Coronary Artery Disease/Acute Coronary Syndrome
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Transcript Coronary Artery Disease/Acute Coronary Syndrome
Coronary Heart Disease
NUR -224
Coronary Heart Disease
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Affects 16 million people
Causes more than 600,000 death annually
Caused by impaired blood flow to the myocardium
Accumulation of atherosclerotic plaque in the
coronary arteries usual cause.
• May be asymptomatic or may lead to angina
pectoris, acute coronary care syndrome, myocardial
infarction (MI/heart attack), dysrhythmias, heart
failure and even sudden death
Coronary Atherosclerosis
• Atherosclerosis is the abnormal accumulation
of lipid deposits within arterial walls and
lumen.
• In coronary atherosclerosis, blockages and
narrowing of the coronary vessels reduce
blood flow to the myocardium.
Coronary Heart Disease
Risk Factors
• age (over 50)
• heredity
• smoking
• obesity
• high serum cholesterol levels
• hypertension
• diabetes mellitus
Angina Pectoris
• Characterized by chest pain and usually
precipitated by exercise and relieved by rest.
• Myocardial oxygen needs are greater than
partially occluded vessels can supply,
myocardial cells become ischemic and shift to
anaerobic metabolism
• produces lactic acid that stimulates the nerve
endings in the muscle pain
• Pain subsides when oxygen supply meets
myocardial demand.
Angina Pectoris
• Chest pain reduced coronary blood flow
temporary imbalance between myocardial
blood supply and demand
• This causes temporary/reversible myocardial
ischemia.
• More than 30 minutes of ischemia irreversibly
damages myocardial cells (necrosis)
Types of Angina
Stable angina
Unstable angina
Silent Ischemia
Variant angina (Prinzmetal’s angina)
Stable Angina
• Occurs with a predictable amount of activity
or stress
• Predictable and common
• Occurs when the work of the heart is
increased by physical exertion, exposure to
cold, or by stress
• Sensation may occur neck, jaw, shoulders
• Lasts for few minutes – 5/15 minutes
• Relieved by rest and/or nitrates
Unstable Angina
Occurs with increasing frequency, severity and
duration
Pain is unpredictable and occurs with
decreasing levels of activity or stress and may
occur at rest.
Patients at risk for myocardial infarction
May not be relieved by NTG or rest
Variant Angina (Prinzmetal’s)
• Atypical angina that occurs unpredictably
• Caused by coronary artery spasm with/out
atherosclerotic lesion
• Often occurs at night
Silent Ischemia
• Occurs in the absence of any subjective
symptoms (asymptomatic)
• Patient reports no pain
• May occur with either activity or mental stress
Clinical Manifestations
Chest pain
Precipitated by an identifiable event.
Classic sequence
Women frequently present with atypical
symptoms of angina
Angina Pain
Manifestations
Chest Pain
Quality
Associated manifestations
Atypical manifestations
Precipitating factors
Relieving factors
Assessment/Diagnostic Findings
o Past medical history/family history
o Comprehensive description of chest pain
o Presence of risk factors
o Electrocardiography
o Echocardiography
o Cardiac stress testing
o Cardiac Angiography
Medical Management
Focus on maintaining coronary blood flow and
cardiac function
Measures to restore coronary blood flow
(later)
Pharmacologic therapy
* nitrates
* beta blockers
* calcium channel blockers
* aspirin
Nitrates
• SL NTG -> acute angina attacks (Buccal spray)
• Acts within 1-2 minutes
Long acting nitroglycerin
• Used to prevent attacks not treat an acute
attack.
• Headache, hypotension, nausea, dizziness
• NTG, Nitrostat, Nitro-bid
Nitrates
• Nursing Responsibilities
• Patient Teaching
B –Adrenergic Blockers
Decrease myocardial contractility, HR, BP
which will reduce myocardial oxygen demand
Side effects bradycardia, hypotension,
wheezing, GI complaints.
Contraindicated for patient with asthma
Metoprolol (Lopressor), Atenolol(Tenormin),
Carvedilol (Coreg)
Beta Blockers
Nursing Responsibilities
Patient Teaching
Calcium Channel Blockers
• Decrease the workload of the heart
• Relax blood vessels decrease BP and
increase coronary perfusion
• Potent coronary vasodilator
• Amlodipine (Norvasc), Diltiazem(Cardizem),
Felodipine (Plendil)
• Used to treat Variant Angina
Aspirin
• Prevent platelet aggregation/thrombus
formation
• Reduces the incidence of MI
• 80-325 mg of aspirin as soon as dx. is made
• If patient is taking Tylenol – should continue
to take aspirin
• GI upset – H2 blocker, PPI
Nursing Diagnosis
• Ineffective Cardiac Tissue Perfusion
• Deficient Knowledge
• Risk for Ineffective Therapeutic Regimen
Management
Acute Coronary Syndrome
Condition of unstable cardiac ischemia
Includes unstable angina and acute myocardial
ischemia c/out significant injury of myocardial
tissue
Coronary blood flow is acutely reduced, but
not fully occluded. Myocardial cells are injured
by the acute ischemia that results.
