I had an mri of the brain which showed a small old left basal ganglia lacunar infarction?

Lacunar Infarct: Lacunar infarcts - a silent stroke that may not produce any outside symptoms. Frequently, patients may be unaware they suffered a lacunar stroke.They result from occlusion of the small penetrating end arteries at the base of the brain usually due to fibrinoid degeneration in contrast to cortical infarcts where embolization of distal thrombus is the main etiology. See a neurologist for consultation.

A risk factor: Regardless of the age of the prior stroke, you need to fully assess all relevant risk factors and start a protective anti-platelet med such as aggrenox, and perhaps lipitor (atorvastatin). Issue is not the prior lacunar infarct, but what may occur in future instead.