CARDIO: Anatomy and Physiology

Question 1

What side of the heart is the mitral valve?

Answer 1

Left

Question 2

How does mitral valve stenosis lead to pulmonary edema?

Answer 2

Mitral valve stenosis → increase in left atrial pressure → backup of blood into lungs → increased pulmonary capillary pressure → cardiogenic pulmonary edema

Question 3

Pulmonary edema is expected with _____ failure.

Explain how using anatomy

Answer 3

Left Ventricular

Left ventricular hypertrophy (due to increased demand from increased afterload)–> increased Left atrial pressure–> congestion of pulmonary veins–> backup of blood into lungs → increased pulmonary capillary pressure; → cardiogenic pulmonary edema (presenting with orthopnea) and increased pulmonary artery pressure

Question 3

You are about to enter the operating suite, where BC, a 52-year-old male with atrial fibrillation, is about to undergo emergency surgery. He presented to the emergency department after 3 hours of acute midabdominal pain, nausea, and vomiting. When the surgical field is exposed, you notice ischemic damage to BC’s ilium.
What major artery did the embolus likely travel?

Answer 3

superior mesenteric artery

Question 4

What supplies supplies the esophagus to the proximal duodenum?

Answer 4

celiac artery

The celiac trunk supplies embryonic foregut derivatives, from the esophagus all the way down to the proximal duodenum. It also supplies some accessory organs, including the gallbladder, liver, pancreas, and spleen.

Question 5

What does the SMA supply?

Answer 5

The superior mesenteric artery (SMA) supplies midgut derivatives, from the distal duodenum to the proximal two-thirds transverse portion of the colon.

Question 6

What supplies hindgut derivatives, from the distal third of the transverse colon to the upper portion of the rectum?

Answer 6

Inferior mesenteric Artery

Question 7

How does venous blood that returns from the gonads to the heart differ on the right and left sides?

Answer 7

On the right side, venous blood flows from the right gonadal vein directly into the IVC. On the left side, the venous blood flows through the left gonadal vein into the left renal vein and then into the IVC.

Question 8

What is the major difference between the hepatic vein vs hepatic portal vein?

Answer 8

Portal vein is formed by merged veins draining the intestines (mesenteric veins) as well as the stomach (gastric veins), spleen (splenic vein), and pancreas (pancreatic vein). This blood needs to be filtered

Once detoxed, that blood drains to the hepatic vein which feeds into the IVC

Question 9

The two main veins that transport blood back to the right heart are the

Answer 9

superior vena cava (SVC) and inferior vena cava (IVC).

Question 10

CO2-filled blood is conveyed back to the right atrium, passes into the right ventricle, is sent to the lungs through the

Answer 10

pulmonary artery

Question 11

oxygenated blood is sent back to the heart through the__________ as well as the__________ which both drain into the _______.

Answer 11

oxygenated blood is sent back to the heart through the right pulmonary vein (E) as well as the left pulmonary vein, which both drain into the left atrium.

Question 12

Right suprarenal vein drains into __________

Answer 12

drains directly into the inferior vena cava

Question 13

On the left you have the _______ vlave and the _______ valve

Answer 13

Aortic and mitral

Question 14

on the right you have the _____ valve and the ______ valve

Answer 14

tricuspid and pulmonary

Question 15

Oxygen-depleted blood returning from the venous system enters the atrium via the

Answer 15

svc

Question 16

Which AV valve has 2 leaflets and which has 3?

Answer 16

the tricuspid valve on the right (three leaflets) and the bicuspid mitral valve on the left (two leaflets).

Question 17

fibrous cords in the ventricles that connect the AV valves to the papillary muscles.

Answer 17

Chordae tendinae

Question 18

_____________________is a common cause of papillary muscle rupture, which usually occurs 2 to 7 days post-MI (1%-5% of patients). This is a surgical emergency and has a very high mortality rate in patients who experience complete rupture.

Answer 18

Myocardial infarction

Question 19

How long after an MI is a papillary mm rupture most likely to occur?

Answer 19

2-7 days post MI

Question 20

What valves are open and which are shut during diastole?

Answer 20

AV valves are open to allow filling of the ventricles from the atria (see Figure 6). During this time, the semilunar valves remain shut.

Question 21

What phase are the AV valves closed so that all the blood flows out through the semilunar valves to the systemic and pulmonary circulations and not backward into the atria?

Answer 21

cardiac systole

Question 22

What structure keeps the AV valves closed during systole?

Answer 22

The chordae tendineae, which are tendons that connect the AV valves to the papillary muscles, keep the valves closed during systole.

Question 23

How might mitral stenodid lead to dysphagia?

Answer 23

A woman’s enlarged LA, the most posterior structure of the heart, is extrinsically pressing on her esophagus, which causes her difficulty with swallowing. You correctly identify this structure and postulate that anything increasing LA pressure will result in LA enlargement. For KS, the cause of the increase in LA pressure and resultant LA enlargement is mitral stenosis.

Question 24

The right border of the heart on an x-ray of the chest is primarily formed by which structure?

Answer 24

RA

Question 25

Because the coronary arteries emerge distal to the aortic valve, aortic stenosis (narrowing of the valve) will limit circulation to the periphery but also to the coronary arteries and can cause __________

Answer 25

angina

Question 26

How might aortic stenosis lead to angina?

Answer 26

Because the coronary arteries emerge distal to the aortic valve, aortic stenosis (narrowing of the valve) will limit circulation to the periphery but also to the coronary arteries.

