Term
| The anatomical path of conduction within the heart is: |
|
Definition
| SA node - Atrial Muscle & AV Node - AV Bundle - AV Bundle Branches (left and right) - Purkinje Fibers - Ventricular Muscle |
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Term
| The three purposes of the AV node are: |
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Definition
1. Limit fibrillation entry into ventricles
2. back-up pacemaker
3. delays action potentials to maximize ventricular filling. |
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Term
| Purkinje fibers conduct rapidly due to what ion channel? |
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Definition
|
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Term
| During Phase 0 of ventricular muscle activation what occurs? |
|
Definition
Influx of Na+
Decreased efflux of K+ |
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|
Term
| During Phase 1 of ventricular muscle activation what occurs? |
|
Definition
Decreasing Na+ influx
Beginning of Na+ removal |
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|
Term
| During Phase 2 of ventricular muscle activation what occurs? |
|
Definition
Efflux of Na+
Increased Influx of Ca2+ |
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|
Term
| During Phase 3 of ventricular muscle activation what occurs? |
|
Definition
Removal of Ca2+
Increased Efflux of K+ |
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|
Term
| During Phase 4 of ventricular muscle activation what occurs? |
|
Definition
| Balance of ion influx and efflux |
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Term
| The potential problem with Na+ channel blockers is: |
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Definition
| The block all Na+ channels, potentially decreasing contractility. |
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Term
| The drug used to block only I-f channels in the SA node is: |
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Definition
| Ivabradine. This lowers the risk of bradycardia. |
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Term
| Sick Sinus Syndrome is characterized by: |
|
Definition
| Abnormal generation of an action potential by the SA node resulting in an inappropriate rate. This causes bradycardia, sinus arrest, sinus node exit block, atrial tachyarrythmias, atrial bradyarrythmias. |
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|
Term
| Sick Sinus Syndrome is treated with: |
|
Definition
|
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Term
| Breeds of dogs that Sick Sinus Syndrome has been reported in include: |
|
Definition
| Mini schnauzers, Dachshunds, Pugs, Westies, Cocker Spaniels, and Boxers. |
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Term
| The normal ion balance results in what intracellular/extracellular charge? |
|
Definition
| Negative intracellular, positive extracellular. |
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|
Term
| The action potential results in what intracellular/extracellular charge? |
|
Definition
| A positive intracellular environment and a negative extracellular environment. |
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|
Term
|
Definition
| A point where two opposite polarities are extremely close. |
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Term
|
Definition
| Current dipoles that are moving down the conduction path. |
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|
Term
| An upward deflection on an ECG is produced by: |
|
Definition
| A depolarization moving toward a positive pole, or a repolarization moving away from a positive pole. |
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|
Term
| A downward deflection on an ECG is produced by: |
|
Definition
| A depolarization moving away from a positive pole, or a repolarization moving toward a positive pole. |
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|
Term
|
Definition
|
|
Term
| The Q,R, and S waves represent: |
|
Definition
| Ventricular Depolarization. |
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|
Term
|
Definition
| Ventricular repolarization. |
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|
Term
|
Definition
| Action potentials to cover the center of the cell. |
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|
Term
| Ryanodine Receptors mediate the release of: |
|
Definition
| Calcium ions through calcium induced calcium release in cardiac muscle. |
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|
Term
| Dilated Cardiomyopathy results from: |
|
Definition
| Defective Ca2+ transport within cardiac muscle - leads to decreased contractility and muscle thinning. |
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|
Term
| Dilated Cardiomyopathy may be treated with: |
|
Definition
| Ca2+ sensitizers (such as pimobendan) |
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|
Term
| Which valves are open during systole? |
|
