IntroductionSo far you have learned the essential elements of cardiac assessment, and rhythm and ECG analysis. In this section the focus is oncaring for the patient who is suffering acute coronary syndrome. This encompasses myocardial ischemia as well as acute myocardialinfarction (AMI). The nursing responsibilities in caring for a patient experiencing acute coronary syndrome includes community educationfor early symptom recognition, prompt attention and prioritised management in the acute phase, discharge planning and cardiacrehabilitation.Learning outcomes for this sectionUpon successful completion of this section, you should be able to:identify assessment strategies for patients presenting with signs and symptoms of AMIdescribe the differential diagnoses that may present with chest painrelate the pathophysiology of heart disease to the anticipated plan of care for a patient experiencing an acute myocardial infarction(AMI)demonstrate an advanced physiological understanding of medication used in your practice settingplan collaborative care that extends across the health care continuum for patients experiencing an uncomplicated AMI.4/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 4/21ReviewAcute coronary syndromes are most commonly associated with the rupture or erosion of an unstable atherosclerotic plaque andsubsequent formation of a platelet-fibrin thrombus. It is important to understand the pathophysiology of acute coronary syndromesincluding the following:Risk factors for the development of coronary artery disease.Pathophysiology of the development of atherosclerosis.The classifications of the different forms of angina.The ECG characteristics of myocardial infarction from section 4.Acute Coronary Syndrome (ACS) Patho…4/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 5/21Readings (a choice)Core text readingAitken, A, Marshall, A, & Chaboyer, W., chapter 9 ‘Cardiovascular alterations and management’, in ACCCN’s critical care nursing, ElseeReadingsThompson, P 2011, Coronary care manual, 2nd edn, Elsevier, Australia.Chapter 8 ‘Pathophysiology of atherosclerosis’, pp. 54-61.Chapter 9 ‘Pathophysiology of coronary thrombosis’, pp. 62-71. – Click HereChapter 10 ‘Pathophysiology of myocardial infarction’, pp. 72-78.Chapter 16 ‘Biochemical markers of myocardial necrosis’, pp.125-129 – Click HereChapter 60 ‘Prehospital coronary care’, pp. 454-458.Chapter 61 ‘ACS: emergency department care’, pp. 459-466.Chapter 62 ‘ACS: coronary care unit admission and care’, pp. 467-473. – Click HereChapter 63 ‘Management of ST elevation myocardial infarction’, pp. 474-484.Chapter 64 ‘Management of non ST elevation ACS’, pp. 485-493.4/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 6/21ACS in Women and ANZCOR UpdateseReadingMehta, L.S., Beckie, T.M., DeVon, H.A., Grines, C.L., Krumholz, H.M., Johnson, M.N., Lindley, K.J., Vaccarino, V., Wang, T.Y., Watson,Infarction in Women A Scientific Statement From the American Heart Association. Circulation, pp.CIR-0000000000000351. – Click HeWebsiteThere have been some updates from the Australian and New Zealand Committee on Resuscitation (ANZCOR) (Australian ResuscitatiAustralian and New Zealand Committee on Resuscitation: Guidelines Section 14: Acute Coronary Syndromes – Click HereANZCOR Guidelines Update on Acute Coronary Syndromes – Click here4/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 7/21Safety and Quality ACS Clincial Care StandardAustralian Commission on Safety and Quality in Health Care. Acute Coronary Syndromes Clinical Care Standard. Sydney: ACSQHC, 24/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 8/21Classification of acute coronary syndromesIn the previous module you learned the ECG characteristics of acute MI. It is important to distinguish between unstable angina, non STelevation myocardial infarct (NSTEMI) and ST elevation myocardial infarct (STEMI). Patients with symptoms of ischemic discomfort maypresent with or without ST segment elevation on an ECG. Patients who present without ST segment elevation are experiencing eitherunstable angina or NSTEMI. The distinction between these is made by assessment of the presence of elevated serum cardiac markers.The majority of patients with NSTEMI do not develop Q waves (indicating irreparable necrosis) on their ECG and you may hear referred toas having a Non Q wave MI (NQWMI) although this terminology is no longer commonly used. However some patients with NSTEMI dodevelop Q waves on their ECG, (QWMI). Patients experiencing STEMI can also develop Q waves on their ECG with a smaller numberexperiencing NQWMI. With a strong current