Cardiovascular System Notes

Blood Pressure

  • Blood pressure is the force of blood exerted on the inner walls of blood vessels.

  • It is highest in the arteries and lowest in the veins.

  • Systolic pressure: Ventricles contract (typically around 120 mmHg).

  • Diastolic pressure: Ventricles relax (typically around 80 mmHg).

  • Normal blood pressure range: 120/80 mmHg.

  • Factors like cardiac output and blood viscosity can affect blood pressure.

Factors Affecting Blood Pressure

  • Cardiac output: How fast and strong the heart beats.

  • Vasoconstriction: Narrowing of blood vessels.

  • Vasodilation: Widening of blood vessels.

  • Blood viscosity: Thickness of the blood.

  • Thick blood can cause the heart to work harder.

Diseases and Disorders of the Cardiovascular System

Angina (Chest Pain)

  • Clinical term for chest pain.

  • Caused by myocardial infarction (heart attack).

  • Heart attack: Narrowing of the coronary arteries, leading to blockage.

Atherosclerosis

  • Hardening of the arteries due to plaque buildup.

  • Plaque restricts blood flow, potentially causing blockage, chest pain, and heart attack.

Ischemia

  • Restriction of oxygen-rich blood flow to the heart.

  • Can lead to a heart attack.

Symptoms of a Heart Attack

  • Pain in the chest (squeezing sensation).

  • Pain radiating to the shoulder, arm, neck, and jaw.

  • Shortness of breath.

  • Nausea.

  • Sweating.

  • Dizziness.

  • Always take patient complaints of chest pain seriously.

Hypertension (High Blood Pressure)

  • Caused by narrowing of the arteries.

  • Plaque buildup (atherosclerosis) restricts blood flow.

  • The heart overcompensates, working harder to push blood through.

  • Risk factors: obesity, smoking, kidney disease, excessive alcohol intake, coronary artery disease.

Coronary Artery Disease

  • Narrowing of arteries due to buildup of fat, cholesterol, and plaque.

  • Leads to ischemia (restricted blood flow).

  • Risk factors: high-fat diet, smoking, obesity, sedentary lifestyle.

Aneurysms

  • Balloons that occur within the wall of an artery.

  • Can go undetected for years.

  • Cause: Atherosclerosis.

  • Risk factors: Same as atherosclerosis.

Congestive Heart Failure

  • The heart's ability to pump blood diminishes.

  • Risk factors: high-fat diet, smoking, obesity, sedentary lifestyle.

Mitral Valve Prolapse

  • The mitral valve does not close completely.

  • Causes backflow of blood (regurgitation).

  • May hear a swishing sound instead of the typical "lub dub" heart sound.

  • Causes: Unknown or hereditary.

  • Symptoms: None, shortness of breath, irregularities in rhythm (palpitations).

Thrombophlebitis

  • Blood clots form within the veins of the legs.

  • Risk factors: paralysis, cancer, hormone replacement therapy, sedentary lifestyle, being bedridden.