Cardiovascular Function and Pathophysiology Practice Flashcards

A comprehensive vocabulary review set of 250 flashcards covering cardiovascular anatomy, cardiac cycle physiology, electrical conduction, valvular defects, cardiomyopathies, heart failure, dysrhythmias, vascular pathology, and blood pressure regulation based on nursing pathophysiology lecture sources.

Pulmonary Circulation

The portion of the cardiovascular system that carries deoxygenated blood away from the heart to the lungs for gas exchange and returns oxygenated blood back to the heart.

Systemic Circulation

The circuit that carries oxygenated blood through the body to supply nutrients, remove cellular waste, and transport hormones, working in conjunction with the lymphatic system.

Pericardium

The double-walled sac that surrounds and protects the heart, providing structural support and reducing friction during cardiac contractions.

Myocardium

The thick middle muscular layer of the heart wall responsible for pumping blood through the circulatory system.

Endocardium

The smooth inner epithelial lining of the heart chambers and cardiac valves.

Atria

The two upper receiving chambers of the heart that collect blood returning to the heart from the systemic or pulmonary circulation.

Ventricles

The two lower muscular pumping chambers of the heart that eject blood into the pulmonary trunk or systemic aorta.

Superior Vena Cava

The large vein that returns deoxygenated systemic blood from the head, neck, upper limbs, and chest to the right atrium.

Inferior Vena Cava

The large vein that returns deoxygenated systemic blood from the lower limbs, abdomen, and pelvis to the right atrium.

Tricuspid Valve

The atrioventricular valve located between the right atrium and right ventricle that prevents the backflow of blood during ventricular systole.

Pulmonic Valve

The semilunar valve located between the right ventricle and the pulmonary trunk that prevents regurgitation of blood into the right ventricle.

Pulmonary Arteries

The blood vessels that carry deoxygenated blood away from the right ventricle into the lungs for oxygenation.

Pulmonary Veins

The blood vessels that transport freshly oxygenated blood from the lungs into the left atrium of the heart.

Mitral Valve

The bicuspid atrioventricular valve situated between the left atrium and left ventricle that prevents blood backflow during left ventricular contraction.

Aortic Valve

The semilunar valve located between the left ventricle and the aorta that prevents backflow of oxygenated blood into the left ventricle.

Aorta

The main arterial trunk that receives oxygenated blood directly from the left ventricle and distributes it to the systemic circulation.

Interventricular Septum

The muscular wall separating the left and right ventricles of the heart.

Cardiac Cycle

The sequence of events in a single heartbeat, encompassing continuous phases of atrial and ventricular contraction (systole) and relaxation (diastole).

Systole

The active work phase of the cardiac cycle during which the heart muscles contract and pump blood out of the chambers into the arteries.

Diastole

The cardiac resting and filling phase during which the heart muscle relaxes and the chambers fill with blood.

Pulse Pressure

The mathematical difference between systolic and diastolic blood pressure (normally around $40\,m\text{m }Hg$), reflecting overall contractile force.

Cardiac Output (CO)

The total volume of blood pumped by the heart per minute, calculated as stroke volume multiplied by heart rate ($CO = SV \times HR$).

Stroke Volume (SV)

The volume of blood ejected from the left ventricle with each individual cardiac contraction.

Ejection Fraction (EF)

The percentage of blood pumped out of the left ventricle with each contraction, with normal resting values ranging between $50\%$ and $70\%$.

Peripheral Vascular Resistance (PVR)

The force opposing the flow of blood within the peripheral blood vessels, which increases as vessel diameter decreases.

Preload

The volume of blood remaining in the ventricles at the end of diastole, representing end-diastolic pressure and total venous return.

Afterload

The resistance or pressure that the left ventricle must overcome to eject blood into the systemic circulation.

Chronotropic Effect

An effect or influence that alters the rate or frequency of heart contractions.

Dromotropic Effect

An effect or influence that alters the speed of electrical conduction through the heart's conductive tissue.

Inotropic Effect

An effect or influence that alters the force or strength of muscular contraction in the heart.

Chemoreceptors

Specialized sensory receptors located in the brain, heart, blood vessels, and kidneys that detect chemical changes such as oxygen, carbon dioxide, and pH in the blood.

Baroreceptors

Pressure-sensitive sensory receptors located in the carotid arteries and aorta that monitor arterial wall stretch and regulate blood pressure.

Antidiuretic Hormone (ADH)

A hormone produced by the hypothalamus and released by the posterior pituitary that increases renal water reabsorption, resulting in increased blood volume and elevated blood pressure.

Aldosterone

A mineralocorticoid hormone secreted by the adrenal cortex that promotes renal reabsorption of sodium ($Na^+$) and water retention, expanding blood volume.

