Drugs

Question 1

When does concentration of cTnI change with Doxorubicin chemotherapy?

Answer 1

1 month after treatment completion (5x). And cc. correlated with left ventricular ejection fraction and left ventricular dimension in diastole. (Beaumier, JVIM, 2020)
+ the downregulation of miRNA-502 occured before change in cTni (before the 3rd chemo dose)

Question 2

Does the duration of intravenous Doxorubicin (1 hour vs. 15min) has an effect on the occurance of cardiotoxicity?
(Hallmann, JVIM 2018)

Answer 2

No, there was no differnce.
Higher cumulative dose (150m2), higher body weight (large breeds!), decrease of fractional shortening after 5 doses, development of premature contractions had an inffulunece.

Question 3

What is the overall incidence of Doxo induced cardiotoxicity?
And in high vs. low-risk breeds?
(Hallmann, JVIM 2018)

Answer 3

4%
high-risk: 15.4%
Low-risk: 3%

Question 4

Was there a relevant relationship between DOX AUC and neutropenia?
(Wittenburg, VCO 2019)

Answer 4

Yes.
No sig, change was seen in lymphos, PLT, RBC, Hb).
The absolute dose and dose per unit body weight (mg/kg) were not sig. correlated with neutrophil nadir.
No relationship was found between max serum doxol ( metabolite of DOX) and myelosuppression.