Home > Articles > Professional Certifications > NCLEX-PN

This chapter is from the book

This chapter is from the book

Myocardial Infarction

When there is a blockage in one or more of the coronary arteries, the client is considered to have had a myocardial infarction. Factors contributing to diminished blood flow to the heart include arteriosclerosis, emboli, thrombus, shock, and hemorrhage. If circulation is not quickly restored to the heart, the muscle becomes necrotic. Hypoxia from ischemia can lead to vasodilation of blood vessels. Acidosis associated with electrolyte imbalances often occurs, and the client can slip into cardiogenic shock. The most common site for a myocardial infarction is the left ventricle. Classic signs of a myocardial infarction include substernal pain or a feeling of heaviness in the chest. However it should be noted that women, elderly clients, and clients with diabetes may fail to report classic symptoms. Women might tell the nurse that the pain is beneath the shoulder or in the back, anxiety, or a feeling of apprehension and nausea.

The most commonly reported signs and symptoms associated with myocardial infarction include

  • Substernal pain or pain over the precordium of a duration greater than 15 minutes
  • Pain that is described as heavy, vise-like, and radiating down the left arm
  • Pain that begins spontaneously and is not relieved by nitroglycerin or rest
  • Pain that radiates to the jaw and neck
  • Pain that is accompanied by shortness of breath, pallor, diaphoresis, dizziness, nausea, and vomiting
  • Increased heart rate, decreased blood pressure, increased temperature, and increased respiratory rate

Diagnosis of Myocardial Infarction

The diagnosis of a myocardial infarction is made by looking at both the electrocardiogram and the cardiac enzymes. The following are the most commonly used diagnostic tools for determining the type and severity of the attack:

  • Electrocardiogram (ECG), which frequently shows dysrhythmias
  • Serum enzymes and isoenzymes

Other tests that are useful in providing a complete picture of the client's condition are white blood cell count (WBC), sedimentation rate, and blood urea nitrogen (BUN).

The best serum enzyme diagnostic is the creatine kinase (CK-MB) diagnostic. This enzyme is released when there is damage to the myocaridium. The Troponin T and 1 are specific to striated muscle and are often used to determine the severity of the attack. C-reactive protein (CRP) levels are used with the CK-MB to determine whether the client has had an acute MI and the severity of the attack. Lactic acid dehydrogenase (LDH) is a nonspecific enzyme that is elevated with any muscle trauma.

Management of Myocardial Infarction Clients

Management of myocardial infarction clients includes monitoring of blood pressure, oxygen levels, and pulmonary artery wedge pressures. Because the blood pressure can fall rapidly, medications such as dopamine is prescribed. Other medications are ordered to relieve pain and to vasodilate the coronary vessels—for example, morphine sulfate IV is ordered for pain. Thrombolytics, such as streptokinase, will most likely be ordered. Early diagnosis and treatment significantly improve the client's prognosis.

Clients suffering a myocardial infarction can present with dysrhythmias. Ventricular dysrhythmias such as ventricular tachycardia or fibrillation lead to standstill and death if not treated quickly.

Ventricular Tachycardia

Ventricular tachycardia is a rapid rhythm absence of a p-wave. Usually the rate exceeds 140–180 bpm. A lethal arrhythmia that leads to ventricular fibrillation and standstill, ventricular tachycardia is often associated with valvular heart disease, heart failure, hypomagnesium, hypotension, and ventricular aneurysms. Figure 13.3 shows a diagram demonstrating ventricular tachycardia.

Figure 13.3

Figure 13.3 Evidence of ventricular tachycardia.

Ventricular tachycardia is treated with oxygen and medication. Amiodarone (Cordarone), procainamide (Pronestyl), or magnesium sulfate is given to slow the rate and stabilize the rhythm. Lidocaine has long been established for the treatment of ventricular tachycardia; however, it should not be used in an acute MI client. Heparin is also ordered to prevent further thrombus formation but is not generally ordered with clients taking streptokinase.

