Echo quiz 1

What is automaticity?

Property of cardiac cells that generates spontaneous action potentials to create electrical impulses

How is the electrical impulse created in the body?

By moving electrolytes across cell walls via a sodium-potassium pump

What is Phase 0 of the action potential curve (APC)?

1. Depolarization

2. Open sodium channels produce sodium influx

3. Inside of cell = POSITIVE

4. Outside of cell = NEGATIVE

What is Phase 1 of the action potential curve (APC)?

1. Closed sodium channels reduce sodium influx

2. Open potassium channels produce potassium influx

3. Inside of cell = LESS POSITIVE

4. Outside of cell = NEGATIVE

What is Phase 2 of the action potential curve (APC)?

1. Sodium influx is completely stopped

2. Calcium influx begins via slow channels

What is Phase 3 of the action potential curve (APC)?

1. Repolarization or recovery - cell returning to ready state

2. Open potassium channels cause potassium to leave cell

3. Inside of cell = NEGATIVE

4. Outside of cell = POSITIVE

What is Phase 4 of the action potential curve (APC)?

1. Refractory

2. Open channels cause sodium to leave cell

3. Open channels cause potassium influx

What determines the degree of contraction during an action potential?

Amount of calcium

What is adenosine triphosphate (ATP)?

Molecule that supplies energy for action potential to take place

Identify this image.

1. P wave

2. Q wave

3. R wave

4. S wave

5. T wave

How are the EKG and action potential waveforms related?

1. P wave: Atrial depolarization

2. Hidden QRS wave: Atrial repolarization

3. QRS: Ventricular depolarization

4. T wave: Ventricular repolarization

Blood flows from areas of ___ pressure to areas of ___ pressure.

High; Low

Where is HIGH pressure located in the heart?

Left side

Where is LOW pressure located in the heart?

Right side

(T/F) Each ventricle expels the SAME VOLUME of blood per beat.

True

Identify this image.

1. RA

2. RV

3. SA node

4. AV node

5. Bundle of HIS

What is the average resting heart rate?

75 bpm

How long does each cardiac cycle take?

0.8 seconds

What is the role of the right and left atrium during systole?

Atrial contraction forces blood into ventricles

What is the role of the right and left atrium during diastole?

Atrial relaxation allows blood to fill ventricles

What is the role of the AV valves during systole?

Valves close to prevent backflow of blood into atria

What is the role of the AV valves during diastole?

Valves open to allow blood to flow from atria to ventricles

What is the role of the right and left ventricle during systole?

Ventricular contraction pushes AV valves closed

What is the role of the right and left ventricle during diastole?

Ventricle relaxation allows blood to fill ventricles

What is the role of the semilunar valves during systole?

Valves open so blood can enter great vessels

What is the role of the semilunar valves during diastole?

Valves close to prevent backflow of blood into ventricles

How are the EKG and phases of cardiac cycle waveforms related?

1. P wave: Atrial systole and mid-to-late ventricular diastole

2. QRS wave: Atrial diastole and ventricular systole

3. T wave: Early ventricular diastole

How are the EKG and pressure curve waveforms related?

1. P wave: Ventricular filling or when ventricular pressure drops below atrial pressure (brief moment all valves closed)

2. QRS: Isovolumetric contraction or when volume is constant and ventricular pressure increases (brief moment all valves closed)

3. T wave #1: Ventricular ejection or when ventricular pressure surpasses great vessel pressure and blood is ejected from heart

4. T wave #2: Isovolumetric relaxation or when volume is constant and ventricular pressure decreases (brief moment all valves closed)

What are the phases of ventricular filling?

1. Rapid ventricular filling

2. Diastasis or when flow slows due to equal AV pressures

3. Slow filling (atrial kick/contraction) or when SA node sends impulse causing atrial contraction

What is end diastolic volume (EDV)?

When small traces of blood (120 mL) are left in each ventricle after ventricular diastole

What is end systolic volume (ESV)?

When small traces of blood (50 mL) are left in each ventricle after systole

What is stroke volume (SV)?

Amount of blood ejected per beat

What is the average stroke volume (SV)?

70 mL

What is the formula for stroke volume (SV)?

SV = EDV - ESV

What is preload?

Stretch of heart before it contracts due to blood filling ventricles

What is the Frank-Starling law?

1. Describes how preload is related to force of contraction

2. Example: High preload from high volume of blood filling ventricles during diastole = Strong contraction during systole

What is contractility?

Forcefulness of contraction

What is afterload?

Amount of pressure that must be exceeded for ventricular contraction to occur that is dependent on systemic and pulmonic vascular resistance

What is cardiac output (CO)?

Amount of blood pumped out of heart in one minute that is determined by stroke volume and heart rate

What is the normal value for cardiac output (CO)?

4 - 8 L/min

What is the equation for cardiac output (CO)?

CO = SV x HR

(T/F) Echo is the only way to determine cardiac pressure.

False; Only way to determine cardiac pressures is by heart catheterization

What is the normal range of right heart pressures?

1. Right atrial pressure (RAP): 0-6 mmHg

2. Right ventricular systolic pressure (RVSP): 15-25 mmHg

3. Right ventricular diastolic pressure (RVDP): 8-15 mmHg

4. Pulmonary artery systolic pressure (PASP): 15-25 mmHg

5. Pulmonary artery diastolic pressure (PADP): 8-15 mmHg

6. Pulmonary capillary wedge pressure (PCWP): 6-12 mmHg

What is the normal range of left heart pressures?

