Sudden cardiac death, borderline myocarditis and molecular diagnosis: evidence or assumption ?

Purpose: Sudden unexpected death autopsy is sometimes non-conclusive both from a macroscopic and from a histological point of view, even if carried out according to the guidelines for sudden cardiac death examination. Molecular biology techniques are required in this setting and may play a crucial role in reaching the final diagnosis. A case report: The postmortem examination and toxicology findings of the body of a young monk found dead in his cell were negative. Rare focal myocardial lymphocytic infiltrates were seen microscopically, associated with interstitial oedema. The findings were not sufficient to diagnose a myocarditis as the certain final cause of cardiac arrest. According to the recent guidelines for sudden cardiac death, a molecular investigation by polymerase chain reaction analysis was performed on samples of myocardium and spleen, with detection of parvovirus B19 DNA in the myocardium. Accordingly, a diagnosis of parvovirus B19 borderline acute myocarditis was put forward as the possible cause of sudden cardiac death. Conclusion: In sudden death cases in which there is lack of a cause–effect relationship with the postmortem findings, the final report should be expressed as a descriptive association of evidence, not providing unreliable certainty, as the Association for European Cardiovascular Pathology recommends.