focus on client early action and early clinical intervention in this cohort of patients the numberof people exhibiting Q waves is decreasing.Figure 5.1: Classification of acute coronary syndromes (Adapted from Thompson, P 2008, Coronary care manual, 2nd edn, ChurchillLivingstone, Australia, and White, HD & Chew, DP 2008, ‘Acute myocardial infarction’, Lancet, vol. 372, pp. 570–584.)The presence of Q waves is often associated with transmural infarction, or one which extends through the full thickness of themyocardium. However, Q waves are not a consistent indicator of transmural infarction. Similarly the presence of ST segment depressionwithout elevation elsewhere on the ECG is usually but not always associated with subendocardial injury. The lack of consistency of ST andQ wave changes as indicators of subendocardial or transmural zones of injury has lead to the classification of acute coronary syndrome bytheir ECG characteristics alone.4/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 9/21Clinical assessment: the patient with chest painActivitySome disorders mimic the chest pain of AMI. Construct a table that describes the pain location, paincharacteristics and common assessment findings such as any ECG changes for each disorder listed below.Disorders that may mimic the chest pain of AMIpulmonary embolism pneumoniaaortic dissection pneumothoraxangina gastric refluxPericarditisApproach to Chest painAn Approach to Chest Pain4/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 10/21Diagnosis of acute myocardial infarctionAcute cardiac care is a dynamic discipline. Research in regard to management strategies including diagnostic tools, drug therapy, invasiveand non-invasive treatments are under constant review by clinicians and researchers. Evidence based practice at this stage supports earlyclinical presentation, cardiac enzymes and ECG changes as the standard for diagnosis of AMI. However, there are circumstances whenfurther intervention such as catheter lab or CT is required to confirm suspected diagnosis.4/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 11/21Clinical presentationThe diagnosis and determination of the severity of an AMI is on a clinical diagnosis which requires a thorough history and physicalexamination.Pain, shortness of breath, diaphoresis are usually the most significant symptoms for most patients experiencing a STEMI or NSTEMI andnormally follow a characteristic pattern. However, some patients with acute coronary syndromes may not experience pain, and theintensity of pain varies with the pain threshold of different patients. The intensity of the pain experienced is neither indicative nor diagnosticof the severity of the ACS the patient may be experiencing.Chest pain may be caused by many different conditions; however, it is important to remember that the patient with chest pain should beconsidered cardiac in origin until proven otherwise. The patient who presents with acute chest pain requires prompt efficient nursing careto help alleviate their suffering and the potential damage to the myocardium.Myocardial Infarction in the ICU setting –4/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 12/21Diagnostic tools and proceduresActivity
Research the clinical signs which are common on presentation with an acute MI. Are there any signs orsymptoms which are common with particular types or zones of infarction?Using your text find the sections that discuss the variety of diagnostic procedures and tools available for thediagnosis and treatment of Acute Coronary Syndromes. The list of investigations below can be performed toassist with the diagnosis and ongoing management of myocardial infarction and heart failure.Chest x-rayECGArterial blood gasesEchocardiograph (two types and why use different methods?)Stress exercise electrocardiographyCardiac catheterisation: angiography and angioplastyComplete blood countSerum electrolytes/liver function tests/complete cholesterol screenRadionuclide studiesMagnetic Resonance ImagingProvide information on why each test/procedure may be performed. (That is, what do you think the team islooking for or treating?) There could be more than one reason.4/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 13/21BiomarkersKnowledge of the purpose and significance of laboratory values assisting in the diagnosis and prognosis of AMI can enhance the quality ofnursing care available to patients. Laboratory studies include routine blood analysis and special studies such as cardiac enzymes.Enzymes are found in all living cells and act as catalysts in biochemical reactions. They are present