Heart Failure vs Heart Attack vs Cardiac Arrest: Which One?
At a Glance
Heart failure is a pumping problem, a heart attack blocks blood flow to heart muscle, and cardiac arrest is a sudden electrical problem that stops effective circulation. A heart attack or severe heart failure can trigger cardiac arrest, so call emergency services for sudden severe symptoms.
In this answer
5 sections
Emergency Warning: If you or someone else is experiencing severe or sudden shortness of breath, new chest pressure, extreme weakness, or fainting, call your local emergency number (like 911 in the US) immediately. Do not drive yourself.
Congestive heart failure, a heart attack, and cardiac arrest are three distinct cardiovascular conditions, though they are deeply connected. To put it simply:
- Heart failure is a pumping or filling problem where the heart cannot circulate blood efficiently over time [1].
- A heart attack is a plumbing problem where blood flow to the heart muscle is abruptly blocked [2].
- Cardiac arrest is an electrical emergency where the heart suddenly stops pumping blood to the body, usually due to a dangerous heart rhythm [3].
Quick Comparison
| Condition | Underlying Problem | What it Looks Like | Action to Take |
|---|---|---|---|
| Heart Failure | The heart cannot pump or fill effectively. | Gradual or sudden shortness of breath, leg swelling, and severe fatigue. The person is awake. | Call your doctor for ongoing symptoms. Call 911 for severe or sudden breathlessness. |
| Heart Attack | Blood flow to the heart muscle is blocked. | Chest pressure, arm/jaw pain, or severe fatigue. The person is usually conscious and breathing. | Call 911 immediately. |
| Cardiac Arrest | The heart’s electrical system malfunctions, stopping blood circulation. | Sudden collapse, unresponsiveness, and absent or abnormal breathing (gasping). | Call 911, start CPR, and use an AED immediately. |
What is Congestive Heart Failure?
Heart failure means your heart is not pumping blood or filling with blood as well as it should to meet your body’s needs [1]. It can be a chronic (long-term) condition that develops gradually, or it can happen acutely (suddenly). Because the heart is too weak or stiff to act as an effective pump, blood can back up into the lungs and other parts of the body [1] [4].
Heart failure does not mean your heart has stopped working. Instead, it causes symptoms like shortness of breath, swelling in the legs or abdomen, and feeling constantly tired [1]. While these symptoms share similarities with a heart attack, they do not prove you are having one [4]. However, sudden worsening of heart failure can still be a medical emergency. Ongoing medical management helps relieve symptoms, reduce hospitalizations, and can sometimes improve the heart’s overall function.
What is a Heart Attack?
A heart attack (myocardial infarction) happens when a blockage suddenly stops blood flow to a part of the heart muscle [2]. Most heart attacks are caused by a ruptured plaque (a buildup of fat and cholesterol inside the artery) and a blood clot, though they can also happen from an artery spasm or tear [2] [5]. Starved of oxygen, that section of heart muscle begins to die [2]. A heart attack can permanently damage the heart muscle, and this loss of strength can lead to heart failure later on [6].
- Classic Warning Signs: Symptoms often include a feeling of pressure, tightness, or squeezing in the center of the chest [7]. Other common signs include pain radiating to the arms, neck, jaw, or back, as well as shortness of breath, heavy sweating, and nausea [7] [8].
- Other Possible Symptoms: Anyone can have atypical symptoms, but women, older adults, and individuals with diabetes may be more likely to experience a heart attack differently [9] [10]. They might feel severe fatigue, dizziness, or stomach discomfort without classic chest pain [9]. Do not wait for “classic” chest pain to seek emergency help.
What is Cardiac Arrest?
Cardiac arrest is an immediate, life-threatening emergency where the heart’s electrical system severely malfunctions [3] [11]. The heart may not be literally motionless—it might be quivering chaotically—but it stops pumping enough blood to the brain and body [3] [11].
When someone experiences cardiac arrest, they will suddenly collapse, lose consciousness, and stop breathing normally (they may just gasp or appear to be having a seizure) [3] [11]. A severe heart attack or advanced heart failure can sometimes trigger the dangerous electrical rhythms that cause cardiac arrest, but it can happen for other reasons too [12] [13].
