Download 211 Angina and Myocardial Infarction notes

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Angina and Myocardial Infarction notes
John Miller
Angina: Acute, chronic, or spasm
 Atherosclerosis
o Acute
 Rupture of lesion causes platelet and thrombus formation.
 Causes acute myocardial infarction (AMI) or unstable angina.
o Chronic
 Greater than 75% of lumen occluded
 Fixed (calcified) or fibrotic
 Increased myocardial oxygen demand
 Precipitating factors: exercise, emotion, cold exposure
o Spasm
Angina: Atherosclerotic lesions
o Timeline for Developing Atherosclerosis
 Phase I: Initial lesion and fatty streak (infancy and childhood); Preatheroma (less than
30 years old)
 Phase II: atheroma (30+); fibroatheroma (40+)
 Phase III: complicated lesion: rupture of plaque and thrombi formation with partial
occlusion of vessel (40+); Angina
 Phase IV: more occlusion (40+); unstable angina, MI, sudden death
 Phase V: calcification or fibrosis of lesion; angina; MI
Angina: Collaterals, dilation, occlusion
 Collateral circulation
o More than one artery supplying a muscle.
o Takes time to develop in response to low flow , seen more in older clients.
o Collateral arteries grow and perfuse areas needing more blood, but only in long term disease.
 Coronary arteries usually dilate when need more blood flow.
o Perfuse the heart only during diastole.
o With disease, arteries cannot dilate effectively.
 Most MI's
o Occur with less than 70% occlusion because they are more vulnerable to rupture and thrombosis.
Angina: Patterns
 Stable (classic): stable pattern of characteristics in previous slide, relieved with rest and/or nitroglycerin.
 Unstable (pre-infarction): triggered by unpredictable exertion, increasing in frequency and severity, may
occur at night.
 Spasm: similar to but longer than stable angina, often occurs at night
 Angina: Zones of ischemia, injury, infarction (MI)
 Inner zone is the zone of infarction and necrosis, not reversible.
 Middle zone is hypoxic injury, can infarct or stay ischemic.
 Outer zone is ischemia, which is reversible.
Angina Causes: Increased CO or oxygen need
 Increased cardiac output
o Exercise, emotion, after a large meal
 Increased myocardial need for oxygen
o Hypertrophy
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Angina: Risk factors
 Nonmodifiable risk factors
o Heredity: family history, African American women more at risk than other women.
o Age: early as 20s, symptoms occur after 40, most die after 65, men earlier but women catch up
after menopause
 Contributing risk factors
o Stress
o Homocysteine level: Inflammatory responses that destabilized plaque within the artery wall.
o Menopause
 Estrogen replacement not advised.
Angina: Modifiable risk factors
 Smoking doubles the rate in men and triples the rate in women.
 Hypertension is seen at younger ages in African Americans and is more severe.
 High LDL cholesterol, high triglycerides, low HDL
 Obesity
 Diabetes
 Physical inactivity
 Responses to stress
Angina assessment: Classic
o Onset: quick or slow, related to activity, may think is indigestion.
o Location: most retrosternal or slightly left of the sternum.
o Radiation
 Usually to left shoulder and down upper arm.
 May travel down inner aspect of the left arm to elbow, wrist, inner aspect of 4th and 5th
fingers.
 May travel down to right shoulder, neck, jaw, back or epigastric area.
 Occasionally may only feel the radiation part.
 Rarely is pain located only in a small part of the sternal area.
More classic angina
o Duration: usually less than 5 minutes, after a large meal or anger, may last 15-20 minutes.
o Sensation: squeezing, burning pressure, bursting pressure
o Severity: mild or moderate, discomfort, not pain, rarely severe; less than MI
o Relieving and aggravating factors, treatment
 Relieved by rest and/or nitroglycerin.
 Increased with activity/stress.
 Not relieved by food or antacids;
 Not affected by deep breathing or position change.
Angina assessment: Silent
 Silent Ischemia and Non-Chest Pain
o Most common presentation in many women, elderly, diabetics, Asians and others
o Characteristics: dyspnea, pallor, sweating, faintness, palpitations, dizziness, nausea and vomiting
o Presentation
 Women: epigastric pain, dyspnea, or back pain
 Older adults: dyspnea, fatigue, syncope
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Angina diagnostic tests
 Electrocardiogram (ECG) and exercise electrocardiography.
o May be normal, may have ST elevation or depression
 Scans: CT, MRI
Angina Interventions
 Eliminate chest pain.
o Nitroglycerin SL or spray
 Prevent reoccurrence.
o Antianginal medications prophylactically
 Beta blockers, calcium channel blockers, nitrates (including oral or topical nitroglycerin),
ACE inhibitors
o Heart catheterization (arteriogram) with intervention (angioplasty or atherectomy with stent) to
reduce blockage (PCI).
o Elective coronary artery bypass surgery
Reduce risk factors
 Reduce BP if hypertensive.
