[Therapy of cardiogenic shock in acute myocardial infarct].

Cardiogenic shock in acute myocardial infarction patients is the most common cause of in-hospital death. Various studies showed, that 60 to 100% of patients in cardiogenic shock will die, if no early reperfusion of their coronary artery could be established. The incidence of cardiogenic shock has decreased during the last years, most likely due to early thrombolytic therapy and administration of nitroglycerin. Reasons for cardiogenic shock are either necrosis of 40% or more of the left ventricular wall, right heart infarction, or complications which can be treated by the surgeon, like papillary muscle rupture, ventricular septal defect or rupture of the free ventricular wall. Diagnosis is based on clinical criteria, echocardiography, and on hemodynamic monitoring. The hemodynamic criteria for cardiogenic shock are a cardiac index of < 2.2/l, and an increased wedge pressure of > 18 mm Hg; additionally, diuresis is usually < 20 ml/h. Therapy can be divided into the following categories: a) pharmaceutical interventions to increase cardiac output like vasodilators or positive inotrope drugs; b) mechanical support systems; c) acute interventions with the aim of reperfusion; d) acute surgical interventions addressing complications like papillary muscle rupture, ventricular septal defect or rupture of the free ventricular wall. While steps a) and b) are able to stabilize the hemodynamical situation in patients with cardiogenic shock, they are rarely the definitive treatment. Point c), reperfusion of the coronary artery, can be divided in thrombolysis or acute PTCA. Thrombolysis failed to show a beneficial effect in most studies, either after intravenous or intracoronary application. On contrast, acute PTCA showed to be of great benefit in various studies with a technical success rate of 54 to 100% and a survival rate of patients from 58 to 100%. Thus, emergency PTCA is the treatment of choice in cardiogenic shock. Point d), surgical interventions can be divided in acute bypass grafting, which should be reserved for patients with severe multivessel disease, left main involvement, or failed PTCA. Furthermore, acute heart transplantation is effective, but will be possible in a minority of patients only. The last part of surgically manageable complications are surgery of papillary muscle rupture and ventricular septal defect. Results of early surgery in papillary muscle rupture or ventricular septal defects are much better than delayed interventions. Rupture of the free wall is usually a fatal event. In summary, the most successful therapy of cardiogenic shock is early emergency PTCA.(ABSTRACT TRUNCATED AT 400 WORDS)