Marantic endocarditis – A not so benign entity

Marantic, verrucous or nonbacterial thrombotic endocarditis, is characterised by the deposition of an amorphous mixture of fibrin and platelets onto heart valves. Although not commonly a cause of death in forensic practice, it may be associated with systemic embolisation. This was observed in a 60-year-old woman who suddenly collapsed and was found at autopsy to have a poorly differentiated adenocarcinoma of the lung with vegetations from marantic endocarditis on the mitral valve and embolisation with infarcts in the left kidney, the spleen, the right occipital cortex of the brain and the left ventricle of the heart. Death was due to coronary artery embolism from marantic endocarditis associated with an undiagnosed adenocarcinoma of the lung. Although marantic endocarditis is more common in hospital autopsies than in forensic cases, it can have lethal complications that result in sudden and unexpected death. Histories of debilitating disease and/or arterial thromboembolic episodes necessitate meticulous examination of the cardiac valves with careful serial sectioning of the major epicardial coronary arteries and histologic sampling of both ventricles.