The objectives of this registry are to measure the outcomes, cost, adherence pattern and experience of patients treated as outpatients with rivaroxaban after being diagnosed with blood clots in the emergency department. The investigators hypothesize that patients will have a relatively low rate of adverse events and higher adherence than has been reported historically for warfarin treatment. Patients will be scheduled for follow up care with one of Dr. Kline's Outpatient Thrombosis clinics at Methodist Hospital, Eskenazi Health Services and the Baylor University Medical Center (Dallas, TX) after diagnosis and treatment of pulmonary embolism (PE) or deep vein thrombosis (DVT).

Information will be obtained from the patient medical records, past medical history, physical examination at initial outpatient clinic visit 30 days (+/- 14 days) and 6 months or 180 days (+/- 14 days) post diagnosis or start of treatment, then annual follow ups for up to 5 years. The data will be collected and stored in a database, the IU RedCap database system will be used to develop a database and store information .

Inclusion:

• DVT or PE diagnosed on imaging:
• Systolic always>100 mm Hg in absence of history of low blood pressure
• No contraindication to anticoagulation treatment (active bleeding or high risk postoperative status, creatinine clearance < 30 ml/min, history of heparin induced thrombocytopenia or warfarin skin necrosis);
• No other medical condition requiring hospital treatment (sepsis, new or decompensated existing organ failure, intractable pain);
• No social condition requiring hospital treatment (homelessness with history of non-adherence to treatment, suspected neglect or abuse, incarceration, untreated psychosis, severe alcohol or drug dependency);
• No coagulopathy or current anticoagulant resulting in an INR>1.7, or thrombocytopenia (platelet count < 50,000/uL);
• No need for supplemental oxygen (no respiratory distress and pulse ox always >94%)

Exclusion:

- If active cancer, POMPE-C <6%

Heterogeneous group of patients pulled primarily from an emergency department population, diagnosed with low-risk VTE.