Emergency Protocols: Why You Must Call 911
If you suspect someone is having a heart attack or cardiac arrest, immediately call emergency medical services (like 911 in the US) instead of attempting to drive them to the hospital [14].
- Immediate Treatment: Emergency responders can run an ECG (an electrical tracing of the heart) and provide treatments like oxygen (only if blood oxygen levels are actually low) as soon as they arrive [14] [15] [16].
- Handling Sudden Complications: A heart attack can quickly turn into cardiac arrest [12]. Paramedics are equipped to handle this worst-case scenario on the way to the hospital [14].
- Bystander Action for Cardiac Arrest: If an adult is unresponsive and not breathing normally (or only gasping):
- Call 911 (or your local emergency number) and put the phone on speaker [11].
- Begin chest compressions immediately. The dispatcher will guide you on how to do hands-only CPR [11] [17].
- Apply an AED (Automated External Defibrillator—a device that checks the rhythm and can send a shock) as soon as one is available [11] [18]. Doing CPR and using an AED before paramedics arrive drastically improves a person’s chances of survival [19] [20].
Common questions in this guide
How can I tell a heart attack from heart failure?
Does heart failure mean the heart has stopped?
What should I do if someone may be having a cardiac arrest?
Can a heart attack cause heart failure or cardiac arrest?
Should I drive someone to the hospital for a suspected heart attack?
When should I call emergency services for these heart symptoms?
Related questions
Show more
Get notified when new evidence is published on congestive heart failure.
We monitor PubMed for new peer-reviewed studies on this topic and email a short summary when something meaningful changes.
References
References (20)
- 1
Computer-aided diagnosis of congestive heart failure using ECG signals - A review.
Jahmunah V, Oh SL, Wei JKE, et al.
Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB) 2019; (62()):95-104 doi:10.1016/j.ejmp.2019.05.004.
PMID: 31153403 - 2
Left Ventricular Remodeling after Myocardial Infarction: From Physiopathology to Treatment.
Leancă SA, Crișu D, Petriș AO, et al.
Life (Basel, Switzerland) 2022; (12(8)) doi:10.3390/life12081111.
PMID: 35892913 - 3
Defibrillation for Ventricular Fibrillation: A Shocking Update.
Nichol G, Sayre MR, Guerra F, Poole J
Journal of the American College of Cardiology 2017; (70(12)):1496-1509 doi:10.1016/j.jacc.2017.07.778.
PMID: 28911514 - 4
Urgent Balloon Aortic Valvuloplasty for Worsening Heart Failure in a Patient with Acute Myocardial Infarction and Critical Aortic Stenosis.
Yamada T, Takahashi A
Acta Cardiologica Sinica 2015; (31(1)):75-7 doi:10.6515/acs20131220a.
PMID: 27122850 - 5
Impact of ventricular arrhythmias on patients with spontaneous coronary artery dissection: a systematic review and meta-analysis.
Kaddoura R, Ahmed A, Al-Asnag M, et al.
Panminerva medica 2025; (67(3)):155-163 doi:10.23736/S0031-0808.25.05340-6.
PMID: 40600668 - 6
Heart Failure Complicating Acute Myocardial Infarction; Burden and Timing of Occurrence: A Nation-wide Analysis Including 86 771 Patients From the Cardiovascular Disease in Norway (CVDNOR) Project.
Sulo G, Igland J, Vollset SE, et al.
Journal of the American Heart Association 2016; (5(1)).
PMID: 26744379 - 7
Chest pain characteristics and gender in the early diagnosis of acute myocardial infarction.
Arora G, Bittner V
Current cardiology reports 2015; (17(2)):5 doi:10.1007/s11886-014-0557-5.
PMID: 25618302 - 8
Differences in symptoms and pre-hospital delay among acute myocardial infarction patients according to ST-segment elevation on electrocardiogram: an analysis of China Acute Myocardial Infarction (CAMI) registry.
Fu R, Song CX, Dou KF, et al.