Renin-Angiotensin-Aldosterone System (RAAS)

A major neurohumoral regulatory pathway activated by decreased renal perfusion that triggers vasoconstriction and fluid retention to restore blood pressure.

Renin

An enzyme secreted by the kidneys in response to low blood pressure or reduced renal blood flow that converts angiotensinogen into angiotensin I.

Angiotensinogen

A plasma protein precursor produced continuously by the liver that is cleaved by renin to form angiotensin I.

Angiotensin I

An inactive peptide produced by the cleavage of angiotensinogen that is converted to active angiotensin II by angiotensin-converting enzyme.

Angiotensin-Converting Enzyme (ACE)

An enzyme primarily located in pulmonary capillary vascular beds that converts angiotensin I into the potent vasoconstrictor angiotensin II.

Angiotensin II

A powerful vasoconstrictor peptide that raises blood pressure directly by narrowing arteries and indirectly by stimulating aldosterone release.

Tunica Intima

The innermost, smooth epithelial layer of a blood vessel wall that reduces fluid friction against circulating blood.

Tunica Media

The middle muscular layer of a blood vessel composed of smooth muscle and elastic tissue that regulates vessel diameter.

Tunica Adventitia

The outer connective and elastic tissue layer of a blood vessel that anchors the vessel to surrounding anatomical structures.

Arteries

Thick-walled, elastic blood vessels that carry oxygenated blood away from the heart to body tissues under high pressure.

Arterioles

Small arterial branches that control vascular resistance and regulate blood flow into capillary beds.

Capillaries

Microscopic, single-celled blood vessels where nutrient, gas, and metabolic waste exchange takes place between blood and tissue fluids.

Veins

Low-pressure, thin-walled blood vessels containing valves that return deoxygenated blood back toward the heart.

Venules

Small venous vessels that collect deoxygenated blood from capillaries and empty into larger systemic veins.

Left Coronary Artery

A major coronary artery arising from the aorta that splits into the circumflex and anterior interventricular arteries to supply the left myocardium.

Right Coronary Artery

A major vessel originating from the aorta that branches into the marginal and posterior interventricular arteries to supply the right atrium and ventricle.

Circumflex Artery

A branch of the left coronary artery that curves around the heart to supply oxygenated blood to the left atrium and lateral wall of the left ventricle.

Anterior Interventricular Artery

A branch of the left coronary artery (also known as the left anterior descending) that supplies the anterior wall of both ventricles and the interventricular septum.

Coronary Sinus

A wide venous channel on the posterior aspect of the heart that collects deoxygenated venous blood from cardiac veins and empties directly into the right atrium.

Chylomicrons

Large lipoprotein particles absorbed into the blood and lymph that transport dietary cholesterol and triglycerides from the intestines to peripheral tissues.

Very-Low-Density Lipoproteins (VLDL)

Triglyceride-rich lipoproteins synthesized by the liver that carry endogenously produced lipids to peripheral fat and muscle tissues.

Low-Density Lipoproteins (LDL)

Lipoproteins referred to as 'bad' cholesterol that transport cholesterol to peripheral tissue cells and contribute to atheromatous vascular plaque formation.

High-Density Lipoproteins (HDL)

Lipoproteins referred to as 'good' cholesterol that transport excess cholesterol away from peripheral tissues back to the liver for clearance.

Conductivity

The intrinsic ability of specialized cardiac tissue cells to transmit electrical impulses throughout the myocardium.

Excitability

The capability of cardiac muscle cells to respond to electrical stimuli and initiate an action potential.

Automaticity

The unique property of specialized cardiac pacemaker cells to generate spontaneous electrical impulses without external nerve stimulation.

Sinoatrial (SA) Node

The primary intrinsic pacemaker of the heart located high in the right atrium that generates impulses at an intrinsic rate of $60\text{--}100\,\text{bpm}$.

Atrioventricular (AV) Node

A secondary cardiac pacemaker located near the interatrial septum that delays electrical conduction to allow ventricular filling and fires at $40\text{--}60\,\text{bpm}$ if the SA node fails.

Bundle of His

A collection of specialized cardiac muscle fibers that conducts electrical impulses from the AV node down through the interventricular septum.

Purkinje Network

Specialized conductive fibers distributed throughout the ventricular myocardium that trigger synchronized ventricular contraction, capable of generating escape rhythms at $20\text{--}40\,\text{bpm}$.

Depolarization

The rapid influx of positive sodium or calcium ions across cardiac cell membranes that increases electrical charge and triggers muscle contraction.

Repolarization

The cellular recovery process during which ions return across the cardiac membrane to restore the resting membrane potential.

Electrocardiogram (ECG / EKG)

A graphic recording of the electrical activity generated by the heart during depolarization and repolarization cycles.

P Wave

The initial deflection wave on an ECG that represents electrical depolarization of the atria.

