Polymerase chain reaction as a diagnostic tool in human viral myocarditis

Viral myocarditis is now acknowledged as a leading cause of morbidity as well as mortality in cardiovascular diseases. Its treatment is highly dependent on its proper diagnosis as its clinical features overlap with or mimic many other cardiovascular conditions. Histology by endomyocardial biopsy (EMB) confirms its diagnosis but given its own limitations and complications, the noninvasive imaging methods such as echocardiogram and magnetic resonance imaging as well as the molecular techniques like polymerase chain reaction (PCR) have redefined the entire scenario. Of these, PCR can detect the viral epitopes in peripheral blood samples, heart biopsy tissues samples, or urine/stool sample. Moreover, the best use of PCR is exemplified in the EMB samples where scarcity of the sample is not a limiting factor unlike histopathological examination. Detecting the subclinical infections, identifying different strains, and detecting pathogens which are otherwise difficult to grow gives PCR an edge. As it is said “time is money,” thus rapid detection of specific nucleic acid sequences from minute samples, and the overall cost-effectiveness makes PCR a technique of choice in the diagnostic armamentarium.