Which of the following best describes the effect of calcium ions on the myocardium?: (A) positively inotropic, (B) negatively inotropic, (C) positively chronotropic, (D) negatively chronotropic
Answer is A. Positively inotropic is the best description of the effect of calcium ions on the myocardium.Calcium plays a role in excitation-contraction coupling, and in possible drug effects and heart failure.