Myocarditis

MYOCARDITISGroup 2

INTRODUCTION

Causative agent viral infection,such as parvovirus B19, less

commonly non-viral pathogens such as Borreliaburgdorferi (Lyme disease) or Trypanosomacruzi, or as a hypersensitivity response to drugs.

DEFINITION

The definition of myocarditis varies, but the central feature is an infection of the heart, with an inflammatory infiltrate, and damage to the heart muscle, without the blockage of coronary arteries that define a heart attack (myocardial infarction) or other common non-infectious causes. Myocarditis may or may not include death (necrosis) of heart tissue. It may include dilated cardiomyopathy.

Myocarditis is often an autoimmune reaction. Streptococcal M protein and coxsackievirus B have regions (epitopes) that are immunologically similar to cardiac myosin. After the virus is gone, the immune system may attack cardiac myosin. The consequences of myocarditis thus also vary widely. It can cause a mild disease without any symptoms that resolves itself, or it may cause chest pain, heart failure, or sudden death.

ANATOMY AND PHYSIOLOGY

HUMAN HEART

Hollow, pear-shaped organ about the size of a fist

Made of muscle that rhythmically contracts, or beats, pumping blood throughout the body.

Oxygen-poor blood from the body enters the heart from two large blood vessels, the inferior vena cava and the superior vena cava, and collects in the right atrium

Blood returning from the lungs to the heart collects in the left atrium.

STRUCTURE OF THE HEART

Heart Valves Four valves within the heart prevent blood from

flowing backward in the heart. The valves open easily in the direction of blood flow, but when blood pushes against the valves in the opposite direction, the valves close.

Two valves, known as atrioventricular valves, are located between the atria and ventricles. The right atrioventricular valve is formed from three flaps of tissue and is called the tricuspid valve. The left atrioventricular valve has two flaps and is called the bicuspid or mitral valve

The other two heart valves are located between the ventricles and arteries. They are called semilunar valves because they each consist of three half-moon-shaped flaps of tissue. The right semilunar valve, between the right ventricle and pulmonary artery, is also called the pulmonary valve. The left semilunar valve, between the left ventricle and aorta, is also called the aortic valve.

MYOCARDIUM

Muscle tissue, known as myocardium or cardiac muscle, wraps around a scaffolding of tough connective tissue to form the walls of the heart’s chambers. The atria, the receiving chambers of the heart, have relatively thin walls compared to the ventricles, the pumping chambers. The left ventricle has the thickest walls—nearly 1 cm (0.5 in) thick in an adult—because it must work the hardest to propel blood to the farthest reaches of the body.

PERICARDIUM

A tough, double-layered sac known as the pericardium surrounds the heart. The inner layer of the pericardium, known as the epicardium, rests directly on top of the heart muscle. The outer layer of the pericardium attaches to the breastbone and other structures in the chest cavity and helps hold the heart in place. Between the two layers of the pericardium is a thin space filled with a watery fluid that helps prevent these layers from rubbing against each other when the heart beats.

ENDOCARDIUM

The inner surfaces of the heart’s chambers are lined with a thin sheet of shiny, white tissue known as the endocardium. The same type of tissue, more broadly referred to as endothelium, also lines the body’s blood vessels, forming one continuous lining throughout the circulatory system. This lining helps blood flow smoothly and prevents blood clots from forming inside the circulatory system.

CORONARY ARTERIES The heart is nourished not by the blood passing

through its chambers but by a specialized network of blood vessels. Known as the coronary arteries, these blood vessels encircle the heart like a crown. About 5 percent of the blood pumped to the body enters the coronary arteries, which branch from the aorta just above where it emerges from the left ventricle. Three main coronary arteries—the right, the left circumflex, and the left anterior descending—nourish different regions of the heart muscle. From these three arteries arise smaller branches that enter the muscular walls of the heart to provide a constant supply of oxygen and nutrients. Veins running through the heart muscle converge to form a large channel called the coronary sinus, which returns blood to the right atrium.

FUNCTION OF THE HEART

CARDIAC CYCLE The sequence of events from the beginning of

one heartbeat to the beginning of the next is called the cardiac cycle

The cardiac cycle has two phases: diastole, when the heart’s chambers are relaxed, and systole, when the chambers contract to move blood. During the systolic phase, the atria contract first, followed by contraction of the ventricles. This sequential contraction ensures efficient movement of blood from atria to ventricles and then into the arteries. If the atria and ventricles contracted simultaneously, the heart would not be able to move as much blood with each beat.

