the cardiovascular system

The Cardiovascular System

Chapters 15-18

The Heart

• Location:– Thoracic cavity– Behind sternum– Between the lungs

The Heart:

• Protective sac– PERICARDIUM

• Layers of heart tissue– Epicardium– Myocardium– Endocardium

The Heart

• Function– Double pump– Right

• Receives blood from the body (pumps blood to)

• Lungs– Left

• Receives blood from the lungs

• body

The Heart: Blood flow

• Inferior & Superior Vena cava

• Right Atrium – Tricuspid valve

• Right Ventricle – Pulmonary valve

• Pulmonary Arteries – Pulmonary arterioles – Pulmonary capillaries – Pulmonary venules

• Pulmonary veins

The Heart: Blood flow

• Pulmonary veins • Left Atrium

– Bicuspid (mitral) valve • Left ventricle • Aorta

– Aortic Valve• (body)• Arteries• Capillaries • Vein

The Heart: Blood flow

• Veins • Inferior & Superior Vena cava

• Right Atrium

– Tricuspid valve• Right Ventricle • Pulmonary Arteries

– Pulmonary arterioles – Pulmonary capillaries – Pulmonary venules

• Pulmonary veins

Heart Beat

• Lub-dub; lub-dub• First sound– S1 (lub)– “AV valves” close– (valves between the

atriums & ventricles)– Tricuspid– Bicuspid

• Second sound– S2 (dub)– “semilunar valves” close– Aortic valve– Pulmonary valve

Conduction System

• Cardiac muscle does not need the nervous system to generate an electrical impulse

Cardiac Cycle

• Contraction & relaxation of the heart =– One heart beat

• Diastole– Ventricles relax

• Systole– Ventricles contact

Normal Heart Rate

• 70-90 / minute• > tachycardia• < bradycardia

Cardiac output

• Stroke Volume (SV)– Amount of blood pushed

from the heart with each heart beat (ventricle contraction)

– @ 70 mL

• Cardiac Output (CO)– Amount of blood

pumped by the ventricles in 1 minute

• CO = HR (pulse) x SV– @4-8 L/min

Peripheral Vascular System• Network of blood vessels

that carry blood to peripheral tissues and then return it to the heart

• Arteries – carry blood away from the

heart• Capillaries• Veins

– carry blood towards the heart

Arteries & Veins

• Aorta – Arteries

• Arterioles– Capillaries

• Venules– Veins

• Superior & Inferior Vena Cava

Capillaries

• Where Oxygen & nutrients are exchanges

• Very permeable

Blood vessel structure

• Inner layer – Slick surface

• Middle layer– Smooth muscle

• Out layer – Protection

Blood Vessel Structure

• Smooth muscle function– Constriction

• Narrowing– Dilation

• Widening

Blood Vessel Structure

• Veins have something Arteries don’t have!– Valves

Blood Pressure (BP)

• Force exerted by blood against the walls of the arteries

• SYSTOLIC– Pressure exerted when

the heart contracts• DYASTOLIC– Pressure when the heart

is filling

Blood Pressure (BP)

• Optimal Blood Pressure– <120 / 80

Blood

• Oxygenated– Blood that is carrying

oxygen• Deoxygenated– Blood that is not carrying

oxygen– Carrying CO2

Oxygenated & Deoxygenated

• Inferior & Superior Vena cava

• Right Atrium – Tricuspid valve

• Right Ventricle – Pulmonary valve

• Pulmonary Arteries – Pulmonary arterioles – Pulmonary capillaries – Pulmonary venules

• Pulmonary veins

Oxygenated & Deoxygenated

• Pulmonary veins • Left Atrium

– Bicuspid (mitral) valve • Left ventricle • Aorta

– Aortic Valve• (body)• Arteries• Capillaries • Vein

The Heart: Blood flow

• Veins • Inferior & Superior Vena cava

• Right Atrium

– Tricuspid valve• Right Ventricle • Pulmonary Arteries

– Pulmonary arterioles – Pulmonary capillaries – Pulmonary venules

• Pulmonary veins

Small Group Questions

• Fill in the chart.• Describe blood flow

through the heart & body.

