Nursing Care and Pathophysiology of Myocarditis

 Hey everyone. This is Kristen from nursing.com, and we’re going to talk about myocarditis. Let’s talk briefly about the pathophysiology behind myocarditis. Myocarditis occurs when the myocardial heart muscle, or the myocardial tissue, that thick layer in the center of the layers of the heart, becomes inflamed. It can be caused by an acute infectious process or a systemic inflammatory condition such as an autoimmune disease. It can also be the result of toxins. It can be the result of environmental conditions or any other drugs or anything that’s in your system. In severe cases, the heart muscle will actually weaken to the point where it does reduce its pumping ability. Let’s look at the image here that we have on the slide. If you notice in the healthy heart, all of the walls are pretty consistent throughout, but if you take your point of view and you look over at the myocarditis side of the image, you notice that that middle layer is a little bit thicker. It’s a little bit more inflamed. And what this does is it causes a reduction in cardiac output. 

 Think about it this way. I have my hand here, right? And normally the heart pumps just like this, it’s pumping out blood to the systemic circulation, especially if it’s on the left side of the heart. Now, if I injured my hand, essentially what would happen is, it would become really swollen and inflamed. I couldn’t do this anymore. All I could do would be this. This is going to impact the amount of pumping ability that I have for my hand, let alone for the heart. So, think of it that way. All right. Remember, y’all, the linchpin that goes along with the myocarditis heart is that, say with me, myocarditis reduces the pumping ability of the heart due to inflammation. So now what does this do to your patient? Well, this will ultimately reduce cardiac output and therefore it will subsequently reduce body perfusion. 

 So how is your patient going to clinically present when they have myocarditis? Well, I can speak from experience. I had a patient that came in post COVID 19 infection, and some of the things that they were experiencing were kind of not specific, but they really did point to myocarditis. So the patient was presenting with chest pain that was not radiating. They did have shortness of breath. They had fatigue and they had what they felt like was fluttering in their chest or otherwise known as a general term of arrhythmias. Additionally, patients can present with signs and symptoms of infection if they’re actively infected; this can include fever, muscle aches, sore, throat, headache, and even diarrhea, depending on the causative agent. So diagnostically, there’s some things you want to for, and our patient who we are suspecting has myocarditis. 

 One of the first things we’re going to do is we’re going to look at the laboratory testing. And two particular tests that are really important to myocarditis are c-reactive protein and troponin, both of which are going to be elevated. These are going to be elevated because C-reactive protein is indicative of inflammation. And troponin is indicative of that being limited to the cardiac muscle tissue. An ECG is going to exclude any alternative causes of those cardiac symptoms that this patient may or may not be experiencing as well as going to evaluate it for any arrhythmias that are suggestive of the cause of myocarditis. It’s also going to indicate that this in fact is myocarditis. And so, in this particular image here, we see that we have nonspecific changes on the ECG. These nonspecific ST segment elevations that are happening throughout the entire, all of the leads, are indicative of a myocarditis rather than a patient who’s experiencing an acute coronary syndrome. 

 Lastly, radiologically, the size of the heart on the radiograph is going to end up either be normal, which it is in this image right here, or it’s going to be enlarged. And this is indicative of inflammation, as well as it could be indicative of some heart failure symptomatology that they may be experiencing. 

 So how do we manage our pain in patients with myocarditis? While there’s no curative treatment for myocarditis, this condition may actually self-resolve with time; we can help that along for the patient by giving them some pain medication that may help alleviate some of that symptomology they’re experiencing regarding chest pain. Additionally, if they are experiencing some symptoms that are associated with heart failure conditions, we can encourage lifestyle changes. This can include activity restrictions, or dietary restrictions such as your low sodium diet or your fluid restrictions. Additionally, some common medications that we typically use for these patients are related to symptom management. We may offer them angiotensin converting enzyme inhibitors, or ACE inhibitors or angiotensin receptor blockers, or ARBs. And this is going to help reduce the blood pressure as well as assist in any cardiac remodeling that may take place due to the condition. Beta blockers are also going to impact the arrhythmias that the patient may be experiencing, or as well as it’s also going to help with the cardiac remodeling. Diuretics are going to help reduce fluid if the patient is experiencing fluid retention. And corticosteroids are going to be used to assist with the systemic inflammation that the patient is experiencing; it will ultimately reduce that. 

 There are certain things you want to avoid in a patient who’s been diagnosed with myocarditis. One of the very first things is NSAID use. NSAID use is going to make any symptoms that are associated with heart failure even worse in a patient who has myocarditis. Therefore, the avoidance of their use completely is recommended. Additionally, alcohol consumption is going to worsen the condition of myocarditis and even worsen its severity. And lastly, exercise is only going to further exacerbate the clinical presentation symptoms that this has arrived with such as chest pain, shortness of breath and fatigue. 

 So, let’s recap the linchpins or the key points associated with myocarditis. Myocarditis is an inflammation of the myocardium. Clinically, your patient is going to present with chest pain, shortness of breath, they may have fatigue, and any signs of symptoms of infection that may be present if that’s the causative agent. We’re going to diagnostically test them using a c-reactive protein and a troponin, both of which are going to be elevated as well as we’re going to have potentially some nonspecific changes on your ECG, as well as the patient radiologically or via x-ray may or may not have an enlarged heart. Patient management-wise, this condition could be self resolving. We are going to go for treating the underlying cause if we happen to know what that is, aka an infection, as well as we’re also going to do symptom management. So if that patient is having blood pressure issues, we’re going to use your ACEI and ARB, if the patient’s having fluid issues, we’re going to use our diuretics, and we’re also going to try to give them some corticosteroids to help reduce that inflammation that’s present that’s affecting them. 

 So, remember, nursing school can be tough, but I want you guys to continue on your journey, so that you can reach your ultimate goal because you can do it and it is worth it. So, therefore, I want to leave you with a quote, and it says an expert in anything was once a beginner.

 Great job, you guys, this concludes our lesson on myocarditis. And now you can test your knowledge with a practice quiz. We love you guys now, go out and be your best self today, and, as always, happy nursing.

References:

Cooper, L. (July 13, 2021). Clinical manifestations and diagnosis of myocarditis. UpToDate. 

https://www.uptodate.com/contents/clinical-manifestations-and-diagnosis-of-myocarditis-in-adults?search=myocarditis&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1

Cooper, L. (June 17, 2020). Treatment and prognosis of myocarditis in adults. UpToDate. 

https://www.uptodate.com/contents/treatment-and-prognosis-of-myocarditis-in-adults?search=myocarditis&source=search_result&selectedTitle=2~150&usage_type=default&display_rank=2