2 DVTs in my upper arm/One in my subclavial; This spontaneous case was reported by a consumer and describes the occurrence of DEEP VEIN THROMBOSIS (2 DVTs in my upper arm/One in my subclavial) in a 71-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 041821A and 044821A) for an unknown indication.     The patient's past medical history included Pacemaker insertion (cardiac) (2 weeks prior she had a pacemaker placed and was switched to Eliquis) since an unknown date. Concurrent medical conditions included RA, Clotting disorder and Haemophilia.   On 19-Mar-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 16-Apr-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On 12-Sep-2021,  after starting mRNA-1273 (Moderna COVID-19 Vaccine), the patient experienced DEEP VEIN THROMBOSIS (2 DVTs in my upper arm/One in my subclavial) (seriousness criterion medically significant). The patient was treated with APIXABAN (ELIQUIS) for DVT, at an unspecified dose and frequency and WARFARIN for DVT, at an unspecified dose and frequency. At the time of the report, DEEP VEIN THROMBOSIS (2 DVTs in my upper arm/One in my subclavial) outcome was unknown.        The action taken with mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) was unknown.       2 weeks prior patient had a pacemaker placed and was switched to Eliquis. patient went to the hospital where they switched her back to warfarin Company comment: This case concerns a 71 year old female patient, with reported medical history of clotting and bleeding disorder and Pacemaker insertion, who experienced the serious unexpected AESI of Deep vein thrombosis. The event occurred 4 months and 27 days after the administration of the second dose of mRNA-1273 vaccine and was assessed with the seriousness criteria of Medically significant. At the time of the report, the outcome of the event was reported as Unknown.  The rechallenge is unknown since no information on the event outcome has been provided. Reported medical history of clotting and bleeding disorder and report of pacemaker insertion two weeks prior to the reported adverse event remain as a confounder for the event. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.   This case was linked to MOD-2021-404643 (Link).; Sender's Comments: This case concerns a 71 year old female patient, with reported medical history of clotting and bleeding disorder and Pacemaker insertion, who experienced the serious unexpected AESI of Deep vein thrombosis. The event occurred 4 months and 27 days after the administration of the second dose of mRNA-1273 vaccine and was assessed with the seriousness criteria of Medically significant. At the time of the report, the outcome of the event was reported as Unknown.  The rechallenge is unknown since no information on the event outcome has been provided. Reported medical history of clotting and bleeding disorder and report of pacemaker insertion two weeks prior to the reported adverse event remain as a confounder for the event. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.