Pulmonary tumor thrombotic microangiopathy associated with right ventricular rupture and hemopericardium: A case report.

Pulmonary tumor thrombotic microangiopathy is a rare form of pulmonary tumor embolism clinically indistinguishable from pulmonary thromboembolic disease. It is characterized by fibrocellular intimal proliferation of small pulmonary arteries and arterioles in patients with intraluminal tumor embolization. We report the case of a 67-year-old Caucasian woman who had been treated for breast cancer 5 years prior to presentation and had been free of recurrence on routine clinical surveillance. She was admitted for evaluation of three witnessed syncopal events accompanied by tachypnea and hypotension. Transthoracic echocardiography revealed severe right ventricular dilatation and severely reduced right ventricular function. Shortly after admission, the patient became acutely unresponsive and expired despite aggressive resuscitation measures. The proximate cause of death was a rupture of the right ventricular free wall and a large hemopericardium. Histopathology revealed extensive microscopic occlusions of small pulmonary arteries and arterioles by metastatic breast carcinoma with superimposed acute thrombi. Pulmonary tumor thrombotic microangiopathy should be included in the differential diagnosis of patients presenting with symptoms of pulmonary thromboembolism and a history of malignancy. <Learning objective: Pulmonary tumor thrombotic microangiopathy is a rare form of pulmonary tumor embolism clinically indistinguishable from pulmonary thromboembolic disease. It is characterized by fibrocellular intimal proliferation of small pulmonary arteries and arterioles in patients with intraluminal tumor embolization. The disease has a fulminant course and poor prognosis. It should be included in the differential diagnosis of patients presenting with symptoms of pulmonary thromboembolism and a history of malignancy.>.