull(attrs_nr_words, 0) AS attrs_nr_words, ifNull(attrs_boilerpipe_nr_words, 0) AS attrs_boilerpipe_nr_words, ifNull(body_ext_links_number, 0) AS body_ext_links_number, ifNull(body_int_links_number, 0) AS body_int_links_number, ifNull(meta_nofollow, 0) AS meta_nofollow, ifNull(meta_noarchive, 0) AS meta_noarchive, ifNull(props_was_rendered, 0) AS props_was_rendered, ifNull(src_redirect, \'\') AS src_redirect, ifNull(download_time_msec, 0) AS download_time_msec, ifNull(download_ttfb_msec, 0) AS download_ttfb_msec, ifNull(download_size, 0) AS download_size FROM crawler3.page_info_local FINAL PREWHERE (src_root_hash, src_unparsed) IN ((getAhrefsRootHashFromUnparsed(getAhrefsUnparsedNoserviceFromURL(\'https://www.nhlbi.nih.gov/health/cardiac-arrest/symptoms\')), getAhrefsUnparsedNoserviceFromURL(\'https://www.nhlbi.nih.gov/health/cardiac-arrest/symptoms\'))) FORMAT JSONEachRow'

Response:

{"found_url":"https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/symptoms","crawl_time":1767383342,"first_indexed_time":0,"http_code":200,"src_unparsed":"gov,nih!nhlbi,www,\/health\/cardiac-arrest\/symptoms s443","src_root_hash":"7295144728021232729","history_drop_reason":null,"meta_title":"Cardiac Arrest - Symptoms | NHLBI, NIH","meta_descriptions":["Learn the symptoms and early warning signs of cardiac arrest, such as chest pain and shortness of breath, and how to tell the difference between cardiac arrest and a heart attack."],"attrs_boilerpipe_text":"It is likely that a person is having a cardiac arrest if they:\nCollapse suddenly and lose consciousness (pass out)\nAre not breathing or their breathing is ineffective or they are gasping for air\nDo not respond to shouting or shaking\nDo not have a pulse\nIf you think someone is having a cardiac arrest,\ncall 9-1-1\nand then start CPR right away. You do not need to try to find a pulse.\nCardiac arrest or heart attack? Know the difference.\nMany people confuse cardiac arrests and\nheart attacks\n. A cardiac arrest is caused by an electrical problem in the heart that stops the heartbeat. It is often fatal unless someone takes immediate action. A heart attack is caused by a blocked\narteries\n in the heart. The loss of blood flow damages the heart muscle, but the heart usually keeps beating.\nFACT SHEET\nOur fact sheet describes heart attack warning signs and explains how to take action if you have symptoms.\nView the fact sheet\nWhat are the warning signs?\nMost people who had a cardiac arrest had one or more symptoms in the hour before the event. Some symptoms may even appear a few weeks before a cardiac arrest. But many people who have a cardiac arrest had no prior symptoms.\nPossible warning signs of a heart attack, a key cause of cardiac arrest, include those listed below.\nShortness of breath\n(more common in women than men) \nExtreme tiredness\n(unusual fatigue)\nBack pain\nFlu-like symptoms\nBelly pain, nausea, and vomiting\nChest pain, mainly\nangina\n \n(more common in men than women) \nRepeated dizziness or fainting,\nespecially while exercising hard, sitting, or lying on your back\nHeart palpitations\n, or feeling as if your heart is racing, fluttering, or skipping a beat\nWhen to call your healthcare provider\nCall your healthcare provider if you have warning signs, such as fainting or chest pain, that might signal a higher\nrisk of cardiac arrest\n. Your provider will do an exam, check your health history, and do tests to help assess your heart health. If you have\ncoronary heart disease\nor other conditions that may increase your risk of a future cardiac arrest, work with your healthcare team to set up a\ntreatment plan\nthat works for you.\nDo not ignore symptoms\nPeople who get medical care for warning signs are 5 times more likely to survive cardiac arrest. If you have a warning sign, see your healthcare provider.","attrs_markdown":"[Skip to main content](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/symptoms#main-content)\n\n![U.S. flag](https:\/\/www.nhlbi.nih.gov\/themes\/custom\/nhlbi\/assets\/uswds\/dist\/img\/us_flag_small.png)\n\nAn official website of the United States government\n\nHere’s how you know\n\nHere’s how you know\n\n![](https:\/\/www.nhlbi.nih.gov\/themes\/custom\/nhlbi\/assets\/uswds\/dist\/img\/icon-dot-gov.svg)\n\n**Official websites use .gov**  \n A **.gov** website belongs to an official government organization in the United States.