Multidetector CT scan(CTPA)has significantly improved the detection of subsegmental pulmonary emboli(SSPE). In the absence of deep venous thrombosis(DVT), the significance of SSPE and the need for treatment has been questioned. We retrospectively determined if clinicians treated SSPE and report on the frequency of treatment complicatons.
We reviewed the reports of 2726 consecutive CTPA performed from 1/1/2007 through 12/31/2007 at 3 northeastern US community hospitals. CTPA were performed on either 4-, 8-, 16- or 64-detector scanners using 1.25 mm reconstructions. A specialist chest radiologist with 18 years of experience reviewed all CTPA reported positive for pulmonary embolism(PE) and categorized each CTPA by location of the largest PE identified. A clinician reviewed all hospital records contemporary with the CTPA positive for SSPE and all hospital records for the subsequent 6 months.
Our specialist chest radiologist identified 228 CTPA positive for PE. 54/228 (23%)were SSPE. 5 patients were excluded (4 with proximal DVT and 1 who was comfort care). 46/49(92%) were treated with therapeutic anticoagulation and/or inferior vena cava(IVC) filter placement. Three patients were treated with IVC filter alone. 6/43(14%) treated with therapeutic anticoagulation had bleeding requiring transfusion and 2 of these patients required surgery. In addition 2/43(5%) died of intracranial hemorrhage. Anticoagulation potentially contributed to the development of pericardial tamponade in another patient.
The overwhelming majority of patients with SSPE detected by CTPA were treated with therapeutic anticoagulation and/or IVC filter placement. The morbidity and mortality associated with anticoagulation was significant in the treated group.
Given the significant risk of treatment, further study is warranted to determine if patients with SSPE without DVT can safely avoid therapeutic anticoagulation and IVC filter placement.
Lawrence Marinari, Supported by the Sharpe-Strumia Research Foundation of the Bryn Mawr Hospital.; No Product/Research Disclosure Information