Cardiogenic shock
Definition
Cardiogenic shock is a state in which the heart has been damaged so much that it is unable to supply enough blood to the organs of the body.
Alternative Names
Shock - cardiogenicCauses
Shock occurs whenever the heart is unable to pump enough blood for the needs of the body. Cardiogenic shock can be caused by disorders of the:
- Heart muscle
- Heart's electrical conduction system
- Valves
The most common cause is a heart attack (myocardial infarction), resulting in heart failure.
Some related disorders include:
- Abnormal heart rhythms
- Cardiomyopathy
- Heart valve disorders (especially leaky valves)
- Rupture of the heart
Symptoms
- Anxiety, nervousness
- Coma
- Decreased mental status
- Loss of ability to concentrate
- Loss of alertness
- Decreased urine output (or none)
- Pale skin color or blotchy (mottled) skin
- Profuse sweating, moist skin
- Rapid breathing
- Rapid pulse
- Restlessness, agitation, confusion
- Skin that feels cool to the touch
- Weak (thready) pulse
- Weakness, lethargy, fatigue
Exams and Tests
An examination will reveal low blood pressure (less than 90 systolic). The blood pressure may drop more than 10 points when you stand up after lying down (orthostatic hypotension). The pulse may be weak (thready).
To diagnose cardiogenic shock, a catheter (tube) may be placed in the pulmonary artery (right heart catheterization). Measurements often indicate that blood is backing up into the lungs and the heart is not pumping properly.
Tests include:
- Coronary angiography
- Echocardiogram
- Electrocardiogram
- Nuclear scans
Other tests may be recommended to determine why the heart is not functioning properly.
Laboratory tests include:
- Arterial blood gas
- Blood chemistry (chem-7, chem-20, electrolytes, cardiac enzymes)
- CBC
Treatment
Cardiogenic shock is a medical emergency. Treatment requires hospitalization. The goal of treatment is to save your life and treat the cause of shock.
Medications may be needed to increase blood pressure and heart function, including:
- Dopamine
- Dobutamine
- Epinephrine
- Norepinephrine
You may receive pain medicine if necessary. Bed rest is recommended to reduce demands on the heart.
Getting oxygen lowers the workload of the heart by reducing tissue demands for blood flow.
You may receive intravenous fluids, including blood and blood products, if needed.
Other treatments for shock may include:
- Cardiac catheterization with coronary angioplasty and stenting
- Heart monitoring, including hemodynamic monitoring, to guide treatment
- Heart surgery (coronary artery bypass surgery, heart valve replacement, left ventricular assist device)
- Intra-aortic balloon counterpulsation (IABP) to improve heart and blood vessel function
- Pacemaker
Outlook (Prognosis)
In the past, the death rate from cardiogenic shock ranged from 80% - 90%. In more recent studies, this rate has improved to between 50% - 75%.
When cardiogenic shock is not treated, the outlook is not good.
Possible Complications
- Brain damage
- Kidney damage
- Liver damage
When to Contact a Medical Professional
Go to the emergency room or call the local emergency number (such as 911) if you have symptoms. Cardiogenic shock is a medical emergency.
Prevention
You may reduce the risk by quickly and aggressively treating any related disorders.
References
Anderson JL, Adams CD, Antman EM, Bridges CR, Califf RM, Casey DE, et al. ACC/AHA 2007 guidelines for the management of patients with unstable angina/non-ST-Eevation myocardial infarction: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 2002 Guidelines for the Management of Patients With Unstable Angina/Non-ST-Elevation Myocardial Infarction) developed in collaboration with the American College of Emergency Physicians, the Society for Cardiovascular Angiography and Interventions, and the Society of Thoracic Surgeons endorsed by the American Association of Cardiovascular and Pulmonary Rehabilitation and the Society for Academic Emergency Medicine. J Am Coll Cardiol. 2007;50:e1-e57.
Antman EM. ST-Elevation Myocardial Infarction: management. In: Libby P, Bonow RO, Mann DL, Zipes DP. Libby: Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 8th ed. Philadelphia, Pa:Saunders; 2007:chap 51.
Reviewed By: Alan Berger, MD, Assistant Professor, Divisions of Cardiology and Epidemiology, University of Minnesota, Minneapolis, MN. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
