Tuberculosis (TB), caused by Mycobacterium tuberculosis, is a major killer in the world and pulmonary
infections are well characterised. It is not widely known that TB
myocarditis leads to sudden cardiac deaths (SCD), especially in young people. Unlike other causes of SCD, risk factors such as family history are absent and patients are asymptomatic. This makes risk stratification and interventions with implantable cardiac
defibrillators extremely difficult. Only a few cases of TB
myocarditis SCD have been reported since 1977 and all of which were diagnosed at autopsy. The majority of reports showed extensive TB infiltration of the myocardium with no systemic symptoms. Concurrent miliary or systemic TB was postulated to be the source of TB
myocarditis. The mechanism of death has been hypothesized to be
ventricular tachyarrhythmia. Pulmonary TB has also been reported to cause
sudden death. However, ventricular arrhythmias have not been recorded, suggesting a different mechanism to TB
myocarditis SCD, which centres upon cardiopulmonary collapse leading to
bradycardia. Although anti-tuberculous
chemotherapy is efficacious in the treatment of TB
myocarditis, there is no evidence to suggest that it is effective in the prevention of SCD. It remains to be seen whether better global control of TB disease burden will result in reductions in SCD. Furthermore, no experimental data exist on the link between TB
myocarditis SCD and arrhythmias. We propose a unifying diagnostic system for TB
myocarditis based on the current data and molecular techniques. This is likely to require updates as more evidence becomes available.