 Reduce hyperlipidemia with diet, statins, niacin; low saturated and trans fats
 Exercise and weight control: 30 minutes 5-6 days a week
 Stop smoking
 Control or prevent (Type II) diabetes
Nitroglycerin
 Repeat every 5 minutes if pain not relieved for a total of 3 doses as long as BP greater than 90 systolic or
whatever is ordered
 Keep in a dark bottle without light or moisture for up to six months. Do not keep in bathroom.
 Pain relived by NTG = angina, not MI, radiating or not
 Preinfarction angina = unstable angina, requires hosp. Classic or vasospastic does not
ACE Inhibitors and Calcium Channel Blockers
 Captopril (ACE inhibitor)
o Decreases afterload, increasing contractility and cardiac output, vasodilates and decreases BP.
 Diltiazem (Calicum channel blocker)
 Dilates coronary arteries and decreases pain.
Angina interventions: Teaching
 Heavy pain, not knife like
 Not necessarily having MI
 Pain will occur if I overexert myself
Interventions prior to angioplasty
 Elective (not emergency) procedure
o Permit, teaching, NPO, also sign a consent for emergency coronary artery bypass graft surgery
(CABG)
 Post procedure care
 Similar to arteriogram
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Coronary artery bypass graft (CAB or CABG)
o Open heart
 Heart and Lung Bypass to have blood field for surgery
 Reoxygenates, removes CO2
 Pumps the blood
 Rewarms or cools, filters blood
 Complications
o Bleeding caused by hemodilution and damage to RBCs
o Longer pump times cause more complications.
Heart bypass surgery explained https://youtu.be/YU-AB_THem8
Coronary artery bypass donor graft
 Donor graft
o Internal mammary artery (IMA)
o Saphenous vein
o Radial artery
Off bypass (pump) CABG
 Off bypass CABG, Mid-CABG
o Smaller incision for median sternotomy
o Devices and medications reduce heart movement.
o Less recovery time and cost but outcome may not be as good
o Less complications: ventilation, stroke, atrial fibrillation, pulmonary problems
Minimally Invasive Direct Coronary Artery Bypass (MIDCAB) https://youtu.be/kVc9vXKSh2Q
Surgery Risks
 Women have smaller arteries, may contribute to more complications.
 Non-surgical techniques have reduced need for surgery (angioplasty with stent or medically treated with
medications)
o Survival rates same as medically treated.
Surgery complications
 Same as other surgeries
 Intraoperative stroke
 MI
 Blood clots
 Multiple organ failure
 Death
 Shock
 Postcardiotomy delirium
 Pericardial tamponade
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Preoperative interventions
 Explain details of surgery and recovery
o A&P of heart review
o Arteriogram results discussion with MD
o Prep: antimicrobial shower, shave area
o Ventilator for several hours, suctioning
o Frequent v.s. and other assessments
o Chest tubes, NG tube, foley, multiple IV lines, ECG monitor
o Pain medication, blood transfusions
o Chair 1st POD.
o Noise, short rest periods
 Introduce to staff and recovery / ICU area.
Cardiac surgery preoperative, FHS provider orders
https://www.chifranciscan.org/uploadedFiles/For_Physicians/Provider_Orders/30400016%20CARDIAC%20SU
RGERY%20PREOPERATIVE2016.04.25.pdf
Postoperative interventions: Activity
 Activity
o ICU
 Turned frequently, chair after extubation
o Intermediate Care Unit
 Ambulation 3-4 times per day
 Out of bed for all meals.
o Goals
 Keep systolic BP and HR within parameters to keep graft patent
 No significant dysrhythmias during activity.
 No pain during.
Cardiac surgery postoperative ICU, FHS provider orders,
https://www.chifranciscan.org/uploadedFiles/For_Physicians/Provider_Orders/30400017%20RECEIVING%20C
ARDIAC%20SURGERY2016.04.25.pdf
Interventions in ICU: ECG, other monitoring
 Hemodynamic assessment
o HR, heart chamber pressures: CVP and cardiac output
 ECG
 Intra aortic balloon pump if needed
 Temporary pacemaker
Cardiac surgery PCU postoperative, FHS provider orders,
https://www.chifranciscan.org/uploadedFiles/For_Physicians/Provider_Orders/30400014%20PCU%20TRANSF
ER%20POST%20CARDIAC%20SURGERY2016.04.25.pdf
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Interventions in ICU: Ventilation
 Titrate O2 to 92% saturation
 ABG testing
 Ventilator care, suctioning
 IS and coughing every 1-2 hours
 Morphine IV for pain.
