What is cardiogenic shock?
Cardiogenic shock occurs when a weakened heart is suddenly unable to pump enough blood. ("Shock" means that not enough blood and oxygen are reaching the brain and other organs; shock may also have non-heart causes, including sudden blood pressure drop due to blood loss, called hypovolemic shock, and sudden relaxation of blood vessels, called vasodilatory shock.) The most common cause of heart-related, or cardiogenic, shock is a severe heart attack (myocardial infarction). This sudden blockage of coronary vessels can damage heart muscle, rupture the wall (septum) between heart chambers, tear tendons that anchor heart valves, or disrupt or block heart rhythms. These serious complications of heart attack can suddenly impair the heart's pumping ability and be fatal if not treated immediately. Other causes of heart damage leading to cardiogenic shock include: heart inflammation (myocarditis) or infection (endocarditis), severe arrhythmias, pericardial tamponade (swelling of fluid in pericardial sac around the heart), and drug overdose.
What are the symptoms?
Typical symptoms of cardiogenic shock may include: rapid breathing and suddenly fast pulse; confusion or lack of alertness; loss of consciousness (coma); sweating, pale skin, and cold hands/feet; decreased urine output. In addition, because heart attack often immediately precedes cardiogenic shock, symptoms may also include angina-type chest pain (heavy uncomfortable pressure, fullness, or squeezing pain); mild or severe pain in the arms, shoulders, back, neck, or jaw; vague discomfort or indigestion; difficulty breathing; anxiety; cold sweat; nausea; vomiting; weakness or fatigue; and anxiety.
IMPORTANT: Call 911 for help right away if you or someone else is having these symptoms of a heart attack or shock.
How is it diagnosed?
Cardiogenic shock should be diagnosed and treated quickly. Initial diagnosis is usually based on:
- Signs and symptoms: as described above, often gathered by emergency medical team
- Blood pressure: Low blood pressure can often be measured in the ambulance
Other tests to make a diagnosis and find the underlying cause may include:
- Chest X-ray
- Electrocardiogram (ECG or EKG): a simple noninvasive test that charts the heart's electrical impulses and reveals signs of a recent heart attack; measured with small electrodes stuck to the chest, legs, and arms
- Blood tests: too much carbon dioxide or not enough oxygen indicate shock; certain enzymes indicate kidney or liver damage; high levels of certain heart muscle biochemicals (eg, CK, CK-MB, troponin, serum myoglobin) suggest a heart attack
- Echocardiogram: a noninvasive test using sound waves (ultrasound) shows the heart chambers and reveals problems with pumping function perhaps due to a heart attack
- Heart catheterization: a catheter (long thin flexible tube) is inserted through a leg, arm, or neck artery and guided to a coronary artery (to check for blockages), inside a heart chamber (to measure volume or pressure, or to take pictures of heart walls or valves)
- Pulmonary artery catheterization: a catheter guided into the pulmonary artery (delivering blood from the heart to the lungs) can check blood pressure here to see if blood is "backing up" and damaging the heart
How is cardiogenic shock treated?
Emergency Medical Treatment: Enriched oxygen in a tube or mask; breathing assistance (ventilator); intravenous (IV) fluids; medications to boost blood pressure or heart function.
Medications: At the hospital, depending on the underlying cause, treatment may include:
- Thrombolytic drugs to dissolve coronary artery clots ("clot-busting" drugs such as tPA)
- Anticlotting agents to prevent new clots (eg, aspirin, clopidogrel, heparin)
- Drugs to increase the heart's pumping ability (eg, dobutamine, dopamine, epinephrine)
- Other possible therapy: oxygen to protect heart tissue; nitroglycerin to widen coronary vessels; drugs to decrease the heart's workload and pain, relieve anxiety, or regulate heart rhythm
Procedures/Devices/Surgery: At Temple, our cardiothoracic surgeons are experienced in advanced medical and surgical techniques to improve heart pumping (temporarily or permanently), open up blocked coronary vessels, repair damage to heart muscle or valves, or restore regular heartbeats. In many cases, a minimally invasive or robotically assisted procedure can be used. Examples:
- To treat a heart attack, a surgeon can perform balloon angioplasty or bypass surgery
- To help the heart pump, an intra-aortic balloon pump can be inserted (this device sits in the main artery of your heart (aorta) and provides an extra push to blood coming out of your heart
- To control heart rhythms, a specialist can perform cardioversion (electrical shock therapy), insert a pacemaker, or perform an ablation procedure
- As needed to treat underlying problems, you may also need valve surgery, heart failure surgery, mechanical circulatory support, or heart transplantation
To schedule an appointment at the Temple Heart and Vascular Center, click here or call 1-800-TEMPLE MED (1-800-836-7536).