Lec7 Cardiac Output, Venous Return, and Coronary Circulation

85 fill-in-the-blank practice flashcards covering cardiac output, venous return, muscle blood flow, and ischemic heart disease based on Dr. Cires' lecture.

Cardiac output (CO) is the quantity of blood pumped into the __________ each minute by the heart.

aorta

The quantity of blood flowing from the veins into the right atrium each minute is known as __________.

venous return (VR)

Except for brief periods, venous return and cardiac output must __________ each other.

equal

The major determinant of cardiac output is __________ because the heart pumps what returns to it.

venous return

The major force driving peripheral blood back to the heart is the difference between __________ and right atrial pressure.

venous pressure

The formula for Venous return is $VR = \frac{Venous\,pressure - RA\,pressure}{Venous\,resistance}$.

Venous resistance

Factors that decrease __________ pressure facilitate venous return.

right atrial

During sympathetic activation, increased resistance throughout the body causes an increase in __________, which ultimately cancels out increased venous resistance.

arterial pressure

Veins in the arms and legs have __________ in their walls that only open for upward flow.

one-way valves

The __________ mechanism occurs when skeletal muscles contract and squeeze blood in the veins upward toward the heart.

muscle pump

Increasing the rate and depth of __________ (the respiratory pump) is a way the body raises CO during physical exercise.

breathing

For young, healthy men, resting cardiac output averages about __________ $L/min$.

$$5.6$$

For young, healthy women, resting cardiac output averages about __________ $L/min$.

$$4.9$$

The average cardiac output for the resting adult, in round numbers, is often stated to be about __________ $L/min$.

$$5$$

Normal coronary blood flow is approximately __________ of total cardiac output.

$$5\%$$

Cardiac output per square meter of body surface area is known as the __________.

cardiac index

A normal average cardiac index for adults is about __________ $L/min/m^2$.

$$3$$

The normal adult range for the cardiac index is __________ to __________ $L/min/m^2$.

$2.5$; $4.2$

The cardiac index rises rapidly to a level greater than $4\,L/min/m^2$ at age __________ years.

$$10$$

By age 80, the cardiac index typically declines to about __________ $L/min/m^2$.

$$2.4$$

The __________ is the end-diastolic volume (EDV) or stretch of the heart muscle cells just before contraction.

preload

The resistance or force the ventricle must generate to open the aortic valve is called __________.

afterload

Afterload is primarily determined by arterial blood pressure and __________.

systemic vascular resistance (SVR)

According to the __________, the heart muscle stretches and causes a stronger contraction to eject extra blood when preload increases.

Frank-Starling law

If afterload is too high, such as in severe hypertension, the __________ will decrease, leaving more blood in the ventricle.

stroke volume

The primary controllers of cardiac output are the various factors of the __________ that affect venous return.

peripheral circulation

The myocardial wall has two important properties during systole: contraction and __________ (elastic recoil).

elasticity

Local blood flow in tissues almost always increases when tissue __________ consumption increases.

oxygen

In the formula for long-term CO level, $Cardiac\,Output = \frac{Arterial\,Pressure}{Total\,Peripheral\,Resistance}$.

Total Peripheral Resistance

Conditions like Beriberi and Hyperthyroidism lead to a __________ cardiac output.

high

Hypothyroidism and the removal of both arms and legs are associated with a __________ cardiac output.

low

Three major effects essential for exercise are mass sympathetic discharge, increase in arterial pressure, and increase in __________.

cardiac output

During exercise, the sympathetic nervous system causes __________ in the viscera to redirect blood flow to skeletal muscles.

vasoconstriction

In a nonathlete, CO during exercise must increase to __________ to __________ times normal.

four; five

In a well-trained athlete, CO during exercise can increase to __________ to __________ times normal.

six; seven

At rest, blood flow through skeletal muscle averages __________ to __________ $ml/min/100\,g$ of muscle.

$3$; $4$

During extreme exercise in a well-conditioned athlete, skeletal muscle blood flow can rise to a maximum of __________ $ml/min/100\,g$.

$$400$$

Muscle contraction increases venous return through a __________ response and dilates blood vessels through a chemical response.

mechanical

Local vasodilation of active muscle is stimulated by decreased $PO_2$ and increased __________.

metabolites

The primary controller of coronary blood flow is local __________.

muscle metabolism

The ability of the heart to maintain constant flow despite changes in perfusion pressure is called __________.

autoregulation

Cardiac muscle has a high capillary density of __________ to __________ /mm^2.

