Often clinically suspected, pulmonary embolism
(PE) is a potentially fatal disease. Because highly effective but
hazardous therapy exists, accurate diagnosis is extremely
important. Indeed, much of the research and publications on PE, such as
the Prospective Investigation of Pulmonary Embolism Diagnosis study,
pertain mainly to methods of diagnosis.
Prior to the development of imaging techniques, the diagnosis of PE was
based on a triad of dyspnea, hemoptysis, and chest pain, later shown to
be nonspecific and unreliable, for the clinical spectrum can range from
no symptoms at all to sudden death. The chest radiograph has been
equally nonspecific and unreliable in diagnosis of PE.