Stenosed veins don’t come from Mars and Vasospasm don’t come from there either.

“New perspectives on the role of magnesium in the pathophysiology of the cardiovascular system. II. Experimental aspects.” , Altura BM, Altura BT, Magnesium 1985

“...This divalent cation may also be important in the etiology of a variety of disorders which have vasospasm in common. Evidence is reviewed to support the concept that Mg2+ is a naturally occurring or mimic weak Ca2+ antagonist, which should be useful in the treatment of several types of cardiac and vascular disorders.” https://www.ncbi.nlm.nih.gov/pubmed/3914581/