in low amounts in the serum ofhealthy people. The loss of membrane integrity in myocardial cells undergoing necrosis allows intracellular molecules to diffuse out intothe cardiac interstitium and subsequently the blood stream. Detection of the abnormal presence of biomarkers is the ultimate diagnosticcriteria for distinguishing between unstable angina and NSTEMI. Some cardiac enzymes are present in other organs, so elevation of theseenzymes is not always an indicator of cardiac damage.A biomarker, known as Troponin or, in correct terminology, ‘cardiac Troponin’ was discovered in the 1990’s and is used successfully todayfor assisting in the diagnosis of cardiac muscle damage. There are three different types of Troponin; Troponin I (TnI), Troponin C (TnC)and Troponin T (TnT), with Trop I and T used for detection of damage specifically to the cardiac muscle. Troponin is a protein consisting ofthree sub-units and plays a key role in muscle contraction alongside actin and myosin. These are known collectively as contractileproteins.ActivityConsult the section on biomarkers in your prescribed text to find the answers to the following questions.Describe how Troponin (T/I) differs from existing cardiac enzymes, namely creatine kinase (CK), and theisoform of creatine kinase (CK-MB).Compose a table that lists all of the current biomarkers associated with AMI, the time they take to peak, andthe duration of elevation.Consider how these and other investigations might be of some benefit in the diagnosis of myocardialinfarction. Your list should include procedures such as laboratory assessments.It is important to note that the initial diagnosis of STEMI can be made by clinical and ECG criteria alone.It is not necessary to wait for results of biochemical markers to arrive before initiating therapy in patientsat risk.4/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 14/21Management of the patient with acute coronary syndromesNational Heart Foundation of Australia WebsiteFor professionals: Australian acute coronary syndromes – Click HereAustralian acute coronary syndromes capability framework – Click HereManaging the patient with an acute coronary syndrome is an exciting area of clinical practice where you can really make a positivedifference to patient and family outcomes.In the 1960’s specialised Coronary Care Units were introduced to hospitals across the world to offer closer monitoring and access ofpatients to specialty trained nursing staff and subsequently enhanced treatment of patients admitted with a myocardial infarction. Deathrates due to pump failure or arrhythmia actively decreased and the focus turned to pre-hospital coronary care where paramedics offeredclients early access to defibrillation and drug administration. Since these times Coronary Care Units, or Cardiac Care Units as they havebeen subsequently been termed, have developed into centres of research, clinical trials, advanced reperfusion and infarct limitation.Despite an international approach to cardiology as a specialty area of care and public health promotion campaigns, both national andinternationally, ACS still remains one of the most common causes of acute medical admissions to the ED and the leading single cause ofdeath.Web readingThe National Heart Foundation in association with The Cardiac Society of Australia and New Zealand has developed evidence basedacute coronary syndromes. An addendum to these guidelines has been published by the National Heart Foundation of Australia and th2011 and updated in 2016.Yancy, C.W., Jessup, M., Bozkurt, B., Butler, J., Casey, D.E., Colvin, M.M., Drazner, M.H., Filippatos, G., Fonarow, G.C., Givertz, M.M.ACC/AHA/HFSA focused update on new pharmacological therapy for heart failure: an update of the 2013 ACCF/AHA guideline for thereport of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart FaAmerica. Circulation, 134(13), pp.e282-e293.This may be accessed at: http://circ.ahajournals.org/content/134/13/e282 or through the Heart Foundation GuidelinesFigure: Algorithm for incorporating a high sensitivity troponin into the work-up of patients with suspected acute coronarysyndromes (ACS).From: (2011) 2011 addendum to the National Heart Foundation of Australia/Cardiac Society of Australia and New Zealand guidelines forthe management of acute coronary syndromes (ACS) 2006. Heart, Lung and Circulation, 20(8), p 491.4/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 15/214/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 16/214/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 17/21Care priorities: minimising damaged tissueThe