Does atropine have a positive or negative inotropic effect on the heart

[Smiley4ever]

I have been looking at different papers but they don't all seem to agree. One paper says stroke volume and cardiac output are decreased after atropine injected, other papers say contractility is increased...I have also read that there is variable change...so I'm not really sure
Thanks!

[ineedanswers]

atropine increases heart rate and decreases the stroke volume(blood ejected by the ventricle per beat) As a result the cardiac out put remains same.
it is because the myocardium contracts at a much faster rate but the force of contraction is greatly reduced thus the cardiac out put remains unchanged.