HEART DISORDERS Blood Vessels –Arteriosclerosis –Atherosclerosis Arrythmias Structural Defects –Valve damage –Congenital Infections Congestive Heart Failure.

HEART DISORDERS

• Blood Vessels– Arteriosclerosis– Atherosclerosis

• Arrythmias• Structural Defects

– Valve damage– Congenital

• Infections• Congestive Heart Failure

BLOOD VESSELS

• Arteriosclerosis

• Atherosclerosis

Arteriosclerosis

• All types of arterial damage

• But most often used to describe degenerative changes: wall thickening, hardening & loss of elasticity

• Such as, in diabetics or just older individuals

Atherosclerosis

• Atheroma = plaque: what are the constituents?

• Lipids, cells, fibrin & cell debris, often with thrombi attached

• Describe the steps in plaque formation

Layers of the arteries

and the usual first step in plaque formation

Plaque: fibrous, fatty material & cells

What might be the later effects of this deposit?

atheroma

Deposition of a thrombus & narrowing of the artery

What happens to blood delivery?

• Tissues, e.g. cardiac not enough oxygen

• If the passage is blocked by ½, the amount of blood delivered is reduced to 1/4th.

• Because the area is proportional to the square of the diameter

A 2-layer tunnel with 4 lanes for cars to travel through

Area of a Vessel

• If 4 cars can fit through and the diameter is doubled again, how many cars can pass through?

• 2, 4, 8, 16??

RISK FACTORS

• Non-modifiable

• Modifiable

ANGINA

MYOCARDIAL INFARCTION

Improve Cardiac Circulation

• Arterial Bypass

276 18-13

HEART DISORDERS

• Blood Vessels– Arteriosclerosis– Atherosclerosis

• Arrythmias• Structural Defects

– Valve damage– Congenital

• Infections• Congestive Heart Failure

ARRYTHMIASEctopic Beats and Reentry

Sinus Node Abnormalities

Conduction AbnormalitiesAtrial

Ventricular

AV node

Page 281

Name some causes of dysrhythmic function

• Scar tissue in myocardium

• Electrolyte imbalance, e.g. potassium

• Infections or fever

• Hormonal imbalances

• Drug toxicity

• Heart failure

• Ectopic Beats and Re-entry– What are they?

Review Conduction System

Page 281 18-17

Sinus Node Abnormalities

• Normal Rate: about 70 bpm

• Bradycardia: less than 60– Causes?

• Tachycardia: 100 – 160– Causes?

• Sick Sinus Syndrome

Normal sinus rhythm

TachycardiaPage 282 18-18

Atrial Conduction Abnormalities

• Premature Atrial Contractions, PAC– Ectopic– Re-entry– Palpitations, rapid or irregular

• Causes?

• Flutter: more than 160• Fibrillation: more than 350

• Effects of Atrial Rhythm Changes

Ventricular Conduction Abnormalities

• PVCs– Can they be serious

• Tachycardia– effects

• Fibrillation, uncoordinated quivering– effects

Ventricular Fibrillation

Still 18-18

Heart Block

• Where is it?

• First Degree– increases PR

• Second Degree – periodic missed ventricular beats

• Third Degree, total– How do ventricles continue to contract?

Complete Heart Block

Still 18-18

Treatment

Drugsname some

PacemakerFor which conditions?

DefibrillatorsWhat are they?

18-19

Describe effects of arrythmias

Cardiac Arrest

• What is it?

• What is a short-cut term for it?

• Causes

• Effects

• Emergency Care

HEART DISORDERS

• Blood Vessels– Arteriosclerosis– Atherosclerosis

• Arrythmias• Structural Defects page 290

– Valve damage– Congenital

• Infections• Congestive Heart Failure

Page 288 18-23

Valve Defects

• Where does blood “traffic” get backed up– Stenosis?– Incompetence?

• Back-up effect the sameMitral valve?

Aortic valve?

Still 18-23

Note enlarged right ventricle

Page 289 18-24 B

Effects of Valve Damage

• Arrythmias

• Enlarged Heart

• Poor circulation

• Susceptible to Infective Endocarditis

Infective Endocarditis

• Subacute, low virulence– Strep viridans

• Acute, high virulence– Staph aureus

• Causes

• Effects– Vegetations and progressive valve damage– Emboli

Causes of Valve Damage

• Congenital

• Rheumatic Heart Disease page 291

Page 292 18-26

Usual age group?

Thick cords (what is name for these cords?, what do they do?

Verrucae18-27

Stenosis Fibrous thickening & distortion Commissural Fusion

Still 18-27

Treatment

• Open Heart Surgery – Commissuratomy– Valve Replacement

18-25

Pig heart Replacement valve

New damage includingBlood clot

On mechanicalProstheticValve

Forgot to mention

• Acute Rheumatic Fever– Another after-effect, nervous system

– Causes tics, arm lunges, facial grimaces,etc.– Called Sydenham’s chorea or St. Vitus dance

Congenital Heart Defects

CHF

Blood Vessels

Hypertension

Shock

Peripheral Vascular Diseases

Finish Ch. 18

Congenital Heart Defectspage 288

• Septal Defects

• Dislocations• Valve Defects, already covered

• Tetralogy of Fallot

Continue Heart Defects

1. Review stenosis effects

2. Continue with Tetralogy of Fallot

Still 18-23

Note enlarged right ventricle

Page 289 18-24 B

Page 289 18-24A

Why?

Note enlarged right ventricle

Page 289 18-24 B

Increased pressure on right side

Still 18-24, CWhy is the shunt in the right-to-left direction?

