Risks versus Benefits of NSAIDs Including Aspirin in Myocarditis

Prostaglandin E2 and myocarditis; friend or foe?

This review article summarizes the role of prostaglandin E2 (PGE2) and its receptors (EP1-EP4) as it relates to the inflammatory cardiomyopathy, myocarditis. During the COVID-19 pandemic, the onset of myocarditis in a subset of patients prompted a debate on the use of nonsteroidal anti-inflammatory drugs (NSAIDs), like ibuprofen, which act to inhibit the actions of prostaglandins. This review aims to further understanding of the role of PGE2 in the pathogenesis or protection of the myocardium in myocarditis. Inflammatory cardiomyopathies encompass a broad spectrum of disorders, all characterized by cardiac inflammation. Therefore, for the purpose of this review, the authors have placed particular emphasis on etiologies of myocarditis where effects of PGE2 have been documented.

Multimodality imaging in acute myocarditis

The diagnosis of acute myocarditis often involves several noninvasive techniques that can provide information regarding volumes, ejection fraction, and tissue characterization. In particular, echocardiography is extremely helpful for the evaluation of biventricular volumes, strain and ejection fraction. Cardiac magnetic resonance, beyond biventricular volumes, strain, and ejection fraction allows to characterize myocardial tissue providing information regarding edema, hyperemia, and fibrosis. Contemporary cardiac computed tomography angiography (CCTA) can not only be extremely important for the assessment of coronary arteries, pulmonary arteries and aorta but also tissue characterization using CCTA can be an additional tool that can explain chest pain with a diagnosis of myocarditis.

Treatment with Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) Does Not Affect Outcome in Patients with Acute Myocarditis or Myopericarditis

Background: Previous animal studies reported an association of non-steroidal anti-inflammatory drugs (NSAIDs) with adverse outcomes in acute myocarditis, which is why these drugs are currently not recommended in affected patients. In this retrospective case-control study, we sought to investigate the effects of NSAID treatment in patients with acute myocarditis and myopericarditis to complement the available evidence. Method: A total of 114 patients with acute myocarditis were retrospectively enrolled. Demographical, clinical and laboratory data were extracted from hospital records. Patients who received NSAIDs (n = 39, 34.2%) were compared to controls. Follow-up on all-cause mortality was acquired for two years. Propensity score matching was additionally conducted to account for covariate imbalances between groups. Results: Treatment with NSAIDs was neither associated with a worse outcome (p = 0.115) nor with significant differences in left ventricular systolic function (p = 0.228) or in-hospital complications (p = 0.507). Conclusion: Treatment with NSAIDs was not associated with adverse outcomes in our study cohort. Together with the findings of previous studies, our results indicate that these drugs could be safely administered in patients with myocarditis and myopericarditis.

Clinically Suspected Myocarditis Temporally Related to COVID-19 Vaccination in Adolescents and Young Adults

BACKGROUND

Understanding the clinical course and short-term outcomes of suspected myocarditis following COVID-19 vaccination has important public health implications in the decision to vaccinate youth.

METHODS

We retrospectively collected data on patients <21 years-old presenting before 7/4/2021 with suspected myocarditis within 30 days of COVID-19 vaccination. Lake Louise criteria were used for cardiac magnetic resonance imaging (cMRI) findings. Myocarditis cases were classified as confirmed or probable based on the Centers for Disease Control and Prevention definitions.

RESULTS

We report on 139 adolescents and young adults with 140 episodes of suspected myocarditis (49 confirmed, 91 probable) at 26 centers. Most patients were male (N=126, 90.6%) and White (N=92, 66.2%); 29 (20.9%) were Hispanic; and median age was 15.8 years (range 12.1-20.3, IQR 14.5-17.0). Suspected myocarditis occurred in 136 patients (97.8%) following mRNA vaccine, with 131 (94.2%) following the Pfizer-BioNTech vaccine; 128 (91.4%) occurred after the 2nd dose. Symptoms started a median of 2 days (range 0-22, IQR 1-3) after vaccination. The most common symptom was chest pain (99.3%). Patients were treated with nonsteroidal anti-inflammatory drugs (81.3%), intravenous immunoglobulin (21.6%), glucocorticoids (21.6%), colchicine (7.9%) or no anti-inflammatory therapies (8.6%). Twenty-six patients (18.7%) were in the ICU, two were treated with inotropic/vasoactive support, and none required ECMO or died. Median hospital stay was 2 days (range 0-10, IQR 2-3). All patients had elevated troponin I (N=111, 8.12 ng/mL, IQR 3.50-15.90) or T (N=28, 0.61 ng/mL, IQR 0.25-1.30); 69.8% had abnormal electrocardiograms and/or arrythmias (7 with non-sustained ventricular tachycardia); and 18.7% had left ventricular ejection fraction (LVEF) <55% on echocardiogram. Of 97 patients who underwent cMRI at median 5 days (range 0-88, IQR 3-17) from symptom onset, 75 (77.3%) had abnormal findings: 74 (76.3%) had late gadolinium enhancement, 54 (55.7%) had myocardial edema, and 49 (50.5%) met Lake Louise criteria. Among 26 patients with LVEF <55% on echocardiogram, all with follow-up had normalized function (N=25).

