Cardiovascular System and Hypertension Flashcards

Flashcards about the cardiovascular system, vascular diseases, disorders, and hypertension.

Cardiovascular System

A closed system of the heart and blood vessels that delivers oxygen and nutrients and removes carbon dioxide and other waste products.

Incompetent Valve

Backflow and repumping of blood due to a faulty valve.

Stenosis (Heart Valve)

A stiff heart valve that increases the heart's workload.

Heart Sound

Lup (bicuspid and mitral valve or AV valves close), Dub (aortic and pulmonary or semilunar valves close)

Coronary Circulation

The heart has its own nourishing circulatory system, including coronary arteries and cardiac veins.

Dangerous Plaque

associated with inflammation, causing more occlusion and can rupture altering blood flow, leading to the development of clots (thrombi)

Hypertension

Pressure in the blood vessels is elevated at 140/90 mmHg or higher.

Systolic Pressure

Pressure in blood vessels when the heart contracts or beats.

Diastolic Pressure

Pressure in the vessels when the heart rests between beats

Possible Causes of Primary Hypertension

Overactivity of the sympathetic nervous system, renin-angiotensin-aldosterone system, kidney retention of sodium and water, hormonal inhibition of sodium-potassium transport, interactions involving insulin resistance and endothelial function.

Complications of Hypertension

Left ventricular hypertrophy, myocardial ischemia, myocardial infarction (heart attack), nephrosclerosis (kidney failure), transient ischemic attack (mini stroke), cerebral thrombosis, aneurysm, hemorrhage, retinal vascular sclerosis.

Orthostatic Hypotension

Drop in blood pressure that occurs on standing.

Aneurysm

Localized dilation of a vessel wall, particularly susceptible in the aorta.

Thrombus

Clot that remains attached to a vascular wall.

Embolus

Mobile aggregate of substances that occludes the vasculature.

Sources of Emboli

Clots, air, amniotic fluid, fat.

Vasospastic Disorders

Raynaud disease, Prinzmetal angina, Buerger disease

Raynaud Disease

Involving arterioles of the extremities, aggravated in cold weather

Prinzmetal Angina

Coronary arteries vasoconstrict & vasospasm, decreases the blood flow, occurs at rest.

Buerger Disease

Immune and inflammatory disease of the peripheral arteries of the hands and feet, associated with smoking.

Varicosities

Areas of veins in which blood has pooled, usually in the saphenous veins, caused by damaged valves or chronic venous distention.

Superior Vena Cava Syndrome

Progressive occlusion of the superior vena cava that leads to venous distention in the upper extremities and head, usually caused by bronchogenic cancer.

Coronary Artery Disease (CAD)

Almost always the result of atherosclerosis that narrows or occludes the coronary arteries.

Angina Pectoris

Chest pain; prolonged, unrelieved ischemia that interrupts blood supply to the myocardium.

Pericarditis

Inflammation of the heart sac.

Pericardial Effusion

The accumulation of fluid in the pericardial cavity; excessive cardiac compression causes tamponade, leading to decreased cardiac output and shock.

Constrictive Pericarditis

Fibrotic lesions encase the heart in a rigid shell, compressing the heart and reducing cardiac output.

Cardiomyopathies

Disorders are usually the result of remodeling caused by the myocardial and neurohumoral responses to ischemic heart disease and hypertension; may also be due to exposure to infectious disease and toxins.

Categorized Cardiomyopathies

Dilated (congestive), restrictive (rigid and noncompliant), and hypertrophic (asymmetric).

Valvular Dysfunction

Congenital/acquired valvular stenosis and regurgitation

Valvular Stenosis

Valve is narrowed and constricted.

Valvular Regurgitation

Cusps fail to shut completely, allowing blood to leak back.

Aortic Stenosis

Aortic valves do not open completely; results in ventricular hypertrophy, caused by inflammatory damage (Rheumatic fever), Congenital malformation, Degeneration caused by calcification

Rheumatic Fever and Rheumatic Heart Disease

An inflammatory disease that results from a delayed immune response to a streptococcal infection.

Infective Endocarditis

general term for inflammation of the heart’s inner layer, especially the cardiac valves, most common cause is Staphylococcus aureus, followed by Viridans streptococcus

Mitral Stenosis

Impairs flow from left atrium to left ventricle (results in atrial enlargement).

Regurgitation

Aortic, mitral, tricuspid.

Mitral Valve Prolapse

The two valve flaps of the mitral valve do not close smoothly or evenly but bulge (prolapse) upward into the left atrium causing regurgitation.

Shock

Widespread impairment of cellular metabolism involving positive feedback loops leading to multiple organ dysfunction syndrome.

Cardiogenic Shock

Decreased cardiac output, tissue hypoxia, and the presence of adequate intravascular volume.

Hypovolemic Shock

Caused by loss of blood or fluid in large amounts; tissue perfusion ultimately decreases and results in impaired cellular metabolism.

Anaphylactic shock

Caused by physiologic recognition of a foreign substance; inflammatory response is triggered, and a massive vasodilation with fluid shift into the interstitium follows.

Multiple Organ Dysfunction Syndrome (MODS)

Progressive failure of two or more organ systems after a severe illness or injury, triggered by chronic inflammation, necrotic tissue, severe trauma, burns, adult respiratory distress syndrome, acute pancreatitis, and other severe injuries.

