| Cardiogenic shock is characterized by a decreased | | | | incidence of cardiogenic shock is higher in men |
| pumping ability of the heart that causes a | | | | compared to women because of the increased |
| shocklike state (ie, global hypoperfusion). | | | | prevalence of coronary artery disease in males. |
| Cardiogenic shock has a death rate of about 60% | | | | Cardiogenic shock can be caused by disorders of |
| and is the major cause of death in patients | | | | the heart muscle, the valves, or the heart's |
| hospitalized for a heart attack. It most commonly | | | | electrical conduction system. Cardiogenic shock is |
| occurs in association with, and as a direct result | | | | life threatening and requires emergency medical |
| of, acute myocardial infarction (AMI). The most | | | | treatment. Dopamine, dobutamine, epinephrine, |
| common cause of cardiogenic shock is extensive | | | | norepinephrine, amrinone, or other medications |
| acute myocardial infarction, although a smaller | | | | may be required to increase blood pressure and |
| infarction in a patient with previously compromised | | | | heart functioning. Echocardiography may show |
| left ventricular function may also precipitate shock. | | | | arrhythmia, signs of PED, ventricular septal |
| Cardiogenic shock is defined by sustained | | | | rupture (VSR), an obstructed outflow tract or |
| hypotension with tissue hypoperfusion despite | | | | cardiomyopathy. Pain medicine may be given if |
| adequate left ventricular filling pressure. Signs of | | | | necessary. Bed rest is recommended to reduce |
| tissue hypoperfusion include oliguria. Cardiogenic | | | | demands on the heart. Coronary artery bypass |
| shock is characterized by both systolic and | | | | grafting. In this surgery, arteries or veins from |
| diastolic dysfunction. Patients who develop | | | | other parts of the body are used to bypass (that |
| cardiogenic shock from acute MI consistently | | | | is, go around) narrowed coronary arteries. The |
| have evidence of progressive myocardial necrosis | | | | use of the IABP reduces systolic left ventricular |
| with infarct extension. Decreased coronary | | | | afterload and augments diastolic coronary |
| perfusion pressure and increased myocardial | | | | perfusion pressure, thereby increasing cardiac |
| oxygen demand play a role in the vicious cycle | | | | output and improving coronary artery blood flow. |
| that leads to cardiogenic shock. | | | | Heart monitoring, including hemodynamic |
| Cardiogenic shock occurs in 8.6% of patients with | | | | monitoring, to guide treatment. |
| ST-segment elevation MI with 29% of those | | | | Treatment for Cardiogenic Shock Tips |
| presenting to the hospital already in shock. It | | | | 1. Inotropic medications should be considered in |
| occurs only in 2% of non–ST-segment | | | | systems with appropriately trained paramedical |
| elevation MI. Outcomes significantly improve only | | | | personnel. |
| when rapid revascularization can be achieved. The | | | | 2. In case of cardiac arrhythmia several |
| recent SHOCK trial demonstrated that overall | | | | anti-arrhythmic agents may be administered, i.e. |
| mortality when revascularization occurs is 38%. | | | | adenosine, verapamil, amiodarone, ß-blocker. |
| When rapid revascularization is not attempted, | | | | 3. Balloon angioplasty (PTCA) may be an |
| mortality rates approach 70%. Cardiogenic shock | | | | alternative to surgery in some cases. |
| can also be caused by mechanical | | | | 4. Oxygen reduces the workload of the heart by |
| complications—such as acute mitral | | | | reducing tissue demands for blood flow. |
| regurgitation, rupture of the interventricular | | | | 5. Heart monitoring, including hemodynamic |
| septum, or rupture of the free wall—or by | | | | monitoring, to guide treatment |
| large right ventricular infarctions. Myocardial | | | | 6. Coronary artery bypass grafting. In this |
| ischemia causes a decrease in contractile function, | | | | surgery, arteries or veins from other parts of the |
| which leads to left ventricular dysfunction and | | | | body are used to bypass (that is, go around) |
| decreased arterial pressure; these, in turn, | | | | narrowed coronary arteries. |
| exacerbate the myocardial ischemia. The overall | | | | |