During diastole, both atria and ventricles are relaxed, and the atrioventricular valves are open. Blood pours from the veins into the atria, and from there into the ventricles

Next, the ventricles contract, forcing blood out through the semilunar valves and into the arteries, and the atrioventricular valves close to prevent blood from flowing back into the atria. As pressure rises in the arteries, the semilunar valves snap shut to prevent blood from flowing back into the ventricles. Diastole then begins again as the heart muscle relaxes—the atria first, followed by the ventricles—and blood begins to pour into the heart once more.

CARDIAC OUTPUT

The amount of blood pumped by each ventricle in one minute.

Cardiac output is equal to the heart rate multiplied by the stroke volume, the amount of blood pumped by a ventricle with each beat. Stroke volume, in turn, depends on several factors: the rate at which blood returns to the heart through the veins; how vigorously the heart contracts; and the pressure of blood in the arteries, which affects how hard the heart must work to propel blood into them. Normal cardiac output in an adult is about 3 liters per minute per square meter of body surface.

An increase in either heart rate or stroke volume—or both—will increase cardiac output.

During exercise, sympathetic nerve fibers increase heart rate.

At the same time, stroke volume increases, primarily because venous blood returns to the heart more quickly and the heart contracts more vigorously

In a healthy adult during vigorous exercise, cardiac output can increase six-fold, to 18 liters per minute per square meter of body surface.

CAUSES

Myocarditis is an uncommon disorder that is usually caused by viral, bacterial, or fungal infections that reach the heart.

VIRAL INFECTIONS:

Coxsackie Cytomegalovirus Hepatitis C Herpes HIV Parvovirus

BACTERIAL INFECTIONS:

Chlamydia Mycoplasma Streptococcus Treponema

FUNGAL INFECTIONS: Aspergillus Candida Coccidioides Cryptococcus Histoplasma Schistosomiasis

When you have an infection, your immune system produces special cells that release chemicals to fight off disease. If the infection affects your heart, the disease-fighting cells enter the heart. However, the chemicals produced by an immune response can damage the heart muscle. As a result, the heart can become thick, swollen, and weak. This leads to symptoms of heart failure.

OTHER CAUSES OF MYOCARDITIS MAY INCLUDE:

Allergic reactions to certain medications or toxins (alcohol, cocaine, certain chemotherapy drugs, heavy metals, and catecholamines)

Being around certain chemicals Certain diseases that cause inflammation

throughout the body (rheumatoid arthritis, sarcoidosis) In Central and South America, myocarditis is

often due to Chagas disease, an infectious illness that is transmitted by insects.

SIGNS AND SYMPTOMS

Clinical manifestations vary widely but there may be no manifestations at all.

The health history may reveal a recent upper respiratory infections, viral pharyngitis or tonsillitis.

The most frequent manifestations however are: fatigue, dyspnea, palpitation and chest pain.

The client often experiences chest pain as a mild continuous pressure ore soreness in the chest. The chest pain can be distinguish from the effort

induce pain of angina pectoris.

Tachycardia, if present, may be disproportionate to the degree of fever, exertion, or illness

Dysrhythmias can also occur, sometimes producing a fatal circulatory collapse

A pericardial friction rub may occur if the client has pericarditis.

In adults, they can sometimes mimic those of a heart attack - mild to severe pain in the center of the chest, which may radiate to the neck, shoulders, and upper arms.

In severe cases, symptoms include breathlessness, rapid pulse, and heart arrhythmias

In infants, symptoms may also include bluish skin, heart murmurs, and a poor appetite.

RISK FACTORS

Immunodeficient person Who undergone heart transplant Heavy Smokers Alcoholic Obese

COMPLICATIONS

Possible complication includes:heart failuredilated cardiomyopathy and sudden death from lethal

dysrhythmia or Rupture of myocardialaneurysmStrokeIrregular heartbeats (arrhythmias)

LABORATORY

DRUG STUDY

Penicillins:Penicillin G Benzathine

Pregnancy risk: B Drug Class

AntibioticPenicillin Antibiotic

Actions: Bactericidal: Inhibits synthesis of cell

wall of sensitive organisms causing cell death

Indication:Severe infections caused by sensitive

organism (streptococci) Prophylaxis of rheumatic fever

Adverse Effect Lethargy, Anemia, Nausea, Vomiting,

Abdominal Pain, Diarrhea, Pain, Phlebitis at injection site

NURSING MANAGEMENT: Before:

Verify doctors order for drug therapy Identify patientAssess injection site

During:Explain the reason for parenteral routes of

administrationState action of drug for patient’s education

After:Advice patient to report unwanted effects

such as nausea, vomiting, diarrhea, and pain at injection site.

