Cardiovascular System Quiz

Disorders of the Cardiovascular System

• This topic covers various cardiovascular disorders, including anatomy, circulatory system, and cardiac disorders.

Outline

• Anatomy: Chambers, Valves, Layers, Circulatory system, Arterial system, Hemodynamic Function, Conduction of the heart
• Cardiac disorders: Coronary atherosclerosis, Hypertension, Orthostatic hypertension, Acute coronary syndromes, Angina pectoris, Myocardial infarction, Cardiac tamponade, Heart failure

Objectives

• Students will be able to describe 2-3 anatomical parts of the cardiovascular system.
• Students will be able to explain the circulatory system.
• Students will be able to define 3 cardiac disorders.
• Students will be able to compare and contrast angina pectoris and myocardial infarction.
• Students will be able to classify the types of hypertension based on categories.
• Students will be able to identify heart failure types and clinical manifestations.
• Students will be able to classify aneurysm and common clinical manifestations.

Cardiovascular System

• Heart has four chambers:

  • Right Atrium: Receives venous blood from the entire body via superior and inferior vena cava.
  • Right Ventricle: Receives blood from right atrium and pumps it to the lungs via the pulmonary artery.
  • Left Atrium: Receives oxygenated blood from the lungs via pulmonary veins.
  • Left Ventricle: Receives blood from the left atrium and pumps it to the entire body via the aorta.

• Heart has four valves:

  • Mitral valve
  • Aortic valve
  • Tricuspid valve
  • Pulmonic valve

Cardiovascular System Functions

• Main function is transport. Delivers oxygen and nutrients to tissues. Carries waste products from cellular metabolism to excretory organs.
• Circulates electrolytes and hormones. Transports various immune substances that contribute to the body's defense mechanisms.
• Helps regulate temperature (homeostasis).

Cardiac Cycle

• Used to describe the rhythmic pumping action of the heart.
• Divided into two parts:
  • Systole: the period during which the ventricles are contracting.
  • Diastole: the period during which the ventricles are relaxed and filling with blood.

Heart Layers

• Outer Epicardium (outer layer)

• Middle Myocardium (middle layer)

• Inner Endocardium (inner layer)

• The Pericardium has two layers (serous and fibrous), encloses the pericardial cavity, containing pericardial fluid. Fixes the heart to the mediastinum and protects it and provides lubrication.

Cardiac Output

• Amount of blood the heart pumps each minute.
• Determined by CO = SV x HR.
• Stroke volume: amount of blood pumped with each beat.
• Heart rate: number of times the heart beats each minute.
• Resting adult CO: approximately 5.25 L/min.
• Regulation of stroke volume is by three factors: Preload, Contractility, Afterload.

Peripheral Resistance and Regulation of Blood Flow

• Blood pressure = cardiac output × peripheral vascular resistance

• Regulation:

  • Autonomic nervous system (ANS)
  • Kidneys (renin-angiotensin-aldosterone)
  • Endocrine system (catecholamines, kinins, serotonin, histamine)
  • Vasomotor center (sympathetic)
  • Cardioinhibitory center (parasympathetic)

• Factors affecting hemodynamic function: Volume, Pressure, Resistance

Hypertension

• Systolic pressure: pressure at the highest point of the pressure pulse.
• Diastolic pressure: lowest pressure in the arteries.
• Pulse pressure: difference between systolic and diastolic pressure
• Mean arterial pressure: average pressure during ventricular contraction and relaxation.
• Normal blood pressure: typically around 120/80 mm Hg
• Hypertension defined based on different categorizations of both systolic and diastolic pressure (elevated, stage 1, stage 2, and crisis).
• Categories of hypertension: Primary/essential, Secondary, Malignant

Risk factors, clinical manifestation, and causes of hypertension

Different lifestyle factors, genetic, and other risk factors contribute to hypertension (e.g., high salt intake, obesity, excess alcohol, lack of physical activity).

• Clinical manifestations of hypertension are frequently related to organ damage (e.g., visual changes, kidney issues).

Orthostatic Hypotension

• Abnormal decrease in blood pressure when moving to an upright position.
• Causes: Decrease in venous return, inadequate circulatory response, conditions impairing muscle pump function, and conditions interfering with cardiovascular reflexes.

Acute Coronary Syndromes (ACS)

• Group of clinical disorders.

• Includes acute myocardial infarction (MI), ST-segment elevation MI (STEMI), non-ST-segment elevation MI (NSTEMI), and unstable angina.

• Causes of ACS: Aging, drug use, elevated serum triglycerides and cholesterol levels, excessive fat intake, gender (men), hypertension, obesity, positive family history, sedentary lifestyle, smoking, and stress.

Angina Pectoris

• Syndrome characterized by pain or pressure in the anterior chest due to insufficient coronary blood flow.
• Increases in myocardial oxygen demand (physical exertion or stress) and insufficient blood flow to meet demand leads to angina.
• Types: Stable angina, Unstable angina, Intractable/refractory angina, Variant angina.

Myocardial Infarction (MI)

• Ischemia occurs first due to imbalance between blood flow and oxygen demand.
• Ischemia can be resolved by improving blood flow or reducing oxygen needs if reversed.
• Injury: occurs when ischemia lasts long enough to cause area damage
• Infarction: the final stage of myocardial cell death.

Clinical Findings (MI)

• Persistent crushing chest pain radiating to left arm, jaw, neck, or shoulder blades.
• Cool extremities, perspiration, anxiety, restlessness due to catecholamine release.
• Fatigue and weakness due to reduced perfusion to skeletal muscles.

Test Results (MI)

• Serial 12-lead ECG.
• Cardiac enzymes and proteins (CK-MB, troponin T and I, and myoglobin).
• Laboratory tests.
• Echocardiography, Chest X-rays, Cardiac catheterization.

Cardiac Tamponade

• Pericardial compression of the heart
• Causes: Acute myocardial infarction, chronic renal failure, connective tissue disorders, effusion (cancer, infections), trauma, or anticoagulant therapy.
• Symptoms: Dyspnea, fatigue, agitation, restlessness, syncope, shock, anuria, increased jugular venous pressure, tachycardia, hypotension.

Heart Failure

• Syndrome, not a disease.
• Occurs when the heart cannot pump enough blood to meet the body's metabolic needs.
• Results in intravascular and interstitial volume overload and poor tissue perfusion.
• Can be systolic (contraction problem) or diastolic (filling problem) failure.
• Heart failure causes: Abnormal heart muscle function (eg., MI), increased left ventricular volume (eg., valve disease, large IV fluid volumes), and increased left ventricular pressure (eg., hypertension, COPD).

Aortic Aneurysms

• Localized dilatation and weakening of the arterial wall.
• Common locations: abdominal or thoracic aorta.
• Types: Saccular (bulging on one side), Fusiform (circumferential dilatation), Dissecting (tear in the intima allowing blood flow between layers).
• Etiology: atherosclerosis, trauma (car accidents), syphilis, congenital defects, hypertension.
• Signs and symptoms: usually asymptomatic until large or rupture, severe pain, shock, blood flow obstruction, loss of pulses, and organ dysfunction.

Test your knowledge on the key components and functions of the cardiovascular system. This quiz covers essential topics including heart anatomy, valve functions, and blood pressure regulation. Perfect for students studying human biology or health sciences.