I'm not sure how relevant it is, but there is a theory that all Mammals have a finite number of heartbeats of a similar number no matter what their size (baring from humans, which differ in their improved life styles, living standards and health-care etc.). A mouse, whose heart beats much faster than an elephants (for example) lives for far less time than an elephant, but due to their difference in heart-rate, both have a remarkably similar number of heartbeats in their life-times.
Obviously this doesn't take into account things like cars crashing into you, or sudden trips off of high buildings, but generally speaking it is... well quite frankly remarkable how close the heart-beats are in different mammals (excluding humans). I don't personally have any statistics*, and would rather not bore you all with them anyway, but tis just food for thought :)
(*Heads up: If you are interested, the statistics should be out there- just search for "Finite heart-beats" or something similar)