Ventricular Fibrillation

Ventricular fibrillation (V-fib) is the primary mechanism associated with sudden cardiac arrest. This disorganized chaotic rhythm results in a lack of pumping activity of the heart. Without effective pumping, no blood is sent to the brain and other vital organs. If this condition is not corrected quickly, the client's heart stops beating and asystole is seen on the ECG. The client quickly becomes faint, loses consciousness, and becomes pulseless. Hypotension or a lack of blood pressure and heart sounds are present. Figure 13.4 shows a diagram of the chaotic rhythms typical with V-fib.

Figure 13.4

Figure 13.4 Ventricular fibrillation diagram.

Treatment of ventricular fibrillation is to defibrillate the client starting with 200 Joules. Three quick, successive shocks are delivered with the third at 360 Joules. If a defibrillator is not readily available, a precordial thump can be delivered. Oxygen is administered and antidysrhythmic medications such as epinephrine or atropine. If cardiac arrest occurs, the nurse should initiate cardiopulmonary resusicitation. (Please visit the American Heart Association guidelines for CPR).

Cardiac catheterization is used to detect blockages associated with myocardial infarctions and dysrthymias. Cardiac catheterization, as with any other dye procedure, requires a permit. This procedure can also accompany percutaneous transluminal coronary angioplasty. Prior to and following this procedure, the nurse should

  • Assess for allergy to iodine or shellfish.
  • Maintain the client on bed rest with the leg straight.
  • Maintain pressure on the access site for at least 5 minutes or until no signs of bleeding are noted. Many cardiologists use a device called Angio Seals to prevent bleeding at the insertion site. The device creates a mechanical seal anchoring a collagen sponge to the site. The sponge absorbs in 60–90 days.
  • Use pressure dressing and/or ice packs to control bleeding.
  • Check distal pulses because diminished pulses can indicate a hematoma and should be reported immediately.
  • Force fluids to clear dye from the body.

If the client is not a candidate for angioplasty, a coronary artery bypass graft might be performed. The family should be instructed that the client will return to the intensive care unit with several tubes and monitors. The client will have chest tubes and a mediastinal tube to drain fluid and to reinflate the lungs. If the client is bleeding and blood is not drained from the mediastinal area, fluid accumulates around the heart. This is known as cardiac tamponade. If this occurs, the myocardium becomes compressed and the accumulated fluid prevents the filling of the ventricles and decreases cardiac output.

A Swan-Ganz catheter for monitoring central venous pressure, pulmonary artery wedge pressure monitor, and radial arterial blood pressure monitor are inserted to measure vital changes in the client's condition. An ECG monitor and oxygen saturation monitor are also used. Other tubes include a nasogastric tube to decompress the stomach, a endotracheal tube to assist in ventilation, and a Foley catheter to measure hourly output.

Following a myocardial infarction, the client should be given small, frequent meals. The diet should be low in sodium, fat, and cholesterol. Adequate amounts of fluid and fiber are encouraged to prevent constipation, and stool softeners are also ordered. Post-MI teaching should stress the importance of a regular program of exercise, stress reduction, and cessation of smoking. Because caffeine causes vasoconstriction, caffeine intake should be limited. The client can resume sexual activity in 6 weeks or when he is able to climb a flight of stairs without experiencing chest pain. Medications such as Viagra are discouraged and should not be taken within 24 hours of taking a nitrate because taking these medications in combination can result in hypotension. Clients should be taught not to perform the Valsalva maneuver or bend at the waist to retrieve items from the floor. The client will probably be discharged on an anticoagulant such as enoxaparin (Lovenox) or sodium warfarin (Coumadin); however this range varies from one text to another.

Pearson IT Certification Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from Pearson IT Certification and its family of brands. I can unsubscribe at any time.


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about Pearson IT Certification products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information

To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.


Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites; develop new products and services; conduct educational research; and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.


If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information

Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.


This site is not directed to children under the age of 13.


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information

If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.


Users can always make an informed choice as to whether they should proceed with certain services offered by Adobe Press. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.pearsonitcertification.com/u.aspx.

Sale of Personal Information

Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents

California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure

Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact

Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice

We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020