\n\n![](https:\/\/www.nhlbi.nih.gov\/themes\/custom\/nhlbi\/assets\/uswds\/dist\/img\/icon-https.svg)\n\n**Secure .gov websites use HTTPS**  \n A **lock** ( A locked padlock) or **https:\/\/** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.\n\n[![National Heart, Lung, and Blood Home](https:\/\/www.nhlbi.nih.gov\/themes\/custom\/nhlbi\/images\/NHLBI-logo.svg)](https:\/\/www.nhlbi.nih.gov\/)\n\n- Health Topics\n  - [All Health Topics A-Z](https:\/\/www.nhlbi.nih.gov\/health)\n    - [Asthma](https:\/\/www.nhlbi.nih.gov\/health\/asthma)\n    - [Heart-Healthy Living](https:\/\/www.nhlbi.nih.gov\/health\/heart-healthy-living)\n    - [High Blood Pressure](https:\/\/www.nhlbi.nih.gov\/health\/high-blood-pressure)\n    - [Sickle Cell Disease](https:\/\/www.nhlbi.nih.gov\/health\/sickle-cell-disease)\n    - [Sleep Apnea](https:\/\/www.nhlbi.nih.gov\/health\/sleep-apnea)\n  - [Calculate Your BMI](https:\/\/www.nhlbi.nih.gov\/calculate-your-bmi)\n- Health Education\n  - [Education Programs and Initiatives](https:\/\/www.nhlbi.nih.gov\/education)\n    - [The Heart Truth®](https:\/\/www.nhlbi.nih.gov\/health-topics\/education-and-awareness\/heart-truth)\n    - [Learn More Breathe Better®](https:\/\/www.nhlbi.nih.gov\/BreatheBetter)\n    - [Blood Diseases & Disorders Education Program](https:\/\/www.nhlbi.nih.gov\/education\/blood)\n  - [Publications and Resources](https:\/\/www.nhlbi.nih.gov\/resources?f%5B0%5D=language%3AEnglish)\n- Research\n  - [Clinical Trials and Studies](https:\/\/www.nhlbi.nih.gov\/research\/clinical-trials)\n  - [Research Focus Areas](https:\/\/www.nhlbi.nih.gov\/science)\n    - [Blood Disorders and Blood Safety](https:\/\/www.nhlbi.nih.gov\/science\/blood-disorders-and-blood-safety)\n    - [Sleep Science and Sleep Disorders](https:\/\/www.nhlbi.nih.gov\/science\/sleep-science-and-sleep-disorders)\n    - [Lung Diseases](https:\/\/www.nhlbi.nih.gov\/science\/lung-diseases)\n    - [Health Disparities](https:\/\/www.nhlbi.nih.gov\/science\/health-disparities)\n    - [Heart and Vascular Diseases](https:\/\/www.nhlbi.nih.gov\/science\/heart-and-vascular-diseases)\n    - [Precision Medicine Activities](https:\/\/www.nhlbi.nih.gov\/science\/precision-medicine-activities)\n    - [Obesity, Nutrition, and Physical Activity](https:\/\/www.nhlbi.nih.gov\/science\/obesity-nutrition-and-physical-activity)\n    - [Population and Epidemiology Studies](https:\/\/www.nhlbi.nih.gov\/science\/population-and-epidemiology-studies)\n    - [Women’s Health](https:\/\/www.nhlbi.nih.gov\/science\/womens-health)\n  - [Research Topics](https:\/\/www.nhlbi.nih.gov\/research\/research-topics)\n  - [All Science A-Z](https:\/\/www.nhlbi.nih.gov\/science\/all-science)\n- Grants and Training\n  - [Grants and Training Home](https:\/\/www.nhlbi.nih.gov\/grants-and-training)\n  - [Policies and Guidelines](https:\/\/www.nhlbi.nih.gov\/grants-and-training\/policies-procedures-and-guidelines)\n  - [Funding Opportunities and Contacts](https:\/\/www.nhlbi.nih.gov\/grants-and-training\/funding-opportunities-and-contacts)\n  - [Training and Career Development](https:\/\/www.nhlbi.nih.gov\/grants-and-training\/training-and-career-development)\n- News and Events\n  - [News and Events Home](https:\/\/www.nhlbi.nih.gov\/news-and-events)\n    - [Email Alerts](https:\/\/www.nhlbi.nih.gov\/news-and-events\/email-alerts)\n  - [All News](https:\/\/www.nhlbi.nih.gov\/news)\n    - [NHLBI News](https:\/\/www.nhlbi.nih.gov\/news?f%5B0%5D=type%3Anews_mention)\n    - [NHLBI in the Press](https:\/\/www.nhlbi.nih.gov\/news?f%5B0%5D=type%3Apress_release)\n    - [Featured Article](https:\/\/www.nhlbi.nih.gov\/news?f%5B0%5D=type%3Afeature_article)\n    - [Ask a Scientist](https:\/\/www.nhlbi.nih.gov\/ask-a-scientist)\n  - [All Events](https:\/\/www.nhlbi.nih.gov\/events)\n    - [Past Events](https:\/\/www.nhlbi.nih.gov\/events?f%5B0%5D=event_status%3Aclosed)\n    - [Upcoming Events](https:\/\/www.nhlbi.nih.gov\/events?f%5B0%5D=event_status%3Aupcoming)\n- About NHLBI\n  - [About NHLBI Home](https:\/\/www.nhlbi.nih.gov\/about)\n    - [Mission and Strategic Vision](https:\/\/www.nhlbi.nih.gov\/about\/strategic-vision)\n    - [Leadership](https:\/\/www.nhlbi.nih.gov\/about\/leadership)\n    - [Divisions, Offices and Centers](https:\/\/www.nhlbi.nih.gov\/about\/divisions)\n    - [Advisory Committees](https:\/\/www.nhlbi.nih.gov\/about\/advisory-and-peer-review-committees)\n    - [Budget and Legislative Information](https:\/\/www.nhlbi.nih.gov\/about\/budget-and-legislative-information)\n    - [Jobs and Working at the NHLBI](https:\/\/www.nhlbi.nih.gov\/about\/working-at-nhlbi)\n    - [Contact and FAQs](https:\/\/www.nhlbi.nih.gov\/contact)\n    - [NIH Sleep Research Plan](https:\/\/www.nhlbi.nih.gov\/sleep-research-plan)\n- [HOME](https:\/\/www.nhlbi.nih.gov\/)\n\nCardiac Arrest\n\n- [Home](https:\/\/www.nhlbi.nih.gov\/)\n- [\\< Back To Cardiac Arrest](https:\/\/www.nhlbi.nih.gov\/node\/93126)\n- Symptoms\n\n0\n\n[Cardiac Arrest](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/symptoms)\n\n[MENU]()\n\n- [Home](https:\/\/www.nhlbi.nih.gov\/)\n- [\\< Back To Cardiac Arrest](https:\/\/www.nhlbi.nih.gov\/node\/93126)\n- Symptoms\n\n- [What Is Cardiac Arrest?](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest)\n- [Symptoms](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/symptoms)\n- [Diagnosis](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/diagnosis)\n- [Causes and Risk Factors](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/causes)\n- [Treatment](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/treatment)\n- [Life After](https:\/\/www.nhlbi.nih.gov\/node\/93988)\n- [Living With](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/living-with)\n\nMORE INFORMATION\n\n[Participate in a Study](https:\/\/www.nhlbi.nih.gov\/research\/clinical-trials?f%5B0%5D=disease_or_condition_name%3ACardiac%20Arrest)\n\nCardiac Arrest\n\n# Cardiac Arrest Symptoms\n[![Share](https:\/\/www.nhlbi.nih.gov\/themes\/custom\/nhlbi\/images\/share-alt-icon.svg)](https:\/\/www.addtoany.com\/share#url=https%3A%2F%2Fwww.nhlbi.nih.gov%2Fhealth%2Fcardiac-arrest%2Fsymptoms&title=Symptoms \"Share\")\n\n[Email](https:\/\/www.nhlbi.nih.gov\/#email \"Email\")\n\n[Print](https:\/\/www.nhlbi.nih.gov\/#print \"Print\")\n\n## Language switcher\n- [English](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/symptoms)\n- [Español](https:\/\/www.nhlbi.nih.gov\/es\/salud\/paro-cardiaco\/sintomas)\n\nIt is likely that a person is having a cardiac arrest if they:\n\n- Collapse suddenly and lose consciousness (pass out)\n- Are not breathing or their breathing is ineffective or they are gasping for air\n- Do not respond to shouting or shaking\n- Do not have a pulse\n\nIf you think someone is having a cardiac arrest, **call 9-1-1** and then start CPR right away. You do not need to try to find a pulse.\n\n### Cardiac arrest or heart attack? Know the difference.\nMany people confuse cardiac arrests and [heart attacks](https:\/\/www.nhlbi.nih.gov\/health\/heart-attack). A cardiac arrest is caused by an electrical problem in the heart that stops the heartbeat. It is often fatal unless someone takes immediate action. A heart attack is caused by a blocked  [arteries](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/symptoms \"Definition of artery \")  in the heart. The loss of blood flow damages the heart muscle, but the heart usually keeps beating.\n\n![Learn what a heart attack feels like flyer](https:\/\/www.nhlbi.nih.gov\/sites\/default\/files\/styles\/crop_callout\/public\/2022-05\/Heart%20attack.png?itok=XSHFiKPP)\n\nFACT SHEET\n\nOur fact sheet describes heart attack warning signs and explains how to take action if you have symptoms.\n\n[View the fact sheet](https:\/\/www.nhlbi.nih.gov\/resources\/learn-what-heart-attack-feels-fact-sheet)\n\n## What are the warning signs?\nMost people who had a cardiac arrest had one or more symptoms in the hour before the event. Some symptoms may even appear a few weeks before a cardiac arrest. But many people who have a cardiac arrest had no prior symptoms.\n\nPossible warning signs of a heart attack, a key cause of cardiac arrest, include those listed below.\n\n- **Shortness of breath** (more common in women than men)\n- **Extreme tiredness** (unusual fatigue)\n- **Back pain**\n- **Flu-like symptoms**\n- **Belly pain, nausea, and vomiting**\n- **Chest pain, mainly** [**angina**](https:\/\/www.nhlbi.nih.gov\/health\/angina)(more common in men than women)\n- **Repeated dizziness or fainting,** especially while exercising hard, sitting, or lying on your back\n- **Heart palpitations**, or feeling as if your heart is racing, fluttering, or skipping a beat\n\n## When to call your healthcare provider\nCall your healthcare provider if you have warning signs, such as fainting or chest pain, that might signal a higher [risk of cardiac arrest](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/causes). Your provider will do an exam, check your health history, and do tests to help assess your heart health. If you have [coronary heart disease](https:\/\/www.nhlbi.nih.gov\/health\/coronary-heart-disease) or other conditions that may increase your risk of a future cardiac arrest, work with your healthcare team to set up a [treatment plan](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/treatment) that works for you.