Lecture 8 - Alterations in the Cardiovascular System (Part 1)

Alterations in Cardiovascular Function

caused by…

• Genetic

• Neurohumoral

• Inflammatory

• Metabolic mechanisms

Alterations in Cardiovascular Function

Progression…

Cellular abnormalities → tissue dysfunction → organ dysfunction

Tell me all the diseases of the veins

1. varicose veins

2. chronic venous insufficiency

3. deep vein thrombosis (DVT)

4. post-thrombotic syndrome

Tell me all the diseases of the arteries

1. hypertension

2. orthostatic hypotension

3. aneurysm

4. embolism

Varicose Veins

a. what is it?

b. Leads to:

c. Key mechanism:

d. Causes of this?

e. Cellular changes:

a. pooling of blood in veins

b. Leads to:

• Distortion

• Leakage

• ↑ hydrostatic pressure

• Inflammation

c. Key mechanism:

• Hydrostatic pressure inside vein > outside

• Slow venous return

d. Causes:

• Incompetent one-way valves

• Venous obstruction

• Decreased skeletal muscle pumping

• Prolonged sitting/standing

e. Cellular changes:

• Altered prostacyclin : thromboxane A₂ ratio

• ↑ fibroblast growth factor

• ↑ TGF-β

Chronic Venous Insufficiency

a. what is it?

b. Clinical signs:

c. Treatment:

d. Advanced options:

a. what is it?

• Chronic high vein pressure in the legs when standing/walking due to blood pooling.

• Usually progresses from varicose veins

b. Clinical signs:

• Lower-extremity edema

• Skin color changes (pink → red → blue)

c. Treatment:

• Weight loss/Exercise (high yield)

• Reduce sitting & standing

• Leg elevation

• Compression stockings

d. Advanced options:

• Endovenous ablation

• Sclerotherapy

Deep Vein Thrombosis (DVT)

a. what is it?

b. cause what

c. Clinical signs:

d. Prevention:

e. Treatment:

a. what is it?

• Thrombosis = clot

b. cause what?

• If part breaks off → embolus (travels, can cause pulmonary embolism)

• If it blocks the vein → venous obstruction → ↑ venous pressure

  • ↑ pressure + porous/leaky veins → fluid moves out → swelling/edema

c. Clinical signs:

• Unilateral limb involvement is key

• Pain with walking

• Swelling

• Discoloration

d. Prevention:

• Early mobilization

e. Treatment:

• Heparin

• Direct thrombin inhibitors

• Low-dose aspirin

Post-Thrombotic Syndrome

a. what is it?

b. Features:

a. what is it?

• Chronic complication after DVT

b. Features: same clinical signs as DVT

• Only affects the involved limb

• Chronic pain

• Swelling

• Discoloration

How you know for sure it is NOT DVT?

Bilateral swelling

Hypertension

Definition

• Sustained elevation of blood pressure

• Diagnostic threshold:

  • ≥139 systolic OR ≥89 diastolic

Hypertension

Key Mechanisms

• Chronic ↑ cardiac output and/or TPR

  • CO = HR × SV

  • TPR offsets pressure changes:

    • ↑ systolic pressure → ↓ TPR to maintain diastolic

Hypertension

Types

• Primary (essential) hypertension

  • Genetic + environmental

• Secondary hypertension

  • Caused by another disease (renal, pulmonary, etc.)

• Malignant hypertension

  • Rapid onset

  • Diastolic >140 mmHg

Hypertension

Target Organ Damage

• Heart:

  • Cardiac remodeling

  • Hypertrophy

  • Ischemia → MI

• Kidneys:

  • Inflammation

  • Impaired filtration

  • Volume & pH dysregulation

• Brain:

  • Stroke risk

Hypertension

Risk Factors

Easiest way to memorize (quick)

G A S E + S O A N + low K/Mg/Ca

• Genetics, Age, Sex, Ethnicity

• Sodium (high intake), Obesity, Alcohol, Nicotine

• Low electrolytes (K, Mg, Ca)

• Sex:

  • Females >70

  • Males >55

Hypertension

Why Sodium Matters?

• Sodium pulls water into bloodstream

• ↑ blood volume in closed system

• → ↑ pressure

• Chronic intake overwhelms aging kidneys

Hypertension

Clinical Features

• Silent disease

• No early symptoms

• Possible but inconsistent:

  • Frequent urination

  • Nosebleeds

Hypertension

Diagnosis

BP measured:

• On 2 separate occasions

• At each visit, take at least 2 readings ≥2 minutes apart

• Person should be:

- seated

- arm supported at heart level

- rested for 5 minutes

- no caffeine or smoking for 30 minutes before

White coat syndrome

• Nervousness → sympathetic activation

• False elevation

Hypertension

Treatment

• Lifestyle:

  • Exercise/Weight loss

  • Smoking cessation/Limit alcohol

• Drugs:

  • ACE inhibitors

  • ARBs

  • Aldosterone antagonists

  • Diuretics

  • Calcium channel blockers

  • Nitrates (as needed)

 

Orthostatic Hypotension

what is it?

• Drop in BP on standing:

  • ≥20 systolic

  • ≥10 diastolic

Orthostatic Hypotension

what cause it:

• Blood pooling in legs

  • Reduced brain perfusion

Orthostatic Hypotension

Symptoms:

• Lightheadedness

• Fainting

Orthostatic Hypotension

Treatment:

• Increase salt & fluids

• Raise head of bed

• Compression stockings

• Mineralocorticoids

• Vasoconstrictors

Aneurysm

Definition

• Localized dilation/outpouching of vessel or heart wall

Aneurysm

Types

• True aneurysm

  • Involves all 3 vessel layers

• Fusiform

  • Circumferential dilation

• Saccular

  • One-sided bulge

• False aneurysm

  • Clot mimics dilation

• Dissecting aneurysm

  • Blood splits vessel layers

 

Aneurysm

Locations & Effects

• Heart:

  • Dysrhythmias

  • Embolism

• Aorta:

  • Asymptomatic until rupture

  • Catastrophic bleeding

• Thoracic:

  • Dyspnea

  • Dysphagia

• Abdominal:

  • Limb ischemia

Aneurysm

Treatment

• Reduce pressure

• Smoking cessation

• Surgery if severe

Embolism

define

• Circulating bolus that lodges and obstructs blood flow

Embolism

Sources:

• Dislodged thrombus

• Air

• Fat

• Bacteria

• Cancer cells

Embolism

Often originates from:

• Heart (post-MI, valve disease)

Embolism

Effects:

• Ischemia

• Infarction

• Necrosis

Embolism

Clinical signs:

• Pale skin

• Numbness

• Pain distal to blockage