• Where is oxygenated blood and deoxygenated blood found?

Cardiac Assessment

• Health History– Chest pain– Breathing problems

• Short of breath– Changes in energy levels– Medication– Life style

• Alcohol intake• Exercise• Smoking• Illicit drugs

Cardiac Assessment

• Skin Color– Pallor

• Pale– Cyanosis

• Blue

Cardiac Assessment

• Vital Signs• Peripheral pulses• Capillary refill• Edema?• Auscultate the heart

Diagnostic Tests

• Lipid profile– Cholesterol– Triglycerides– High-density lipoproteins

(HDL’s)– Low-density lipoproteins

(LDL’s)

• Assess risk for atherosclerosis & coronary heart disease

Diagnostic Tests

• Serum Cardiac Markers(Cardiac enzymes)– Creatine phosphokinase– CK-MB– cTnT

– cTn1

• Heart muscle cells that are dead or damaged release these proteins.

• Increased levels = heart damage

Diagnostic Test

• Electrocardiogram (ECG)– Record of the electricity

of the heart

Imaging Techniques

• CT scan– 3-D X-ray machine

Imaging Techniques

• MRI scan– Magnetic resonance

imaging

MRI: Rules

• No METAL in the room with the machine

• Assess for – Metal implants– Claustraphobia

• http://www.youtube.com/watch?v=7g5UVrOt2CI

• http://www.youtube.com/watch?v=6BBx8BwLhqg&NR=1

Imaging Techniques

• Angiography– INVASIVE

• Insertion into an artery– X-rays + fluoroscopy

Imaging Techniques

• Angiography– INVASIVE– Risks – • Bleeding• Clot

– Assess:• Insertion site• Pedal pulses

WARNING: Angiography

–Closely monitory the client, the insertion site, the extremity after the procedure. Immediately report evidence of bleeding, pain or a pale pulseless extremity to the charge nurse & physician

Coronary Heart Disease

• AKA– Coronary Artery Disease

• Definition– Narrowing of the

arteries that supply blood to the heart muscles

Arteriosclerosis & Atherosclerosis

Arteriosclerosis• Arteries that are

– Thick– Non-elactic

Atherosclerosis• Plaque buildup in the

arteries• #1 cause of CHD

CHD: Risk Factors

Changeable• Smoking• Obesity• Physical inactivity• High fat diet• High blood pressure

– Hypertension / HTN• High blood lipids

– Hyperlipidemia• Diabetes Mellitus

Non-changeable• Age• Gender• Race• Heredity

Atherosclerosis: Pathophysiology

• Narrow arteries • i blood flow • ISCHEMIA– Not enough blood or

oxygen for their metabolic needs

• Infarction– Tissue death

S&S of atherosclerosis

• No symptoms until 75% of the lumen is occluded

• Symptoms are due to ISCHEMIA

Atherosclerosis: IDT Interventions

• Quit smoking• Diet– Low fat

• Exercise• Control BP• Control DM

Atherosclerosis: IDT Interventions

• Medications– Cholesterol-Lowering

Drugs• Statins

– Lipitor– Lescol– Mevacor– Pravachol– Crestor– Zocor

• Nursing Implications– Monitor serum lipid

levels– Assess liver

Angina Pectoris

• “Chest pain when there is a temporary imbalance between myocardial blood supply and demand”.

• Chest pain due to i blood/ oxygen to the heart muscle

Angina Pectoris: S&S

• Pain– Chest– Radiating to

• Neck• Shoulder• Arm • Jaw

– Tight, squeezing, heavy• Shortness of Breath

(SOB)

IDT: Angina Pectoris

• WARNING!!!!