$3000$; $4000$

Oxygen extraction in cardiac muscle is high, ranging from __________ to __________ percent.

$60$; $80$

Because of muscle compression, coronary capillary blood flow in the left ventricle falls to a low value during __________.

systole

The outer surface __________ coronary arteries supply most of the muscle.

epicardial

Intramuscular coronary vessels in the __________ plexus of the LV are compressed greatly during ventricular contraction.

subendocardial

In a normal heart, many __________ exist among smaller arteries sized $20$ to $250$ micrometers in diameter.

anastomoses

The __________ supplies mainly the anterior and left lateral portions of the left ventricle (LV).

left coronary artery (LCA)

The __________ supplies most of the right ventricle (RV) and the posterior LV in 80 to 90 percent of people.

right coronary artery (RCA)

Coronary blood flow is regulated mostly by local __________ vasodilation in response to nutritional needs.

arteriolar

In the presence of low oxygen, ATP degrades to __________ and eventually releases adenosine into tissue fluids.

AMP

__________ is a substance with great vasodilator propensity released from heart muscle cells when oxygen is low.

Adenosine

Besides adenosine, other vasodilators include potassium ions, hydrogen ions, carbon dioxide, prostaglandins, and __________.

nitric oxide

Acetylcholine from the __________ nerves slows the heart and indirectly constricts coronary arteries by decreasing metabolism.

vagus

The __________ effect of the sympathetic nervous system is to increase HR and contractility, which indirectly increases coronary blood flow.

indirect

The clinical presentation of CAD where no symptoms are felt despite reduced blood flow is called __________.

silent ischaemia

The acronym ACS stands for __________.

Acute coronary syndromes

Acute coronary syndromes are divided into unstable angina, __________, NSTEMI, and sudden death.

STEMI

In the diagnosis of ACS, if the ECG shows ST-elevation and cardiac markers are positive, the diagnosis is __________.

STEMI

In ACS, if there is no ST-elevation but cardiac markers are positive, the diagnosis is __________.

NSTEMI

Persistent ST-segment elevation (>20 min) generally reflects an acute total __________ occlusion.

coronary

NSTE-ACS is qualified by symptoms of acute chest pain without persistent __________.

ST-segment elevation

Persistent or transient __________ or T-wave inversion are markers of NSTE-ACS.

ST-segment depression

The process of gradual luminal narrowing by plaque over decades is called __________.

Atherosclerosis

The dynamic process causing rapid complete or partial occlusion of an artery is __________.

Thrombosis

A __________ plaque is characterized by a large lipid core, thin fibrous cap, and high concentration of inflammatory cells.

vulnerable

Acute thrombosis in the heart is often induced by a __________.

plaque rupture

Myocardial infarction of __________ aetiology is classified as Type 1.

atherosclerotic

Cocaine abuse, dissection, and congenital anomalies can cause __________, which are types 2-5.

non-atherosclerotic aetiology

Type 1 MI is related to atherosclerotic plaque rupture leading to resulting __________.

intraluminal thrombus

Type 2 MI involves myocardial injury with necrosis where an imbalance between __________ and demand occurs.

oxygen supply

Conditions like coronary artery spasm or anaemia contribute to __________ MI.

Type 2

ST elevation on an ECG is often associated with a __________ MI on a subsequent Q-wave analysis.

Q-wave

The primary controller of local blood flow is the __________ of the specific tissue.

metabolism

In a healthy heart, increasing preload eventually increases __________, causing a stronger contraction.

afterload

The formula for cardiac index uses body surface area measured in units of __________.

$$m^2$$

According to the lecture, skeletal muscle blood flow at rest is $0.1\,ml/min/g$, while cardiac flow is __________ $ml/min/g$.

$$1$$

Ischemic heart disease can present as __________ pectoris, which is defined as chest pain.

angina

A high density of __________ cells in a plaque usually makes it more stable.

smooth muscle

Type 1 MI involves spontaneous infarction, whereas __________ involves an imbalance without necessarily having plaque rupture.

Type 2 MI

The standard body surface area for a person weighing $70\,kg$ is about __________ $m^2$.

$$1.7$$

__________ receptors and the sympatho-adrenal system participate in cardiovascular adjustments to exercise.

Arterial baroreceptor

In ACS with persistent ST-segment elevation, the cardiac marker __________ is typically elevated.

Troponin

The study of blood flow through the heart and vessels is often referenced to the __________ Textbook of Medical Physiology.

Guyton and Hall

Stroke volume (SV) is controlled by the degree of shortening of the __________ cardiac muscle.

ventricular