Chest
Clinical InvestigationsDiagnostic Utility of Ventilation/Perfusion Lung Scans in Acute Pulmonary Embolism Is Not Diminished by Pre-Existing Cardiac or Pulmonary Disease
Section snippets
Battent Enrollment
Patients reported in this investigation participated in the national collaborative study of the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED).1 The eligible study population consisted of patients ≥18 years old, in whom acute PE was of diagnostic concern. Symptoms suggestive of PE were required within 24 hours of entry into the study.1 In the present investigation, we evaluated patients who had no history or evidence of preexisting cardiac or pulmonary disease. There were
Ventilation/Perfusion Scans
Among patients with no pre-existing cardiac or pulmonary disease, PE was present in 50 of 54 (93 percent) in whom the V/Q scan was interpreted as highly probable for PE (Table 1). Among patients in whom the V/Q scan was interpreted as low probability for PE, 17 of 113 (15 percent) had PE. Among those in whom the V/Q scan was nearly normal/normal, 3 of 79 (4 percent) had PE. No patient in whom two independent readers both read the V/Q scans as normal showed PE on angiography or had recurrent
DISCUSSION
A number of conditions such as pneumonia or local bronchospasm cause perfusion defects.2 Ventilation scans were added to perfusion scans with the thought that ventilation would be abnormal in areas of pneumonia or local hypoventilation, but would be normal in PE.3 In the present study, it was shown that the positive predictive value of high probability V/Q scans was not significantly greater among patients without pre-existing cardiac or pulmonary disease than among patients with pre-existing
ACKNOWLEDGMENT
We thank Drs. Abass Alavi, Jack E. Juni, Charles A. Hales, and James H. Thrall for their special efforts in relation to this study, as well as all of the PIOPED investigators.
REFERENCES (6)
- et al.
Usefulness of noninvasive diagnostic tools for diagnosis of acute pulmonary embolism in patients with a normal chest radiograph.
Am J Cardiol
(1991) - The PIOPED Investigators. Value of the ventilation/perfusion scan in acute pulmonary embolism: Results of the...
- et al.
Regional pulmonary blood flow in man by radioisotope scanning.
JAMA
(1964)
Cited by (0)
This study was supported by contracts NO1-HR-34007, NO1-HR-34008, NO1-HR-34010, NO1-HR-34011, NO1-HR-34012, and NO1-HR-34013 from the National Heart, Lung, and Blood Institute, Bethesda, Maryland.
Manuscript received February 21; revision accepted April 15.