Whether to Treat Subsegmental PE Summary of the Evidence Subsegmental PE refers to PE that is con ned to the subsegmental pulmonary arteries. Whether these patients should be treated, a question that was not addressed in AT9, has grown in importance because improvements in CT pulmonary angiography have increased how often subsegmental PE is diagnosed (ie, from approximately 5% to more than 10% of TABLE 16 ] Summary of Findings: Temporary IVC Filter vs No Temporary IVC Filter in Addition to Anticoagulation for Acute DVT or PEa,b Outcomes No. of Participants (Studies) Follow-up Quality of the Evidence (GRADE) Relative Effect Anticipated Absolute Effects Risk With No Temporary IVC Filter in Addition to Anticoagulation Risk Difference with Temporary IVC Filter (95% CI) All-cause mortality Moderatec,d because of imprecision (from 24 fewer to 96 more) Recurrent PE 399 Moderatec,d because of imprecision (from 7 fewer to 104 more) Major bleeding 399 Moderatec,d because of imprecision (from 34 fewer to 49 more) The basis for the assumed risk (eg, the median control group risk across studies) is provided in the footnotes. The corresponding risk (and its 95% CI) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). IVC inferior vena cava. See Table 1 and 4 legends for expansion of other abbreviations and GRADE Working Group grades of evidence. a All patients received full-dose anticoagulant therapy according to guidelines for at least 6 mo. b Filter removal was attempted in 164 patients and successful for 153 (93.3%). c CI includes values suggesting no effect and values suggesting either bene t or harm. d Small number of events. Bibliography: Mismetti et al237 There is uncertainty whether these patients should be anticoagulated for two reasons. 