Marieb Chapter 18 The heart – Flashcards

The myocardium receives its blood supply from the coronary arteries.

Cardiac muscle has more mitochondria and depends less on a continual supply of oxygen than does skeletal muscle.

Anastomoses among coronary arterial branches provide collateral routes for blood delivery to the heart muscle.

Congestive heart failure means that the pumping efficiency of the heart is depressed so that there is inadequate delivery of blood to body tissues.

Tissues damaged by myocardial infarction are replaced by connective tissue.

The left side of the heart pumps the same volume of blood as the right.

Chronic release of excess thyroxine can cause a sustained increase in heart rate and a weakened heart.

Arterial blood supply to the heart muscle is continuous whether the heart is in systole or diastole.

Trabeculae carnae are fond in the ventricles and never the atria.

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.

Autonomic regulation of heart valve is via two reflex centers found in the pons.

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.

An ECG provides direct information about valve function.

As pressure in the aorta rises due to atherosclerosis, more ventricular pressure is required to open the aortic valve.

Proxysmal atrial tachycardia is characterized by bursts of atrial contractions with little pause between them.