Report difficulty of breathing, rashes, severe diarrhea, severe pain at injection site.

ACE INHIBITOR

Drug name: Enalapril Maleate (Vasotec) Drug Class

ACE inhibitorAnti-hypertensive

Action: Decrease BP, blocks the conversion of

angiotensin I to angiotensin II, decreasiong BP, decreasing aldosterone secretion. In patient with heart failure, peripheral resistance, afterload, preload, and heart size are decrease.

Indication:HypertensionTreatment of Acute and Chronic Heart

Failure Adverse Effect:

Heart AttackDizzinessChest PainPalpitationNausea and VomitingPolyuriaOliguria Fainting

NURSING MANAGEMENT Before:

Verify doctors order about drug therapy Monitor patients vital signs especially BP Identify patient

During: Explain action of drug for patients education Advice to avoid hazardous activities because drugs

may cause dizziness Inform patient that excessive perspiration, vomiting,

and diarrhea After:

Monitor BP Advice patient to change position slowly to minimize

orthostatic hypotension Monitor urinary output Instruct patient to report untoward effect such as

irregular heartbeat and chest pain

CAPTOPRIL(CAPOTEN) Drug class:

ACE inhibitor Anti hypertensive

Action: Block ACE from converting angiotensin

I to angiotensin II, sodium and fluid loss Indication

HypertensionHeart FailureDiabetic nephropathyLeft ventricle dysfunction

Adverse EffectTachycardiaHypotensionAlopeciaRashPhotosensitivityGastric IrritationAnorexiaConstipationFever Chills

NURSING MANAGEMENT Before:

Verify if patient has allergy to captopril Verify doctors order for drug therapy Monitor V/S Take drug 1hr before meals, do not take with food Establish baseline in renal and liver function test before

therapy During:

State action of drug for patients education Avoid activities that may be hazardous

After:

Monitor V/S(BP) Advise patient to inform physician/nurse about excessive

perspiration, dehydration, swelling of hands and feet Monitor weight daily

QUINIDINE

Drug Class Antiarrhythmic Action: Decrease automaticity in ventricle,

decrease height, rate of rise of action potential, decrease conducting velocity, increase fibrillation threshold.

Indication: Atrial arrhythmias, paroxysmal or

chronic ventricular tachycardia

Adverse Effect:PhotophobiaHypotensionNausea and VomitingDiarrhea Liver ToxicityDizzinessFever

NURSING MANAGEMENT: Before

Verify doctors order for drug therapy Identify the patient Have a baseline report of ECG Advice patient not to chew on the tablet Take drug with food Take V/S especially cardiac rate and respiration

During

State action of drug for patient education Do not take grape fruit juice Avoid hazardous activity

After Have an ECG result for evaluation for drug effectiveness Monitor V/S especially cardiac rate and respiration Advise patient to report chest pain, palpitation, and

respiratory difficulties

FUROSEMIDE(LASIX) Drug Class Loop diuretics Action: Inhibits reabsorption of sodium and chloride

from the proximal and distal tubules and ascending limb of the loop of henle leading to the sodium rich diuresis

Indication:Heart failureCirrhosis Renal Disease Acute pulmonary edemaHypertension

Adverse effectDizzinessVertigoHeart AttackDrowsiness FatigueVolume depletionRashNausea and VomitingAnorexiaConstipationPolyuria

NURSING MANAGEMENT Before

Identify if patient has allergy to furosemide Verify doctors order for drug therapy Identify the patient Weight the patient Monitor V/S especially BP Instruct patient to take medication early in the day to

prevent nocturia During

Assist patient in taking the drug or assess injection site State the action of the drug for patients education

After Monitor I/O Weight the patient Assess fluid volume status such as urine color and quality

and specific gravity, skin turgor Advise patient to report hearing loss, ear pain, and tinnitus Monitor I/O especially BP

SURGICAL MANAGEMENT

NURSING MANAGEMENT

Assess patient to gather base line data (ongoing subjective and objective data)

Monitor vital signs Auscultate heart sounds for presence of

friction rub Assess psychosocial data of client Assess base line of nutritional and hydration

data Force fluid intake Encourage to eat nutritious foods

Administer IV antibiotics as prescribe Suggest bed rest Supplemental oxygen maybe prescribe Administer antipyretic agents as prescribe Teach client how to monitor pulse rate and

rhythm Instruct them to report any sudden change in

heart rate, rhythm or palpitations immediately

Encourage family members to take CPR training

NURSING CARE PLAN

ASSESSMENT DIAGNOSIS PLANNING INTERVENTION

RATIONALE EVALUATION

Hyperthermia r/t relaease of endrogeneouspyrogen

After 8 hours of nursing intervention the patient will maintain normal core body temperature.(37c)

> Assess vital signs specially axillary temperature.>cool with tepid bath, do not use alcohol>monitor BP>monitor RR>advise to have adequate fluid intake atleast 2000 cc per day>note presence or absence of sweating as body attempts to increase heat loss by conduction and diffusion.

