Chronic release of excess thyroxine can cause a sustained increase in heart rate and a weakened heart. TRUE Arterial blood supply to the heart muscle is continuous whether the heart is in systole or diastole. Chronic release of excess thyroxine can cause a sustained increase in heart rate and a weakened heart. True. The mitral valve has chordae but the. True. The mitral valve has chordae but the. Answer: TRUE 7) Chronic release of excess thyroxine can cause a sustained increase in heart rate and a weakened heart. Answer: TRUE 8) Arterial blood supply to heart muscle is continuous whether the heart is in systole or diastole. 7) Chronic release of excess thyroxine can cause a sustained increase in heart rate and a weakened heart. 8) Arterial blood supply to heart muscle is continuous whether the heart is in systole or diastole. Chronic release of excess thyroxine can cause a sustained increase in heart rate and a weakened heart. t. 11. The lub sounds of the heart are valuable in diagnosis because they provide information about the function of the heart's pulmonary and aortic valves. f. 12. Autonomic regulation of heart rate is via two reflex centers found in the pons. f. 13. An ECG provides direct information about. Doctors will tell you that stress can cause heart problems. This is known to be true. It then stands to reason if someone has chronic pain they are trying to manage, they are more than likely. Yes. With the excess secretion, also known as hypersecretion, of thyroxine (T4) causes an increased heart rate, high blood pressure, possible palpitations, and could lead to heart faliure. Chronic release of excess thyroxine can cause a sustained increase in heart rate and a weakened heart. True. Arterial blood supply to heart muscle is continuous whether the heart is in systole or diastole. False - It's intermittent. Trabeculae carneae are found in the ventricles and never the atria. True. The lub sounds of the heart are valuable in diagnosis because they provide information. The papillary muscles contract after the other ventricular muscles so that they can take up the slack on the chordae tendineae before the full force of ventricular contractions sends blood against the AV valve flaps.