Digitoxin prolongs survival of female rats with heart failure due to large myocardial infarction.
BACKGROUND
We analyzed whether digitoxin affects the survival of rats with congestive heart failure.


RESULTS
The influence of digitoxin (0.1 mg.100 g.day, orally) on the survival of infarcted female rats (n=170) randomized as Control Infarcted (CI, n=85) or Digitoxin (D, n=85) was evaluated for 280 days. Mean survival was 235+/-7 days for CI and 255+/-5 days for D (log-rank test: P=.0602). Digitoxin did not affect survival in rats with congestive heart failure from myocardial infarction <40% of the left ventricle, but did prolong survival in rats with infarction >or=40%. The log-rank test defined higher mortality (P=.0161) in CI >40% (56%) than in D >40% (34%), with a hazard ratio of 2.03. Pulmonary water content and papillary muscle mechanics were analyzed in CI (n=7) and D (n=14) survivors. Significant differences were observed regarding pulmonary water content (CI: 82+/-0.3; D: 80+/-0.3%; P=.0014), developed tension (CI: 2.7+/-0.3; D: 3.8+/-0.3g/mm(2); P=.0286) and +dT/dt (CI: 24+/-3; D: 39+/-4 mg mm(2).s; P=.0109).


CONCLUSIONS
In conclusion, long-term digitoxin administration reduced cardiac impairment after myocardium infarction, attenuated myocardial dysfunction, reduced pulmonary congestion, and provided the first evidence regarding the efficiency of digitoxin in prolonging survival in experimental cardiac failure.
Helber
Izo
I
Cardiac Physiology and Physiopathology Laboratory, Federal University of São Paulo, São Paulo, Brazil.
Dos Santos
Alexandra A
AA
Antonio
Ednei L
EL
Flumignan
Ronald L G
RL
Bocalini
Danilo S
DS
Piccolo
Camila
C
Gheorghiade
Mihai
M
Tucci
Paulo J F
PJ
D000818:Animals; D004074:Digitoxin / Q000627:therapeutic use*; D004195:Disease Models, Animal; D005260:Female; D006333:Heart Failure / Q000188:drug therapy* / Q000209:etiology / Q000401:mortality*; D009203:Myocardial Infarction / Q000150:complications / Q000188:drug therapy* / Q000401:mortality*; D051381:Rats; D017208:Rats, Wistar; D015996:Survival Rate / Q000639:trends; D016896:Treatment Outcome
D004074:Digitoxin