Concorde Career College, Portland ST120 Unit 2: The Heart

Concorde Career College, Portland

ST120 Unit 2:The Heart

The HeartObjectives:

Evaluate the anatomic development of the heart

Describe the basic anatomy of the heart, including coverings, wall, chambers, and valves

Trace the flow of blood into, through, and out of the heart

Evaluate myocardial infarctionDescribe the conduction system of the heartDescribe basic cardiac dysrhythmias and

electrocardiogram elements

The Heart: Part of the Cardiovascular System

Cardiovascular (Circulatory)

SystemBloodHeartArteriesVeinsCapillaries

Cardiovascular System

Cardiovascular

Pertaining to the heart and blood

vessels.

Heart Heart the pump

Peripheral vascular system Peripheral vascular system arteries – carry blood AWAY from the heartVeins – carry blood TOWARD the heartcapillaries – tiny webs that connect the arteries

and veins peripherally; gas exchange takes place called internal respirations

The lymphatic system also part of the circulatory system


Function of the Blood Circulatory System-- Simply→ Transportation

Blood TransportsHormonesEnzymesOxygenCarbon dioxide

Carries nutrients (from various organs) and oxygen (from the lungs) to the body’s cells for use, which creates waste

The waste (includes carbon dioxide) is carried from the cells to the excretory organs. Example-Lungs expires carbon dioxide


The Heart

Cardiovascular SystemGeneral Information

Located in the mediastinum

Slightly bigger than a fist

Contracts approximately 72 times per minute

2/3 of the heart is located toward the left of the thoracic cavity

Cardiovascular SystemFunction of the Heart

PumpSystole (contraction)Diastole (relaxation)

Coverings of the HeartPericardium – loose fitting sac that covers

the entire heartSerous pericardium – inside the

pericardium; composed of two layersParietal layer- lines the inside of the

pericardiumVisceral layer- thin layer that covers the

heartPericardial cavity – space located between

the Parietal layer and the Visceral layer; contains pericardial fluid to reduce friction

Pericardium

Heart AnatomyEpicardium is the outer layer of the heart wallEach chamber is lined by a thin layer of tissue called the

endocardiumThe wall of each chamber is composed of cardiac

muscle tissue called the myocardium


Chambers of the Heart

Atria (receiving chambers)

Ventricles (pumping chambers)

Separated into right and left sides by the septum

HEART CHAMBERS

UPPER CHAMBERS – RIGHT AND LEFT ATRIA which receives oxygen poor blood returning from lungs and body

LOWER CHAMBERS – RIGHT AND LEFT VENTICLES moves oxygen rich blood into arteries

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Heart Valves

Tricuspid (right atrioventricular)

Bicuspid (mitral or left atrioventricular)

Pulmonary (semilunar)

Aortic (semilunar)

HEART VALVES

why do we need heart valves? To keep the blood flowing one direction

The valve that separates the right atrium from the right ventricle is called the?

TRICUSPID VALVE

The valve that separates the left atrium from the left ventricle is called the?

BICUSPID VALVE or MITRAL

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Heart ValvesSL or semilunar valves located between the two ventricles

and the arteries that carry the blood away from the heart

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Heart ValvesPulmonary semilunar valve is located at the beginning of the

pulmonary artery that allows blood to flow from the right ventricle to the lungs

Aortic semilunar valve is located at the beginning of the aorta and allows blood to flow out of the left ventricle into the aorta

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Chordae Tendineae

Stabilize valve flaps to promote one way blood flow


Myocardial Blood Supply

Right coronary arteryLeft coronary arteryCircumflex arteryRight marginal branchAnterior and posterior

interventricular arteries

Coronary arteries and Coronary veins

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Blood Flow through the HeartThe right side of the heart receives oxygen-poor

blood from the veins•Blood enters right atrium through the superior vena cava and the inferior vena cava

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Blood Flow through the HeartWhen the heart “beats”, first the atria contract

simultaneously (atrial systole)

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Blood Flow through the HeartThen the ventricles fill with blood and they contract togetherWhen the ventricles contract, blood in the right ventricle is

pumped through the pulmonary semilunar valve into the pulmonary artery and to the lungs, where it is oxygenated

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Blood Flow Through the HeartOxygenated blood returns to the left atrium through 4

pulmonary veinsIt then passes through the left AV or bicuspid valve to the

left ventricle

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Blood Flow Through the HeartFrom the left ventricle, the blood is pumped out

through the aortic semilunar valve to the aortaFrom the aorta to the rest of the body!

