Patho//Ch 25, 26, 27//Cardio+Lymph System+Its Alterations

Pulmonary Artery

Vessel that brings deoxygenated blood from the heart’s right ventricles, splits off, to the left and right lungs.

Right Heart

Considered the pulmonary circulation component of the heart

Left Heart

Considered the systemic circulation component of the heart

Pulmonary Vein

Pair of vessels that brings oxygenated blood from the lung to the left atrium.

Aorta

Large vessels bringing oxygenated blood from the left ventricle to the rest of the body.

Vena Cava

Large superior and inferior vessels that brings deoxygenated blood from the upper and lower body (respectively) to the right atrium of the heart.

Tricuspid Valve

The valve between the right atrium and ventricle, which stops back flow.

Mitral (Bicuspid) Valve

The valve between the left atrium and ventricle, which stops back flow.

Pulmonary Semilunar Valve

Three-cusp heart valve between the right ventricle and pulmonary artery.

Aortic Semilunar Valve

Three-cusp heart valve between the left ventricle and the aorta.

Diastole

Stage of heart where there is lower pressure in the ventricle and higher pressure in the atria. Semilunar valves are closed and internal valves are open.

Systole

Stage of heart where there is higher pressure in the ventricle and lower pressure in the atria. Semilunar valves are open and internal valves are closed.

Right Coronary Artery (RCA)

Artery that starts from its own opening just past the aortic semilunar valve, which branches into three vessels: the conus, the right marginal branch, and the posterior descending branch.

Left Coronary Artery (LCA)

Artery that starts from its own opening just past the aortic semilunar valve, and splits into two other arteries: the left anterior descending (LAD) artery (AKA anterior ventricular artery) and the circumflex artery.

Cross-Bridge Theory

That myosin molecules

Heart Wall

A three-layer barrier of the the heart made of predominately smooth muscle.

Cardiac Output

Heart rate multiplied by stroke volume, averaging 5 L/minute for adults.

Ejection Fraction

Stroke Volume/End-Diastolic Volume. Good way to measure how well the heart can push out blood

Preload

The pressure in the ventricles at the end of diastole. There is a greater emphasis on the left ventricle as it is normally stronger.

Frank-Startling Law of the Heart

That the heart's stroke volume (SV) increases in response to a greater filling volume of blood (end-diastolic volume/preload) in the ventricles before contraction.

Afterload

The resistance the flow of blood from the ventricle must overcome to enter the aorta.

Vascular Compliance

The increase in volume that a vessel can accommodate

Resistance

The opposing force to pressure in vessels, which increases when a vessel’s diameter and length is greater.

Factors Influencing Blood Flow

Pressure, resistance, velocity, compliance, and type of flow (laminar vs turbulent)

Varicose Veins

Veins where blood has pooled, making them more winding, protruding, and palpable. Normally caused by trauma or venous distension over time.

Vessel Lumen

The hollow space within a vessel.

Bainbridge Reflex

The changes in heart rate that may occur after intravenous infusions of blood or other fluid.

Varicose Vein Risk Factors

Age, female gender, family history, obesity, pregnancy, DVT, and prior leg injuries.

Chronic Venous Insufficiency

Inadequate venous return over a long period, normally due to varicose veins or valvular incompetence.

Venous Stasis Ulcers

Open sores normally found on the lower legs caused by chronic venous insufficiency.

Thrombus

A blood clot that remains attached to a vessel wall, which are more prevalent in the veins than arteries.

Heart Placement

Diagonally to the left

Pericardial Sac Functions

Displacement protection during movement, barrier from infection and inflammation, influencing blood pressure and heart rate using pain/mechanoreceptors

Pericardial Fluid

Lubricant secreted by the mesothelial layer of the pericardium to enable friction-free interaction between the parietal and visceral pericardia.

Cardiomyocytes

Cells that compose the myocardium, which anchors to the heart’s fibrous skeleton. Over a lifetime, only half of these cells are ever replaced.

Endocardium

The internal lining of the myocardium, composed of connective tissue and squamous cells. Completely continuous with the endothelium of the body’s blood vessels.

Foramen Ovale

An opening between the left and right atrium in fetuses that is normally covered up by the septum primum at the moment of birth.

