Critical Thinking Exercise Acute Coronary Syndrome
A 58-year-old male comes to emergency services with a two-day history of severe chest pain. He came in today because the pain is severe and no longer relieved by resting. He has a significant history of father passing at age 62 from a heart attack, he smokes one pack of cigarettes per day and he describes his lifestyle as sedentary. He is diaphoretic with an elevated blood pressure of 180/96. His electrocardiogram and his cardiac lab tests are pending.
Acute Coronary Syndrome
Coronary plaque formation is usually a gradual process, and symptoms develop slowly over time. However, when a thrombus forms rapidly and obstructs the blood flow to one or more coronary arteries, acute coronary syndrome can occur, and it can cause sudden death (McCance & Huether, 2014). Acute coronary syndrome develops into a myocardial infarction when cardiac muscle ischemia is prolonged long enough that irreversible cardiac muscle damage occurs (McCance & Huether, 2014).
Anticipated Cardiac Markers and Electrocardiogram Results
All patients with chest pain combined with the history as presented in this case study should have a12-lead electrocardiogram (ECG). Clinicians should be aware that one initial ECG often does not offer enough information and multiple ECGs may be needed to make a definitive diagnosis. In these cases, the ECGs should be repeated every 30 to 45 minutes (Reeder & Simon, 2018). The initial ECG result was found to be non-definitive in 45% of patients and normal in 20% of patients who subsequently had a myocardial infarction (Reeder & Simon, 2018). There are two different ECG irregularities that are associated with acute myocardial ischemia, findings with a new ST wave elevation and findings with a new ST wave depression (Reeder & Simon, 2018).
Cardiac markers include various cardiac enzymes including labs such as serum troponin and creatine kinase levels. In general, these markers will rise with cardiac stress or acute cardiac ischemia (Reeder & Simon, 2018). Cardiac troponin I is the most reliable cardiac marker, and it can be detected within 2 to 4 hours after the patient experiences symptoms (McCance & Huether, 2014). Troponin levels can also be used to estimate the size of infarct and are usually taken at the onset of symptoms, six to nine hours later, and again at twelve to twenty-four hours and longer when needed (McCance & Huether, 2014).
Infarcted Myocardium Healing Process and Vulnerable Moments During Recovery
An acute myocardial infarction requires admission to the hospital with oxygen and anticoagulation medication given and constant monitoring of cardiac rhythm and cardiac biomarkers. Watching for any changes is imperative as in the first 24 hours post myocardial infarction, the patient is most vulnerable and at the highest risk for sudden death (McCance & Huether, 2014). Following a myocardial infarction, patients are at risk for several complications during the healing process. The patient’s risk is individualized and is dependent on the size and location of the infarct (LeWinter, 2018). Three significant pericardial complications that can occur post-MI are pericarditis, pericardial effusion and post-cardiac injury syndrome (LeWinter, 2018). Pericarditis occurs after the MI, and usually, a rub can be heard via auscultation initially with 85% resolving within three days post-MI (LeWinter, 2018). During this three-day window, the patient is vulnerable as pericarditis can cause increased chest pain and increased respiratory effort (McCance ; Huether, 2014). Pericardial effusion is the buildup of fluid in the pericardial cavity and can increase the pressure around the heart to the point of cardiac tamponade which can drastically reduce cardiac output (McCance ; Huether, 2014). Patients with post-cardiac injury syndrome present with symptoms similar to acute pericarditis but usually this occurs weeks to months post MI (LeWinter, 2018). Post-cardiac injury syndrome is an inflammatory response where the pericardium, pleura, and lungs have immune complexes deposited in them and although most have a good prognosis, ten to fifteen percent of patients can have significant complications (LeWinter, 2018).
It’s important to note that patients presenting with signs, symptoms, and history of acute coronary syndrome are treated as emergencies. The initial phase of treatment is rapid evaluation and immediate diagnosis (Reeder & Simon, 2018). The medical treatment starts immediately as the initial ECG is often not informative and the cardiac markers take a minimum of two hours to become detectable. Airway and breathing are assessed, ECG leads are attached, IV access is obtained, aspirin and nitrates are given right away until acute coronary syndrome can be ruled out (Reeder & Simon, 2018). Although the size and location of the infarct directly affect the prognosis, rapid triage and evaluation is initially the goal of medical treatment.