A comparison of the myocardial depressant effects of several aminoglycoside antibiotics.

The myocardial depressant action of aminoglycosides has been known for a number of years but there was no available data on newer derivatives. We have thus studied the contractile responses of isolated guinea pig left atria to increasing concentrations of gentamicin, tobramycin, lividomycin and amikacin (0.02, 0.04, 0.08, 0.13, 0.17 and 0.22 mM). Our results are consistent with those of previous workers and show that newer aminoglycosides do exert a similar depressant action. As gentamicin and tobramycin are more depressant than lividomycin, then amikacin at similar concentrations, no clear-cut difference was obtained when respecting a relative range of concentrations mimicking that of clinical situations. However, these depressant effects were attained using concentrations far exceeding those reached in man.