QRS Complex

The series of ECG waves representing rapid ventricular depolarization, normally lasting $0.04\text{--}0.12\,\text{seconds}$.

T Wave

The ECG deflection wave following the QRS complex that represents electrical repolarization of the ventricles.

PR Interval

The ECG duration from the start of the P wave to the beginning of the QRS complex (normally $0.12\text{--}0.20\,\text{seconds}$), measuring conduction time from atria through the AV node.

ST Segment

The early ventricular repolarization period on an ECG between the QRS complex and T wave, normally flat along the electrical baseline.

QT Interval

The total duration on an ECG from the start of ventricular depolarization to the end of ventricular repolarization.

Phase 0 (Action Potential)

The rapid depolarization phase of the cardiac action potential driven by a massive influx of sodium ions ($I_{Na}$).

Phase 1 (Action Potential)

The brief rapid repolarization phase resulting from the closure of fast sodium channels and efflux of potassium ions ($I_{to}$).

Phase 2 (Action Potential)

The plateau phase of the cardiac action potential maintained by a slow inward calcium current ($I_{Ca}$) balancing potassium efflux.

Phase 3 (Action Potential)

The final rapid repolarization phase where calcium channels close and potassium efflux ($I_{Ks}, I_{Kr}$) restores negative membrane potential.

Phase 4 (Action Potential)

The resting membrane potential phase maintained by the sodium-potassium ATPase pump and resting potassium current ($I_{K1}$).

Sinus Rhythm

The normal cardiac rhythm established by impulses originating regularly from the sinoatrial node.

Congenital Heart Defects

Structural anomalies of the heart or great vessels present at birth, representing the most common type of birth defect.

Atrial Septal Defect (ASD)

An acyanotic congenital heart defect characterized by an abnormal opening in the interatrial septum, allowing left-to-right blood shunting.

Ventricular Septal Defect (VSD)

An acyanotic congenital opening in the interventricular septum that causes oxygenated blood to shunt from the high-pressure left ventricle to the right ventricle.

Patent Ductus Arteriosus (PDA)

An acyanotic congenital condition in which the fetal vascular connection between the aorta and pulmonary artery fails to close after birth.

Coarctation of the Aorta

A congenital structural narrowing of the aorta that obstructs systemic blood flow and increases left ventricular afterload.

Tetralogy of Fallot

A complex cyanotic congenital heart defect comprising four key abnormalities: pulmonary valve stenosis, ventricular septal defect, overriding aorta, and right ventricular hypertrophy.

Acyanotic Defect

A classification of congenital heart defects that do not typically produce systemic cyanosis, characterized by left-to-right blood shunting or obstructive lesions.

Cyanotic Defect

A classification of congenital heart defects causing unoxygenated blood to enter the systemic circulation via right-to-left shunting, resulting in persistent cyanosis.

Pericarditis

Inflammation of the pericardium caused by viral infection, trauma, myocardial infarction, tuberculosis, malignancy, or autoimmune conditions.

Pericardial Effusion

An abnormal accumulation of fluid within the pericardial cavity between the parietal and visceral pericardial layers.

Cardiac Tamponade

A life-threatening medical emergency caused by rapid fluid accumulation in the pericardial sac that compresses the heart and severely restricts cardiac filling.

Cardiac Tamponade Manifestations

The clinical sign pattern of cardiac tamponade, including falling arterial pressures, rising venous pressures, narrowing pulse pressure, and muffled heart sounds.

Constrictive Pericarditis

A chronic form of pericarditis where fibrous thickening and scarring cause a loss of pericardial elasticity, restricting cardiac diastolic expansion.

Pericardial Friction Rub

A grating, high-pitched extra cardiac sound produced by inflamed pericardial surfaces rubbing against one another.

FRICTION Mnemonic

A clinical memory aid for pericarditis signs: Friction rub, Relieved sitting up, Increased on inspiration, Chest pain (sharp), Tachycardia, Increased lying flat, Overall malaise/fever, Not relieved by medication.

Infective Endocarditis

An infection of the endocardium and heart valves, commonly caused by Streptococcus or Staphylococcus bacterial colonization.

Vegetation (Endocarditis)

Fibrin, platelet, and bacterial thrombi clusters that form on cardiac valves in infective endocarditis, capable of embolizing to distant organs.

Osler's Nodes

Painful, tender erythematous nodular lesions located on the pads of the fingers and toes associated with infective endocarditis.

Janeway Lesions

Non-tender, flat, red or purpuric macules located on the palms and soles caused by septic microemboli in infective endocarditis.

Roth Spots

Retinal hemorrhages with pale central spots seen during ophthalmoscopic examination in patients with infective endocarditis.

Splinter Hemorrhages

Tiny, linear longitudinal red-to-black hemorrhages running underneath the nail beds caused by microembolization in endocarditis.