chronotropic
/ˌkrɒnəˈtrɒpɪk/ /ˌkrɒnəˈtrəʊpɪk/Physiology
adjective
Of, relating to, or affecting the rate of muscular contraction, especially of the heart.
Origin
Late 19th century; earliest use found in Proceedings of the American Academy of Arts and Sciences. From chrono- + -tropic, after German chronotrop.