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Conduction System

Electrical impulses that signal the heart to beat

All cardiac muscle fibers in each region of the heart are electrically linked together!

Intercalated disks are electrical connectors that join the muscle fibers

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Conduction SystemSinoatrial (SA)

nodeAtrioventricular

(AV) nodeBundle of HisRight and left

bundle branchesPurkinje fibers

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Cardiac Cycle

Each complete heartbeat is called a cardiac cycle

Consists of alternating systole (contraction) and diastole (relaxation) of atria and ventricles

Stroke volume is the volume of blood ejected from the ventricles during each beat

Cardiac output is the volume of blood ejected from the left ventricle into the aorta

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PathologyCoronary Atherosclerotic Heart Disease - a condition

in which fatty material collects along the walls of arteries. This fatty material thickens, hardens (forms calcium deposits), and may eventually block the arteries; endothelial cell dysfunction

Myocardial Ischemia - (reduced blood supply) of the

heart muscle, usually due to the blockage caused by Coronary Atherosclerosis

Angina pectoris – chest pain due to Myocardial Ischemia

Myocardial Infarction (MI) – death of heart muscle tissue from Myocardial Ischemia, which leads to sudden cardiac death

PathologyVentricular fibrillation – major dysrhythmia of the

ventricles. They flutter without coordination which results in lack of blood pumped out of the heart

Heart block – a disease in the electrical system of the heart

Asystole – cardiac arrest

Myocardial rupture – blood escaping the ventricles and entering the pericardial sac; can result in cardiac tamponade

Cardiac aneurysm – ballooning of the ventricular wall resulting in increases pressure in the ventricles

Coronary Atherosclerotic Heart Disease



TreatmentsPreformed in the Cardiac Catheterization

lab (Cath Lab)

Percutaneous Transluminal Coronary Angioplasty (PTCA)

Coronary Stent

Intra-coronary Thrombolysis

Coronary Stent - A Treatment for Coronary Atherosclerotic Heart Disease

Percutaneous Transluminal Coronary Angioplasty (PTCA)

TreatmentsPreformed in the Heart Room in the OR

Suite Coronary Artery Bypass Grafting (CABG)

Permanent pacemaker

Surgical Treatment : Coronary Artery Bypass Grafting (CABG)

Possible Grafts for CABG1. Saphenous vein 2. Internal thoracic arteries (mammary)3. Radial Artery

Saphenous Vein Harvesting

Postoperative Healing

Endoscopic Saphenous Harvesting

Mammary Artery Harvesting

Internal Mammary Artery

Radial Artery Harvesting

Cardiopulmonary BypassIdentify the locations of the tube insertions into the circulatory system

Permanent Pacemaker

Dysrhythmias Sinus Dysrhythmia – most common;

related to vagal nerve impulses to the SA node; benign

Sinus Tachycardia – heart rate of 100 beats or more per minute

Sinus Bradycardia - heart rate of 60 beats or less per minute

Atria DysrhythmiasDysrhythmias originating in the atria:Premature atrial beat – often associated

with stress or consumption of caffeine or nicotine

Atrial tachycardia – atrial rate of 150-250 beats per minute; usually benign

Atrial flutter - atrial rate of 250-350 beats per minute; can result in increased ventricular rate and decrease in oxygen

Atrial fibrillation - atrial rate of 350-600 beats per minute; results in increased ventricular rate and decrease in oxygen

Ventricular DysrhythmiasBenign PVC’s – less than 5 per hour;

absence of heart diseaseComplex PVC’s – greater than 10-30 per

hour; with or without heart diseaseMalignant PVC’s – same as complex except

with left ventricular dysfunction Ventricular tachycardia – 140-250 beats per

minuteVentricular flutter – regular contractions

but at a fast rate of 250-350 per minute

ElectrocardiogramECG or EKG

Electrical signals can be picked up form the body surface and transformed into visible tracings by an instrument called an electrocardiograph

The electrocardiogram is the graphic record of the heart’s electrical activity

ECG3 characteristic deflections or waves

P wave – depolarization (triggers contraction) of atria

QRS complex - depolarization (triggers contraction) of ventricles

T wave - repolarization of ventricles

Cardiothoracic ProceduresFeatures of the ECG Paper

ECG Electrical Correlation

Electrocardiograph(Normal Sinus Rhythm)

Sinus Rhythm

Occasional (Incidental) PVC

Bigeminy(PVC Every Other Beat)

Ventricular Fibrillation(V Fib)

Premature Atrial Contraction(PAC)

Atrial Fibrillation

Asystole

Documents

Concorde Career College, Portland ST120 Unit 2: The Heart