\n\n### Do not ignore symptoms\nPeople who get medical care for warning signs are 5 times more likely to survive cardiac arrest. If you have a warning sign, see your healthcare provider.\n\n### Book traversal links for 93125\n- #### Previous\n  [What Is Cardiac Arrest?](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest \"Go to previous page\")\n- #### Next\n  [Diagnosis](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/diagnosis \"Go to next page\")\n\nLast updated on\n\nMay 27, 2022\n\nBack To Top Link\n\n[Back to top](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/symptoms#main-content)\n\nWeb Policies & Notices\n\n- [Accessibility](https:\/\/www.nhlbi.nih.gov\/about\/contact\/website-privacy-and-accessibility)\n- [No FEAR Act Data](https:\/\/eeo.nih.gov\/no-fear-act)\n- [Privacy Policy](https:\/\/www.nhlbi.nih.gov\/about\/contact\/website-privacy-and-accessibility\/privacy-statement)\n- [Freedom of Information Act (FOIA)](https:\/\/www.nhlbi.nih.gov\/about\/contact\/website-privacy-and-accessibility)\n- [HHS Vulnerability Disclosure](https:\/\/www.hhs.gov\/vulnerability-disclosure-policy\/index.html) [(link is external)](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/symptoms)\n\nRelated Government Websites\n\n- [Health and Human Services](https:\/\/www.hhs.gov\/) [(link is external)](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/symptoms)\n- [National Institutes of Health](https:\/\/www.nih.gov\/)\n- [Office of the Inspector General](https:\/\/oig.hhs.gov\/) [(link is external)](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/symptoms)\n- [USA.gov](https:\/\/www.usa.gov\/) [(link is external)](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/symptoms)\n\nStay Connected\n\n- ![chat bubbles](https:\/\/www.nhlbi.nih.gov\/themes\/custom\/nhlbi\/images\/messages-question-regular.svg) [Live Chat](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/symptoms)\n  Live Chat with us, Monday through Friday, 8:30 a.m. to 5:00 p.m. EST.\n- ![envelope](https:\/\/www.nhlbi.nih.gov\/themes\/custom\/nhlbi\/images\/envelope-open-text-solid.svg)[Get Email Alerts](https:\/\/www.nhlbi.nih.gov\/news-and-events\/email-alerts)\n  Receive automatic alerts about NHLBI related news and highlights from across the Institute.\n\nFooter Bottom\n\n[![National Heart, Lung, and Blood Home](https:\/\/www.nhlbi.nih.gov\/themes\/custom\/nhlbi\/images\/NHLBI_HHS_Lockup_white.svg)](https:\/\/www.nhlbi.nih.gov\/)\n\n- [Contact Us](https:\/\/www.nhlbi.nih.gov\/contact)\n- [Site Index](https:\/\/www.nhlbi.nih.gov\/siteindex)\n- [Jobs](https:\/\/www.nhlbi.nih.gov\/about\/working-at-nhlbi)\n\n- [![Facebook social media](https:\/\/www.nhlbi.nih.gov\/themes\/custom\/nhlbi\/images\/ico-facebook-white.svg)](https:\/\/www.facebook.com\/NIH.NHLBI)\n- [![Youtube social media](https:\/\/www.nhlbi.nih.gov\/themes\/custom\/nhlbi\/images\/ico-youtube-white.svg)](https:\/\/www.youtube.com\/user\/NHLBI)\n- [![LinkedIn social media](https:\/\/www.nhlbi.nih.gov\/themes\/custom\/nhlbi\/images\/linkedin-brands.svg)](https:\/\/www.linkedin.com\/company\/national-heart-lung-and-blood-institute)\n\n✓\n\nThanks for sharing\\!\n\n[AddToAny](https:\/\/www.addtoany.com\/ \"Share Buttons\")\n\n[More…](https:\/\/www.nhlbi.nih.gov\/health\/cardiac-arrest\/symptoms#addtoany \"Show all\")\n\nExternal Web Site Policy\n\nClose\n\nOK","attrs_readable_markdown":null,"meta_canonical":null,"ml_categories_json":"{\"\/Health\":997,\"\/Health\/Health_Conditions\":984,\"\/Health\/Health_Conditions\/Heart_and_Hypertension\":983}","ml_types_json":"{\"\/Article\":990,\"\/Article\/Definitions\":471}","ml_intent_types_json":"{\"Informational\":999}","meta_language":"en","attrs_author":null,"attrs_publish_time":1653652800,"attrs_original_publish_time":1648314909,"attrs_is_republished":1,"attrs_nr_words":"839","attrs_boilerpipe_nr_words":"407","body_ext_links_number":12,"body_int_links_number":71,"meta_nofollow":0,"meta_noarchive":0,"props_was_rendered":1,"src_redirect":"","download_time_msec":85,"download_ttfb_msec":82,"download_size":18921}