CONCLUSIONS

Most cases of suspected COVID-19 vaccine myocarditis occurring in persons <21 years have a mild clinical course with rapid resolution of symptoms. Abnormal findings on cMRI were frequent. Future studies should evaluate risk factors, mechanisms, and long-term outcomes.

[Myocarditis]

Acute myocarditis must be considered in patients with recent onset of cardiac failure or arrhythmia. Fulminant myocarditis is a distinct entity characterized by sudden onset of severe congestive heart failure or cardiogenic shock, usually following a flu-like illness, parvovirus B19, human herpesvirus 6, coxsackie virus and adenovirus being the most frequently viruses responsible for the disease. In this setting, early recognition of patients rapidly progressing to refractory cardiac failure and their immediate transfer to a medical-surgical center experienced in mechanical circulatory support is warranted. Treatment of acute myocarditis relies on conventional heart failure therapy. Immunosuppression of autoreactive myocarditis or immuno-stimulants such as interferons for chronic viral myocarditis could be of interest but their potential therapeutic role requires further investigation.

Prognosis of myopericarditis as determined from previously published reports

BACKGROUND

The prognosis of pericarditis with concomitant myocarditis, especially in the setting of troponin elevation, is a reason for concern because it could imply an adverse outcome.

METHODS

We performed a comprehensive Medline search of all publications from 2000 to 2013 with the MeSH terms 'pericarditis', 'myocarditis' and 'prognosis'. Additional publications were sought using the reference lists of identified papers, the published reviews on this topic, and a search of abstracts from the American Heart Association, American College of Cardiology, and European Society of Cardiology scientific sessions.

RESULTS

We identified eight major clinical series evaluating the prognosis of myopericarditis. Studies included a total of 389 patients with myopericarditis (mean age 31.7 years, men-to-women ratio 4.0). After a mean follow-up of 31 months, residual left-ventricular dysfunction was reported in 3.5% without cases of heart failure. Recurrences occurred in 13.0% of cases mainly as recurrent pericarditis (>90%), cardiac tamponade and constrictive pericarditis in less than 1% of cases. The overall prognosis seems good (no mortality), with only one single discordant study reporting three deaths: one related to cardiac tamponade and two sudden cardiac deaths during hospitalization, but no out-of-hospital deaths during follow-up.

CONCLUSION

Myopericarditis has a good overall prognosis. Troponin elevation in this setting does not predict an adverse outcome in most cases. Thus it is important to reassure the patients on their prognosis, explaining the nature of the disease and the likely course. Diagnostic and therapeutic choices should take into account the overall good outcome of these patients, including less invasive diagnostic tools and toxic drugs.

Thrombotic events in critically ill children with myocarditis

BACKGROUND

Children with myocarditis have multiple risk factors for thrombotic events, yet the role of antithrombotic therapy is unclear in this population. We hypothesised that thrombotic events in critically ill children with myocarditis are common and that children with myocarditis are at higher risk for thrombotic events than children with non-inflammatory dilated cardiomyopathy.

METHODS

This is a retrospective chart review of all children presenting to a single centre cardiac intensive care unit with myocarditis from 1995 to 2008. A comparison group of children with dilated cardiomyopathy was also examined. Antithrombotic regimens were recorded. The primary outcome of thrombotic events included intracardiac clots and any thromboembolic events.

RESULTS

Out of 45 cases with myocarditis, 40% were biopsy-proven, 24% viral polymerase chain reaction-supported, and 36% diagnosed based on high clinical suspicion. There were two (4.4%) thrombotic events in the myocarditis group and three (6.7%) in the dilated cardiomyopathy group (p = 1.0). Neither the use of any antiplatelet or anticoagulation therapy, use of intravenous immune globulin, presence of any arrhythmia, nor need for mechanical circulatory support were predictive of thrombotic events in the myocarditis, dilated cardiomyopathy, or combined groups.

CONCLUSIONS

Thrombotic events in critically ill children with myocarditis and dilated cardiomyopathy occurred in 6% of the combined cohort. There was no difference in thrombotic events between inflammatory and non-inflammatory cardiomyopathy groups, suggesting that the decision to use antithrombotic prophylaxis should be based on factors other than the underlying aetiology of a child's acute decompensated heart failure.

