ðə ɹˈaɪt bˈoːɹdɚɹ ʌvðə hˈɑːɹt ɹˈaɪt mˈɑːɹdʒɪn ʌv hˈɑːɹt ɪz ɐ lˈɔŋ bˈoːɹdɚɹ ɔnðə sˈɜːfɪs ʌvðə hˈɑːɹt, ænd ɪz fˈɔːɹmd baɪ ðə ɹˈaɪt ˈeɪtɹiəm.
The right border of the heart (right margin of heart) is a long border on the surface of the heart, and is formed by the right atrium.