Definition
| Pulmonic and Aortic valves. |
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|
Term
| Which valves are open during diastole? |
|
Definition
|
|
Term
| Mitral valve disease is characterized by what, and common to which breed? |
|
Definition
| Excessive connective tissue stiffens the valves, preventing them from closing. Common to Cavalier King Charles. |
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|
Term
| Because valve closure is silent, heart sounds are produced by: |
|
Definition
1. Muscle vibration
2. Rapid deceleration of blood. |
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|
Term
| The two heart sounds typically heard on auscultation are: |
|
Definition
1. Closing of mitral and tricuspid valve (occurs with such a small delay sounds like one)
2. Closure of the aortic and pulmonary valve. |
|
|
Term
| Mitral regurgitation affects which heart sounds? |
|
Definition
| S1 is diminished and slurred. S2 is normal. |
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Term
| The percentage of blood that flows into the venticle to fill it due to atrial contraction is: |
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Definition
|
|
Term
| Ejection of blood from semi-lunar valves occurs when: |
|
Definition
| Ventricular pressure exceeds vascular pressure |
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|
Term
| Cardiac Output is a product of: |
|
Definition
| Stroke Volume and Heart Rate |
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|
Term
| Cardiac output in the dog is: |
|
Definition
| 1 - 5 liters per minute depending on breed. |
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|
Term
| Normal Stroke Volume in the dog is: |
|
Definition
|
|
Term
|
Definition
60-140 bpm
180 in small dogs
200 in puppies |
|
|
Term
|
Definition
| The amount of contractions per unit time (heart rate) |
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|
Term
|
Definition
| The force of contractions. |
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|
Term
| SNS regulation of channels is by which receptors? |
|
Definition
| Beta - adrenergic; increases depolarization rate. |
|
|
Term
| PSNS regulation of channels is by which receptors? |
|
Definition
| Cholinergic; results in decreased depolarization rate. |
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|
Term
| The function of SERCA is: |
|
Definition
| It is the primary mover of calcium in myocytes. |
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Term
|
Definition
| Vascular sensors which detect pressure |
|
|
Term
| CHemoreceptors are vascular receptors which detect: |
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Definition
|
|
Term
| Mean Arterial Pressure (MAP) is a product of |
|
Definition
Cardiac Output and Total Peripheral Resistance
CO x TPR |
|
|
Term
| Baroreceptors are primarily found: |
|
Definition
| In the carotids and the aorta. |
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|
Term
Which is the correct order for action potential propagation through the
heart?
a) SA node, AV bundle, AV node, purkinje fibres
b) AV node, AV bundle, SA node, purkinje fibres
c) SA node, AV node, AV bundle, purkinje fibres
d) atrial muscle, AV node, AV bundle, ventricular muscle |
|
Definition
| c) SA node, AV node, AV bundle, purkinje fibres |
|
|
Term
the valve between the left atrium and left ventricle is called the...
a) mitral valve
b) tricuspid valve
c) pulmonary valve
d) aortic valve |
|
Definition
| a) mitral valve (or bicuspid) |
|
|
Term
what cardiovascular effect is not produced by angiotensin II?
a) increased stroke volume
b) increased vasoconstriction
c) increased aldosterone secretion
d) increased heart rate |
|
Definition
|
|
Term
what channel(s) is (are) responsible for the pacemaker potential in
the sinoatrial node?
a) voltage gated sodium channel and potassium channel
b) “funny” channel and potassium channel
c) voltage gated calcium channel and potassium channel
d) “funny channel” and voltage gated calcium channel |
|
Definition
| d) “funny channel” and voltage gated calcium channel |
|
|
Term
why does tachycardia increase the risk of myocardial infarct?
a) tachycardia increases sarcoplasmic reticulum calcium load
b) decreased diastolic perfusion of the myocardium
c) tachycardia disrupts HCN channels in the SA node
d) stroke volume declines as heart rate increases |
|
Definition
| b) decreased diastolic perfusion of the myocardium |
|
|
Term
a patient has a mutation in their ryanodine receptor gene that enhances
Ca2+ binding to site I2. What is the result of that mutation?
a) increased sarcoplasmic reticulum calcium release
b) decreased sarcoplasmic reticulum Ca2+ release
c) increased sarcoplasmic reticulum loading of calcium
d) decreased sarcoplasmic reticulum loading of calcium |
|
Definition
| b) decreased sarcoplasmic reticulum Ca2+ release |
|
|
Term
a functional decrease in ventricular myocyte K+ channels would cause what change on an ECG
trace?
