chronic microvascular ischemia

I just had a MRI and identified was moderate atrophy with mild changes of chronic microvascular ischemia.  Other impressions were No acute intracanial process and chronic bifrontal subdural hygromas.  

I am wondering if this is related to my heart.  I have had tests that show an irregular heartbeat and sometimes rapid heartbeat.  

Is this related to or does this cause dementia?

Is there anything that I can do to minimize the effects from this?

I have a echogram scheduled for my heart. I am 62 years old and otherwise healthy.  Take no medications and not overweight. Do not exercise as much as I should.  

[Jerry_NJ]

I think your question may be too technical for most readers of this community. It is for me.

As for a connection between dementia and heart rhythm, I've never heard/read of any.