> provides indication of core temperature.>as it cools the skin to rapidly causing shivering and increase metabolic rate and body temperature.>central hypertension or peripheral or postural hypotension can occurs.>hyperventilation may initially be present but ventilatory may be impaired by seizures, hypometabolicstate(shock and acidosis).>to prevent dehydration..



> administer antipyretics as ordered refrain from use of aspirin products in children>promotes surface cooling by means of droplight >provide highcalorie diet or parenteral nutrition.

> evaporation is decreased by environmental factors by high humidity ambient temperature as well as body factors producing loss of ability to sweat or sweat glands dysfunction.>may cause Reye’s syndrome>heat loss by radiation and conduction cool environment and or fever heat loss by convection.>to meat increase metabolic demand.

ASSESSMENT DIAGNOSIS PLANNING INTERVENTION RATIONALE EVALUATION

Activity intolerance r/t reduced cardiac reserved

The patient will utilize energy conservation technique after 8 hours of nursing intervention

>determine patients perception of causes of active intolerance.>encouraged adequate rest periods especially before ambulation.>assist with ADL.>progress activity gradually such as;1. active ROM exercise in bed progressing to sitting or standing.2. dangling 10-15 min. TID.3. deep breathing exercises TID.4. walking in room 1-2 min. TID.

>guides treatment.>to reduce cardiac woek load.>to reduce energy expenditures>To prevent over exerting the heart to promote attainment of short term goals.>to promotes awareness of when to reduce activity.



5. walking on hall 25 ft., then slowly progressing saving energy for return trip.>teach patient or SO to recognize signs of physical over activity such as fatigue and exhaustion.>teach energy conservation technique.a. sitting to do task.b. changing position frequently.c. storing frequently used items with in easy reachd. resting at least 1 hour after meals before a new activity.>teach appropriate use of environmental aids (bed rails, elevation of head of bed while patient gets out of bed, chair in bathroom).>teach the importance of continued activity once at home.

>to reduced o2 consumption, allowing more prolonged activity >standing requires more work.>distribute work to different muscle to avoid fatigue.>to avoid bending and reaching.>because is energy is needed to digest food.>to conserve energy and to prevent injury from fall.>to maintain strength/ROM endurance game.


Excess fluid volume r/t fluid retention

Will eliminate excess fluid in the body after 8 hours nursing intervention.

>administer diuretics as ordered.>place in a semi-fowlers position as appropriate.>administer IV fluid via infusion pump if possible.>restrict sodium and fluid intake as indicated.>monitor IandO and weight> elevated edematous extremities>instruct client to frequent oral care, chewing gum or hard candy

>to promote fluid diuresis.>to prevent accumulation of fluid>to ensure accurate delivery of iv fluids.>to provide comparative baseline and evaluate the effectiveness of diuretic therapy>to decrease edema>to reduce discomfort of fluid restriction.


Decrease cardiac output r/t altered heart rhythm

After 2-10 shift the patient will demonstrate decrease episodes of dyspnea and display blood pressure stability

>review signs of impending failure /shock, noting decrease for unstable BP/ tachypnea, changes in breath sounds and reduce urinary output.> keep client on bed or chair rest in position of comfort(semi-fowlers position is preferred- legs in 20-30 degrees in shock situation )>administer high flow oxygen via mask or ventilator as prescribed.>monitor cardiacrhythm continuously.>assess urine output hourly or periodically, weigh daily , noting total flow balance.>provide quiet environment.>reiterate a diet restriction as indicated.

>early detection of changes promote timely intervention to limit degree of cardiac dysfunction..>decreases oxygen consumption and risk of decompensation.>to increase oxygen available for cardiac function.>to note effectiveness of medication and or assistive devices.> to allow for timely alterations in therapeutic regimen.>to promote adequate rest periods.>tomaintain adequate nutrition and fluid balance

PATHOPHYSIOLOGY

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Myocarditis