patient with an acute coronary syndrome has impairment to coronary blood flow, most commonly from a ruptured plaque andsubsequent thrombus formation. The extent of damage to the myocardium depends upon the extent to which this thrombus affects bloodflow, the time that the myocardium has been ischaemic, the level of myocardial oxygen demand and the presence or lack of adequatecollateral circulation.Damage progresses from the centre of the ischaemic zone out in a ‘wave’ firstly involving the subendocardium and eventually to thesubepicardium. A patient left untreated can progress from a NSTEMI to a STEMI if left untreated. The major aim of management is tominimise the size of the ischaemic area by restoring blood flow to the affected area of cardiac muscle as quickly as possible. This can beachieved with various management strategies, drug therapies or surgery.ActivityBelow is a list of activities required to manage the patient who has just presented with chest pain. Analyse eachactivity and describe in detail how and why you would implement the care required for each. Sort this list in orderof clinical priority. Remember your DRABCDEF priority principles; naturally some of these tasks will be doneconcurrently.Give oxygen if neededEvaluate chest painObtain vital signsObtain an ECGRelieve the patient’s painPrevent further painProvide emotional supportObtain venous accessAdminister nitrates and aspirin.4/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 18/21Reperfusion strategiesFollowing an ST elevation MI reperfusion is a high priority in order to minimise damage to the myocardium. The process of the area ofnecrosis from the subendocardium to the subepicardium is called the evolution of the MI (Huszar 2014).This has been divided into four phases as illustrated by the following table.Table 5.1: Four phases of acute MI(Adapted from Huszar 2014, Basic dysrhythmias: interpretation & management, revised 4th edn.)The goal of treatment is to begin reperfusion therapy within the first 30-60 minutes of the onset of the infarction. This can take the form ofdrug therapy or coronary intervention. The major groups of medication agents are listed in the following table.Hemostasis: Lesson 6 – Anticoagulatio…4/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 19/21Table 5.2: (Adapted from Huszar 2014, Basic dysrhythmias: interpretation & management, revised 4th edn.)Reperfusion strategies by percutaneous transluminal coronary angioplasty (PTCA) involve the insertion of a balloon tipped catheter intothe occluded or narrowed vessel and inflation of the balloon to dilate the arterial lumen. Read the section in your text book on PTCA.Australian Resuscitation Council – ACS Reperfusion protocol – click here [scroll to the the bottom of the web page]Video Cardiac CatheterisationActivityOcclusion of the left anterior descending artery (LAD) causes which type of infarction? What are the potentialcomplications?Occlusion of the right coronary artery (RCA) causes which type of infarction? What are the potentialcomplications?What complications can occur as a result of coronary angioplasty? What are the possible treatmentstrategies for each?What are the long term management priorities for the patient recovering from and acute MI? Research theeducation and cardiac rehabilitation program offered by your hospital.Cardiac Cath with Angioplasty4/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 20/21Lifespan and Cultural ConsiderationsIndigenous AustraliansCardiovascular disease, particularly coronary heart disease, is the major cause of premature death for Aboriginal and Torres StraitIslander peoples, accounting for 26% of all deaths. Cardiovascular disease is also a major contributor to the gaps in life expectancybetween Indigenous and non-Indigenous Australians, with recent statistics suggesting that Australian Aboriginal and Torres Strait Islandermen and women can expect to live 10.6 and 9.5 fewer years, respectively, than other Australians.Acute coronary syndromes (ACS) include a broad spectrum of clinical presentations including ST-elevation myocardial infarction (STEMI),non-STEMI and an accelerated pattern of angina without evidence of myonecrosis (unstable angina); the latter two are often grouped asnon-ST-elevation acute coronary syndromes (NSTEACS). Current National Heart Foundation of Australia/Cardiac Society of Australia andNew Zealand guidelines highlight the importance of effective systems of care in delivering optimal management of ACS.In 2006, the Australian Institute of Health and Welfare (AIHW) released a landmark report on access to ACS treatment by