0
Original Research: Pulmonary Vascular Disease |

The Anticoagulation of Calf Thrombosis (ACT) ProjectThe Anticoagulation of Calf Thrombosis Project: Results From the Randomized Controlled External Pilot Trial

Daniel Horner, MD; Kerstin Hogg, PhD; Richard Body, PhD; Michael J. Nash, MD; Trevor Baglin, PhD; Kevin Mackway-Jones, MA
Author and Funding Information

From the Emergency Department (Drs Horner and Body and Mr Mackway-Jones), Manchester Royal Infirmary, and Department of Haematology (Dr Nash), Central Manchester University Hospitals, NHS Foundation Trust, Manchester, England; The University of Manchester (Drs Horner and Body and Mr Mackway-Jones), Manchester, England; Thrombosis Group (Dr Hogg), The Ottawa Hospital, Ottawa, ON, Canada; and Department of Haematology (Dr Baglin), Cambridge University Hospitals, NHS Foundation Trust, Cambridge, England.

CORRESPONDENCE TO: Daniel Horner, MD, Emergency Department, Central Manchester University Hospitals, NHS Foundation Trust, Oxford Rd, Manchester, M13 9WL, England; e-mail: danielhorner@nhs.net


Parts of this article were presented at the Annual Scientific Conference for the College of Emergency Medicine (United Kingdom and Ireland), September 2013, London, England, and at the XXIV Congress for the International Society on Thrombosis and Haemostasis, July 2013, Amsterdam, The Netherlands, and published in abstract form (Horner D, Hogg K, Body R, Nash MJ, Baglin T, Mackway-Jones K. Emerg Med J. 2013;30:869-870; winner of the Roderick Little Prize as highest scoring trainee abstract and subsequently published in the Emergency Medicine Journal and Horner D, Hogg K, Body R, Nash MJ, Baglin T, Mackway-Jones K. J Thromb Haemost. 2013;11(S2):845-846; winner of a Young Investigator award and subsequently published in the Journal of Thrombosis and Haemostasis).

FUNDING/SUPPORT: This work was funded by the College of Emergency Medicine and supported by the National Institute for Health Research through the comprehensive local research network.

Reproduction of this article is prohibited without written permission from the American College of Chest Physicians. See online for more details.


Chest. 2014;146(6):1468-1477. doi:10.1378/chest.14-0235
Text Size: A A A
Published online

BACKGROUND:  There is currently little evidence defining the clinical importance of detecting and treating isolated distal DVT (IDDVT). International guidelines vary regarding diagnostic and therapeutic advice. The potential benefits of anticoagulation are unquantified. We sought to evaluate the feasibility of a randomized controlled study within a modern framework and provide a primary outcome point estimate.

METHODS:  In this open-label, external pilot randomized controlled trial, consecutive, symptomatic, ambulatory patients with IDDVT were approached for inclusion. Participants were allocated to receive either therapeutic anticoagulation or conservative management. Patients underwent blinded color-duplex imaging at 7 and 21 days and follow-up at 3 months. Principal feasibility outcomes included recruitment rate and attrition. The principal clinical outcome was a composite including proximal propagation, pulmonary embolism, death attributable to VTE disease, or major bleeding. Analysis was by intention to treat.

RESULTS:  In total, 93 patients with IDDVT were screened, and 70 of those eligible (88.6%) were recruited. All patients but one were followed-up by direct contact after 90 days. Allocation crossover occurred in 15 patients (21.4%). The principal clinical outcome occurred in four of 35 of those conservatively treated (11.4%) and zero of 35 in the anticoagulated group (absolute risk reduction, 11.4%; 95% CI, −1.5 to 26.7, P = .11, number needed to treat of nine). There were no major bleeding episodes.

CONCLUSIONS:  We have established the feasibility of definitive study regarding the value of therapeutic anticoagulation in IDDVT and provide an approximate point estimate for serious complications with a contemporary conservative strategy.

TRIAL REGISTRY:  Current Controlled Trials; No.: ISRCTN75175695; URL: www.controlled-trials.com.

Figures in this Article

Sign In to Access Full Content

MEMBER & INDIVIDUAL SUBSCRIBER

Want Access?

NEW TO CHEST?

Become a CHEST member and receive a FREE subscription as a benefit of membership.

Individuals can purchase this article on ScienceDirect.

Individuals can purchase a subscription to the journal.

Individuals can purchase a subscription to the journal or buy individual articles.

Learn more about membership or Purchase a Full Subscription.

INSTITUTIONAL ACCESS

Institutional access is now available through ScienceDirect and can be purchased at myelsevier.com.

Sign In to Access Full Content

MEMBER & INDIVIDUAL SUBSCRIBER

Want Access?

NEW TO CHEST?

Become a CHEST member and receive a FREE subscription as a benefit of membership.

Individuals can purchase this article on ScienceDirect.

Individuals can purchase a subscription to the journal.

Individuals can purchase a subscription to the journal or buy individual articles.

Learn more about membership or Purchase a Full Subscription.

INSTITUTIONAL ACCESS

Institutional access is now available through ScienceDirect and can be purchased at myelsevier.com.

Figures

Tables

References

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Sign In to Access Full Content

MEMBER & INDIVIDUAL SUBSCRIBER

Want Access?

NEW TO CHEST?

Become a CHEST member and receive a FREE subscription as a benefit of membership.

Individuals can purchase this article on ScienceDirect.

Individuals can purchase a subscription to the journal.

Individuals can purchase a subscription to the journal or buy individual articles.

Learn more about membership or Purchase a Full Subscription.

INSTITUTIONAL ACCESS

Institutional access is now available through ScienceDirect and can be purchased at myelsevier.com.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Find Similar Articles
CHEST Journal Articles
  • CHEST Journal
    Print ISSN: 0012-3692
    Online ISSN: 1931-3543