 Splint incision with pillows.
 Ambulate as tolerated after extubation.
Interventions: Perfusion
 Monitor CT output hourly.
o Report more than 100 ml/hour
o Monitor for pericardial tamponade (elevated CVP or JVD; decreased CO, BP; pulsus
paradoxus; muffled heart sounds; sudden stopping of CT drainage)
 Blood, FFP, PLT, crystalloid fluids, colloids to replace volume lost.
o Autotransfusion of banked blood or chest drainage if possible
 Risk of infection
Interventions: Pain
 Differentiate anginal from incisional pain
o Chest and leg incisions
o If coughing or deep breathing increases pain means that it is pleuritic or incisional, not angina
 Administer morphine and other opioids in anticipation of procedures and pain.
Interventions in ICU for complications
 Frequent neurological assessment
o Reorient frequently.
o Explain procedures.
 Secure all lines, prevent client from pulling them out.
 Avoid physical restraints when possible.
 Explain that changes in mental acuity, agitation, confusion, and hallucinations are temporary.
 Organize nursing care to provide adequate sleep.
 Liberalize visitation times with family.
Transmyocardial revascularization surgery
 Channels created with laser on the outside of the heart, which allow muscle perfusion from the
ventricular chamber blood.
 Used for people who cannot have other types of operations.
Acute Myocardial Infarction
(AMI)
 Statistics
o 1 million MI’s yearly in U.S.
 45% of all AMI occur in those younger than 65. 5% occur in those younger than 40.
 50% die before reach hospital, 50% wait more than 2 hours.
 Women have a higher in hospital mortality due to less treatment provided for MI.
 African Americans, Hispanics, Native Americans have higher death rates.
 Acute Coronary Syndrome (ACS)
o Includes angina and MI


Pathophysiology of MI
Transmural infarction
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o
o
Infarct expansion in the first few hours up to 6 weeks.
Remodeling of the ventricle occurs, changing the structure and function.
 Increased with tachycardia, ventricular dilation, increase preload (renin-angiotensin)
 May last for years, causing CHF
Coronary arteries and MI location
 Right coronary artery (RCA)
o Inferior (left ventricular) MI
o Right ventricular MI
 Left (main) coronary artery (LCA or LMCA)
o Left circumflex artery (LCX)
 Posterior (left ventricular) MI
 Lateral (left ventricular) MI
o Left anterior descending (LAD)
 Anterior (left ventricular) MI
 Worst prognosis- due to size
 Septal (left ventricular) MI
Clinical manifestations of MI
 Chest pain
o Similar to angina but more severe and unrelieved by NTG.
o May radiate to neck, jaw, shoulder, back, left arm.
o May be present near epigastrium, simulating indigestion.
o Often not present in women, elderly, diabetics.
Other clinical manifestations
of MI
 Seen more in women, diabetics, elderly
 Atypical chest, stomach, back or abdominal pain
 Nausea or dizziness
 SOB, dyspnea
 Unexplained anxiety, weakness, fatigue
 Palpitations, cold sweat, paleness
Assessment: Location of MI
 12 lead ECG
 Angiography
o Will be done with PCI, if performed.
Diagnostic tests: ECG changes
 Stages of changes
o First: ST elevation or depression
o Next: T wave inversion
o Later: large Q waves (normally small or absent)
 May have normal ECG in first few hours after MI.
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Laboratory tests: Elevated enzymes
 Troponin T
o Onset: 3-6 hr, peak: 24 hr, duration: 14-21 days
o Detect MI occurring much earlier.
o troponin T & I have greater sensitivity and specificity than CK-MB.
 Troponin I
o Onset: 7-14 hr, peak: 24 hr
o Extremely sensitive to cardiac muscle.
 CK-MB isoenzyme
o Onset: 3-6 hr, peak: 12-18 hr
o Elevated in PTCA, thrombolytics.
Interventions for MI
 Prior to EMS management: call first, call fast
o Chew aspirin 325 mg. Reduces mortality 23%.
o Elevate head, loosen clothing around neck
o AED ready if available.
