The ventricular portion, thin and sharp, is named the acute margin; it is nearly horizontal, and extends from the sternal end of the sixth right coastal cartilage to the apex of the heart.
ðə vɛntɹˈɪkjʊlɚ pˈoːɹʃən, θˈɪn ænd ʃˈɑːɹp, ɪz nˈeɪmd ðɪ ɐkjˈuːt mˈɑːɹdʒɪn; ɪɾ ɪz nˌɪɹli hˌɔːɹɪzˈɔntəl, ænd ɛkstˈɛndz fɹʌmðə stˈɜːnəl ˈɛnd ʌvðə sˈɪksθ ɹˈaɪt kˈoʊstəl kˈɑːɹɾɪlɪdʒ tə ðɪ ˈeɪpɛks ʌvðə hˈɑːɹt.