[Reduction of myocardial infarction mortality in Chilean hospitals].
BACKGROUND
The characteristics of patients with acute myocardial infarction (MI) admitted to 37 Chilean hospitals (GEMI Registry Group), have been analyzed in the period 1993-1995 and 1997-1998.


OBJECTIVE
To report the changes in hospital mortality between these 2 periods, with a particular emphasis on the impact of treatment.


METHODS
Between 1993-1995 we collected information from 2,957 patients and between 1997-1998 we registered 1,981 patients with MI. Analysis of the changes in mortality between periods was adjusted by demographic variables, coronary risk factors, MI location, Killip class on admission and the different therapeutic strategies utilized. The effects of different treatments on hospital mortality were adjusted by the previously determined mortality risk variables.


RESULTS
Hospital mortality decreased from 13.3% to 10.8% between both periods (Odds Ratio (OR) 0.78, confidence intervals (95%) (CI) 0.65-0.93). A significant reduction in mortality was observed among patients below 60 years of age, in men, in diabetics and in subjects with an infarction classified as Killip class over II. The use of beta blockers (OR 0.65, CI 0.42-0.99) and intravenous nitrates (OR 0.78, CI 0.61-0.99) and the lower use of calcium channel blockers (OR 0.72, CI 0.60-0.87) were significantly associated with a lower mortality. The administration of angiotensin converting enzyme inhibitors was associated with a 29.3% mortality reduction (OR 0.69, CI 0.47-1.02).


CONCLUSIONS
There has been a significant reduction in the mortality rate for MI in Chilean hospitals during the 2 registry periods analyzed, which was significant among some high risk patients and was related to treatment changes, according to evidence based guidelines.
Corbalán
Ramón
R
Hospital Clínico de la Universidad Católica de Chile, Marcoleta 367, Piso 6, Servicio Unidad Coronaria, Santiago-Chile.
Nazzal
Carolina
C
Prieto
Juan Carlos
JC
Chávez
Eduardo
E
Lanas
Fernando
F
Lamich
Rubén
R
Bartolucci
Jorge
J
Montaño
Rosa
R
Cumsille
Francisco
F
D000368:Aged; D002677:Chile / Q000453:epidemiology; D005260:Female; D006333:Heart Failure / Q000401:mortality; D017052:Hospital Mortality / Q000639:trends*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000188:drug therapy / Q000401:mortality*; D012307:Risk Factors