Chordae Tendinae

Fibers that attach the AV valves to the lower end of the papillary muscles, in order to prevent prolapse or backward movement.

Papillary Muscles

Extensions of the myocardium that work the hold the AV cusps together during ventricular contraction.

Pacemakers

Cells that initiate action potentials in the heart without input from the nervous system, clustered in two nodes.

Sinoatrial Node

Cluster of pacemaker cells located up in the right atrium near the opening of the superior vena cava. It’s the main pacemaker of the heart and also mainly influences both atria. Depolarizes about 60-100 times/minute.

Atrioventricular Node

Cluster of pacemaker cells located in the lower area of the right atrium. Mainly influences both ventricles. Takes action potentials from the other node, but in cases of emergency, will produce 40-60 depolarizations a minute as a replacement.

Bundle of His (Atrioventricular Bundle)

The converged bundle of fibers from the AV node in the posterior interventricular septum, which leads to the right and left bundle branches.

Purkinje Fibers

The terminal branches of the Right and Left Bundle Branches.

Depolarization

The electrical activation of muscle cells, caused by the movement of ions across the cell membrane

Repolarization

The deactivation of muscle cells electrically, followed by a short refractory period.

P Wave

Component of an electrocardiogram that represents atrial depolarization.

PR Interval

Component of an electrocardiogram that represents the time needed for electrical activity to go from the sinus node through the atrium, AV node, to the Purkinje fibers to activate the ventricles.

QRS Complex

Component of an electrocardiogram that represents ventricle depolarization (and atrial repolarization).

ST Interval

Component of an electrocardiogram that represents when all ventricle myocardium is depolarized.

T Wave

Component of an electrocardiogram that represents ventricle repolarization.

Automaticity

The property of generating spontaneous depolarization to threshold.

Rhythmicity

The regular generation of an action potential by the heart’s conduction system.

Sympathetic Stimulation

What general increases the electrical conductivity and the strength of myocardial contraction

Vagal Parasympathetic Stimulation

What generally slows the conduction of action potentials and reducing the strength of myocardial contraction

Stroke Volume

The volume of blood ejected from the heart during systole (averaging at 70mL)

Laplace Law

That wall tension generated in the wall of the ventricle (or any vessel) to produce a given intraventricular pressure depends directly on the size of the ventricle (its radius) and inversely on ventricular wall thickness.

Cardiovascular Vasomotor Control Center

Area in the medulla and pons areas of the brain stem, with other areas in the hypothalamus (regulates cardio response related to temperature), cerebral cortex (regulates cardio response related to emotions), and thalamus.

Baroreceptors

Components found in the aortic arch and the carotid arteries, which reflexively gives an output that influences blood pressure in the short term.

Components of Blood Pressure

Smooth muscle resistance in arteries, myocardial contractility, and heart rate.

Peripheral Vascular System

Part of the systemic circulation that supplies the skin and the extremities, with an emphasis on the legs and feet.

Vasa Vasorum

Vessels in only in larger vessel walls, located in their tunica extrema.

Elastic Arteries

Arteries that have a thick tunica media that are less muscular. They are found closer to the heart and includes the aorta.

Muscular Arteries

Medium and small arteries that have less elastic fibers. They are further from the heart since they need to contract to flow through the body. They can vasoconstrict and vasodilate to impact the lumen.

Arteriole

The vessel brings blood away from the heart where the diameter of the lumen is less than 0.5 mm. They are predominantly made of smooth muscle.

Vascular Endothelium

The lining of the blood vessels that is sometimes considered its own endocrine organ, since it partakes in blood-based immune and inflammation response, angiogenesis, and filtration.

Mean Arterial Pressure (MAP)

The average pressure in the arteries through the cardiac cycle. This averages from 70-110 mmHg

MAP Formula

P_d [diastolic pressure] + 1/3(P_s [systolic pressure] — P_d)

Vasodialating Horomones/Compounds

Natriuretic peptides, nitric oxide, adrenomedullin, endothelins, and prostacyclin

Vasoconstricting Horomones/Compounds

Epinephrine, norepinephrine, angiotensin II, and vasopressin

Epinephrine

Catecholamine

Norepinephrine

Catecholamine that works primarily as a neurotransmitter; but when released from the adrenal medulla, it works as one of the strongest vasoconstrictors.

