[Hemodynamics in acute myocardial infarct].

With the Swan-Ganz catheter it has become possible to measure the hemodynamics repeatedly in patients with acute myocardial infarction. It was shown that the majority of these patients have an elevated filling pressure but cardiac output and stroke volume remain normal. The clinical signs of a third sound, rales and elevated venous pressure are therefore due to the initial backward failure but are not signs of depressed cardiac output. However, in a small group of patients with clinical signs of flow output, treatment with diurectis and vasodilators is necessary. The mean filling pressure of the left ventricle in this subgroup was 26.2 +/- 2 mm Hg at entrance and could be effectively lowered with both treatments. On the other hand, the cardiac index at entrance (2.3 +/- 0.21/min/m2) did not change significantly under vasodilation but in some cases fell dangerously under furosemide. It is therefore considered that in patients with a low output syndrome hemodynamic monitoring is necessary not only when they are treated with vasodilators but also under furosemide.