Clinical Manifestations of MODS

Includes inflammation, tissue hypoxia, and hypermetabolism; lung is usually the first organ to fail.

Heart: Conduction System

Intrinsic conduction system (nodal system); heart muscle cells contract, without nerve impulses, in a regular, continuous way.

Sinoatrial Node

Pacemaker (located in wall of right atria); Initiates depolarization wave.

Depolarization

The process where cardiac cells become more positively charged, initiating muscle contraction & blood pumping resulting from the flow of ions (sodium & potassium) across the cell’s membrane. It provides stimulus to contract.

Repolarization

The return of the cell membrane to its resting potential, due to the flow of ions across the cell membrane. A cell must do this before it can respond to a stimulus.

Excitability

The ability of cardiac cells to reach a threshold and respond to a stimulus.

Pathology of the Heart

Damage to AV node = release of ventricles from control = slower heart beat,can lead to fibrillation = lack of blood flow to the heart, Tachycardia = more than 100 beats/min, Bradycardia = less than 60 beats/min

Cardiac Output (CO)

Amount of blood pumped by each side of the heart in one minute

Stroke Volume (SV)

Volume of blood pumped by each ventricle in one contraction, SV = end-diastolic volume x end-systolic volume

Starling’s Law of the Heart

The more that the cardiac muscle is stretched, the stronger the contraction.

Regulation of Heart Rate

Increased heart rate: Sympathetic nervous system (Crisis and Low blood pressure), Hormones (Epinephrine and Thyroxine), Exercise, decreased blood volume, Decreased heart rate: Parasympathetic nervous system, High blood pressure or blood volume, Decreased venous return

Hypertension

Also known as high blood pressure, is when the pressure of the blood being pumped through your arteries is higher than it should be.

Hypertension Measure

A systolic blood pressure ( SBP) >139 mmHg and/or A diastolic (DBP) >89 mmHg. Based on the average of two or more properly measured, seated BP readings. On each of two or more office visits.

Primary Hypertension

Idiopathic (unknown) cause; pressure is just high. Most common

Secondary Hypertension

Caused by an underlying condition such as chronic kidney disease, sleep apnea, alcohol addiction, thyroid dysfunction and others. Less common

Malignant Hypertension

A rapid rise in blood pressure AND organ damage due to increased blood pressure. Generally, malignant hypertension is >240/120.

Pulmonary Hypertension

A type of high blood pressure that affects the arteries in your lungs and the right side of your heart.

White Coat Hypertension

Means that your blood pressure is higher when taken in a medical setting than when taken at home.

Genetics

Having family members with hypertension increases the likelihood that you will too.

Race

High blood pressure is more common in people with dark skin than in people with pale skin.

Age

Your blood vessels become more rigid as you age, preventing them from opening as effectively as when you were younger, which increases peripheral resistance.

Effects of Hypertension

Arteriosclerosis, Heart Failure, Heart Attack, Stroke, Chronic Renal Failure.

Ischemic Stroke

A stroke occurs when a blood clot blocks an artery (a blood vessel that carries blood from the heart to the body) or a blood vessel (a tube through which the blood moves through the body) breaks, interrupting blood flow to an area of the brain. When either of these things happen, brain cells begin to die and brain damage occurs.

Hemorrhagic Stroke

happens when a blood vessel in the brain bursts and spills blood into or around the brain.

Transient Ischemic Attack (TIA)

An event, sometimes called a mini-stroke, with stroke symptoms that last less than 24 hours before disappearing. Generally no permanent brain damage occurs, but TIAs are a serious warning sign of stroke and should not be ignored.

Signs/Symptoms of Stroke

Sudden numbness or weakness of face, arm, or leg, sudden confusion, trouble speaking or understanding, Sudden trouble seeing in one or both eyes,Sudden trouble walking, dizziness, loss of balance or coordination, Sudden severe headache with no known cause

Treatment of Stroke

Medications: Clot busting drugs, Blood pressure medications

Gender

Women have more strokes than men.

Race

High blood pressure is more common in people with dark skin than in people with pale skin.

Normal Blood Flow

Pulmonary circuit: Unoxygenated blood flows from the right side of the heart to the lungs and back to the left side of the heart, Systemic circuit: Oxygenated blood flows from the left side of the heart to the body (upper & lower) and back to the right side of the heart

Cardiac Cycle

Performance of the heart over one full heartbeat, Diastole: chamber relaxation & stretching, Chamber fills with blood, Systole: chamber contraction, Chamber pumps blood out

Hypertension: Pathophysiology

Multifactorial and complex: Increased cardiac output and peripheral vascular resistance

Renin-Angiotensin System Modulators

Angiotensin converting enzyme inhibitors, Angiotensin receptor blockers, Direct renin antagonist, Aldosterone receptor antagonist

Andrenergic Blocker Aplha (Non-selective) Blocker

Given orally once daily (exception is prazocin [bid-tid] - see appendix for dose comparisons by drug- Start low and double dose every week to desired target dose: Dose adjust in hepatic impairment (prazosin and terazosin)

ACYANOTIC DEFECTS

Left-Right shunt lesions: Septal Defects, Patent Ductus Arteriosus, Obstructive lesions

CYANOTIC DEFECTS

Cardiac insufficiency: Truncus arteriosus, Hypoplastic left heart syndrome