3. Robots.txt Check

Query:

Response:

4. Spam/Ban Check

Query:

Response:

5. Seen Status Check

ℹ️ Skipped - page is already crawled

📄

INDEXABLE

✅

CRAWLED

3 months ago

🤖

ROBOTS ALLOWED

Page Info Filters

Filter	Status	Condition	Details
HTTP status	PASS	`download_http_code = 200`	HTTP 200
Age cutoff	PASS	`download_stamp > now() - 6 MONTH`	3.7 months ago
History drop	PASS	`isNull(history_drop_reason)`	No drop reason
Spam/ban	PASS	`fh_dont_index != 1 AND ml_spam_score = 0`	ml_spam_score=0
Canonical	PASS	`meta_canonical IS NULL OR = '' OR = src_unparsed`	Not set

Page Details

Property

Value

URL

https://www.nhlbi.nih.gov/health/cardiac-arrest/symptoms

Last Crawled

2026-01-02 19:49:02 (3 months ago)

First Indexed

not set

HTTP Status Code

200

Content

Meta Title

Cardiac Arrest - Symptoms | NHLBI, NIH

Meta Description

Learn the symptoms and early warning signs of cardiac arrest, such as chest pain and shortness of breath, and how to tell the difference between cardiac arrest and a heart attack.

