SymptomHeart & circulation
Signs of Cardiogenic Shock: How to Recognize It
Cardiogenic shock happens when the heart suddenly pumps so weakly that the organs are starved of blood. Its signs are cold, clammy, pale or mottled skin, a fast and weak pulse, confusion or drowsiness, severe breathlessness, low blood pressure and passing little urine. It most often follows a large heart attack. It is a life-threatening emergency: call 911 or your local emergency number at once, because survival depends on rapid hospital treatment.
Also called: Cardiac shock, pump failure, heart pump failure shock
At a glance
- What it is
- Sudden failure of the heart's pumping, so organs do not get enough blood and oxygen.
- Key signs
- Cold, clammy, mottled skin; fast weak pulse; confusion; severe breathlessness; low urine output.
- Most common cause
- A large heart attack, usually affecting the left ventricle.
- Urgency
- A medical emergency with high mortality; every minute counts.
- What to do
- Call 911, keep the person lying down (or sitting up if breathless), and start CPR if they stop breathing normally.
When to get help
Call 911 or go to the ER
- Chest pain or pressure with cold, clammy skin, confusion, fainting or extreme weakness
- Severe shortness of breath, frothy or pink sputum, or being unable to lie flat, with a fast weak pulse
- Blood pressure below 90 systolic with lightheadedness, mottled skin or little or no urine, in someone with heart disease
- Collapse, unresponsiveness or not breathing normally: call 911 and start CPR
See a doctor within a day or two
- Worsening breathlessness, leg swelling and tiredness over days in someone with known heart failure
- A recent heart attack followed by new dizziness, very low blood pressure readings at home, or reduced urine
Book a routine appointment
- Regular review if you have heart failure or have had a heart attack, including medicines and a written action plan
What cardiogenic shock looks like
Shock is not just feeling shaken. In medicine it means the circulation is failing to deliver enough oxygen to the body's tissues. In cardiogenic shock, the cause is the heart itself. The body tries to protect the brain and heart by squeezing blood vessels in the skin, gut and kidneys, which produces the classic picture:
- Skin: cold, pale, gray or bluish, clammy and sweaty. A blotchy, lace-like pattern on the knees or legs (mottling) is a sign of severe shock.
- Pulse: fast (often over 100 beats per minute) and weak or thready, sometimes irregular.
- Blood pressure: usually low, below 90 systolic, though it can be near normal early on.
- Breathing: fast and labored. Fluid backing up into the lungs causes crackling breathing, coughing, frothy pink sputum and being unable to lie flat.
- Brain: restlessness, anxiety, confusion, drowsiness or fainting.
- Kidneys: little or no urine.
- Neck veins: may look swollen.
Most people also have signs of the cause, especially the chest pain, pressure, sweating and nausea of a heart attack.
Who is at risk
- people having a heart attack, especially a large one, an older adult, or someone with diabetes or previous heart attacks
- people with advanced heart failure whose condition suddenly worsens
- anyone with acute inflammation of the heart muscle, such as myocarditis
- people with a very fast or very slow abnormal heart rhythm
- people with sudden valve failure, such as a torn mitral valve after a heart attack
- people with a large blood clot in the lungs or fluid compressing the heart (tamponade), which cause a similar "obstructive" shock
Cardiogenic shock vs other causes of shock
| Type of shock | Cause | Skin | Clues |
|---|---|---|---|
| Cardiogenic | Heart pump failure | Cold, clammy | Chest pain, breathlessness, lung crackles |
| Hypovolemic | Blood or fluid loss | Cold, clammy | Bleeding, vomiting, diarrhea, burns |
| Septic | Severe infection | Often warm early, later cold | Fever, infection source |
| Anaphylactic | Severe allergy | Flushed, hives | Swelling, wheeze after a trigger |
Only hospital assessment can tell these apart reliably, and they can overlap. All are emergencies.
What to do while waiting for help
- Call 911 or your local emergency number and describe the symptoms, including chest pain.
- Position: if the person is breathless, help them sit upright, which eases fluid in the lungs. If they are faint and not breathless, lay them flat.
- Aspirin: if a heart attack is suspected and the person is awake, not allergic and not told to avoid it, they can chew one regular 325 mg aspirin, as the dispatcher advises.
- Do not give food or drink, and do not let them walk around.
- Loosen tight clothing and keep them warm.
- If they become unresponsive and are not breathing normally, start CPR with hard, fast chest compressions and use an AED if one is available.
What happens in hospital
Emergency teams confirm the diagnosis with an ECG, blood pressure monitoring, an echocardiogram (heart ultrasound) and blood tests including lactate, which rises when tissues are short of oxygen. The usual cause, a blocked coronary artery, is treated by opening it urgently with a stent. Medicines support blood pressure and heart contraction, and mechanical pumps may take over some of the heart's work. See cardiogenic shock for treatment, causes and outlook in detail.
Frequently asked questions
What are the first signs of cardiogenic shock?
Early signs are a fast pulse, cold and sweaty skin, anxiety or restlessness, shortness of breath, and lightheadedness, usually alongside chest pain from a heart attack. Blood pressure may still be normal at first. Confusion, mottled skin and little urine signal worsening shock.
How is cardiogenic shock different from a heart attack?
A heart attack is damage to heart muscle from a blocked artery. Cardiogenic shock is a complication in which the damaged heart can no longer pump enough blood for the body. It occurs in a small minority of heart attacks but carries a much higher risk of death.
Can you survive cardiogenic shock?
Yes. With rapid treatment that reopens blocked arteries and supports the circulation, about half or more of patients survive to leave hospital. Survival is better the earlier treatment starts, which is why calling 911 immediately for heart attack symptoms matters.
Does cardiogenic shock happen suddenly?
It usually develops over minutes to hours during or after a large heart attack, but it can build over days in people with worsening heart failure or myocarditis. Any rapid decline with cold skin, confusion and breathlessness needs emergency care.
Sources
This guide was written from current patient and clinical guidance, including:
- American Heart Association: Cardiogenic Shock
- National Heart, Lung, and Blood Institute: Cardiogenic Shock
- MedlinePlus: Cardiogenic shock
- American Heart Association: Warning Signs of a Heart Attack
- Society for Cardiovascular Angiography and Interventions (SCAI): Clinical Expert Consensus Statement on the Classification of Cardiogenic Shock