Acute right ventricular infarction secondary to massive pulmonary embolism

Isolated right ventricular infarction has been found in cases of right ventricular hypertrophy, but there are no reports on right ventricular infarction secondary to massive pulmonary embolism. Six autopsied patients with massive pulmonary embolism and pure right ventricular infarction, suspected to be secondary to the embolism, were selected from a population of 216 autopsies. Pulmonary embolism was the suspected diagnosis in five cases due to typical clinical, electrocardiographic and haemodynamic data. Right ventricular infarction was a post-mortem finding, not previously diagnosed. In every case the thickness of the right ventricular myocardium was normal. The necrosis of the right ventricle was transmural in four cases and subendocardial in two and the entire right ventricular wall (anterolateral as well as posterior) was involved. No mural thrombi were present and in no case did the necrosis involve the left ventricle. In one case the coronary arteries were normal, in the other five significant lesions of the right or left coronary arteries were observed. These lesions may have been, in part, responsible for the necrosis of the right ventricle when the massive pulmonary embolism was added. We conclude that right ventricular infarction may be secondary to pulmonary hypertension in the setting of massive pulmonary embolism, even in the absence of right ventricular hypertrophy and with normal or stenotic coronary arteries.