Most people have stenosis of one or more
coronary arteries.
Acute Coronary Syndrome
Cardinal manifestation
Chest pain – substernal/epigastric
Dyspnea
Diaphoresis
Pallor
Cool skin
Tachycardia
Hypotension
Acute Coronary Care Syndrome
Diagnosis
• ECG
• Cardiac Markers
*Cardiac muscle troponins (sensitive indicators
of myocardial damage)
* Creatine Kinase (CK) & CK-MB (specific to
myocardial muscle)
Medications
• Reduce myocardial ischemia
• Reduce risk for blood clotting
• Nitrates
• Beta blockers
• Antiplatelet (po/IV)
Oral Antiplatelet -Medication
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Aspirin
Clopidogrel (Plavix)
Ticlopidine (Ticlid)
Suppress platelet aggregation, prevents the
development of thrombus.
• Nursing responsibilities
• Patient Education
IV Antiplatelet
• Tirofiban (Aggrastat)
• Eptifibatide (Integrilin)
• IV antiplatelets more effective than oral
administered meds but the risk of bleeding is
greater
Heparin
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Prevents the formation of new clots
Reducers the occurrence of MI
IV bolus/then continuous infusion
Infusion based on PTT – 2-2.5 times the
normal PTT value (25-35 sec.)
• LMWH – Lovenox/Fragmin
• All increase the risk of bleeding : bleeding
precautions
Revascularization Procedures
• Several procedures may be used to restore
blood flow and oxygen to ischemic tissue.
Nonsurgical techniques:
• percutaneous coronary revascularization
• coronary atherectomy
• intracoronary stents
• coronary artery bypass graft (surgical
procedure may be used)
Percutaneous Coronary
Revascularization
Is recommended for patients:
• Fail medical management
• Have left main coronary artery/three vessel
disease
• Are not candidates for PCI
• Have failed PCI with ongoing chest pain
Percutaneous Coronary
Intervention
Goal: open the affected artery within 90
minutes of arrival to a facility
Advantages:
• Alternative to surgical intervention
• Performed with local anesthesia
• Patient is ambulatory 24 hours after the
procedure
• Hospital stay shorter
• Patient can return to work
Percutaneous Coronary
Revascularization
• A balloon-tipped catheter is threaded over the
guide wire
• Balloon is inflated for about 30 sec.-2 minutes
to compress the plaque against the arterial
wall
• The stent is then placed over a balloon
catheter and expanded as the balloon is
inflated
• It remains in the artery when the balloon is
removed.
Percutaneous Coronary
Intervention
Post procedure care:
• Assess vital signs
• Bedrest/ flat in bed
• Affected leg straight
• Pressure dressing applied
• Monitor for bleeding/hematoma
• Resume self-care activities/ambulation few
hours after procedure
Percutaneous Coronary
Revascularization
Atherectomy
• Remove plaque from the identified lesion
• Catheter shaves the plaque off vessels walls
using a rotary cutting head - retaining the
fragments in it compartment and removing
them from the vessel.
• Rotation catheter pulverize the plaque into
particles small enough to pass through the
coronary microcirculation.
CABG
• Involves using a section of a vein /artery to
create a connection (bypass) between the
aorta and the coronary artery beyond
construction.
• This allows blood to perfuse the ischemic
portion of the heart.
• Internal mammary artery in the
chest/saphenous vein from the leg are the
vessels most commonly used.
CABG Surgery
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Internal mammary artery – is commonly used.
Remains palliative treatment and not a cure.
Improves quality of life/patient outcomes
Postoperative complications/mortality
increase as a function of age.
• Women have a higher mortality rate than men
CABG
Patient teaching
• Lifestyle changes and reduction of risk factors
• Explore, recognize, and adapt behaviors to
avoid to reduce the incidence of episodes of
ischemia
• Teaching regarding disease process
• Cardiac rehabilitation
• Stress reduction
• When to seek emergency care
Myocardial Infarction
• An area of the myocardium is permanently
destroyed necrosis of the myocardial cells.
