Treatment of single peripheral pulmonary emboli: Patient outcomes and factors associated with decision to treat




Increasing use of computed tomography pulmonary angiography together with higher-resolution scanners has increased the detection of peripheral filling defects. Physicians face the dilemma of whether to treat patients with these findings, especially single defects. The aims of this study were to compare the outcomes of treated and untreated patients with single peripheral filling defects (SPFD) and identify factors associated with treatment.


All cases with SPFDs over 66 months in a single institution were identified. Patient and treatment information were abstracted and data on 90-day mortality and postdischarge venous thromboembolism (VTE) were collected.


A total of 4906 computed tomography pulmonary angiograms were reviewed. A SPFD was identified in 3.1% (n = 153). Of the 153 patients, 134 met criteria for study inclusion. In 99 of 134 (73.9%) studies, the defect was called a pulmonary embolus (PE) by the initial radiologist. Treatment was administered to 61 of 134 (45.5%) patients; 5 patients died in each group. Postdischarge VTE occurred in 3 treated and 2 untreated patients. In 52 of 153 cases, an additional study was performed. None of the patients with normal ventilation perfusion scan and compression ultrasound received treatment. Immobility (odds ratio [OR]: 3.90, 95% confidence interval [CI]: 1.45-10.60), previous VTE (OR: 3.72, 95% CI: 1.18-11.70), and determination of PE by the radiologist (OR: 24.68, 95% CI: 5.40–112.90) were associated with treatment.


There was no difference in 90-day mortality or recurrence between treated and untreated patients. The most influential factor associated with treatment was the radiologist's interpretation. When secondary lung imaging studies were negative, no patient received treatment. Journal of Hospital Medicine 2014;9:42–47. © 2013 Society of Hospital Medicine