Radiological (scintigraphic) evaluation of patients with suspected pulmonary thromboembolism

THE OPTIMAL strategy for diagnostic evaluation of patients with suspected pulmonary thromboembolism (PE) is a subject of controversial and often conflicting opinions. If untreated, as many as 30% of patients with PE may die. Conversely, anticoagulant therapy significantly decreases mortality from PE, but bleeding complications occur. Underdiagnosis may result in a preventable death, and overdiagnosis may lead to significant hemorrhage from unnecessary anticoagulant therapy. This article outlines a practical guide for the use of pulmonary ventilation-perfusion (V-P) scintigraphy in patients with suspected PE. The clinical diagnosis of PE is rarely simple and often inaccurate. Autopsy series have disclosed that fatal PE commonly is unrecognized before death, particularly in elderly patients and in patients with congestive heart failure or pneumonia. The symptoms, physical signs, routine laboratory findings, and standard roentgenographic studies of the chest frequently are inconclusive. Dyspnea, pleuritic chest pain, and apprehension are the most common presenting symptoms in patients