Unusual deep vein thrombosis sites: magnetic resonance venography in patients with negative compression ultrasound and symptomatic pulmonary embolism.

OBJECTIVES: To evaluate the clinical characteristics of patients with pulmonary embolism (PE), negative compression ultrasound (CUS) of the lower limbs and detection of unusual deep vein thrombosis (DVT) sites by means of magnetic resonance (MR) venography. METHODS: A retrospective data analysis of PE patients hospitalized at our institution from April 2009 to 2011. RESULTS: From April 2009 to 2011, a total of 762 PE patients were treated at our institution. In 169 of these patients CUS for DVT was negative. In these patients MR venography was performed for further evaluation. We found venous thrombosis at unusual sites in 12 of these patients. Due to free floating thrombus masses and fear of life-threatening PE progression we inserted an inferior vena cava filter in three of these 12 patients. The leading venous thromboembolism risk factor in our patients was immobilization (5 patients, 41.7%). CONCLUSIONS: We conclude that especially in patients with PE and negative CUS of the lower limbs a thrombosis of the pelvic veins should be considered in case of symptoms for venous thrombosis in this area. Further diagnostic work-up with MR venography should be scheduled in these patients especially in patients with risk factor immobilization as therapeutic consequences might occur.

Asymptomatic deep vein thrombosis and superficial vein thrombosis in ambulatory cancer patients: impact on short-term survival.

BACKGROUND: Asymptomatic venous thrombotic events (VTEs) are possible findings in ambulatory cancer patients. Data regarding the incidence and clinical impact of asymptomatic VTEs are conflicting. We therefore conducted a study to evaluate the occurrence of asymptomatic VTEs of the lower limbs in ambulatory cancer patients to further evaluate the association of these asymptomatic VTEs on survival during a 9-month follow-up period. METHODS: In our prospective cohort, we included 150 consecutive ambulatory cancer patients who were free of any clinical symptoms for VTEs. Compression ultrasound to detect deep vein thrombosis (DVT) and superficial venous thrombosis (SVT) of the lower limbs was performed by a vascular specialist in all patients at baseline. In case of pathological findings the patients were treated with low molecular weight heparin (LMWH) because of current established guidelines. The occurrence of death was investigated during a 9-month follow-up period. RESULTS: A total of 27 (18%) patients with VTEs were detected, which included 13 patients (8.7%) with a SVT and 16 patients (10.7%) showing a DVT. Two patients had both, a SVT and a DVT as well. During the 9-month follow-up period the occurrence of a VTE at baseline was associated with a 2.4-fold increased risk for death (HR 2.4 (1.2-5.3); P=0.03). CONCLUSION: Asymptomatic VTEs of the lower limbs in ambulatory cancer patients are frequently occurring concomitant features and are associated with poor survival during a 9-month follow-up period despite anticoagulation with LMWH.