1. Right atrial pressure (LAP): 8-12 mmHg

2. Left ventricular systolic pressure (LVSP): 90-140 mmHg

3. Left ventricular diastolic pressure (LVDP): 10-16 mmHg

4. Aorta systolic pressure (ASP): 90-140 mmHg

5. Aorta diastolic pressure (ADP): 60-90 mmHg

What is blood pressure?

Amount of blood exerted by blood on walls of vessel that is generated by
ventricular contractions

What is normal blood pressure?

120/80

What blood pressure values constitute for an emergency?

1. Hypertension: Over 180/120

2. Hypotension: Under 90/60 with symptoms

What is auscultation?

Listening to sounds from heart, lungs, or other organs with a stethoscope

What are the parts of a stethoscope that can be placed on the patient?

1. Diaphragm: Transmits higher frequency sounds

2. Bell: Transmits lower frequency sounds

What are the normal heart sounds and what do they indicate?

1. S1 “lub”: Closure of AV valves

2. S2 “dub”: Closure of semilunar valves

What is a heart murmur?

Blowing, whooshing, or rasping sound heard during a heartbeat caused by turbulent (rough) blood flow through heart valves or near heart

How many chambers does the heart have?

4

(T/F) The thickness of muscular walls varies depending on the chamber.

True

What is the normal heart rate?

60-100 contractions per minute

Where is the heart located?

Posterior to sternum within middle mediastinum

What angle does the heart lie at?

45 degrees towards left side between third and fifth intercostal space

What is the apex of the heart?

Cone or bottom of heart that consists of tip of left ventricle and rests on diaphragm below seventh rib

What is the base of the heart?

Top of heart that consists of atria and great vessels

What are the great vessels?

1. Aorta

2. Pulmonary artery

What makes up the superior border of the heart?

1. Right atrium

2. Left atrium

What makes up the inferior or diaphragmatic border of the heart?

1. Most of right ventricle

2. Small portion of left ventricle

What makes up the right border of the heart?

Right atrium

What makes up the left border of the heart?

1. Left ventricle

2. Small portion of left atrium

What makes up the anterior border of the heart?

1. Right ventricle

2. Small portion of right atrium

3. Small portion of left ventricle

What makes up the posterior (spine) border of the heart?

1. Left atrium

2. Left ventricle

What is the pericardium?

Thin sac that houses heart and roots of great vessels

What are the two layers of the pericardium?

1. Parietal

2. Visceral

What is located within the pericardial cavity?

10-20 mL of serous fluid used to lubricate for smooth contractions

What is the IV sulcus?

Part of cardiac skeleton that separates right ventricle and left ventricle externally

What is the AV sulcus?

Part of cardiac skeleton that separates left atrium and left ventricle externally

What is the coronary sulcus?

Part of cardiac skeleton that separates right atrium from right ventricle externally

What is the crux of the heart?

Posterior portion of heart where all 4 chambers meet

What is the function of the crux of the heart?

Determines dominance of heart by which coronary artery feeds which portion

How is dominance determined in the heart?

1. Right dominance is fed by right coronary artery

2. Left dominance is fed by left coronary artery

What is the epicardium or visceral layer of the heart?

Outermost layer composed of epithelial cells

What is the myocardial layer of the heart?

Middle layer composed of muscle fibers and cells that are responsible for contraction

What is the endocardial layer of the heart?

Innermost layer that is composed of simple squamous cells, lines inside of myocardium, and covers valves and tendons

What is the posterior portion of the right atrium?

Smooth walled portion where IVC and SVC enter heart and is derived from embryonic sinus venosus

What is the anterior portion of the right atrium?

Thin walled and trabeculated portion which is original embryonic right atrium

What is the crista terminalis?

Muscular ridge that internally separates two portions of right atrium

What is the sulcus terminalis?

Portion of heart that externally separates anterior and posterior portions of right atrium

What is the right atrial appendage or auricle?

Hollow, triangular shaped area located along free wall of right atrium that is lined by pectinate muscle

What is a Eustachian valve?

Normal variant in right atrium that presents as a functional valve in fetus that covers IVC

What is the Chiari Network?

Normal variant in right atrium that presents as a fine mobile fiber near IVC and often extends to crista terminalis

What is a prominent crista terminalis or terminal ridge?

Normal variant in right atrium that presents as a mass when prominent

What is the main function of the right ventricle?

Maintain pulmonary circulation by sending deoxygenated blood to lungs

What is the right ventricular inflow tract (RVIT)?

Part of right ventricle composed of tricuspid valve and its apparatus that contains trabeculated walls

What is the right ventricular outflow tract (RVOT) or infundibulum?

Part of right ventricle located below pulmonic valve that contains smooth walls

What are the inflow and outflow tracts of the right ventricle separated by?

1. Parietal band

2. Septal band

3. Moderator band

What is the moderator band?

Tissue that extends from anterior free wall of right ventricle to IVS and provides a quick path for conduction system to reach ventricular wall

Where is the moderator band best visualized?

A4C

What is the main function of the left atrium?

Receiving oxygenated blood from pulmonary veins

What is the anterior portion of the left atrium?

Thick left atrial appendage used to store blood

What is the posterior portion of the left atrium?

Smooth walled portion where pulmonary veins enter

What is the left atrial appendage?

Small finger-like outpouching of muscular wall of left atrium that moderates intravascular volume

(T/F) The left atrial appendage is typically seen transthoracically.

False; Left atrial appendage is most commonly seen through TEE

Where is the left atrial appendage visualized best?

1. PSAX basal

2. A4C

Why is it important to check for a clot in the left atrial appendage?

Left atrial appendage played role in TIA and stroke in those with atrial fibrillation

What is the main function of the left ventricle?

Pump oxygenated blood through aorta to rest of body

(T/F) The left ventricle is the main pumping chamber of the heart.

True