Intended for healthcare professionals

  1. Research
  2. Rivaroxaban treatment...
  3. Rivaroxaban treatment for six weeks versus three months in patients with symptomatic isolated distal deep vein thrombosis: randomised controlled trial
CCBYNC Open access
Research

Rivaroxaban treatment for six weeks versus three months in patients with symptomatic isolated distal deep vein thrombosis: randomised controlled trial

BMJ 2022; 379 doi: https://doi.org/10.1136/bmj-2022-072623 (Published 23 November 2022) Cite this as: BMJ 2022;379:e072623

All rapid responses

Rapid responses are electronic comments to the editor. They enable our users to debate issues raised in articles published on bmj.com. A rapid response is first posted online. If you need the URL (web address) of an individual response, simply click on the response headline and copy the URL from the browser window. A proportion of responses will, after editing, be published online and in the print journal as letters, which are indexed in PubMed. Rapid responses are not indexed in PubMed and they are not journal articles. The BMJ reserves the right to remove responses which are being wilfully misrepresented as published articles or when it is brought to our attention that a response spreads misinformation.

From March 2022, the word limit for rapid responses will be 600 words not including references and author details. We will no longer post responses that exceed this limit.

The word limit for letters selected from posted responses remains 300 words.

Re: Rivaroxaban treatment for six weeks versus three months in patients with symptomatic isolated distal deep vein thrombosis: randomised controlled trial

Dear Editor:
We read with interest the study by Dr. Ageno and colleagues[1], which reported that rivaroxaban administered for 6 additional weeks in patients with isolated distal deep vein thrombosis (IDDVT) after an uneventful 6-week treatment course reduced recurrent IDDVT within 2 years from 15% to 8%, compared to placebo. However, rivaroxaban carries the highest risk of major and minor bleeding among direct oral anticoagulants (DOACs).[2] A zero-event of major bleeding within 2 years in an RIDTS study [1] is beyond our rational expectation. Major bleeding was more frequently reported in the DRESDEN NOAC (4.31%) and FIRST (0.9%) registries, with corresponding annualized incidence rates of 2.51 and 1.16 per 100 patient‐years, respectively.[3] Dr. Ageno’s study likely excluded most patients with risk of bleeding using a long list of exclusion criteria.

Second, it is noteworthy that a 6-week anticoagulation therapy is suboptimal in current clinical practices. In the EINSTEIN CHOICE trial of rivaroxaban,[4] all study patients completed 6–12 months of rivaroxaban therapy and were in equipoise regarding the need for continued anticoagulation. Furthermore, two large real-world registry cohorts have reported overall median treatment durations of 144 days (25th–75th percentile, 85–337 days) and 214 days (25th–75th percentile, 105–640 days) in the FIRST and DRESDEN NOAC registries, respectively.[3] Finally, a previous meta-analysis reported a lower rate of recurrent venous thromboembolism in patients with isolated distal deep vein thrombosis (IDDVT) who received > 6 weeks of anticoagulant therapy than in those who received 6 weeks of anticoagulant therapy from four randomized studies.[5] Therefore, the study may be anticipated to provide additional information regarding the optimal duration of extended anti-coagulation therapy for patients with IDDVT.

1. Ageno W, Bertu L, Bucherini E, et al. BMJ 2022;379:e072623. https://doi.org/10.1136/bmj-2022-072623
2. Dawwas GK, Leonard CE, Lewis JD, Cuker A. Risk for Recurrent Venous Thromboembolism and Bleeding With Apixaban Compared With Rivaroxaban: An Analysis of Real-World Data. Ann Intern Med 2022;175:20-28. doi: 10.7326/M21-0717
3. Müller S, Tittl L, Speed V, et al. Pooled Analysis of Rivaroxaban therapy for acute venous thromboembolism in FIRST registry, SWIVTER and DRESDEN NOAC registry. Res Pract Thromb Haemost 2022;6:e12829. doi: 10.1002/rth2.12829
4. Weitz JI, Lensing AWA, Prins MH, B et al. Rivaroxaban or Aspirin for Extended Treatment of Venous Thromboembolism. N Engl J Med 2017;376:1211-1222. doi: 10.1056/NEJMoa1700518
5. Franco L, Giustozzi M, Agnelli G, Becattini C. Anticoagulation in patients with isolated distal deep vein thrombosis: a meta-analysis. J Thromb Haemost 2017;15:1142-1154. doi: 10.1111/jth.13677

Competing interests: No competing interests

09 December 2022
Nin-Chieh Hsu
Division chief, Division of Hospital Medicine, Department of Internal Medicine
Hung-Bin Tsai
Taipei City Hospital, and National Taiwan University Hospital
No.7, Zhongshan S. Rd, Taipei, Taiwan

Does it matter if the clot had resolved?

Dear Editor

Professor Ageno et al have made an excellent contribution to the literature with their randomized controlled trial of 6 vs 12 weeks rivaroxiban for isolated distal DVT. What was striking was that ~50% of patients in both groups had no residual clot at the randomization visit. Could the authors report the post hoc subgroup analysis for the primary and secondary thrombotic outcomes stratified by presence or absence of residual clot on the 6 week ultrasound? Perhaps there is still a means of determining who will or won't benefit from additional therapy.

Competing interests: No competing interests

24 November 2022
Todd C. Lee
Associate professor of medicine
McGill University
Royal Victoria Hospital, Montreal QC
Back to top