If circulation to the affected myocardium is
not promptly restored , the heart loses the
ability to maintain effective cardiac output.
• Life-threatening event
• May lead to cardiogenic shock and death
Myocardial Infarction
• Annually 785,000 experience their first MI
• Majority of deaths from MI occur during the
initial period after symptoms begin:
60% within the first hour
40% prior to hospitalization
• Medical treatment and training in CPR are
vital to decrease deaths due to MI.
Myocardial Infarction
• The area of infarction develops over minute
to hours.
• Cellular ischemia affects conduction and
myocardial contractility
• Myocardial contractility decreases, increasing
the risk for dysrhythmias, subsequently
reducing cardiac output, B/P, and tissue
perfusion
Myocardial Infarction
• When a larger artery is compromised,
collateral vessels connecting smaller arteries
in the coronary system dilate to maintain
blood flow to the cardiac muscle.
• The degree of collateral circulation determines
the extent of myocardial damage.
• Occlusion of coronary artery without any
collateral vessels massive tissue damage
and death
Clinical Manifestations
• Pain – sudden and usually not associated with
activity
• Women/older adults atypical chest pain,
elevated BP & HR initially, then ↓’es
• Nausea/vomiting
• Fever
• Dyspnea, shortness of breath
• Anxiety , sense of impending doom
Collaborative Care
Goals
• Relieve chest pain
• Reduce the extent of myocardial damage
• Maintain cardiovascular stability
• Decrease cardiac workload
• Prevent complications
Assessment/ Diagnostic Findings
• ECG
• Laboratory tests— serum cardiac biomarkers
CK-MB
Myoglobin
Troponin
CBC
Echocardiogram
Laboratory Tests
Serum Cardiac Markers
• Are proteins released into the blood from
necrotic heart muscle
• They occur after cellular death indicates
cardiac damage
• Creatine kinase (CK-MB) and troponin are
measured to diagnose an MI.
Serum Cardiac Markers
Creatine kinase (CK )
• Important enzyme for cellular function
• Found mainly in cardiac muscle (skeletal
muscle/brain)
• Begin to rise rapidly with damage to these
tissues at about 4/6 hours after an MI , peak
at about 12/24 hours and return to normal
within 36/48 hours
• CK correlates with the size of the infarction
Serum Cardiac Markers
CPK-MB
• Subset of CK specific to cardiac muscle
• Most sensitive indicating of MI
• Elevated CK –alone is not specific for MI
• Elevated CPK-MB positive indicator of MI
• Does not normally rise with chest pain from
angina or other causes other than MI
Serum Cardiac Markers
Troponin
• Regulates the myocardial contractility process
• Proteins released during myocardial infarction
– are sensitive indicators of myocardial
damage.
• Necrosis of cardiac muscle, troponins are
released and blood levels rise.
• Is a highly cardiac specific indicator of an MI
• Increases with 4-6 hours during an acute MI,
remains elevated for a long period -- 3 weeks
Serum Cardiac Markers
Myoglobin
• Helps transport oxygen
• Found in cardiac and skeletal muscle
• Levels start to increase within 1-3 hours of
symptom onset return to normal within 24
hours after onset of symptoms.
• Is one of the first cardiac markers to appear
after MI, it lacks cardiac specificity.
• Kidneys rapidly excrete it in urine blood
levels return to normal range within 24 hours.
Ischemia, Injury , Infarction
COMPLICATIONS
• Heart failure
• Cardiogenic shock
• Dysrhythmias and cardiac arrest
Interdisciplinary Care
Immediate treatment goals for the MI
Relieve the chest pain
Reduce the extent of myocardial damage
Decrease the cardiac workload
Prevent complications
Treatment of Acute MI
• Obtain diagnostic tests including ECG within
10 minutes of admission to the ED
• Oxygen
• Aspirin, nitroglycerin, morphine, beta-blockers
fibrinolytic therapy
• Revascularization Procedures
• As indicated: IV heparin, LMWH
• Bed rest
Nursing Interventions
• Pain stimulates the SNS, increasing cardiac
work. Pain relief is a priority.