Aboriginal andTorres Strait Islander patients. The report found that, compared with other Australians, Indigenous Australians hospitalised with ACS had:more than twice the rate of death from CHDa 40% lower rate of being investigated by angiographya 40% lower rate of percutaneous coronary intervention (PCI)a 20% lower rate of coronary artery bypass graft (CABG) surgery.As highlighted in the 2006 AIHW and subsequent reports, the inhospital disparities in ACS care experienced by Aboriginal and TorresStrait Islander peoples warrant special consideration by health service providers.ReferencesAustralian Bureau of Statistics. Life tables for Aboriginal and Torres Strait Islander Australians, 2010-2012. Canberra: ABS, 2013. (ABSCat. No. 3302.0.55.003.Australian Institute of Health and Welfare. The health and welfare of Australia’s Aboriginal and Torres Strait Islander people: an overview,Canberra: AIHW, 2011. (AIHW Cat. No. IHW 42.)Paediatric FocusKawasaki disease (KD) is the commonest cause of acquired heart disease in children in developed countries. The typical age atpresentation is 6 months to 5 years of age and the highest incidence of Kawasaki disease is in Asian countries. An infectious etiology islikely, but a specific agent has not yet been identified. The immune system is extensively involved in disease pathogenesis. KD isassociated with systemic vasculitis particularly affecting the coronary arteries, causing coronary artery aneurysms. KD is also potentiallyan important cause of long-term cardiac disease in adult life.The main sites of clinically important vascular involvement are the coronaryarteries, although other vessels such as the axillary arteries can be involved. CAA occur in 15–25% of untreated cases, with additionalcardiac features in a significant proportion of these including pericardial effusion, electrocardiographic abnormalities, pericarditis,myocarditis, valvular incompetence, cardiac failure and myocardial infarction.Reference:Dietz, S.M., Tacke, C.E., Hutten, B.A. and Kuijpers, T.W., 2015. Peripheral endothelial (dys) function, arterial stiffness and carotid intimamediathickness in patients after Kawasaki Disease: A systematic review and meta-analyses. PloS one, 10(7), p.e0130913.Older AdultAdvancing age is a risk factor for the development of coronary artery disease and is an important indicator of outcome after acutecoronary syndrome. Guidelines for the management of older adults are the same as for their younger counterparts, with the proviso thattreatments should be personalised. This includes an appreciation of functional status, co-morbidities, ischaemic and bleeding risk as wellas the physiological changes associated with ageing such as impaired renal function. In older adults, the diagnosis of ACS is oftenchallenging. ACS risk scores often classify older adults as high risk, this favours an early interventional strategy with prescription ofappropriate secondary prevention medications. Older adults commonly present with autonomic symptoms including dyspnoea (49.3%),diaphoresis (26.2%), nausea and vomiting (24.3%), but also with pre-syncope and syncope (19.1%). Chest pain is present in ∼40% ofthose over 85 compared with nearly 80% in those under 65. Consequently, there is a reduced probability of ACS being diagnosed and anincreased incidence of acute decompensation and in-hospital mortality.Delays to the provision and reporting of the initial ECG may delay diagnosis. Notably, more than two in five of ACS patients over 85 yearsof age do not have diagnostic ECG changes compared with a quarter of those under the age of 65 years. These factors may cloud theclinical picture and prevent timely diagnosis of ACS.In the case of STEMI, the myocardial infarction may be more evolved, with greater loss of myocardium and an increase in acutecomplications.The clinical presentation of ACS is often atypical in older patients and the initial ECG is often less commonly diagnostic in the older ACSpatient; thus greater reliance is placed on the cardiac troponin assay for making the diagnosis. However, elevated troponin levels mayoccur incidentally in the absence of ACS or conditions such as myocarditis, pulmonary embolism or sepsis.Reference:4/9/2020 Study plan: Week 5 – Acute coronary syndromeshttps://flo.flinders.edu.au/mod/book/tool/print/index.php?id=2585803 21/21Veerasamy, M., Edwards, R., Ford, G., Kirkwood, T., Newton, J., Jones, D. and Kunadian, V., 2015. Acute coronary syndrome amongolder patients: A review. Cardiology in review, 23(1), pp.26-32.The post Week 5 – Acute coronary syndromes appeared first on My Assignment Online.