Meta Canonical

null

Boilerpipe Text

It is likely that a person is having a cardiac arrest if they: Collapse suddenly and lose consciousness (pass out) Are not breathing or their breathing is ineffective or they are gasping for air Do not respond to shouting or shaking Do not have a pulse If you think someone is having a cardiac arrest, call 9-1-1 and then start CPR right away. You do not need to try to find a pulse. Cardiac arrest or heart attack? Know the difference. Many people confuse cardiac arrests and heart attacks . A cardiac arrest is caused by an electrical problem in the heart that stops the heartbeat. It is often fatal unless someone takes immediate action. A heart attack is caused by a blocked arteries in the heart. The loss of blood flow damages the heart muscle, but the heart usually keeps beating. FACT SHEET Our fact sheet describes heart attack warning signs and explains how to take action if you have symptoms. View the fact sheet What are the warning signs? Most people who had a cardiac arrest had one or more symptoms in the hour before the event. Some symptoms may even appear a few weeks before a cardiac arrest. But many people who have a cardiac arrest had no prior symptoms. Possible warning signs of a heart attack, a key cause of cardiac arrest, include those listed below. Shortness of breath (more common in women than men) Extreme tiredness (unusual fatigue) Back pain Flu-like symptoms Belly pain, nausea, and vomiting Chest pain, mainly angina (more common in men than women) Repeated dizziness or fainting, especially while exercising hard, sitting, or lying on your back Heart palpitations , or feeling as if your heart is racing, fluttering, or skipping a beat When to call your healthcare provider Call your healthcare provider if you have warning signs, such as fainting or chest pain, that might signal a higher risk of cardiac arrest . Your provider will do an exam, check your health history, and do tests to help assess your heart health. If you have coronary heart disease or other conditions that may increase your risk of a future cardiac arrest, work with your healthcare team to set up a treatment plan that works for you. Do not ignore symptoms People who get medical care for warning signs are 5 times more likely to survive cardiac arrest. If you have a warning sign, see your healthcare provider.