Acute Pain
Assess for verbal and nonverbal signs of pain
Administer oxygen2-5L/min via nasal cannula
Promote physical and psychologic rest
Titrate IV nitroglycerin as ordered
Administer morphine by IV push for chest pain
as needed
Nursing Interventions
Ineffective Tissue Perfusion
Assess and document vital signs
Assess for changes in LOC
Auscultate heart and breath sounds
Monitor ECG Administer antidysrhythmic
medications
Monitor oxygen saturation
Nursing Interventions
Fear
Acknowledge the client’s perception of the
situation
Encourage questions/ provide consistent,
factual answers
Encourage self-care
Administer anti-anxiety medications as
ordered
Teach non-pharmacologic methods
HEART FAILURE
Heart Failure
• Complex syndrome resulting from cardiac
disorders that impair the ventricles’ ability to fill
and effectively pump blood
• Inability of the heart to pump sufficient blood to
meet the metabolic demands of the body.
• 5.7 million people in the US have heart disease.
• HF is increasing in incidence and prevalence.
• Primarily a disease of older adults.
• HF is associated with high morbidity/mortality
rates
HEART FAILURE
• Heart failure develops cardiac output falls
decrease in tissue perfusion.
• Is a disorder of cardiac function
• Hypertension and CHD are the leading causes of heart
failure
• The prognosis for the client with heart failure
depends on the underlying cause and how effectively
the precipitating factors can be treated.
• Most clients with heart failure die within 8 years of
the diagnosis.
• Ejection fraction – provides information about the (L)
ventricle during systole. Normal 55-65%.
Pathophysiology
• Decrease cardiac output activation of
compensatory mechanisms neurohormonal
response decrease in renal perfusion &
increase vasoconstriction sodium and
water retention fluid overload increase
the workload of the heart
Etiology
• CAD and advancing age are the primary risk
factors for HF
• CAD is found in more than 60% of patients
• Other factors: hypertension, diabetes,
cigarette smoking, obesity,
Manifestations of Heart Failure
• CHD/hypertension are common causes of
L-sided heart failure whereas R- heart failure
caused by conditions that restrict blood flow to
the lungs (acute/chronic pulmonary disease).
Left sided heart failure can lead to right sided
heart failure.
Classification of Heart Failure
Left-sided heart failure
• Most common form of HF
• LV cannot pump blood effectively to the
systemic circulation. Pulmonary venous
pressures increase and result in pulmonary
congestion with dyspnea, cough, crackles, and
impaired oxygen exchange.
• This increase pulmonary pressure
pulmonary congestion and edema
Types of Heart Failure
Manifestation of L-sided heart failure result from
pulmonary congestion (backward effects) and
decreased cardiac output (forward effects).
Fatigue and activity intolerance
Dizziness and syncope
Pulmonary congestion
Cyanosis
Rales/wheezing
Types of Heart Failure
Right sided heart failure
• Causes a back up of blood to the ( R) atrium
• RV cannot eject sufficient amounts of blood
into the pulmonary circulation blood backs
up in the venous system.
• Increase venous pressure causes abdominal
organs to become congested /peripheral
edema develops
• This results in peripheral edema, ® upper
quadrant pain, ascites, anorexia, nausea,
weakness, and weight gain.
Multisystem Effects of Heart
Failure
Neurologic
Respiratory
Cardiovascular
Gastrointestinal
Genitourinary
Integumentary
Metabolic
Diagnostic Studies
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BNP levels – key diagnostic indicator of HF
Serum electrolytes
Liver function tests
Echocardiogram
Chest x-ray
Electrocardiogram
Heart Failure
Hemodynamics Monitoring
Used to assess cardiovascular function in the
critically/unstable client and evaluate their
interventions
Hemodynamic parameters heart rate,
arterial blood pressure, central venous
pressure, pulmonary pressure and cardiac
output
Management of Heart Failure
• Eliminate or reduce etiologic or contributory
factors.
• Reduce the workload of the heart by reducing
afterload and preload.
• Optimize all therapeutic regimens.
• Prevent exacerbations of heart failure.
• Medications are routinely prescribed for heart
failure.
Medications
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Angiotensin-converting enzyme inhibitors
Angiotensin II receptor blockers
Beta-blockers
Diuretics
Digitalis
Other medications
Other Treatment
Surgery
Circulatory
assistance
Cardiac transplantation
Hemodynamic
Monitoring
Complications
Compensatory Mechanism
• Hepatomegaly/splenomegaly
• Dysrhythmias
• Pulmonary problems
Nursing interventions
Decreased Cardiac Output
Excess Fluid Volume
Activity Intolerance
Diet
ACUTE CORONARY SYNDROME
• ACS occurs when ischemia is prolonged and
not immediately reversible resulting in
myocardial cell death .
• The spectrum of ACS encompasses: unstable
angina(UA), non-ST-segment-elevation MI
(NSTEMI), ST-segment-evaluation MI (STEMI).