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

Conduction System

• Heart beat is controlled by special cells in the myocardium –“Conduction system”

Conduction Systemhttp://www.youtube.com/watch?v=te_SY3MeWys

• Sinoatrial (SA) node – AKA: Pacemaker

• Internodal pathways • Atrioventricular (AV) node • Bundle of His • Purkinje fibers

Conduction SystemElectorcardiogram (EKG)

• http://www.pennmedicine.org/encyclopedia/em_DisplayAnimation.aspx?gcid=000001&ptid=57

Cardiac Cycle

• Contraction & relaxation of the heart =– 1 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 –@ 70 mL

• Cardiac Output (CO)–Amount of blood

pumped in 1 min.• 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

Capillaries

• Where Oxygen & nutrients are exchanges

• Very permeable

Arteries & Veins

• Aorta – Arteries

• Arterioles– Capillaries

• Venules

– Veins

• Superior & Inferior Vena Cava

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• DIASTOLIC– Pressure when the heart is

filling

Blood Pressure (BP)

• Optimal Blood Pressure–<120 / 80

Blood

• Oxygenated–Blood that is carrying

oxygen O2• 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

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

ECG

• P-wave–Arial

depolarization

ECG

• QRS complex• Ventricular

depolarization

ECG

• T-wave• Ventricular

repolization

ECG

• P-R interval

ECG

• P-R interval• Period of time

from –SA node to–AV node &

Bundle of His

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–Claustrophobia

• 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

• Due to – ISCHEMIA

• Angina• Myocardial Infarction

Atherosclerosis: IDT Interventions

• Quit smoking• Diet– Low fat

• Exercise• Control BP• Control DM

Atherosclerosis: IDT Interventions

• Medications– Cholesterol-Lowering

Drugs• Statins

• Nursing Implications– Monitor • Serum lipid levels• 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

Angina Pectoris: S&S

• Pain– Chest– Radiating to

• Neck• Shoulder• Arm • Jaw

– Tight, squeezing, heavy

• Shortness of Breath– Dyspnea

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– i pulse– i BP

• Action– Block adrenalin– Block renin-angiotensin system

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

Calcium Channel Blockers

• Purpose– Treat angina and HTN

• Action– Relax smooth muscle – Vasodilation

• 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

Angina VS. Myocardial InfarctionAnginaProceeded by: stress or exertionRelieved by: rest & nitroglycerineDuration: < 15 minNOT assoc w/: - N/V- Diaphoresis

Myocardial InfarctionProceeded by: anything (anytime)Relieved by: opioids

Duration: > 30 minAssoc w/- N/V- Diaphoresis- dyspnea

IDT: Myocardial Infarction

• IV (for meds)• Oxygen (via nasal

cannula)• Bed Rest

Meds: Myocardial Infarction

• Aspirin– Thins the blood–Anticoagulant

• S/E–Bleeding–GI upset

Meds: Myocardial Infarction

• Pain reliever–Nitroglycerin–Morphine sulfate–Relax blood vessels –Vasodilation –h blood flow – i pain

Meds: Myocardial Infarction

• Fibrinolytic agents–Drugs that

dissolve clots– S/E• Bleeding

Heart Failure

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

Heart Failure

• What affect will heat failure have on Cardiac Output?–decrease

Heart Failure – compensatory mechanisms

• Cardiac output i• Sympathetic nervous

system –Adrenalin • heart rate• Smooth muscle

contraction

• Cardiac output i• Renin – angiotensin-

aldosterone system– vasoconstriction–Na+ & H2O

retention

Left side heart

• Left heart pumps blood – BODY!

Left-side heart failure

• i cardiac output• h pulmonary

pressure (backs up)

S&S: Left Sided Heart Failure

• Activity intolerance• Dizziness/ syncope• ---------• Short of breath• Orthopnea• Cough• Crackles• Tachycardia

Right side heart

• Right heart pumps blood – Lungs

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

Medications: Heart Failure

• Positive Inotropic Agents– Digoxin / Lanoxin

• h contractility (heart contraction strength)

• i pulse

– Nursing • If pulse < 60 hold med

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”– VAGUE!!– 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

• 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 – Vein

• -itis– Inflammation

• Inflammation caused by clot in the vein

Venous thrombosis

• 3 Factors– Venous stasis– 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– http://

www.youtube.com/watch?v=I0yJTkW9y9s

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)• Aspirin

– S/E• Bleeding

Heparin

• Action–Prevent clot

formation–Prevent clot

growth

• Nrs implications– IV or Sub-cutaneous– Double P dose w/ nrs– Rotate sites – Don’t massage– Report S&S of

bleeding

Heparin

• Antidote–Protamine Sulfate

Coumadin

• AKA:–Warfarin

• Action–Prevent clot

formation–*Requires 3-5 days

to reach effective levels

• Nrs implications– Same time each

day– S&S of bleeding

Coumadin

• Antidote–Vitamin K

Dx Tests

• PT / PTT– Prothrombin time– Partial prothrombin time• Increased =

– Risk for blood clotting

• Decreased– bleeding

Deep Vein Thrombi: Rx

• Fibrinolytic drugs– Breaks up clots– S/E

• Bleeding / hemorrhage

Pulmonary Emboli

Prevention of DVT• Leg exercises• X sitting cross legged • Drink fluids• Anticoagulant therapy

Preventing Complications of Anticoagulant therapy

Hemorrhaging• Wear shoes• Use an electric razor• Use a soft toothbrush• ID band

S&S of anti-coagulant toxicity

• Blood in urine• Blood in sputum– black stools

• Changes in menstrual flow• Easy bruising• Nose bleeds• Bleeding that does not stop

Anticoagulant warning (teaching)

• Avoid aspirin• Lab work on time• If lactating an infant – P baby for S&S too

• Elderly – Close monitoring