Exam 3 patho - cardiology

Perfusion

Continuous delivery of oxygenated blood to tissues via the cardiovascular system

Ischemia

A state of reduced blood flow to tissues, leading to decreased oxygen delivery. If prolonged, ischemia causes cellular injury or death (infarction).

Preload

Volume of blood stretching the ventricle at the end of diastole

Afterload

Resistance the ventricle must overcome to eject blood

Stroke volume (SV)

Amount of blood pumped from the left ventricle with each beat. SV × HR = cardiac output.

Cardiac output (CO)

Total volume of blood pumped by the heart per minute. (CO = SV × HR). Critical for maintaining perfusion.

Peripheral resistance

Force opposing blood flow in arteries; regulated by vessel diameter and blood viscosity. High resistance increases BP

How perfusion is maintained:

• Heart: Generates pressure and propels blood.

• Vessels: Arteries carry oxygenated blood to tissues; veins return deoxygenated blood

• Blood Volume: Adequate volume maintains pressure and flow

When perfusion fails (ischemia):

• Cellular hypoxia → anaerobic metabolism → lactic acid buildup.

• Organ dysfunction begins (e.g., brain confusion, renal oliguria, myocardial chest pain).

Signs of impaired perfusion:

• Hypotension or hypertension

• Tachycardia or weak pulses

• Pallor or cyanosis

• Delayed capillary refill

• Organ dysfunction (e.g., oliguria, confusion)

Hypertension (HTN)

high blood pressure, persistent elevation of arterial blood pressure

Hypertension pathophysiology

when the arteries stay under too much pressure —this pressure damages blood vessel walls, causes fat buildup (atherosclerosis), and puts extra strain on the heart and kidneys

Hypertension risk factors

Obesity, high salt intake, smoking, diabetes, kidney disease, stress, family history, sedentary lifestyle

Hypertension epidemiology (cause)

~45% of adults in the U.S. are hypertensive; highest prevalence in Black adults and older populations

Hypertension manifestations

Often “silent.” When symptomatic: headaches, dizziness, blurred vision, epistaxis, chest pain

Hypertension complications

Stroke, myocardial infarction, chronic kidney disease, heart failure, aneurysm

Arteriosclerosis

Hardening and loss of elasticity in arterial walls, increasing vascular resistance.

Arteriosclerosis risk factors

Age, hypertension, smoking

Arteriosclerosis manifestations

Elevated BP, decreased arterial compliance

Atherosclerosis

Plaque buildup (lipids, cholesterol) inside arteries → narrowing & obstruction

Atherosclerosis risk factors 

Hyperlipidemia, hypertension, diabetes, smoking, obesity.

Atherosclerosis manifestations

Angina, claudication, cool extremities, weak pulses

Why is atherosclerosis silent?

develops gradually over decades without obvious symptoms until significant vessel narrowing or acute plaque rupture occurs

What are the three peripheral vascular disorders 

• peripheral artery disease (PAD)

• chronic venous insufficiency (CVI)

• deep vein thrombosis (DVT)

Peripheral artery disease (PAD) primary problem

Arterial narrowing ↓ blood flow to limbs.

Peripheral artery disease (PAD) risk factors

Smoking, diabetes, hyperlipidemia

Peripheral artery disease (PAD) key manifestations

Intermittent claudication, weak pulses, cool skin, non-healing ulcers.

Chronic Venous insufficiency (CVI) primary problem 

Valve failure → blood pooling.

Chronic Venous insufficiency (CVI) risk factors

obesity, pregnancy, prolonged standing

Chronic Venous insufficiency (CVI) key manifestations

Edema, skin discoloration, varicose veins, ulcers

Deep vein thrombosis (DVT) primary problem

clot formation in deep veins

Deep vein thrombosis (DVT) risk factors

Immobility, surgery, cancer, pregnancy

Deep vein thrombosis key manifestations 

Calf pain, swelling, warmth, redness

Why PAD causes claudication: 

Poor arterial flow limits oxygen during activity → ischemic muscle pain

Claudication 

means pain, cramping, or tiredness in the leg muscles that happens when walking or exercising and goes away with rest

What is PAD (Peripheral Artery Disease)?

A condition where the arteries in the legs (or arms) become narrow or blocked, reducing blood flow.

What is CVI (Chronic Venous Insufficiency)

When the veins in the legs can’t return blood back to the heart properly, causing blood to pool in the legs

What is DVT (Deep Vein Thrombosis)

A blood clot that forms in a deep vein, usually in the leg

Why does CVI cause edema?

Venous pooling ↑ hydrostatic pressure → fluid leaks into tissues.

