Background: Isolated distal deep vein thrombosis (IDDVT) is often viewed to be of less clinical significance than major venous thromboembolism (VTE). However, studies report variable recurrence rate (2-19%) with significant heterogeneity in the IDDVT management.
Aims: To evaluate the characteristics of IDDVT in our study population.
Methods: Retrospective evaluation of IDDVT events managed at Northern Health, Melbourne, Australia from January 2012 to June 2019 (median follow-up 5.7 years). Analysis included demographics, associated factors, management and outcomes.
Results: 429 patients (median age 63 years (range 18-102), 56% females) presented with 438 cases of IDDVT in this time period. The majority (297 cases, 68%) were provoked, most commonly due to injury/immobility (n=142, 33%) followed by surgery (n=116, 26%). Prior VTE history was present in 82 (19%) cases. Twenty-nine patients (7%) had active malignancy at time of diagnosis. The median duration of anticoagulation was 3 months for provoked events compared to 4 months for unprovoked events (p=0.015). Warfarin was the most common anticoagulant used (189 cases, 43%), followed by direct oral anticoagulants (DOACs) (152, 35%). Of note, DOACs were only listed by Pharmaceutical Benefits Scheme for use in Australia in 2013. There were 53 (12%) patients with recurrent VTE (including 18 (34%) as major VTE) and 9 (2%) patients with clinically significant major bleeding. An analysis of the overall database demonstrated that IDDVT patients had comparable VTE recurrence rate to those with major VTE (12% vs 11%, p=0.44) but lower major bleeding rates (2% vs 4%, p=0.036). There were four bleeding-related deaths (all on warfarin/enoxaparin), with no thrombosis-related deaths. Fourteen cases (3%) were diagnosed with subsequent malignancy.
Conclusions: The majority of IDDVT were provoked although the risk of recurrent thrombosis was comparable to major VTE despite a lower major bleeding rate. These data suggest that IDDVT is not always as benign as assumed.
To cite this abstract in AMA style:
Lui B, Lai J, Khattak Z, Kwok A, Ho P, Lim HY. A Retrospective Evaluation of the Management of Isolated Distal Deep Vein Thrombosis in Australia [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/a-retrospective-evaluation-of-the-management-of-isolated-distal-deep-vein-thrombosis-in-australia/. Accessed September 24, 2023.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/a-retrospective-evaluation-of-the-management-of-isolated-distal-deep-vein-thrombosis-in-australia/