MGA Great Vessels and The Heart

The heart is a

double sided "pump"

The right side of the heart is for

pulmonary circulation

The left side of the heart is for

systemic circulation

The atria are the

receiving chambers

The ventricles are the

pumping chambers

The right atrium receives deoxygenated blood from above the diaphragm via the

superior vena cava

The right atrium receives deoxygenated blood from below the diaphragm via the

inferior vena cava

The valve connecting the right atrium and ventricle is named

the tricuspid valve

The valve connecting the left atrium to the left ventricle is named

the mitral/tricuspid valve

The anterior surface of the heart is also called the

sternal costal surface

The anterior surface of the heart is mostly composed of the

right ventricle

The left pulmonary surface of the heart is mostly composed of

the left ventricle

The diaphragmatic surface of the heart has

both the left ventricle and some of the right ventricle

The right pulmonary surface is composed of

right atrium

The apex of the heart is formed by the

left ventricle

Pericardium is a ________ sac surrounding the heart and proximal great vessels

fibroserous

The pericardium consists of 2 components

- fibrous pericardium

- serous pericardium

The serous pericardium can be divided into

parietal and visceral layers

The fibrous pericardium is

non-distensible

A rapid accumulation of excess fluid within the pericardial sac will compress the heart (called a _________) resulting in biventricular failure

cardiac tamponade

The phrenic nerves are followed by what vasculature

the pericardiacophrenic vein and artery

The pericardiacopheric artery branches off of the

internal thoracic artery which is a branch of the subclavian artery

The transverse pericardial sinus is located _______ surrounding the aorta and pulmonary trunk

superiorly

The oblique pericardial sinus is located _______ surrounding the pulmonary veins and venae cavae

posteriorly

The transverse pericardial sinus separates

arteries from veins

the oblique pericardial sinus is formed by the reflection of

the pulmonary veins onto the heart

What valve separates the right ventricle and the pulmonary trunk

the semilunar valve

What is the fossa ovalis a fetal remnant of

a R to L shunt

Where is the site of the SA node

crista terminalis superior end near the opening of the SVC

What is the job of the SA node

pacemaker of the heart

Site of the AV node

interatrial septum near the opening of the coronary sinus

Pulmonary valve (semilunar) contains

- anterior semilunar cusp

- right semilunar cusp

- left semilunar cusp

Tricuspid valve contains

- anterior cusp

- septal cusp

- posterior cusp

chordae tendineae

thin bands of fibrous tissue that attach to the valves in the heart and prevent them from inverting

Trabeculae carnae

muscular ridges and columns on inside walls of ventricles

septomarginal trabecula (moderator band)

curved muscular bundle running from inferior part of interventricular septum to base of anterior papillary muscle. Carries part of the right branch of the AV bundle and prevents overdistension

The aortic and pulmonary sinuses fill with blood following ventricular contraction which

forces the cusps to close

The nodules on the semilunar valves

thickened, middle portion on each cusp

Right and left coronary arteries arise from the R and L aortic sinuses, as these fill with blood

the blood is automatically forced into the arteries

Semilunar valves have no ...

papillary muscles or chord tendinae

During the ventricular contraction (systole), the AV valves are

CLOSED

During ventricular contraction (systole), the semilunar valves are

OPEN

During ventricular relaxation (diastole), the A/V valves are

OPEN

During ventricular relaxation (diastole), the semilunar valves are

CLOSED

Where do you listen to the pulmonary valve at?

medial end of the left second intercostal space (LUSB)

Where do you listen to the aortic valve?

medial end of the right second intercostal space (RUSB)

Where do you listen to the mitral valve?

left 5th intercostal space (over apex of heart) along midclavicular line (5LICS)

Where do you listen to the tricuspid valve?

left of the sternum near 4-5th intercostal space (4LICS)

The wall of the ___ ventricle is 3-4x as thick compared to the wall of the other

left

Foramen ovale

allows oxygenated blood entering the RA to pass directly into the LA to bypass the nonfunctional fetal lungs

What does the foramen ovale become

fossa ovalis

Ductus arteriosus

connects pulmonary trunk with arch of aorta, allowing fetal blood to bypass the lungs

What does the ductus arteriosus become

ligamentum arteriosum

What has the highest O2 in fetal circulation

umbilical vein, coming from the placenta

Fetal circulation

Placenta --> umbilical vein --> ductus venous (shunt in liver) --> foramen ovale

The coronary sulcus

groove that marks border between atria and ventricles

The interventricular groove

separates the ventricles

Right coronary artery branches

- atrial branch

- right marginal branch

- posterior interventricular branch

Left coronary artery branches

- anterior interventricular branch

- circumflex branch (*left marginal branch)

Right dominant coronary artery

posterior interventricular artery arises from RCA

Left dominant coronary artery

posterior interventricular artery arises from circumflex branch of LCA

Distribution of RCA

RA, SA and AV nodes, and posterior part of IVS

Distribution of LCA

most of LA and LV, IVS, and AV bundles, may supply AV node

Distribution of right marginal branch

RV and apex of heart

Distribution of posterior interventricular branch

RV and LV and posterior 1/3 of IVS

Distribution of anterior interventricular branch

RV, LV, and anterior 2/3s of IVS

Distribution of circumflex branch

LA and LV

Distribution of left marginal branch

LV

Middle cardiac vein runs with

the posterior interventricular branch

Small cardiac vein runs with

the right marginal branch

Great cardiac vein runs with the

left anterior descending branch

Anterior cardiac veins drain directly into the

right atrium

Middle cardiac vein drains into the

coronary sinus

Coronary artery occlusion

aka an MI

Most common artery involved in an MI is the

anterior interventricular branch (IV branch) (40-50%)

Right coronary artery blockages happen in about

30-40% of MIs

Circumflex branch occlusions happen in about

15-20% of MIs

Cardiac conduction system

SA node --> AV node --> AV bundle (Bundle of His) --> RBB and LBB --> Purkinje fibers

Cardiac innervation

autonomic nervous system through the cardiac plexus

The cardiac plexus

regulates HR, force of contraction, and cardiac output

Parasympathetic stimulation of the heart

dec HR, reduced force of cardiac contraction, and constricts the coronary arteries

Sympathetic stimulation of the heart

inc HR, and force of contraction

Coronary artery disease is seen where the heart muscle receives an

insufficient blood supply due to narrowing to vessels

Narrowing of vessels in coronary artery disease due to

atherosclerosis, artery spasm, or a clot

Treatment of coronary artery disease

drugs, bypass graft, angioplasty, and stent

MI

death of area of heart muscle due to lack of O2, results depend on size and location of damage

Angina pectoris

heart pain from ischemia of cardiac muscle

What is a CABG

coronary artery bypass graft

Coronary angioplasty