Chinese medical journal 2019; (132(5)):519-524 doi:10.1097/CM9.0000000000000122.
PMID: 30807351 - 9
Gender difference of symptoms of acute coronary syndrome among Chinese patients: a cross-sectional study.
An L, Li W, Shi H, et al.
European journal of cardiovascular nursing 2019; (18(3)):179-184 doi:10.1177/1474515118820485.
PMID: 30556427 - 10
Impact of symptom presentation on in-hospital outcomes in patients with acute myocardial infarction.
Fujino M, Ishihara M, Ogawa H, et al.
Journal of cardiology 2017; (70(1)):29-34 doi:10.1016/j.jjcc.2016.10.002.
PMID: 27856131 - 11
2025 Korean Guidelines for Cardiopulmonary Resuscitation: Part 3. Adult basic life support.
Jang YS, Cho GC, Cho Y, et al.
Clinical and experimental emergency medicine 2026; (13(Suppl 1)):S18-S31 doi:10.15441/ceem.26.095.
PMID: 42297406 - 12
A case of pregnancy-associated acute myocardial infarction with refractory ventricular fibrillation and heart failure.
Hasegawa T, Tabata H, Kagoshima M, et al.
Journal of cardiology cases 2016; (14(1)):13-16 doi:10.1016/j.jccase.2016.03.001.
PMID: 30546650 - 13
Ischemic Cardiomyopathy and Heart Failure After Acute Myocardial Infarction.
Del Buono MG, Moroni F, Montone RA, et al.
Current cardiology reports 2022; (24(10)):1505-1515 doi:10.1007/s11886-022-01766-6.
PMID: 35972638 - 14
Unexpected high level of severe events even in low-risk profile chest pain unit patients.
Breuckmann F, Settelmeier S, Rassaf T, et al.
Herz 2022; (47(4)):374-379 doi:10.1007/s00059-021-05064-9.
PMID: 34463785 - 15
Using High Sensitivity Troponins to Rule Out Acute Coronary Syndrome and Lower Admission Rates.
Potomac W, Diercks DB
Cardiology in review 2019; (27(6)):314-321 doi:10.1097/CRD.0000000000000275.
PMID: 31584473 - 16
2025 Korean Guidelines for Cardiopulmonary Resuscitation: Part 11. First aid.
Woo SH, Lee CH, Kim MY, et al.
Clinical and experimental emergency medicine 2026; (13(Suppl 1)):S185-S194 doi:10.15441/ceem.26.076.
PMID: 42297414 - 17
2025 Korean Guidelines for Cardiopulmonary Resuscitation: Part 2. Current status of cardiac arrest and the chain of survival.
Hwang SO, Cha KC, Jung WJ, et al.
Clinical and experimental emergency medicine 2026; (13(Suppl 1)):S10-S17 doi:10.15441/ceem.26.072.
PMID: 42297405 - 18
Lay Bystanders' Perspectives on What Facilitates Cardiopulmonary Resuscitation and Use of Automated External Defibrillators in Real Cardiac Arrests.
Malta Hansen C, Rosenkranz SM, Folke F, et al.
Journal of the American Heart Association 2017; (6(3)) doi:10.1161/JAHA.116.004572.
PMID: 28288975 - 19
Early cardiopulmonary resuscitation in out-of-hospital cardiac arrest.
Hasselqvist-Ax I, Riva G, Herlitz J, et al.
The New England journal of medicine 2015; (372(24)):2307-15 doi:10.1056/NEJMoa1405796.
PMID: 26061835 - 20
Impact of Bystander Automated External Defibrillator Use on Survival and Functional Outcomes in Shockable Observed Public Cardiac Arrests.
Pollack RA, Brown SP, Rea T, et al.
Circulation 2018; (137(20)):2104-2113 doi:10.1161/CIRCULATIONAHA.117.030700.
PMID: 29483086
This comparison of heart failure, heart attack, and cardiac arrest is for informational purposes only and does not constitute medical advice. Call your local emergency number for sudden or severe symptoms, and ask your clinician for a personalized plan.