Cardiac dominance is determined by coronary aery
Cardiac dominance is determined by posterior inter ventricular aery which supplies postero inferior pa of interventricular septum. Mostly this a branch of RCA so right cardiac dominance(65% of population) If posterior inter ventricular aery arise from left coronary aery, then it is left cardiac dominance in 10% of population(bad prognosis) Multiple PIVA one from right side one from left side that is co -dominance in 25% of population.