IDT: Angina Pectoris

• Medications– Nitrates– Beta Blockers– Calcium Channel

blockers

Nitrates

• Action:– Dilate blood vessels – h blood flow to the

heart• E.G.– Nitroglycerin

• Route– Sub-lingual– Patches– Ointment

Beta-Blockers

• Decrease workload of the heart

• Nrs Implications– Take BP & pulse before– Hold if <50/min

Calcium Channel Blockers

• Purpose– Treat angina and HTN

• Nrs. Implications– BP & pulse before– Hold if < 50/min

Myocardial Infarction (MI)

• AKA: Heart attack• i blood / oxygen to the

heart muscle • Ischemia • Infarction / necrosis • i cardiac output• Death

Myocardial infarction: S&S

• Chest pain• Tachycardia• Short of breath– Dyspnea

• Skin: cool, clammy• Diaphoresis• Anxiety• N&V

IDT: Myocardial Infarction

• IV (for meds)• Oxygen (via nasal

cannula)• Bed Rest

Meds: Myocardial Infarction

• Aspirin– Thins the blood

• Fibrinolytic agents– Drugs that dissolve clots

• Pain reliever– Nitroglycerin– Morphine sulfate– Relax blood vessels

vasodilation h blood flow

Heart Failure

• “Inability of the heart to function as a pump to meet the needs of the body”

Left-side heart failure

• i cardiac output• h pulmonary

pressure (backs up)

S&S: Left Sided Heart Failure

• Activity intolerance• Short of breath• Orthopnea• Cough• Crackles

Right-side heart failure

• h venous pressure • Edema

S&S: Right-Side Heart Failure

• Activity intolerance• Edema• Jugular vein distention

Medications: Heart Failure

• Diuretics– Furosemide / Lasix– Action

• h urine output

• Positive Inotropic Agents– Digoxin / Lanoxin

• h contractility (heart contraction strength)

Hypertension

• AKA: – high blood pressure

• BP – > 140 systolic– > 90 diastolic

• Pg 430 - 438

Hypertension: Risk Factors

Changeable• Diet

– High Na+– Low K+

• Obesity• Smoking• Alcohol (excess)• Stress• Diabetes

Non-changeable• Family history• Age• Race

Hypertension: S&S

• “The Silent Killer”– H/A– Blurred vision

IDT Tx: Hypertension

• Monitor BP • No Caffeine• No smoking• Lifestyle changes– Diet– Alcohol / Smoking– Physical Activity– Stress reduction

Hypertension: Rx

• Broad classification– Anti-hypertensives

Hypertension: Rx

• ACE inhibitors – (angiotensin-converting

enzyme)– Blocks formation of

angiotensin II • vasodilation

– Blocks aldosterone• i fluid volume

Hypertension: Rx

• Beta-blockers– i the heart rate– i contractility –

• i cardiac output

Hypertension: Rx

• Calcium Channel blockers– Block Ca+ channels in

arterial smooth muscle – Vasodilation

Hypertension: Rx

• Diuretics– h urine output – i fluid volume

Venous Thrombosis

• Thrombo = clot• -osis = abnormal condition• Blood clot (forms on the

wall) of the vein – blockage of blood flow

back to the heart

• Pg 448 - 454

Thrombophlebitis

• Thrombo = – Clot

• Phlebo – Vien

• -itis– Inflammation

• Inflammation caused by clot in the vien

Venous thrombosis

• 3 Factors– Venous stasis

• Slow blood flow– h blood coagulation– Vessel wall injury

Venous thrombosis

• Blood returns to the heart through collateral vessels

Venous thrombosis

• Thrombus (thrombi) may break loose – Embolus (emboli)

• Thrombi =– Stationary

• Emboli– Mobile

Deep Vein Thrombi: S&S

• Most common place– Calf

Deep Vein Thrombi: S&S

• Calf pain• Muscle tenderness• Enlarged calf• h temperature

Deep Vein Thrombi: Complications

• Pulmonary embolism– Clot that travel to the

lung – Blocks the pulmonary

artery

Deep Vein Thrombi: Dx

• Doppler ultrasonography– Used to visualize the

vein and blood flow

Deep Vein Thrombi: Rx

• NSAID’s• Anticoagulants• Fibroinolytic drugs

Deep Vein Thrombi: Rx

• NSAID’s– i inflammation

Deep Vein Thrombi: Rx

• Anticoagulants– Prevent blood clotting– E.G.

• Heparin• Warfarin (Coumadin)

– S/E• Bleeding

Deep Vein Thrombi: Rx

• Fibrinolytic drugs– Breaks up clots– S/E

• Bleeding / hemorrhage