HEART FAILUREHEART FAILURE

PRESENTED BY JILL KERKMAN

PhysiologyPhysiology

Oxygen-poor blood flows from the body into the right atrium.

Blood flows through the right atrium into the right ventricle.

The right ventricle pumps the blood to the lungs, where the blood releases waste gases and picks up oxygen.

The newly oxygen-rich blood returns to the heart and enters the left atrium.

Blood flows through the left atrium into the left ventricle.

The left ventricle pumps the oxygen-rich blood to all parts of the body.

HEART FAILUREHEART FAILURE

Condition where the heart’s ability to pump the blood has become impaired.

The heart keeps working, but it is working less efficiently.

For individuals with heart failure, the body’s need for oxygen-rich blood is not fully met.

Heart failure usually develops slowly, often over years, as the heart gradually loses its pumping ability and works less efficiently.

HF PhysiologyHF Physiology When the heart doesn’t pump as efficiently as it

should, the blood slows down and less blood is pumped.

The blood returning to the heart backs up in the veins forcing fluid from the blood vessels into the tissues of the feet and legs.

When the heart’s left side, normally receiving the oxygenated blood from the lungs, isn’t pumping effectively, blood backs up into the vessels of the lungs.

How Common is Heart How Common is Heart Failure?Failure?

Estimated 4.8 million Americans have Heart Failure.

400,000 new cases are diagnosed each year. Causes 39,000 deaths a year.

– Contributing factor in another 225,000 deaths. Death rate attributed to heart failure rose by 64%

from 1970 to 1990.– Death rate from CHD dropped by 49% during the same

period. Heart failure mortality is about twice as high for

African Americans as whites for all age groups.– More common among men than women.

Etiology of HFEtiology of HF

CAD MI’s

– Which have scarred heart tissue High BP Valvular Heart Disease Cardiomyopathy Congenital Heart Defects Infection of the Heart

– Endocarditis, Myocarditis, etc. Corrective Mechanisms

Dilated Cardiomyopathy– Involves an enlarged heart ventricle, in which

the muscle thins out rather than becoming thick causing reduced systolic blood pressure.

– Cause is often not known, in which it is called idiopathic dilated cardiomyopathy.

Hypertrophic Cardiomyopathy– The heart muscle becomes thick and contracts

with difficulty. – Some research indicated that this occurs

because of a genetic defect that causes a loss of power in heart muscle cells and, subsequently, diminished pumping strength.

– To compensate for this power loss, the heart muscle cells grow.

Other CausesOther Causes Chronic alcohol abuse Smoking Severe emphysema Excessive salt consumption Hyperthyroidism Thiamin deficiency Pneumonia High fever Liver or kidney failure High cholesterol levels Diabetes and Obesity

Causes Affect the Heart By…Causes Affect the Heart By…

Reducing the strength of the heart’s muscle to contract.

Limiting the ability of the heart chambers to fill with blood.

Filling the heart’s pumping chambers with too much blood.

CompensatingCompensating

The heart compensates to cope with and hide the effects of heart failure. – Enlargement (dilation): Allows more blood

into the heart.– Thickening of muscle fibers (hypertrophy) to

strengthen the heart muscle: Allows the heart to contract more forcefully and pump more blood.

– More frequent contraction: Increases circulation.

PathophysiologyPathophysiologyWhen cardiac output is not sufficient to

meet the metabolic needs of the body, compensatory mechanisms, including neurohormonal responses, become activated.– Mechanisms initially help improve contraction

and maintain circulation but, if continued, lead to abnormal cardiac growth and reconfiguration (remodeling) of the heart.

Renin-Angiotensin-Renin-Angiotensin-Aldosterone SystemAldosterone System

The decreased cardiac output in HF results in decreased renal blood flow.– Activates the release of renin which converts to

angiotensin I, and then angiotensin II, which is a direct vasoconstrictor.

This system promotes fluid retention.

Adrenergic SystemAdrenergic System

Decreased cardiac output causes increased sympathetic activity and increased catecholamines. – Results in vasoconstriction, leading to the

shunting of blood.

TachycardiaTachycardia

This initial compensatory response eventually becomes detrimental, as it increases myocardial oxygen demand and shortens the time for coronary perfusion.

In addition, sympathetic stimulation reduces renal blood flow and stimulates the renin-angiotensin system.

Heart Failure ClassificationsHeart Failure Classifications

I Normal daily activity does not initiate symptoms.

II Normal daily activities initiate onset of symptoms, but symptoms subside with rest.

III Minimal activity initiates symptoms; patients are usually symptom free at rest.

IV Any type of activity initiates symptoms and symptoms are present at rest.

Right Heart FailureRight Heart Failure

Ineffective right ventricular contractile function.

Pure failure of the right side of the heart can occur acutely (as in pulmonary embolus or a right ventricular infarction).

Most commonly caused by left sided failure or severe pulmonary disease.

Left Heart FailureLeft Heart Failure

Disturbance of the contractile function of the left ventricle.

Most frequently caused by left ventricular infarction, hypertension, and aortic and/or mitral valve disease.

Forward FailureForward Failure

Inadequate delivery of blood into the arterial system.

Occurs when systemic vascular resistance is increased, producing decreased blood flow out of the ventricles.

Results in reduced cardiac output and hypoperfusion of vital organs.

Most often occurs with aortic stenosis or systemic hypertension.

Backward FailureBackward Failure

Failure of the ventricle to empty.Usually a result of left ventricular systolic

dysfunction caused by infarction or cardiomyopathy.

Systolic DysfunctionSystolic DysfunctionMore familiar classic type of heart failure.

– Due to the heart’s depressed contractility, a reduction in the force of contraction occurs.

