Exam 2 Heart Anatomy Objectives

Location and Function of the Heart

Sits between the spine and the sternum, medial to the lungs, sits right on top of the diaphragm. Pumps blood to keep us alive.

Pulmonary Circuit

Circuits to the lungs and back. Mostly driven by the right side of the heart, specifically the right atrium.

Systemic Circuit

Circuits to the rest of the body and back. Driven mainly by the left side of the heart. Also includes the heart muscle.

Location and function of the Pericardium

The pericardium is the serous membrane that lines the pericardial cavity, which surrounds the heart.

Restricts filling of the heart. A heart that gets too large can cause damage. The pericardium stops it from filling too much.

visceral pericardium (epicardium)

covers the outer surface of the heart (deepest layer)

parietal pericardium

lines the inner surface of the pericardial sac (fibrous pericardium.

3 Layers of the heart

epicardium, myocardium, endocardium

Epicardium

covers outside of the heart. Also, the visceral pericardium

Myocardium

Cardiac Muscle

Endocardium

a thin layer that lines the inside of the heart.

Coronary Circulation

blood flow to and from the heart muscles

Coronary Arteries

The right coronary artery comes from the ascending aorta towards the right side of the heart.

R. Coronary artery branches: marginal artery, posterior interventricular artery.

The left coronary artery comes from the ascending aorta towards the left side of the heart.

L. Coronary artery branches: circumflex, anterior interventricular artery.

Cardiac Veins

Small

Middle

Great

All join in the coronary sinus posteriorly and drain into the right atrium

Location of cardiac veins

Small: next to the marginal artery

Middle: posteriorly, next to the posterior interventricular artery in the posterior interventricular sulcus

Great: next to the anterior interventricular artery in the anterior interventricular sulcus

Pathway of coronary circulation

Ascending aorta - right coronary artery - marginal artery - posterior interventricular artery

Veins:

Great vein runs with anterier - coronary sinus

Middle vein - coronary sinus

small - coronary sinus

Ascending aorta - left coronary artery - circumflex artery - anterior interventricular artery

Pathway of blood through the heart

superior vena cava, inferior vena cava, coronary sinus, right atrium, Right A-V tricuspid valve, right ventricle, pulmonary semilunar valve, pulmonary trunk, R. L. pulmonary arteries, lungs, pulmonary veins R. and L. Pairs, left atrium, Left A-V mitral valve, left ventricle, aorta

Anatomical Differences between Atria and Ventricles

The atria have less muscle and are superior to the ventricles. The ventricles has more muscle due to pumping out to the body.

Differences between R. and L. Ventricles

L. ventricle has more muscle because it pumps blood to the Aorta to pump our to the body. (head and limbs)

R. Ventricle has less muscle than the left due to it pumping blood through the pulmonary trunk straight to the lungs, needing less muscle.

Semilunar

Separates a ventricle from a blood vessel

A-V Valves

Separates an atrium from a ventricle

Describe what occurs when a heart valve prolapses and the effect it has on the heart's function.

One or more valve cusps are pushed back into the atrium when the ventricle retracts, causing blood leakage back into the atrium.

Chordae Tendineae

Attaches the A-V valves to the heart wall

Papillary Muscle

Anchors the chordae tendineae to the heart wall

What are the two anatomical differences in the fetal heart, and what is the fate of the structures after they are born?

Foramen Ovale (fetal): a hole in the interatrial wall in the fetal heart. Bypasses the lungs.

Fossa Ovalis (post partum): shallow depression on the interatrial wall

Ductus arteriosus (fetal): blood vessels connecting the fetal pulmonary trunk and the aorta. Bypass the lungs because you aren't breathing air

Ligamentum arteriosum (post partum): remains of the ductus arteriosus

Describe the general deleterious effects of congenital heart defects.

Patent ductus arteriosus: still open, and blood can still travel from the pulmonary trunk to the aorta. limits blood to the lungs

Patent oval foramen: Right atrium to left atrium bypassing the lungs.

Ventricular septal defect: a hole in the wall between the ventricles, by passing the lungs.

Ventricular hypertrophy: The Lost ventricular volume can't fill it as much. Less blood means less blood oxygen.

the first three LOWER ARTERIAL BLOOD OXYGEN

Tetralogy of Fallot

R. ventricular hypertrophy: right ventricle is getting super big, trying to push blood through the valve.

Ventricular septal defect

Pulmonary valve stenosis: a narrow pulmonary valve, harder to get blood through it

Shifted location of the aorta (just superior to the septal defect)

LV Hypertrophy - Concentric: Maladaptive

Hypertension, congenital heart defects, stenosis, etc

Increased muscle mass, but not an increase in ventricular volume

LV Hypertrophy - Eccentric: "athlete's heart"

Results from increased physical activity or pregnancy

Risks are associated with dramatic hypertrophy

Stronger walls and greater blood volume take less to pump.

Cardiomyopathy

Thinning the ventricular wall decreases stroke volume

Effects: wall stretched out, decrease of force, which decreases organ performance

Heart Fibrosis

Causes: results of chronic inflammation and age

metabolic syndrome

Can affect heart muscles and or valves

Valves are often the tricuspid valve. (heart murmurs)

Fibrosus Myocardium Relaxes slowly, never fully relaxes, which doesn't allow as much blood to refill, causing less blood to come out, less oxygen.