 ED / EMS
o Reduced myocardial damage if treat within first hour of chest pain or symptoms (door-datadecision-drug)
 Door to needle time of less than 30 minutes for thrombolytic therapy (start from pain
onset).
 Door to angioplasty time of less than 1 hour.
o Cardiac enzymes and 12 lead ECG within 10 minutes of arrival at the ED.
Interventions for STEMI
 Acute Myocardial Infarction with ST Elevation (STEMI)
o Adjunctive Treatment (not to delay fibrinolytic)
 Beta Adrenergic Blocker IV
 Nitroglycerin IV
 Heparin IV
 Aspirin, low dose, if not getting Fibrinolytics
 ACE inhibitors only after 6 hours and when stable.
Interventions for less than 12 hours since symptoms
 Fibrinolytics (such as Alteplase), door to drug time should be less than 30 minutes.
 If fibrinolytic contraindicated, then angioplasty and stent (PCI: percutaneous coronary intervention) with
cardiac bypass surgery backup. Door to balloon up time should be 90 +/- 30 minutes, with experienced
and high volume facility.
Myocardial Infarction and Coronary Angioplasty Treatment, Animation. https://youtu.be/T_b9U5gn_Zk
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Interventions for more than 12 hours since symptoms
 High risk
 Recurrent symptoms
 Recurrent ischemia
 Depressed LV function
 Widespread EKG changes
 Prior MI, CABG, PCI
o Coronary angiography to see if treatment will be possible
o Treatment
 PCI
 CABG
 Clinically stable
o ICU
o Serial cardiac markers (enzymes), serial EKG, echocardiography to assess LV function
o Start or continue adjunctive treatments
Interventions for non-ST elevated MI (NSTEMI)
 Adjunctive treatment
o Heparin IV
o Glycoprotein IIb, IIIa receptor inhibitor
o Nitroglycerin IV
o Beta Adrenergic Blockers IV
o ACE inhibitors
 Interventions for all MIs
 MONA= morphine+oxygen+nitroglycerin+aspirin
o O2 titrated to 92% or higher pulse oximeter
o ECG monitor: Watch for lethal ventricular dysrhythmias or heart block.
o IV started with labs drawn for Troponin
o Head of bed elevated to increase ventilation, decrease preload (workload on heart)
o Aspirin 325 mg chewed
o Treat pain
 Morphine if pain not relieved by SL nitroglycerin
 Relieves ischemia by reducing sympathetic stimulation and preload causing a
reduced muscle demand for O2.
Interventions to improve perfusion
 Anti-dysrhythmic therapy
 Emergency PCI (PTCA)-Percutaneous Coronary Intervention (angioplasty with stent, atherectomy)
preferred over thrombolytics in medical centers with expertise.
 Emergency coronary artery bypass
Interventions: Thrombolytics (fibrinolytics)
 Alteplase, within 12 hours of pain starting.
 Reperfusion effects
o Normal ECG, relief of pain, ventricular dysrhythmias
 Contraindications: bleeding, CVA, surgery, trauma
 Most common complication: Bleeding
ST Elevation MI (STEMI) Acute Coronary Syndrome (ACS) FHS Provider orders
https://www.chifranciscan.org/uploadedFiles/For_Physicians/Provider_Orders/30400721_FHS_IP_ST_ELEVATI
ON_MI_(STEMI)_ACUTE_CORONARY_SYNDROME_(ACS)_721_2014.pdf
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Complications in MIs: Dysrhythmias
 Golden (first) hour after chest pain is when most die from death producing arrhythmias.
o 1/2 of deaths in MI
 Common types
o Frequent PVC’s to VT to VF to asystole is most common cause of death.
o Heart block or symptomatic bradycardia
Complications in MI: CHF, Shock
 Cardiogenic shock
o From decreased contractility, arrhythmias, sepsis
o Intra aortic balloon pump to decrease afterload
 Heart failure and pulmonary edema (S3)
o 1/3 of all deaths, disables ¼ of men and ½ of women
o Develops in hours or weeks.
Complications in MI: PE, Tamponade
 Pulmonary embolism
o Secondary to inactivity causing DVT
 Recurrent myocardial infarction
o Within a few years
 Ventricular rupture and cardiac tamponade
o Surgery to repair problem if survives.
 Pericarditis
o Infarction rubs against pericardium causing inflammation
Rehabilitation and Education in MI
 Diet changes, with a dietician’s assistance
o Low fat, low sodium, low caffeine
 Weight loss
 Stop smoking.