Markdown

[Skip to main content](https://www.nhlbi.nih.gov/health/cardiac-arrest/symptoms#main-content) ![U.S. flag](https://www.nhlbi.nih.gov/themes/custom/nhlbi/assets/uswds/dist/img/us_flag_small.png) An official website of the United States government Here’s how you know Here’s how you know ![](https://www.nhlbi.nih.gov/themes/custom/nhlbi/assets/uswds/dist/img/icon-dot-gov.svg) **Official websites use .gov** A **.gov** website belongs to an official government organization in the United States. ![](https://www.nhlbi.nih.gov/themes/custom/nhlbi/assets/uswds/dist/img/icon-https.svg) **Secure .gov websites use HTTPS** A **lock** ( A locked padlock) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites. [![National Heart, Lung, and Blood Home](https://www.nhlbi.nih.gov/themes/custom/nhlbi/images/NHLBI-logo.svg)](https://www.nhlbi.nih.gov/) - Health Topics - [All Health Topics A-Z](https://www.nhlbi.nih.gov/health) - [Asthma](https://www.nhlbi.nih.gov/health/asthma) - [Heart-Healthy Living](https://www.nhlbi.nih.gov/health/heart-healthy-living) - [High Blood Pressure](https://www.nhlbi.nih.gov/health/high-blood-pressure) - [Sickle Cell Disease](https://www.nhlbi.nih.gov/health/sickle-cell-disease) - [Sleep Apnea](https://www.nhlbi.nih.gov/health/sleep-apnea) - [Calculate Your BMI](https://www.nhlbi.nih.gov/calculate-your-bmi) - Health Education - [Education Programs and Initiatives](https://www.nhlbi.nih.gov/education) - [The Heart Truth®](https://www.nhlbi.nih.gov/health-topics/education-and-awareness/heart-truth) - [Learn More Breathe Better®](https://www.nhlbi.nih.gov/BreatheBetter) - [Blood Diseases & Disorders Education Program](https://www.nhlbi.nih.gov/education/blood) - [Publications and Resources](https://www.nhlbi.nih.gov/resources?f%5B0%5D=language%3AEnglish) - 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[Home](https://www.nhlbi.nih.gov/) - [\< Back To Cardiac Arrest](https://www.nhlbi.nih.gov/node/93126) - Symptoms 0 [Cardiac Arrest](https://www.nhlbi.nih.gov/health/cardiac-arrest/symptoms) [MENU]() - [Home](https://www.nhlbi.nih.gov/) - [\< Back To Cardiac Arrest](https://www.nhlbi.nih.gov/node/93126) - Symptoms - [What Is Cardiac Arrest?](https://www.nhlbi.nih.gov/health/cardiac-arrest) - [Symptoms](https://www.nhlbi.nih.gov/health/cardiac-arrest/symptoms) - [Diagnosis](https://www.nhlbi.nih.gov/health/cardiac-arrest/diagnosis) - [Causes and Risk Factors](https://www.nhlbi.nih.gov/health/cardiac-arrest/causes) - [Treatment](https://www.nhlbi.nih.gov/health/cardiac-arrest/treatment) - [Life After](https://www.nhlbi.nih.gov/node/93988) - [Living With](https://www.nhlbi.nih.gov/health/cardiac-arrest/living-with) MORE INFORMATION [Participate in a Study](https://www.nhlbi.nih.gov/research/clinical-trials?f%5B0%5D=disease_or_condition_name%3ACardiac%20Arrest) Cardiac Arrest # Cardiac Arrest Symptoms [![Share](https://www.nhlbi.nih.gov/themes/custom/nhlbi/images/share-alt-icon.svg)](https://www.addtoany.com/share#url=https%3A%2F%2Fwww.nhlbi.nih.gov%2Fhealth%2Fcardiac-arrest%2Fsymptoms&title=Symptoms "Share") [Email](https://www.nhlbi.nih.gov/#email "Email") [Print](https://www.nhlbi.nih.gov/#print "Print") ## Language switcher - [English](https://www.nhlbi.nih.gov/health/cardiac-arrest/symptoms) - [Español](https://www.nhlbi.nih.gov/es/salud/paro-cardiaco/sintomas) It is likely that a person is having a cardiac arrest if they: - Collapse suddenly and lose consciousness (pass out) - Are not breathing or their breathing is ineffective or they are gasping for air - Do not respond to shouting or shaking - Do not have a pulse If you think someone is having a cardiac arrest, **call 9-1-1** and then start CPR right away. You do not need to try to find a pulse. ### Cardiac arrest or heart attack? Know the difference. Many people confuse cardiac arrests and [heart attacks](https://www.nhlbi.nih.gov/health/heart-attack). A cardiac arrest is caused by an electrical problem in the heart that stops the heartbeat. It is often fatal unless someone takes immediate action. A heart attack is caused by a blocked [arteries](https://www.nhlbi.nih.gov/health/cardiac-arrest/symptoms "Definition of artery ") in the heart. The loss of blood flow damages the heart muscle, but the heart usually keeps beating. ![Learn what a heart attack feels like flyer](https://www.nhlbi.nih.gov/sites/default/files/styles/crop_callout/public/2022-05/Heart%20attack.png?itok=XSHFiKPP) FACT SHEET Our fact sheet describes heart attack warning signs and explains how to take action if you have symptoms. [View the fact sheet](https://www.nhlbi.nih.gov/resources/learn-what-heart-attack-feels-fact-sheet) ## What are the warning signs? Most people who had a cardiac arrest had one or more symptoms in the hour before the event. Some symptoms may even appear a few weeks before a cardiac arrest. But many people who have a cardiac arrest had no prior symptoms. Possible warning signs of a heart attack, a key cause of cardiac arrest, include those listed below. - **Shortness of breath** (more common in women than men) - **Extreme tiredness** (unusual fatigue) - **Back pain** - **Flu-like symptoms** - **Belly pain, nausea, and vomiting** - **Chest pain, mainly** [**angina**](https://www.nhlbi.nih.gov/health/angina)(more common in men than women) - **Repeated dizziness or fainting,** especially while exercising hard, sitting, or lying on your back - **Heart palpitations**, or feeling as if your heart is racing, fluttering, or skipping a beat ## When to call your healthcare provider Call your healthcare provider if you have warning signs, such as fainting or chest pain, that might signal a higher [risk of cardiac arrest](https://www.nhlbi.nih.gov/health/cardiac-arrest/causes). Your provider will do an exam, check your health history, and do tests to help assess your heart health. If you have [coronary heart disease](https://www.nhlbi.nih.gov/health/coronary-heart-disease) or other conditions that may increase your risk of a future cardiac arrest, work with your healthcare team to set up a [treatment plan](https://www.nhlbi.nih.gov/health/cardiac-arrest/treatment) that works for you. ### Do not ignore symptoms People who get medical care for warning signs are 5 times more likely to survive cardiac arrest. 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