Cardiogenic shock

Cardiogenic shock (CS) is a medical emergency resulting from inadequate blood flow due to the dysfunction of the ventricles of the heart. Signs of inadequate blood flow include low urine production (<30 mL/hour), cool arms and legs, and altered level of consciousness. People may also have a severely low blood pressure and heart rate.Ultrasound showing cardiogenic shock due to myocarditisUltrasound showing cardiogenic shock due to myocarditisUltrasound showing cardiogenic shock due to myocarditis Cardiogenic shock (CS) is a medical emergency resulting from inadequate blood flow due to the dysfunction of the ventricles of the heart. Signs of inadequate blood flow include low urine production (<30 mL/hour), cool arms and legs, and altered level of consciousness. People may also have a severely low blood pressure and heart rate. Causes of cardiogenic shock include cardiomyopathic, arrhythmic, and mechanical. CS is most commonly precipitated by acute myocardial infarction. Cardiogenic shock is a type of circulatory shock, there is insufficient blood flow and oxygen supply for biological tissues to meet the metabolic demands for oxygen and nutrients. Cardiogenic shock is defined by sustained low blood pressure with tissue hypoperfusion despite adequate left ventricular filling pressure. People can have combined types of shock. Shock by definition is inadequate blood circulation to the rest of the body, which causes organ damage. Organs do not have enough oxygen delivery, and cannot adequately maintain their cellular metabolism. Treatment of cardiogenic shock depends on the cause with the initial goals to improve blood flow to the body. This can done in a number of ways—fluid resuscitation, blood transfusions, vasopressors, and ionotropes. If cardiogenic shock is due to a heart attack, attempts to open the heart's arteries may help. An intra-aortic balloon pump or left ventricular assist device may improve matters until this can be done. Medications that improve the heart's ability to contract (positive inotropes) may help; however, it is unclear which is best. Norepinephrine may be better if the blood pressure is very low whereas dopamine or dobutamine may be more useful if only slightly low. Cardiogenic shock is a condition that is difficult to fully reverse even with an early diagnosis. With that being said, early initiation of mechanical circulatory support, early percutaneous coronary intervention, inotropes, and heart transplantation may improve outcomes. Mortality rates have been decreasing in the United States. This is likely due to the rapid identification and treatment of the CS. Some studies have suggested that this possibly related to the increased use of coronary reperfusion strategies, like heart stents. Nonetheless, the mortality rates remain high. Multi-organ failure is associated with higher rates of mortality. Cardiogenic shock is caused by the failure of the heart to pump effectively. It is due to damage to the heart muscle, most often from a heart attack or myocardial contusion. Other causes include abnormal heart rhythms, cardiomyopathy, heart valve problems, ventricular outflow obstruction (i.e. systolic anterior motion (SAM) in hypertrophic cardiomyopathy), or ventriculoseptal defects.It can also be caused by a sudden decompressurization (e.g. in an aircraft), where air bubbles are released into the bloodstream (Henry's law), causing heart failure. An electrocardiogram helps to establish the exact diagnosis and guides treatment, it may reveal: Echocardiography may show poor ventricular function, signs of PED, rupture of the interventricular septum, an obstructed outflow tract or cardiomyopathy. The Swan-Ganz catheter or pulmonary artery catheter may assist in the diagnosis by providing information on the hemodynamics. When cardiomyopathy is suspected as the cause of cardiogenic shock, a biopsy of heart muscle may be needed to make a definite diagnosis.