Introduction to Acute Coronary Syndrome

Acute Coronary Syndrome is a very serious condition that can be life-threatening and require immediate treatment to save as much heart tissue as possible. ACS is a type of Coronary Heart Disease (CHD) that affects over 15 million Americans and is responsible for a third of total deaths in individuals over thirty-five years of age.

Acute Coronary Syndrome Causes

An unhealthy lifestyle (or a variety of other factors) can result in high levels of cholesterol in the body. This cholesterol can build up in blood vessels over time to form plaques. When one of these plaques eventually ruptures, a thrombus (or blood clot) can form which becomes lodged in the vessel and blocks sufficient blood flow through the area, starving the heart of oxygen.

If severe enough, this lack of oxygen can result in cell death in the heart tissue, a myocardial infarction, also called a heart attack. When this blockage does not result in cell death, it is referred to as unstable angina. Even without cell death, heart cells may still become damaged, and their function may become temporarily or permanently impaired.

Though not directly caused by ACS, many factors can drastically increase the risk of heart events such as Acute Coronary Syndrome. Here are a few examples.

Age

As a person ages their blood vessels naturally become harder and less flexible, increasing their risk for heart disease.

Hypertension

Chronic high blood pressure puts constant strain on blood vessels and certain organs, including the heart. Over time this stress can weaken the heart and place it at higher risk for disease.

Hypercholesterolemia

A high level of cholesterol is a direct risk factor for heart disease. If untreated, this cholesterol can form dangerous plaques in blood vessels.

Smoking

Smoking, particularly cigarette smoking, drastically increases the risk for cardiac events through a number of ways. When done on a regular basis, smoking reduces oxygen levels in the blood, promotes blood clot formation, reduces levels of HDL “good cholesterol” in the blood, and can even trigger spasms and irregular heartbeats.

Sedentary Lifestyle

Participating in a sedentary lifestyle makes necessary blood circulation more difficult and denies the heart of the exercise it needs to remain strong and healthy.

Diabetes

Similar to hypertension, diabetes places a large amount of stress on the heart which may cause it to become more susceptible to disease.

Diet

An unhealthy diet can lead to a range of factors that greatly increase the risk of heart disease. Fat stores will increase in the body over time and cholesterol levels will rise as a result of a consistently unhealthy diet.

Obesity

Often a result of lack of exercise and/or an unhealthy diet, obese individuals tend to have much higher levels of cholesterol, higher blood pressure, increased risk for diabetes, and so on.

Family History

Unfortunately, genetics can also play a role in the likelihood of developing heart disease. Those with a strong family history of ACS are more likely to develop this condition.

Acute Coronary Syndrome Symptoms

The symptoms of Acute Coronary Syndrome typically begin quite rapidly, and since this condition can be so dangerous, it’s essential to be able to recognize the early signs and symptoms of a heart event. The most common signs and symptoms of ACS are as follows:

• Chest pain is typically described as throbbing, tightness, or burning
• Pain spreading from the chest up to the upper torso including the shoulders, arms, back, neck, and/or jaw
• Nausea
• Indigestion
• Difficulty breathing
• Sweating
• Dizziness
• Fatigue
• Restlessness

If any of these symptoms are experienced or you have any other reason to believe you may be experiencing a coronary event, call 911 immediately.

Acute Coronary Syndrome Pathophysiology

In addition to the above-mentioned signs and symptoms, Acute Coronary Syndrome can also result in several other clinical manifestations which can be useful for confirming and diagnosing this condition.

Creatine Kinase (CK)

Creatine Kinase is an enzyme commonly found within muscle tissue cells and is released into the bloodstream when cell damage occurs. Because CK levels can rise for several reasons other than cardiac injury, this test is not conclusive, though it can be useful to provide diagnostic hints and determine if additional testing is necessary.

Creatine Kinase-MB Isoenzyme

The MB isoenzyme of creatine is significantly more cardio-specific than CK, and is often measured quickly upon admission. While this test can help determine if a cardiac event occurs, it does not provide evidence for how large of an event occurred.

Cardiac Troponins

Troponins are another substance found within muscle cells with some forms being specific to cardiac muscle. Similar to creatine kinase, troponins are released into the bloodstream when muscle damage occurs, though these markers are more cardiac-specific than CK making them the preferred cardiac serum markers to test for heart damage.

Myoglobin

Another serum biomarker, myoglobin has low cardiac specificity but very high sensitivity. This means that if myoglobin levels are normal, no cardiac damage is likely to have occurred. This marker is used in conjunction with the others for diagnostic purposes.

Electrocardiogram (ECG)

Perhaps the most definitive diagnostic test, an ECG is a test where electrodes are attached to the skin to measure the activity of the heart to determine if it is operating correctly.

Acute Coronary Syndrome Treatment

Acute Coronary Syndrome Pharmacology

Initially, treatment of ACS should be focused on restoring blood flow to the heart as quickly and effectively as possible to minimize damage. Additionally, symptoms such as chest pain should also be addressed. Long-term treatment goals should be targeted toward maintaining proper heart function and lowering the risk of a similar occurrence happening again.  The following are types of medications that may be used for ACS:

Thrombolytic Drugs

This type of medication may be useful in the early stages of ACS treatment as they are used to help break up blood clots that may be the cause of the event. Examples of thrombolytic drugs are reteplase, anistreplase, tenecteplase, and streptokinase.

