The DUET study, a randomised trial conducted to compare standard catheter-directed thrombolysis vs. ultrasound-accelerated thrombolysis in The Netherlands, has begun enrolment of its 60 thrombo-embolic infra-inguinal disease patients.
To be eligible, patients should have recently (between one and seven weeks) thrombosed infra-inguinal native arteries or bypass grafts with acute limb ischaemia Rutherford class I and IIa. Patients will be randomly allocated to either standard thrombolysis or EKOS ultrasound-accelerated thrombolysis. The anticipated duration of recruitment will be one year.
Jean-Paul de Vries and AM Schrijver, investigators at St Antonius Hospital, Nieuwegein, will include patients number eight and nine in the beginning of April 2010. In May, four other Dutch institutions will begin enrolment.
De Vries spoke to Vascular News on the DUET trial.
The DUET trial hypothesis is that ultrasound-accelerated thrombolysis will reduce therapy time by at least 12 hours compared to standard thrombolysis with no difference in complication rates. If confirmed, what other benefits will this time reduction bring to physicians and patients?
Jean-Paul de Vries: Twelve-hour reduction of thrombolysis might prevent patients from severe bleeding complications which are increased with thrombolysis time and doses. It will reduce hospital stay, which is of benefit for both patients and physicians. Furthermore the overall costs will decrease with shorter thrombolysis time.
What is the current status of the trial?
De Vries: The St Antonius Hospital will include patient number eight and nine next week. Four other large vascular Dutch hospitals will start to include within six weeks. The trial is expected to complete enrolment by the beginning of 2011.
Could you tell us about your personal experience with ultrasound-accelerated thrombolysis?
De Vries: My personal experience with ultrasound accelerated thrombolysis is mainly on arterial occlusion of the native peripheral arteries or occluded femoropopliteal bypasses. Until now we have treated more than 15 patients in our hospital and more than 85% had successful clot lysis within 24 hours. Most of the patients suffered from arterial obstruction for more than two weeks.
If ultrasound-accelerated thrombolysis is successful in this study, what would be the next step in the investigation?
De Vries: If the benefit of ultrasound accelerated thrombolysis is proven in the DUET study, the next step is to refine the technique and determine whether more intensive ultrasound techniques will further reduce thrombolysis time. Another project is the evaluation of the optimal anticoagulant regimen during thrombolysis. The third interesting study which is running is the use of ultrasound accelerated thrombolysis in patients with arterial occlusions more than 12 weeks old.