Blood Flowthrough septal defects

May also be called shunts

1. Direction of flow? – why?

2. Cyanotic? – Or Acyanotic?

3. Reduced Blood Volume in Circulation?

Symptoms

• Fatigue• Sleep Difficulties• Feeding Difficulties• Irritability• Squatting Posture• Rapid Heart Beat

• Eventual CHF possible

Pericarditispage 294

• Pericardium, two layers

• Inflammation– swelling– exudate

• Effects– Cardiac tamponade– Adhesions

• Causes

Page 294 18-28 Effects of Pericardial Effusion

CHF

Blood Vessels

Hypertension

Shock

Peripheral Vascular Diseases

Finish Ch. 18

Congestive Heart FailurePp 284 – 288

• What is it?

• Causes?

• Left-sided – why?

• Right-sided – why?– If due to pulmonary disease, called Cor

Pulmonale

Chronic cor pulmonale

Note enlarged rightVentricle with thickened wall

Note

We will not require learning the compensation mechanisms on

p. 285. They are very interesting but too complex for our needs in

this course.

Two Major Pathways of Damage due to CHF

• Forward Effects

• Back-up Effects

Effects of CHF

Forward

Backup

Left-sided Right-sided

Define: dyspnea, orthopnea, paroxysmal nocturnal dyspnea

See Table 18-2 on p. 285

Blood Vessels

Hypertension

Shock

Peripheral Vascular Diseases

Finish Ch. 18

Vasculature

Pp 265 - 269• Arteries • Arterioles

• Capillaries called microcirculation

• Venules• Veins

Vasculature

• Arteries and Veins

• Walls are made up of three layersTunica: intima

media smooth muscle

adventitia elastic and collagen fibers

Veins have thinner walls, less muscle

Veins

• Capacitance Vessels

• Thinner walls & less muscle than arteries

• Blood flow by skeletal muscle, respiratory movements and gravity

• Valves

Vasa vasorum

Tiny blood vessels in the walls of arteries & veins

Supply oxygen to the tissues that make up the walls

Controls

• Autoregulation in arterioles– Conditions?

• SNS, normal constriction

• Norepinephrine, epinephrine, angiotensinincrease constriction

• Precapillary Sphincters

Blood Pressure

• What is it?

• Measurement– How?– 120/75 mm Hg

• What is pulse pressure

• Factors?

Determinants

• Heart contraction

• Blood vessel flexibility

• Blood volume

Controls

• How does body sense bp?

• Sympathetic

• Parasympathetic?

• Hormones: ADH, aldosterone

• Renin-angiotensin-aldosterone

Hypertension

Pp 295 - 297

• 140/90

• Primary, Secondary, Malignant

• Systolic or Diastolic– Elderly, high systolic and low diastolic

Physical Causes

• Blockages and loss of flexibility

• Vasoconstriction– Over-responsive to stimuli– Increased stimulation

• Hormones, stress• Renin-angiotensin, aldosterone cycle

• Hypervolemia

Who is most susceptible• Men more than women until middle age

• Elderly

• African descendants more than caucasians

• Familial predisposition

• Behaviors or personality types

Effects

• Blood vessels– Sclerosis– Aneurysms

• Organs– Brain– Heart– Kidney– Eyes

Principal Dangers

• Can be silent• Treatment & lifestyle changes may not be

consistently maintained

• Stroke• Myocardial Infarction• Long-term damage,e.g. kidney• Aneurysms

Hypertensive heart disease

Note thickened leftVentricular wall

Treatments

• Lifestyle

• Drugs– Diuretics– ACE inhibitors– Blockers: alpha, calcium, beta

Low Blood Pressure

• Also called hypotension

• Sympathetic stimulation not strong

• Some effects?

Shock

Pp 301 - 305• What is it?

• How does it cause its major effects?

• Types– Hypovolemic– Cardiogenic– Changes in peripheral resistance

Shock due to Vasodilation

Anaphylactic

Neurogenic

Septic

Metabolic

Signs

• Thirst• Agitation• Tachycardia• Pale, cool, moist skin

• Or with septic shock may have fever

• Lethargy, dizziness

Treatment

• Treat the primary problemvasoconstrictors, epinephrine, antimicrobials,

Glucocorticoids

• Lie down, cover, keep warm

• Supply oxygen

Effects of Shock

Direct Effects

Compensations

Decompensations

Omit next 2 slides

Effects and compensations of shock are important but complex

Just know that the effects of shock are serious

(you do not need all the detail on pp 302 & 303)

• And they progress rapidly

• And they can cause multiple organ failure

• And death

Last two topics in circulation

• Neurovascular Disease

• Peripheral Vascular Disease

Neurovascular Events

• TIAs

• Stroke - CVA

TIAs

• What?

• Atherosclerosis, small embolus, vasospasm

• Singly or in series

• Compare to angina

Strokes

• What? Compare to MI

factors will be similar

• Causes– Atheroma, embolus, hemorrhage

• Causes of hemorrhage– Hypertension, aneurysm

• Damage related to cause

Peripheral Vascular Diseases

• Aneurysms

• Thromboses

• Peripheral Atherosclerosis

• Raynaud’s Syndrome

• Buerger’s Disease

• Varicose Veins

Aneurysms

Types

Sites & Damage

• Aorta

• Brain

• Sudden hemorrhage

• Thromboses

Peripheral Atheromas

• Where?

• Damage?

• Treatment?

Thromboses

• Which vessels?

• Body locations?

• Travel to?

• Prevention & Treatment

Raynaud’s Syndrome

• What and Where?

• Who?

Buerger’s Disease

• What and Where?

• Who?

• Effects?

• Cigarette Smoking

Varicose Veins

• What?

• Where?

• Dangers?

• Factors?

The End