 Aspirin, beta-blocker, ACE inhibitor, statin for standard drug regimen.
 Cardiac rehab program tailored to specific client needs.
Rehabilitation and Education
 Strengthening the myocardium
o Phase I (inpatient)
o Phase II (immediate outpatient)
 Uncomplicated MI may go home on 4th day if home assistance, follow-up home nursing
and a restful environment are available.
o Phase III (intermediate outpatient)
Rehab in MI: Phase I
 Bedrest for first 24 hours or less, unless complications of heart failure or dysrhythmias.
 Bedside commode
 Clear liquid unless nausea gone
 Passive ROM
 Dangle for brief periods
 Reposition every two hours.
 Reduce visitors and stimulation if needed.
 After first day, may ambulate to chair if no pain, dysrhythmias, or hypotension with dangling.
 Wireless telemetry for ECG monitoring.
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More phase I
 No isometric activity: moving up in bed unassisted, where muscles tense up with breath holding.
 Activity such as bathroom privileges will be increased gradually.
 Supervised walks, working up to 5-10 minutes.
o Monitor HR, BP, fatigue level. HR should not increase more than 25% above resting. BP should
not increase more than 25 mm systolic.
o Dyspnea, chest pain, tachycardia, other dysrhythmias, exhaustion indicate too much activity.
 Client education on A&P, risk factors, management of disease, home activities, behavioral counseling.
 Monitor for electrolyte changes, such as potassium.
 Assess client for complications every 2-4 hours.
 Prevent constipation which can cause Valsalva and vagal stimulation (bradycardia).
Phase II
 Starts 1-2 weeks after discharge, 3 times a week for 2-3 months.
 Goals
o Restore or establish appropriate exercise ability, including leisure and occupational needs.
o Provide additional education and support.
 Dietary counseling
o Meet the psychological needs of client and family.
 Psychologist or social worker
o Closely monitor for complications.
 20-40 minutes sessions with close monitoring for symptoms, assessing the ECG and
V.S., and stress testing.
 Emergency equipment: medications, defibrillator, etc. are available.
More phase II
 Avoid exertion in cold weather, such as shoveling snow.
 Avoid hot baths or prolonged showers.
 Avoid lifting more than 20 pounds.
 Goal for walking is 2 miles in less than 1 hour.
 Supervised exercise at a cardiac rehabilitation center with exercise equipment, complication monitoring,
and education.
 Large muscle exercises (aerobic) for 20-30 minutes 3-4 times a week, with warm up and cool down
periods.
 May be able to return to work after 8-9 weeks.
o Those with stressful or physically demanding jobs may have to work part-time or find less
stressful work.
 Denial, minimization, acceptance
Phase III
 Community exercise program (YMCA, other health clubs)
 Goals
o Maintain or increase exercise abilities.
o Maintain a long term follow up of risk reduction.
o Encourage client responsibility for risk reduction.
 Home exercise is performed between sessions.
Cardiac Rehabilitation Phase II, FHS orders
https://www.chifranciscan.org/uploadedFiles/For_Physicians/Provider_Orders/30400835%20Cardiac%20Reha
bilitation,%20Phase%20II%20(835)2015.12.07.pdf
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Cardiac Rehab Adult Wellness Program, FHS Provider Orders
https://www.chifranciscan.org/uploadedFiles/For_Physicians/Provider_Orders/30400923%20Cardiac%20Reha
bilitation%20-%20Adult%20Wellness%20Program%20(923)2015.12.08.pdf
Sexual activity
 Impotence, premature or delayed ejaculation
o Avoid erectile dysfunction medications if taking other vasodilators.
 Reduced libido (in men and women)
o Possibly be due to medications, depression, or fears by the patient and his or her partner of
precipitating a cardiac event.
 Maximum heart rate during sexual intercourse averages 120 bpm, which is similar to heart rates
associated with other routine activities in and around the house.
 The hemodynamic response is greater with an unfamiliar sex partner, in unfamiliar surroundings, after
eating, or after consuming alcohol.
 Adapting less strenuous positions — for example, using a side-to-side arrangement rather than the
missionary position — can reduce cardiac stress.
 Patients may start sexual activity 2-3 weeks following an uncomplicated myocardial infarction. They must
be instructed to report any untoward symptoms to the physician or to a member of the rehabilitation
team.
Cardiac Rehabilitation http://emedicine.medscape.com/article/319683-overview#a5
Cardiac Rehab: The Patient Experience St. Luke's Heart Health and Rehabilitation Center
https://youtu.be/XfQDFESD3V4