calcium antagonism is an unifying concept that offers a common denominator for a multitude of beneficial effects in cardiovascular therapy such as : direct reduction of myocardial energy expenditure and oxygen demand , improvement of myocardial oxygen supply resulting from spasmolytic and vasodilator effects on coronary trunk arteries ( including collaterals and anastomoses ) , lowering of systemic arteriolar resistance ( antihypertensive action ) , indirect diminition of cardiac oxygen requirement due to a fall in afterload , cardioprotection by prevention of excessive myocardial ca uptake , damping effects on ectopic cardiac automaticity and on reentry pathways ( not discussed in the present paper ) , and possibly anticalcinotic protection of the arterial walls at an advanced age or in cases of premature arterial senescence due to diabetes , hypertension , or nicotine intoxication .
C0018787
cardiac
C0027061
myocardial