Antiplatelet Drugs

Antiplatelet drugs are commonly used to reduce the risk of blood clot formation, often for a predetermined amount of time after a cardiac event. Examples of antiplatelet drugs include aspirin, clopidogrel, and prasugrel.

Nitroglycerin

Nitroglycerin is commonly prescribed to clients with a history or high risk of heart events. It is intended to be used in emergency situations to help maintain blood flow to the heart until further treatment can be received. Nitroglycerin is typically dissolved under the tongue and works by rapidly dilating blood vessels, allowing blood the room to flow past a blockage.

Beta-Blockers

This class of medication provides several benefits by reducing blood pressure and slowing the heart. Both of these actions are useful for reducing strain on the heart, and some beta-blockers have been shown to improve the mortality rate of heart disease clients. Examples include carvedilol, metoprolol succinate, and bisoprolol.

Angiotensin Converting Enzyme Inhibitors (ACE-Inhibitors)

ACE Inhibitors can also provide significant benefits to clients with ACS as a mainstay for the treatment of hypertension. ACE Inhibitors help to protect the heart by reducing blood pressure, and also provide protective benefits to the kidneys as well. Examples include lisinopril and enalapril.

Angiotensin Receptor Blockers (ARBs)

Similar to ACE-Inhibitors, ARBs are typically used to lower blood pressure and provide some mortality benefit. ARBs are never used in conjunction with ACE-Inhibitors, a client is placed on either one or the other at any given time. Examples include losartan, candesartasn, and valsartan.

Statins

When it comes to providing mortality benefits, statins are difficult to top. These medications have been shown to greatly reduce levels of harmful LDL cholesterol, drastically lowering the chance of further plaque formation. Examples of statins include atorvastatin, simvastatin, and rosuvastatin.

Stents

One non-drug treatment for ACS is the placement of a stent. Stents can be carefully inserted into the blocked artery and are used to compress the plaque buildup against the vessel wall to restore blood flow. Many stents are left within the artery to hold the passageway open.

Coronary Bypass Surgery

In some instances, the blockage may not be able to be removed. Coronary Bypass Surgery offers an alternative solution. In this surgical procedure an artery (usually harvested from the leg) is grafted around the heart to circumvent the blockage.

Acute Coronary Syndrome Nursing Interventions

As with most critical conditions, nurses play a large part in the treatment of Acute Coronary Syndrome. In addition to the initial treatment and administration of medications, the role nurses play in the lifestyle recommendations of their clients should not be overlooked. Here are a few examples that nursing staff may provide education on to reduce the risk of future cardiac events:

Medication Adherence

While traditionally the job of a pharmacist or physician, clients can never be reminded too much of the importance to remain adherent to their medications. After a coronary event, many of the newly prescribed medications are intended to be taken or a significant amount of time, and possibly even for the rest of the client’s life.

DASH Diet

Making positive changes to diet is one of the best ways to lower the risk of heart disease. The DASH diet, which stands for Dietary Approaches to Stop Hypertension, provides a helpful framework for these changes. In addition to practicing healthy portion control, the DASH diet also recommends lowered sodium intake, more consumption of vegetables and lean meat, higher fiber intake, and consumption of whole grains. When practiced consistently, these dietary changes will help individuals to lose weight, lower cholesterol, and reduce blood pressure.

Regular Physical Exercise

Another counseling point that nurses should stress is the importance of participating in regular physical exercise. Not only does exercise help to lower blood pressure and cholesterol levels, but it also strengthens the heart and lowers fat reserves.

Smoking Cessation

Last but certainly not least, any client who has a history of smoking should be greatly encouraged to stop this harmful habit. Clients should be educated on the harms of smoking, as well as the slew of benefits that come from quitting. It should be reinforced that there are a variety of strategies, counseling types, and medications to help with smoking cessation.

Conclusion of Acute Coronary Syndrome

Acute Coronary Syndrome is a type of heart disease that encompasses three main types of similar conditions; ST-Elevated Myocardial Infarction (STEMI), Non ST-Elevated Myocardial Infarction (NSTEMI), and unstable angina. Because heart disease affects millions of people within the US and accounts for such a staggering number of deaths, this topic is especially important for nursing staff to become familiar with in order to provide the best care possible to their clients.

References

Acute coronary syndrome. American Heart Association. https://www.heart.org/en/health-topics/heart-attack/about-heart-attacks/acute-coronary-syndrome. Accessed May 26, 2020.

Acute coronary syndrome. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/acute-coronary-syndrome/symptoms-causes/syc-20352136. Accessed May 26, 2020.

Diagnosis of acute coronary syndrome. American Family Physician. https://www.aafp.org/afp/2005/0701/p119.html. Accessed May 26, 2020.

Acute coronary syndrome. NCBI. https://www.ncbi.nlm.nih.gov/books/NBK459157/. Accessed May 26, 2020.

Smoking and coronary artery disease. American College of Cardiology. https://www.cardiosmart.org/Healthwise/hw79/682/hw79682. Accessed May 26, 2020.

Nutrition and healthy eating. Mayo Clinic. https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/dash-diet/art-20048456. Accessed May 26, 2020.