- Myocardial inflammation in the absence of ischaemia
- Often associated with pericarditis , termed myopericarditis
- The estimated incidence of myocarditis was 22 per 100,000 people, or approximately 1.5 million cases in the 2013 world population.
- occurs more commonly in males than in females.
- Myocarditis and/or pericarditis have been reported as rare side effects after COVID-19 vaccines particularly in young males aged 16-40 years. Cases have also rarely been reported in children
- Usually a benign disease without serious long-term complications
- In the acute setting can cause arrhythmias, cardiac failure, cardiogenic shock and death
- May result in delayed dilated cardiomyopathy
CAUSES (HIGAAP)
- hypersensitivity
- infectious/infiltrative (haemochromatosis or amyloidosis)
- giant cell myocarditis
- autoimmune (SLE, polymyositis, scleroderma, sarcoid)
- active viral (Coxsackie B, HIV)
- post viral (lymphocytic) – (rheumatic fever)
- mRNA Covid19 Vaccine
ASSESSMENT
HISTORY
- chest pain – is usually associated with concomitant pericarditis. However, myocarditis can mimic myocardial ischemia and/or infarction both clinically and on the electrocardiogram
- SOB
- palpitations
- fever
- malaise
- arthralgias
- fatigue and decreased exercise capacity
EXAMINATION
- fever
- tachycardia
- signs of fluid overload – increased jugular venous pressure, hepatomegaly, and peripheral edema
- direct evidence of cardiac dysfunction in symptomatic patients.
- S3 and occasionally S4 gallops are important signs of impaired ventricular function, particularly when biventricular acute myocardial involvement results in systemic and pulmonary congestion.
- If the right or left ventricular dilatation is severe, auscultation may reveal murmurs of functional mitral or tricuspid insufficiency.
- A pericardial friction rub and effusion may become evident in some patients with myopericarditis
- cardiogenic shock
INVESTIGATIONS
- elevated ESR, cardiac biomarkers, rheumatological markers
- Serology:
- enterovirus PCR/serology, parvovirus B19 PCR/serology, HHV6 PCR/serology, echovirus PCR/serology, coxsackie virus PCR/serology
- HIV
- HCV
- rheumatic fever: ASOT
- lupus screen. coeliac disease screen. anti-myosin antibodies. anti beta-1 adrenoreceptor antibodies
- quantiferon gold for TB
- ECG: sinus tachycardia, non-specific ST elevation, TW changes
- Chest Xray: The heart size on chest radiograph varies from normal to cardiomegaly with or without pulmonary vascular congestion and pleural effusions
MANAGEMENT
- treatment of HF
- low sodium diet
- cautious diuresis as needed
- ACE inhibitors
- Beta blockers
- intraaortic balloon pump/temporary LV assist device for intractable or when cardiogenic shock does not respond to medical therapy
- treatment of arrhythmia
- SVT – rate control therapy and antiarrhythmic therapy
- Sustained ventricular arrhythmias – urgent cardioversion
- Recurrent arrhythmias – antiarrhythmic drugs
- Symptomatic nonsustained ventricular tachycardia – antiarrhythmic drugs
- in select cases, anticoagulation (Thromboembolic complications can occur when HF is severe or protracted)
- Symptomatic HF with an LVEF below 20.
- Minimal risk factors for hemorrhage.
- A stable hemodynamic profile without evidence of liver synthetic dysfunction.
- Alcohol restriction
- to at most one alcoholic drink per day, since heavy alcohol intake may enhance the severity of the myocarditis
- avoidance of exercise
- reduce the work of the heart during the acute phase of myocarditis, especially when there is fever, active systemic infection, or HF
- NSAIDs — In animal models of myocarditis, nonsteroidal antiinflammatory drugs (NSAIDs) are not effective. To the contrary, they may actually enhance the myocarditic process and increase mortality.