– EF usually drops below 40% (normal 50-70%).– The heart cannot pump with enough force to push a

significant amount of blood into circulation.– Blood coming into the heart from the lungs may back

up and cause fluid to leak into the lungs. Known as pulmonary congestion.

Diastolic DysfunctionDiastolic DysfunctionDue to slowed or incomplete ventricular

relaxation.The heart cannot properly fill with blood

because the muscle has become stiff, losing its ability to relax.

This form may lead to fluid accumulation, especially in the feet, ankles, and legs.

SymptomsSymptoms

DyspneaFatigue EdemaPersistent CoughingRaspy Breathing or Wheezing

PharmacologyPharmacologyACE Inhibitors

– Prevent the production of a chemical that causes blood vessels to narrow.

Inhibits the conversion of angiotensin I to angiotensin II.

– As a result, BP drops and the heart doesn’t have to work as hard to pump blood.

Side Effects– Coughing, skin rashes, fluid retention, excess K+ in

the bloodstream, kidney problems, and an altered or lost sense of taste.

PharmacologyPharmacology

Digitalis– Decreases the force of the heart’s contractions.– Also slows certain fast heart rhythms.– As a result, the heart beats less frequently but

more effectively, and more blood is pumped into the arteries.

Side Effects– Nausea, vomiting, loss of appetite, diarrhea,

confusion, and new heartbeat irregularities.

PharmacologyPharmacology

Diuretics– Help the body to rid itself of extra fluid and

sodium. – Commonly prescribed to reduce high blood

pressure.

Side Effects– Loss of too much potassium, weakness, muscle

cramps, joint pains, and impotence.

PharmacologyPharmacologyBeta Blockers

– Reduce the heart’s workload. – Work on the body’s sympathetic nervous

system, which pours hormones like adrenaline into the bloodstream in response to stress.

– In response to high levels of the hormones, the heart beats faster and has to work harder.

– Patients with heart failure have high levels of these stress-related hormones, a sort of chronic panic mode.

– By blocking that response, beta blockers make the heart beat more efficiently.

PharmacologyPharmacology

Hydralazine– This drug widens blood vessels, easing blood

flow.

Side Effects– May include headaches, rapid heartbeat, joint

pain.

PharmacologyPharmacology

Nitrates– Used mostly for chest pain, but may also help

diminish heart failure symptoms.– Relax smooth muscle and widen blood vessels.– They act to lower primarily systolic blood

pressure.

Side Effects– Headaches.

Exercise TestingExercise Testing

Cardiorespiratory TestingFunctional Testing

– Six minute walk test– Total distance ambulated of less than 985 feet

was associated with poorer short-term and long-term survival in patients having moderate to severe heart failure.

Aerobic Exercise Aerobic Exercise RecommendationsRecommendations

Mode– Most common: walking and cycling

Frequency– Depending on intensity of training, 3-5 times

per week has been shown to be effective in achieving the benefits of exercise testing.

Aerobic Exercise Aerobic Exercise RecommendationsRecommendations

Duration– 20-45 minutes.– Continuous or interval training methods have

been used to achieve training benefits.– Progress slowly to tolerate this duration without

undue fatigue.– Begin with intervals of 2-5 minutes, with 1-2

minutes of rest and progress to longer exercise intervals.

Aerobic Exercise Aerobic Exercise RecommendationsRecommendations

Intensity– Percent of peak VO2– Percent of Heart Rate Reserve– RPE– Rating of perceived dyspnea

Selecting the appropriate method will depend on how an individual patient with heart failure presents clinically.

Resistance Training Resistance Training RecommendationsRecommendations

Shown to be safe and beneficial for Class I-III.– Free weights, pulleys, isokinetics, and weight

machines.– Isometric exercise should be avoided. – Recommended techniques

Borg Scale Acclimation Method

Considerations for Modifying Considerations for Modifying Activities or ExerciseActivities or Exercise

Slow down or stop exercising if the following symptoms develop:– Chest pain– Rapid heart rate– Unusual shortness of breath– Palpitations– Excessive swelling– Irregular or slow heart rate– Weakness, faintness, and dizziness– Leg pain or cramping

Heart TransplantationHeart TransplantationClass III and IV patients are eligible.Usually done on people under age 60.Two year survival rate: 78%

– Five years: 50-70%– 76% of transplant patients are male– 85.4% are white

Highest risk factors for death 3 or more years after transplant:– CAD– Adverse effects of immunosuppressive drugs

Ventricular Assist DevicesVentricular Assist Devices

Bridge to transplantationPermanent supportCapability to support circulation, either

partially or totally, until the heart recovers or is replaced

Ventricular RemodelingVentricular Remodeling

Batista procedureRemoving a section of healthy heart muscle. Reshapes the heart to a normal size and form

and repairs any faulty heart valves. Effective in about 75% of cases.

– If fails, patient must have immediate transplant.

New procedure and not yet widely available.

Dynamic CardiomyoplastyDynamic CardiomyoplastyDetaches one end of a muscle from the back

and wraps it around the ventricles of the heart.

After a few weeks, these relocated muscles are conditioned with electrical stimulation to behave and beat as if they were heart muscles. – Improves systolic pressure, limits dilation of

the heart, and reduces heart muscle stress.

Intra-aortic Balloon PumpIntra-aortic Balloon Pump

Device helpful for maintaining heart function for people waiting for transplants.

May be able to use it safely for somewhat longer periods.– Average duration of 23 days in one study.

Total Artificial HeartsTotal Artificial HeartsProvide complete control of the

cardiovascular system and allow total mobility.

Limited in smaller people– Device may not fit client’s body

Initially were limited to people awaiting transplantation– Being used when there are contraindications to

transplantation, such as advanced age.