From the Guidelines
Fulminant myocarditis in young adults presenting to the ER with respiratory distress should be recognized by a combination of clinical symptoms, laboratory tests, and imaging studies, with a high index of suspicion and prompt evaluation, as recommended by the 2022 ACC expert consensus decision pathway 1. To recognize fulminant myocarditis, look for symptoms including severe shortness of breath, chest pain, fatigue, palpitations, and syncope, often preceded by a viral prodrome with fever, upper respiratory symptoms, or gastrointestinal issues. Key diagnostic criteria for myocarditis include:
- Cardiac symptoms (eg, chest pain, dyspnea, palpitations, syncope)
- An elevated cTn
- Abnormal electrocardiographic, echocardiographic, CMR, and/or histopathologic findings on biopsy or postmortem evaluation in the absence of flow-limiting coronary artery disease, as defined by the 2022 ACC expert consensus decision pathway 1. Physical examination may reveal tachycardia, hypotension, elevated jugular venous pressure, and pulmonary crackles. The initial testing should consist of:
- An ECG, which may show diffuse ST-segment changes, conduction abnormalities, or arrhythmias
- Measurement of cTn (preferably using a high-sensitivity assay)
- An echocardiogram to assess ventricular function, which typically shows global hypokinesis and reduced ejection fraction, as recommended by the 2022 ACC expert consensus decision pathway 1. Once suspected, initiate supportive care with supplemental oxygen, consider non-invasive ventilation if needed, and start hemodynamic monitoring. Early cardiology consultation is essential, as these patients can deteriorate rapidly, potentially requiring mechanical circulatory support such as ECMO, and hospitalization is recommended for patients with definite myocarditis that is either mild or moderate in severity, ideally at an advanced heart failure center, as recommended by the 2022 ACC expert consensus decision pathway 1. The pathophysiology involves acute inflammation of the myocardium, often triggered by viral infection, leading to myocardial dysfunction, heart failure, and potentially cardiogenic shock. In patients with fulminant myocarditis, the short-term survival rate is only 58%, and refractory sustained arrhythmias are typical for the fulminant form of myocarditis, as reported in the 2015 ESC guidelines for the management of patients with ventricular arrhythmias and the prevention of sudden cardiac death 1. Therefore, it is crucial to recognize fulminant myocarditis early and provide prompt and appropriate treatment to improve outcomes and reduce morbidity and mortality.
From the Research
Recognition of Fulminant Myocarditis
Fulminant myocarditis is a rare and severe form of myocarditis that can present with respiratory distress in young adults. The key to recognizing fulminant myocarditis is to identify the signs and symptoms of severe cardiac inflammation and hemodynamic derangement.
- Sudden and severe diffuse cardiac inflammation
- Hemodynamic derangement
- Arrhythmias
- Cardiogenic shock
Diagnosis and Management
Diagnosis of fulminant myocarditis is aided by the use of biomarkers and cardiac imaging, with endocardial biopsy remaining the gold standard 2. Management involves intensive pharmacologic and interventional approaches, including the use of inotropic or mechanical circulatory support to maintain tissue perfusion 3, 4, 5.
- Biomarkers
- Cardiac imaging
- Endocardial biopsy
- Inotropic support
- Mechanical circulatory support
Role of Veno-Arterial Extracorporeal Membrane Oxygenation (VA-ECMO)
VA-ECMO has been shown to be effective in treating fulminant myocarditis, with short-term and long-term survival rates ranging from 57.1% to 78% and 65% to 94.1%, respectively 6. However, more research is needed to prove the efficacy of VA-ECMO for the treatment of fulminant myocarditis.
- Short-term survival rates: 57.1% to 78%
- Long-term survival rates: 65% to 94.1%
Importance of Early Recognition and Aggressive Management
Early recognition and aggressive management of fulminant myocarditis are essential for favorable outcomes 3, 2. Education of frontline providers is crucial to increase timely access to appropriately resourced facilities and to prevent multiorgan system failure.
- Early recognition
- Aggressive management
- Education of frontline providers
- Timely access to resourced facilities
- Prevention of multiorgan system failure