Vasopressin & Aldosterone

Mild vasoconstrictors that primarily work to cause the reabsorption of water in the kidneys.

Natriuretic Peptides (NPs)

Family of hormones that work as both vasodialators and regulators of sodium and water excretion.

Nitric Oxide

Molecule produced by endothelial cells used for intracellular and intercellular signalling, which works as a vasodilator and an inhibitor of smooth muscle proliferation.

Adrenomedullin (ADM)

Peptide with powerful vasodilatory activity found in many tissues. It has clear functions in fetal dev

Coronary Perfusion Pressure

The difference between pressure in the aorta versus the coronary vessels.

Major Lymph Organs

Tonsils, bone marrow, spleen, and the thymus gland.

Thoracic Duct

Major lymphatic duct that receives lymph from lymph venules and veins around the entire body other than the right arm, right head and thorax.

Varicose Vein

Veins where there’s pooled blood, causing distended, palpable vessels, caused by either injury or disease that damages the valves or gradual distention from gravity.

Risk Factors of Varicose Veins

Older age, being female, family history, obesity, pregnancy, DVT, and previous leg injuries.

Chronic Venous Insufficiency

Inadequate venous return over a long period of time. Often a progression from varicose veins, especially in obese people. It can cause skin ulcers.

Thromboembolus

A thrombus that has detached from the vessel wall.

Deep Vein Thrombosis (DVT)

Serious condition where a blood clot forms in a deep vein, usually in the legs, causing symptoms like swelling, pain, warmth, and redness

Triad of Virchow

The factors promoting venous thrombosis: venous stasis (immobility, age, heart failure), venous endothelial damage (injury, surgery, needles), hypercoagulable states (pregnancy, taking HRT or birth control, maligancies)

V Leiden Mutation

Most common inherited abnormality that causes a higher risk of clots and DVT, affecting 3-8% of the population.

Superior Vena Cava Syndrome

Considered an oncologic emergency; a progressive occlusion of the superior vena cava that leads to vessel distention in the head and upper extremities.

Causes of SVCS

Bronchogenic cancer, lymphomas, cancer metastasis, tuberculosis, mediastinal fibrosis, cystic fibrosis, invasive procedures such as pacemaker wires or blood vessel catheters.

Primary Hypertension

Essential/idiopathic high blood pressure caused by genetic and environmental factors.

Risk Factors of Primary Hypertension

Family history, diet of high sodium, or low potassium, calcium, or magnesium, tobacco or alcohol consumption, or obesity.

Secondary Hypertension

High blood pressure tied to an underlying disease process or medication.

Renin-Angiotensin-Aldosterone System (RAAS)

Hormone system that regulates long-term blood pressure, blood volume, and sodium balance

Secondary Hypertension Causes

Renal vascular or parenchymal disease, adrenocortical tumors, pheochromocytoma, oral contraceptives, corticosteroids, or antihistamines.

Hypertensive Crisis

Rapidly progressing hypertension where systolic pressure is >180 mmHg OR diastolic pressure is >120 mmHg.

Causes of Hypertensive Crisis

Complications in pregnancy, cocaine/amphetamine use, adrenal tumors, and alcohol withdrawal.

Orthostatic (postural) Hypotension (OH)

A decrease in systolic blood pressure of at least 20 mmHg or at least 10 mmHg for diastolic blood pressure within three minutes of standing up. It affects men more than women, normally for ages 40-70, and increases risks of falls.

Acute OH

Hypotension when standing is more common in the elderly when the normal regulatory mechanisms are inadequate, including as a drug side effect, extended immobility, starvation, etc.

Chronic OH

Hypotension when standing that is idiopathic or secondary to a different disease like endocrine disorders like diabetes, metabolic disorders like porphyria, or nervous system disorders like Parkinson’s.

Aneurysm

Localized dialation or outpouching of a vessel wall or cardiac chamber.

Embolism Examples

Dislodged thrombus, air bubbles, amniotic fluid, aggregate of fat, bacteria, cancer cells, or foreign substances.