Question 27

The LCA supplies what general structures of the heart?

Answer 27

The LCA and its branches supply the left atrium (LA) and left ventricle (LV), as well as most of the interventricular septum.

Question 28

The LCA branches into the ______ and the ______

Answer 28

Left anterior descening and left circumflex artery

Question 29

What main artery supplies the SA node?

Answer 29

Right Coronary artery

Question 30

What supplies the AV node?

Answer 30

The posterior descending/interventricular artery (PDA) originates from the RCA in most individuals to supply the atrioventricular (AV) node

Question 31

Why might anatomical variation in coronary arteries matter?

Answer 31

Patients with right-dominant circulations have better outcomes after percutaneous coronary intervention (angioplasty), an interventional treatment for myocardial infarction.

First is a variation in artery dominance, meaning which coronary artery gives rise to the PDA. Most people (~85%) have a right-dominant coronary artery, meaning that the PDA is a branch of the RCA. The remainder of the population has either left-sided dominance, meaning the LCX gives rise to the PDA, or a codominant circulation, where RCA and LCA combine to give rise to the PDA.

Question 32

There are three primary veins (great, middle, and small) that drain the blood flow from the heart into the ____________, where the veins coalesce at the back of the heart within the coronary sulcus

Answer 32

coronary sinus

Question 33

A 59-year-old male with diabetes and hypertension develops a severe atherosclerotic occlusion of his left circumflex artery. Which of the following structures would be most deprived of oxygen by this occlusion?
Interventricular septum
LA
RA
RV
SA node

Answer 33

Left Atrium

The left circumflex artery (LCX) is a branch of the left coronary artery, traveling posteriorly to supply the left atrium and the left ventricle, so both may become damaged by lack of blood flow in the LCX.

Question 34

In most of the population, which coronary artery gives rise to the posterior descending artery?

Answer 34

The correct answer is right coronary artery (D). Most the population has a dominant right coronary artery (RCA). This means that the posterior descending artery (PDA) is a most common a branch of the RCA.

Question 35

Sometimes, too much pericardial fluid (or blood) can accumulate in the pericardial space, a condition known as pericardial effusion. What are some causes of this?

Answer 35

possible causes include cancer, cardiac surgery, trauma, and infections.

Question 36

The sinoatrial (SA) node, known as the pacemaker of the heart, resides within the ____________________

Answer 36

right atrium, close to the entrance of the SVC.

Question 37

How do the cells of the conduction system differ from their surrounding myocytes?

Answer 37

The cells of the conduction system do not contain intercalated discs and instead communicate directly with one another via gap junctions. Because Purkinje fibers are not contractile, they don’t require the fascia adherens or macula adherens junctions to keep the cells stuck together.

Question 38

In a fetus, what structures bypass pulmonary circulation?

Answer 38

the foramen ovale and the ductus arteriosus.

the maternal placenta delivers oxygenated blood to the fetus through the umbilical vein (see Figure 1, left). Once in the fetus, this blood bypasses the liver (through the ductus venosus) on its way to the right atrium (RA). Because the lungs do not function in the fetus, two structures exist to bypass the pulmonary circulation, the foramen ovale and the ductus arteriosus. Oxygenated blood leaves the left ventricle (LV) and circulates via the systemic circulation to supply the fetal tissue.

Question 39

What vascular structures make fetal circulation unique?

Answer 39

Three fetal blood vessels (umbilical vein and two umbilical arteries) and three fetal shunts (ductus venosus, foramen ovale, and ductus arteriosus) are unique to the fetal circulatory system.

Question 40

What is the functional purpose of the foreamen ovale?

Answer 40

Helps bypass the lungylunglungs

Most of this highly oxygenated blood is shunted directly from the right to left atrium (LA) through the foramen ovale, allowing this oxygenated blood to bypass the nonfunctional fetal lungs and more quickly enter the systemic circulation via the LV and aorta. Hemodynamically, this shunting is caused by high pulmonary vascular resistance, which both increases the pressure in the RA and decreases the pressure in the LA, thus creating an atrial pressure gradient. The diversion of blood through the foramen ovale is a right-to-left shunt, meaning that blood flows directly from the right side to the left side of the heart.

Question 41

How does deoxygenated blood bypass the lungs?

Answer 41

The ductus arteriosis.

This is a small blood vessel connecting the pulmonary artery to the proximal descending aorta. Like the foramen ovale, its purpose is to shunt blood away from the lungs and directly into the systemic circulation. This flow occurs because the high pulmonary vascular resistance blocks most blood from flowing into the lungs, instead shunting it through the ductus arteriosus into the systemic circulation. This deoxygenated blood mixes with the oxygenated blood in the descending aorta and is then carried to the organs.

Question 42

What keeps the ductus arteriosus open in utero?

Answer 42

Prostaglandins (PGE1 and PGE2) produced by the placenta and the ductus itself, plus the relatively low oxygen saturation of the fetal blood passing through it

Question 43

Preload

Answer 43

Preload
The extent to which heart muscle fibers are stretched before the onset of systole. Preload is directly related to end-diastolic pressure and end-diastolic volume.

Question 44

Preload is directly related to ______________________________ and ________________________________

Answer 44

Preload is directly related to end-diastolic pressure and end-diastolic volume.

Question 45

Afterload

Answer 45

The force against which the ventricle contracts to eject blood during systole. Afterload is primarily determined by the blood pressure in the aorta, which is influenced by total peripheral resistance.