[Influence of the use of Swan-Ganz catheter on the mortality from acute myocardial infarction].

OBJECTIVE: to evaluate the statistical significance of the haemodynamic examination making use of the Swan-Ganz catheter (S-G) on the hospitalary mortality of patients (pts) with acute myocardial infarction (AMI). CONCEPTION: Not randomized, not controlled and retrospective study. SETTING: Intensive coronary care unit (CCU). PATIENTS: 2562 pts with AMI sequentially admitted to a CCU were studied. METHODS: The 2562 pts were divided in two groups: Group A--involving 2117 pts not submitted to haemodynamic examination; Group B-constituted by 445 pts (17% of all pts) submitted to haemodynamic examination. All pts admitted to the study were distributed according to the four classes of Killip. The pts included in each Killip class were distributed by the groups A (not catheterized) and B (catheterized). Hospitalary mortalities of the pts included in the global A and B groups, and the mortalities of the patients included in the particular A and B groups in each Killip class were determined. To evaluate the statistical significance of the differences in distributions of the number of pts who survived and who died in each set of A and B groups square chi test was used. Values of p less than 0.05 were considered as statistical significant. RESULTS: The distributions of the pts who died and who survived during the stay in the hospital by the A and B groups, be it in the total group of patients be it in each Killip class, were not significant different (p greater than 0.05). CONCLUSIONS: The mortalities of pts with AMI submitted or not to haemodynamic examination with S-G catheter did not significantly differ even in each Killip class, which means that it was not demonstrated a benefit with the S-G catheter use in the pts with AMI. In the presence of this conclusion and considering that retrospective studies must be interpreted with circumspection, it seems necessary to accomplish a prospective randomized and controlled study for evaluation the risk/benefit relation of the haemodynamic examination with the S-G catheter in pts with AMI.