The ACC has issued guidance for the diagnosis and management of acute myocarditis in adult patients, delivering a streamlined decision-making framework that reflects recent advancements in clinical practice. The 2024 ACC Expert Consensus Decision Pathway (ECDP) on Strategies and Criteria for the Diagnosis and Management of Myocarditis, published in JACC, includes a 5-step care pathway, as well as recommendations for returning to strenuous physical activity and opportunities to close knowledge gaps and address future research needs.  

The 5-step pathway begins with diagnosis. Recognizing that patients with myocarditis can present with diverse signs, the ECDP focuses on three classic presentations: chest pain, symptoms related to arrhythmia such as palpitations or syncope, or symptoms of heart failure (HF)/cardiogenic shock.

“The initial step for a clinician is to recognize the condition by being aware of its three classic presentations as outlined in the ECDP,” said Mark H. Drazner, MD, MSc, FACC, writing committee chair. “Once a patient is diagnosed, clinicians can then follow the next 4 steps in the care pathway, including triaging the patient, obtaining pivotal diagnostic tests, providing appropriate therapies, and then longitudinal follow-up.”

Other highlights from the document include a recommendation for genetic counseling and testing for all consenting patients given the increasing recognition of genetic predisposition to myocarditis. Use of high-sensitivity cardiac troponin, as well as cardiac magnetic resonance imaging and endomyocardial biopsy, are also addressed. Additionally, the document focuses on the need for ongoing patient monitoring and follow-up and stresses the important role risk stratification plays in guiding decisions on whether or when patients with symptomatic myocarditis should be referred to an advanced HF center. “There should be a low threshold to transfer patients with high-risk features,” the authors say.

Looking ahead, the ECDP recommends several areas where further research is needed, including “how social determinants of health impact the development and progression of myocarditis;” the benefits of immunosuppression in lymphocytic myocarditis; and “whether unloading of the left ventricle for those on extracorporeal membrane oxygenation improves outcomes.” The document also underscores the need to look at the use of international registries, improved phenotyping by novel biomarkers, and the psychological impacts on patients and caregivers.”

Clinical Topics: Arrhythmias and Clinical EP, Heart Failure and Cardiomyopathies, Noninvasive Imaging, Implantable Devices, SCD/Ventricular Arrhythmias, Atrial Fibrillation/Supraventricular Arrhythmias, Acute Heart Failure, Magnetic Resonance Imaging

Keywords: Arrhythmias, Cardiac, Heart Failure, Magnetic Resonance Imaging, Myocarditis