Massive pulmonary embolism with large floating thrombus in the truncus of the pulmonary artery.

A conservative strategy with anticoagulation led to spontaneous dissolution of a large floating thrombus (7.0x0.5 cm) in the truncus of the pulmonary artery in a 51-year-old woman with massive pulmonary embolism (pulmonary emboli in both lungs down to the level of the segmental arteries). Interventional therapy such as thrombolysis or pulmonary thrombectomy was not considered to be appropriate for this patient because of the risk of disrupture and embolization of parts of this large central thrombus. We believe that in certain cases with massive pulmonary embolism and large floating central thrombi a conservative strategy with anticoagulation may be appropriate. Such cases may be observed more often in the future using the technique of spiral computed tomographic angiography.