How Is Cardiogenic Shock Diagnosed?

The first step in diagnosing cardiogenic shock is to identify that a person is in shock. At that point, emergency treatment should be started.

Once emergency treatment is started, doctors can look for the specific cause of the shock. If the reason for the shock is that the heart isn't pumping strongly enough, then the diagnosis is cardiogenic shock.

Tests that are useful in diagnosing cardiogenic shock include:

• Blood pressure. Using a simple blood pressure sleeve and stethoscope, doctors can check to see if a person has very low blood pressure, the most common sign of shock. This can easily be done before the patient goes to the hospital. Very low blood pressure also can have less serious causes, including simple fainting and side effects of medicines, such as medicines that treat high blood pressure.
• EKG (electrocardiogram). This test detects and records the electrical activity of the heart, measuring the rate and regularity of the heartbeat. Doctors use EKG to diagnose severe heart attack and monitor your heart's condition.
• Chest x ray. This test takes pictures of organs and structures inside your chest, including the heart, lungs, and blood vessels. A chest x ray shows whether the heart is enlarged or whether there is fluid in the lungs, which can be signs of cardiogenic shock.
• Echocardiography. This test uses sound waves to create a moving picture of your heart. Echocardiography provides information about the size and shape of your heart and how well your heart chambers and valves are working. The test also can identify areas of heart muscle that aren't contracting normally. Not enough blood is flowing to these areas.
• Coronary angiography. This test is an x-ray exam of the heart and blood vessels. The doctor passes a catheter (a thin, flexible tube) through an artery in your leg or arm to your heart. The catheter can measure the pressure inside the various chambers of your heart. A dye that can be seen on x ray is injected into the blood through the tip of the catheter. The dye lets the doctor study the flow of blood through the heart and blood vessels and see any blockages that exist.

Certain blood tests also are used to diagnose cardiogenic shock, including:

• Arterial blood gas measurement. In this test, a blood sample is taken from an artery to measure oxygen, carbon dioxide, and pH (acidity) in the blood. Doctors look for abnormalities in these levels that are associated with shock.
• Cardiac enzymes. When cells in the heart die, they release enzymes into the blood called markers or biomarkers. Measuring these markers can show whether the heart is damaged and the extent of the damage.
• Tests that measure the function of various organs, such as the kidneys and liver. If these organs aren't working right, it could be a sign that they aren't getting enough blood and oxygen, which could be a sign of cardiogenic shock.