Early rather than delayed administration of lisinopril protects the heart after myocardial infarction in rats.
BACKGROUND
ACE inhibitors have shown beneficial results in several studies after myocardial infarction (MI). However, these studies have shown conflicting results about the ideal starting time of the ACE inhibitors administration after MI and the importance of infarct size.


OBJECTIVE
This study was designed to assess the long-term effects of lisinopril on mortality, cardiac function, and ventricular fibrosis after MI, in rats.


METHODS
Lisinopril (20 mg/kg/day) was given on day 1 or 21 days after coronary occlusion in small or large infarctions.


RESULTS
The mortality rate was reduced by 39 % in early treatment and 30 % in delayed treatment in comparison to the untreated rats. Early treatment reduced cardiac dysfunction in small MIs; however, delayed treatment did not. No statistical difference was observed among the groups for large MIs. No statistical difference was observed among the groups with large or small MIs on myocardial hydroxyproline concentration.


CONCLUSIONS
Both early and delayed treatments with lisinopril increased survival. Treatment exerts no marked effects on fibrosis; early treatment has exerted beneficial influences on cardiac function whereas delayed treatment had no consistent effects. The protective effect of lisinopril is detectable only in small (< 40 % of LV) MIs.
Zornoff
L A
LA
Departamento de Clínica Médica, Faculdade de Medicina de Botucatu, UNESP, Brazil.
Matsubara
B B
BB
Matsubara
L S
LS
Paiva
S A
SA
Spadaro
J
J
D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage* / Q000627:therapeutic use; D000818:Animals; D003971:Diastole; D005355:Fibrosis; D006321:Heart / Q000187:drug effects*; D017706:Lisinopril / Q000008:administration & dosage* / Q000627:therapeutic use; D008297:Male; D009203:Myocardial Infarction / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology / Q000503:physiopathology; D009206:Myocardium / Q000473:pathology; D011312:Pressure; D051381:Rats; D017208:Rats, Wistar; D016019:Survival Analysis; D013599:Systole; D013997:Time Factors; D016277:Ventricular Function, Left / Q000187:drug effects
D000806:Angiotensin-Converting Enzyme Inhibitors; D017706:Lisinopril