Major risk of untreated DVT

Pulmonary embolism (PE)

Coronary Artery Disease (CAD)

chronic condition of plaque buildup in the coronary arteries

Coronary Artery Disease (CAD) pathophysiology 

Atherosclerosis in coronary arteries → reduced myocardial perfusion → angina or infarction

Decrease myocardial perfusion → ischemia

Coronary Artery Disease (CAD) risk factors

Hypertension, smoking, diabetes, hyperlipidemia, obesity, sedentary lifestyle

Coronary Artery Disease (CAD) epidemiology

Leading cause of death globally. CAD mortality decreasing due to improved prevention and treatment

What characterizes stable angina?

Predictable chest pain with exertion, relieved by rest or nitroglycerin

caused by fixed narrowing of arteries

Acute Coronary Syndrome (ACS)

Unstable angina or MI from plaque rupture and thrombosis, causing sudden decreased blood flow.

sudden complication of CAD

Acute Coronary Syndrome (ACS) manifestations

Chest pain radiating to arm/jaw, SOB, diaphoresis, nausea, palpitations

Heart Failure (HF) pathophysiology

Heart cannot pump effectively → ↓ cardiac output → fluid backs up in lungs or systemic circulation

Heart Failure (HF) causes

Hypertension, CAD, MI, valvular disease, cardiomyopathy.

Heart Failure (HF) epidemiology

Most common in older adults; major cause of hospitalization in >65 age group

Epidemiology

study of the distribution and determinants of health-related states and events in specified populations to control health problems

Left sided HF pathophysiology

Blood backs into the lungs

Left sided HF backwards effect

Dyspnea, crackles, pulmonary edema, cyanosis

Left sided HF forward effects

Fatigue, confusion, weak pulses

Right sided HF pathophysiology 

Blood backs into systemic veins “Rest of body”

Right sided HF backwards effect 

Peripheral edema, JVD, weight gain

Right sided HF forwards effect

Decreased organ perfusion

What are the 3 compensatory mechanisms for heart failure

• RAAS: activation increases blood volume and preload

• SNS: activation raises heart rate and contractility

• Ventricular hypertrophy: increases force of contraction

these mechanisms initially maintain cardiac output but eventually increase myocardial workload and worsen heart failure

Pericarditis cause

Inflammation of the pericardial sac (viral or post-MI).

Pericarditis key signs

Sharp chest pain (better leaning forward), pericardial friction rub

Pericarditis complications

Pericardial effusion → tamponade, constrictive/ chronic/ recurrent pericarditis 

Pericarditis pathology

Inflammation → pericardial layers become tough → friction develops → fluid accumulates → tamponade

Endocarditis cause 

Infection of heart valves → vegetation.

inflammation of the endocardium

Endocarditis key signs

Fever, new murmur, petechiae, splinter hemorrhages

Endocarditis complications

Emboli → stroke, renal infarction, valve destruction, abscess, dysrhythmias, sepsis

Endocarditis pathology

bacteria → attach to valve → form vegetation → interfere with valve function

tricks for PAD

PAD = pain on exertion

tricks for CVI

Chronic Venous Incompetence = swelling

tricks for ACS

abrupt and deadly

trick for atherosclerosis

Plaque makes pipes sticky

tricks for hypertension

high pressure hurts silently

Atherosclerosis: effects and complications

• narrowing of arteries (ischemia)

• plaque rupture (thrombosis, MI, stroke)

• most commonly affected (coronary, carotid, peripheral arteries)

DVT pathophysiology

Virchow’s Triad → Thrombus forms → Clot obstructs flow → Inflammation → Pooling

CAD pain

chest discomfort from reduced oxygen to the myocardium.

PAD pain

muscle cramping from reduced oxygen to the legs during activity

Unstable angina

• Occurs at rest or with minimal exertion
• Increasing frequency, duration or severity
• Not relieved by rest or meds
• Impending MI

Contractility

The strength of the heart muscle’s squeeze

What determines how much blood the heart pumps?

Cardiac Output (CO) = Stroke Volume × Heart Rate

Angina

a type of chest pain caused by a reduced blood flow to the heart muscle.This lack of oxygen-rich blood can cause the heart muscle to become ischemic

Left sided heart failure 

impaired left ventricular output
→ pulmonary effects

Right sided heart failure

impaired right ventricular output
→ systemic venous effects

Systolic heart failure 

reduced contractility, ↓ ejection fraction

Diastolic

second, lower number in BP reading pressure in your arteries when your heart rests between beats

Diastolic heart failure

stiff ventricle, impaired filling, preserved ejection fraction

Systolic

top number in a blood pressure reading, which represents the pressure in your arteries when your heart contracts and pumps blood