Coagulation, protease-activated receptors, and viral myocarditis

The coagulation protease cascade plays an essential role in hemostasis. In addition, a clot contributes to host defense by limiting the spread of pathogens. Coagulation proteases induce intracellular signaling by cleavage of cell surface receptors called protease-activated receptors (PARs). These receptors allow cells to sense changes in the extracellular environment, such as infection. Viruses activate the coagulation cascade by inducing tissue factor expression and by disrupting the endothelium. Virus infection of the heart can cause myocarditis, cardiac remodeling, and heart failure. A recent study using a mouse model have shown that tissue factor, thrombin, and PAR-1 signaling all positively regulate the innate immune during viral myocarditis. In contrast, PAR-2 signaling was found to inhibit interferon-β expression and the innate immune response. These observations suggest that anticoagulants may impair the innate immune response to viral infection and that inhibition of PAR-2 may be a new strategy to reduce viral myocarditis.

[Acute myocarditis]

Myocarditis is defined as inflammation of the myocardium accompanied by myocellular necrosis. Acute myocarditis must be considered in patients who present with recent-onset of cardiac failure or arrhythmia. Fulminant myocarditis is a distinct entity characterized by sudden onset of severe congestive heart failure or cardiogenic shock, usually following a flu-like illness, parvovirus B19, human herpesvirus 6, coxsackievirus and adenovirus being the most frequently viruses responsible for the disease. Treatment of myocarditis remains largely supportive, since immunosuppression has not been proven to be beneficial for acute lymphocytic myocarditis. Trials of antiviral therapies, or immunostimulants such as interferons, suggest a potential therapeutic role but require further investigation. Lastly, early recognition of patients rapidly progressing to refractory cardiac failure and their immediate transfer to a medical-surgical center experienced in mechanical circulatory support is warranted. In this setting, ECMO should be the first-line mechanical assistance. For highly unstable patients, a Mobile Cardiac Assistance Unit, that rapidly travels to primary care hospitals with a portable ECMO system and hooks it up before refractory multiorgan failure takes hold, is the preferred option.

Viral causes of human myocarditis

The diagnosis of acute myocarditis is complex and challenging. The use of the Dallas criteria in the diagnosis of myocarditis is associated with poor sensitivity and specificity because of the sampling error related to the often focal distribution of the specific histological lesions in cardiac tissue and the variability in pathological interpretation. To improve histological diagnosis, additional virological evaluation of cardiac tissues is required, with immunohistochemical and polymerase chain reaction (PCR) techniques allowing identification and quantification of viral infection markers. The diagnostic gold standard is endomyocardial biopsy (EMB) with the histological Dallas criteria, in association with new immunohistochemical and PCR analyses of cardiac tissues. Using real-time PCR and reverse transcription PCR assays, parvovirus B19, Coxsackie B virus, human herpesvirus 6 (HHV-6) type B and adenovirus have been detected in 37, 33, 11 and 8% of EMB, respectively, from young adults (aged<35 years) with histologically proven acute myocarditis. Viral co-infections have also been found in 12% of acute myocarditis cases, generally parvovirus B19 plus HHV-6. Moreover, herpesviruses such as the Epstein-Barr virus or cytomegalovirus can also be associated with myocarditis after heart transplantation. During the clinical course of myocarditis, the immunohistochemical detection of enterovirus, adenovirus or parvovirus B19 capsid proteins or herpesvirus late proteins is necessary to differentiate a viral cardiac infection with replication activities from a persistent or latent cardiac infection. These new viral diagnostic approaches can lead to better identification of the aetiology of myocarditis and may therefore enable the development and evaluation of specific aetiology-directed treatment strategies.

[Acute coronary syndrome after diclofenac induced coronary spasm]

We report about a 67-year old man, who was submitted to our clinic with acute coronary syndrome. The cardiac catheterization showed a proximal thrombus in the left anterior descending (LAD). The other coronary arteries did not have significant lesions. After percutaneous transluminal coronary angioplasty with stent-implantation into the proximal LAD the patient remained clinically stable. Cardiac enzymes confirmed no myocardial necrosis. Three days after the acute coronary syndrome the patient developed a podagra, which was treated with colchicinum, diclofenac and local cooling. Five hours after initial therapy the patient developed severe symptoms of angina pectoris and electrocardiographical signs of an acute posterior and anterior myocardial infarction. Immediate coronary angiography demonstrated extended vasospasm of the right coronary artery. Intracoronary application of verapamil and nitroglycerin resolved the coronary spasm. The patient reported about a self-indicated application of diclofenac six hours before hospital admission. This case demonstrates that oral application of diclofenac can provoke coronary vasospasm.