a) prolonged P wave duration
b) prolonged PR interval
c) prolonged QRS duration
d) prolonged QT interval |
|
Definition
|
|
Term
which one of the following statements regarding mode of
transportation in the cardiovascular system is incorrect?
a) the main modes of transportation in the cardiovascular system are bulk flow and diffusion
b) transmural pressure is also called perfusion pressure
c) interstitial fluid is the extracellular fluid outside capillaries
d) the primary function of the cardiovascular system is transport, which includes metabolic
substances and metabolic wastes |
|
Definition
| b) transmural pressure is also called perfusion pressure |
|
|
Term
which one of the following vessel types is know as the compliance vessels?
a) aorta
b) capillaries
c) veins
d) arterioles |
|
Definition
|
|
Term
as blood moves through the vascular system it encounters resistance. Which one of the following
statements is incorrect regarding resistance in the vessels?
a) resistance of blood flow in the vessels produces friction that is dissipated by heat
b) the net resistance of the entire circulation is called total peripheral resistance
c) resistance is inversely proportional to vessel length
d) vasodilation results in a decrease in vessel resistance |
|
Definition
| c) resistance is inversely proportional to vessel length |
|
|
Term
a 6 year old male german shepherd presents with difficulty breathing. Following examination and
workup, you determine the dog to have pulmonary edema secondary to heart failure. The most
significant cause of edema in this patient is likely due to...
a) decreased plasma proteins and oncotic pressure
b) obstruction of the lymphatics
c) increased capillary hydrostatic pressure
d) increased capillary permeability to proteins and interstitial protein concentrations |
|
Definition
| c) increased capillary hydrostatic pressure |
|
|
Term
regarding local hormonal control of vascular tone, bradykinin produces _________, while nitrous
oxide produces__________.
a) constriction, constriction
b) constriction, dilation
c) dilation, dilation
d) dilation, constriction |
|
Definition
|
|
Term
which one of the following vessel types produces the greatest myogenic contractions in response to increases in transmural distending pressure?
a) aorta
b) vena cava
c) venules
d) arterioles
e) large arteries |
|
Definition
|
|
Term
| The two modes of transport used by the cardiovascular system to move substances are: |
|
Definition
|
|
Term
| The primary function of the cardiovascular system is: |
|
Definition
| Transport of metabolic substrates and metabolic wastes. |
|
|
Term
| Bulk Flow is characterized by: |
|
Definition
| Rapid blood movement over long distances, requiring energy created by perfusion pressure. |
|
|
Term
| Perfusion pressure is measured by: |
|
Definition
| inlet pressure - outlet pressure |
|
|
Term
| Transmural pressure is also called ____ and is measured by ____: |
|
Definition
| Distending pressure; internal pressure - external pressure |
|
|
Term
| The driving force of Diffusion as transport is: |
|
Definition
| The concentration gradient. |
|
|
Term
| All metabolically active cells need to be at least how close to a capillary? |
|
Definition
|
|
Term
|
Definition
| There is decreased bulk flow to a tissue. |
|
|
Term
| Infarction is permanent damage resulting from: |
|
Definition
|
|
Term
| Central circulation refers to: |
|
Definition
| Pulmonary plus cardiac circulation. |
|
|
Term
| Coronary circulation refers to: |
|
Definition
| the blood supply to the heart. |
|
|
Term
| The three types of portal systems are: |
|
Definition
1. Hepatic
2. Renal
3. Hypophyseal |
|
|
Term
| The distribution of blood between the systemic and central circulation is: |
|
Definition
Systemic: 75%
Central: 25% |
|
|
Term
| Veins and venules store what percentage of blood: |
|
Definition
|
|
Term
| The "muscular arteries" which generate resistance are known as: |
|
Definition
|
|
Term
| Average BP in the Aorta is |
|
Definition
|
|
Term
| Average BP in the Vena Cava is |
|
Definition
|
|
