What makes a plaque vulnerable ?
Plaque contents , it’s distribution and consistency make it vulnerable. Soft spots formed by lipids may result in plaque cracks and fissure. Semi solid , mixed , gel like soft plaques are dangerously prone for rupture . Oxidation of LDL, LDL liquefaction and tissue metalloprotinase , thickness of fibrin caps , all promote softening. If none of above mechanism is operative in a given patient , the plaque becomes stiff and hard.
Calcification is the ultimate in hardening . Calcified plaque is resistant to mechanical deformation.If stiff plaques are less vulnerable , hard plaques ( ie calcified plaques ) must be least vulnerable . Calcification can be called an end result of coronary atherosclerosis.
So , calcified coronary artery can be referred to as a failed mission of atherosclerosis .It is equivalent to death of atherosclerosis and denotes the end process of this dreaded disease process.