Human heart is a vital bundle of muscle weighing about 300-400 grams. The blood supply of this muscle mass is highly variable . Some areas are abundantly vascularised ( eg -IVS.) Some areas have a balanced blood supply or twin blood supply (Often the LCX and RCA in the crux of the heart ). Certain areas have a precarious blood supply . They are some times called as water shed areas or the vulnerable (The Bermuda triangle of the heart ) overlapping zones of of LV apex, LV free wall and the anterior surface. This is often a no man’s land .Every major arterial branch ignores this area and shrug of their responsibility .
This is the reason ventricular free wall and IVS rupture is more common in this area making the mechanical complication a leading cause of mortality in STEMI.
Similarly , even among the survivors , this area is more prone for aneurysmal dilatation and adverse remodelling .Though . this is related more to the LV stress distribution (Laplace law) , early softening due to watershed infarct of LV apical zone , also play a major role .
