What is Cardiogenic Shock | Causes | Diagnose | Symptoms | Treatment

What is Cardiogenic shock?

Cardiogenic shock (CS) is characterized by systemic hypoperfusion due to severe depression of the cardiac index (<2.2 [L/min]/m2) and sustained systolic arterial hypotension despite an elevated filling pressure (pulmonary capillary wedge pressure. It is associated with in-hospital mortality rates >50%. Circulatory failure based on cardiac dysfunction may be caused by primary myocardial failure, most commonly secondary to acute myocardial infarction (MI), and less frequently by cardiomyopathy or myocarditis, cardiac tamponade, or critical valvular heart disease.

It is also define as cardiogenic shock occurs when the heart has been damaged so much that it is unable to supply enough blood to the vital organs of the body. As a result of the failure of the heart to pump enough nutrients to the body, blood pressure falls and organs may begin to fail.

What are the Causes of Cardiogenic Shock?

In most scenario, a lack of oxygen to your heart, usually from a heart attack, damages its main pumping chamber (left ventricle). Without oxygen-rich blood circulating to that area of your heart, the heart muscle can weaken and go into cardiogenic shock.

Rarely, damage to your heart's right ventricle, which sends blood to your lungs to receive oxygen, leads to cardiogenic shock.

Other possible causes of cardiogenic shock include:

Inflammation of the heart muscle (myocarditis)

Infection of the heart valves (endocarditis)

Weakened heart from any cause

Drug overdoses or poisoning with substances that can affect your heart's pumping ability

pulmonary embolism (sudden blockage of an artery in the lung)

pericardial tamponade (fluid buildup around the heart reducing its filling capacity)

sudden valvular regurgitation (damage to the valves allowing the backflow of blood)

rupture of the wall of the heart (due to increased pressure)

inability of heart muscle to work properly (or at all in some cases)

ventricular fibrillation (an arrhythmia in which the lower chambers fibrillate or quiver)

ventricular tachycardia (an arrhythmia where the ventricles beat too fast)

How to Diagnose Cardiogenic Shock?

Following method doctor can use diagnosis cardiogenic shock:

Chest X-ray is a non-invasive test that takes pictures of the heart and lungs; these can help the doctor determine if there’s a problem that is causing chest pain.

Electrocardiogram (ECG) is a simple non-invasive test that can be done in the doctor’s office using small adhesive pads called electrodes that are placed on the arms, legs, and chest. These electrodes are connected to a machine that detects and prints out the heart's electrical impulses, giving a 10-second snapshot of what the heart is doing right at that moment.

Blood tests are used to determine if there is too much carbon dioxide or not enough oxygen in the blood – indicators of shock. Blood tests also used to measure for certain enzymes that indicate kidney or liver damage, while high levels of certain heart muscle biochemicals (eg, CK, CK-MB, troponin, serum myoglobin) suggest a heart attack.

Echocardiogram is a non-invasive test using ultrasound (sound waves) and a device called a transducer — which is placed on the surface of the chest — (ultrasound) to create a moving picture of the heart. It shows the size and shape of the heart chambers, and reveals problems with pumping function perhaps due to a heart attack.

Left heart catheterization uses a catheter (long thin flexible tube) that is inserted through an artery in the leg, arm, or neck and guided to either the coronary artery to check for blockages, or to the inside of the heart to measure volume or pressure, or to take pictures of heart walls or valves.

Right heart catheterization uses a catheter (long thin flexible tube) that is inserted through a vein in the leg, arm or neck and guided to the right side of the heart to provide a closer look at the pulmonary artery, which delivers blood from the heart to the lungs. Using this approach your doctor can check blood pressure to see if blood is "backing up" and damaging the heart, and evaluate volume status, heart function and the artery’s ability to deliver enough oxygen to the body.  

What are The Symptoms of Cardiogenic Shock

Following are the symptoms of cardiogenic shock:

Severe shortness of breath and rapid breathing.

Tachycardia (rapid heartbeat).

Mental alteration or confusion.

Loss of consciousness.

Weak/faint pulse.

Pale, clammy skin and sweating.

The hands or feet feel cold.

Decreased urine output or no urine output.

What are the treatment of cardiogenic shock

Depending on the type of cardiogenic shock, treatment involves infusion of fluids, or in shock refractory to fluids, inotropic medications. In case of an abnormal heart rhythm several anti-arrhythmic agents may be administered, e.g. adenosine.

Positive inotropic agents (such as dobutamine or milrinone), which enhance the heart's pumping capabilities, are used to improve the contractility and correct the low blood pressure. Should that not suffice an intra-aortic balloon pump (which reduces workload for the heart, and improves perfusion of the coronary arteries) or a left ventricular assist device (which augments the pump-function of the heart) can be considered.[1][2][3] Finally, as a last resort, if the person is stable enough and otherwise qualifies, heart transplantation, or if not eligible an artificial heart, can be placed. These invasive measures are important tools—more than 50% of patients who do not die immediately due to cardiac arrest from a lethal abnormal heart rhythm and live to reach the hospital (who have usually suffered a severe acute myocardial infarction, which in itself still has a relatively high mortality rate), die within the first 24 hours. The mortality rate for those still living at time of admission who suffer complications (among others, cardiac arrest or further abnormal heart rhythms, heart failure, cardiac tamponade, a ruptured or dissecting aneurysm, or another heart attack) from cardiogenic shock is even worse around 85%, especially without drastic measures such as ventricular assist devices or transplantation.

Cardiogenic shock may be treated with intravenous dobutamine, which acts on β1 receptors of the heart leading to increased contractility and heart rate.

For Cardigenic shock treatment you can also consult with Dr Boon Lim - Best Cardiologist in London Cardiovascular Clinic, 66 Harley Street, London, W1G 7HD, UK.