We report on a giant basilar tip aneurysm in a 48-year-old woman that could not be clipped despite temporary occlusion of the basilar trunk. Adenosine induced cardiac asystole reduced the aneurysm's wall tension and coupled with increased exposure resulting from brain relaxation allowed for the aneurysm to be satisfactorily occluded via an extended right pterional craniotomy. In difficult vascular cases, adenosine induced cardiac standstill is a useful technique which may allow for technical success when other methods such as temporary clipping fail. It acts to both reduce aneurysm wall tension and increase operative exposure by reducing vascular, and hence brain volume.