6 – Miscellaneous
The future management of acute and chronic venous disease:
report from the American Venous Forum’s Hawaiian Summit in 2006
B. Eklof / Sweden
At the American Venous Forum (AVF) in Washington DC in September 2004, three major goals were formulated:
• to create a curriculum in venous disease for the new fellowship program in vascular surgery in collaboration with the program directors,
• to introduce a national screening program for venous disease in collaboration with the American Vascular Association (AVA),
• to organize a meeting of experts to draw up the guidelines for venous disease research and development over the next 5-10 years.
Thanks to help from many AVF members, Joann Lohr submitted the venous curriculum to the program directors in early 2006. The screening program for venous disease started in the fall of 2005 through the efforts of Robert McLafferty and his committee, in collaboration with the AVA.
The 5th Pacific Vascular Symposium on January 20-24, 2006 in Hawaii covered the following topic: “Mapping the future of venous disease, an international summit”.
In the invitation to the experts, we wrote: “Would you be willing to explore where the field stands at present, to identify where sticking points; and perhaps… propel the field into a new orbit, by defining the next 5-10 years, including postulation of research and development priorities?”. Sixty experts were invited representing all the continents and several specialties—angiology, clinical physiology, dermatology, interventional radiology, thrombosis / hemostasis, and vascular surgery. Twelve experts represented industrial research and development for artificial valves and stents, compression therapy, obliteration of veins using laser or radiofrequency, pharmacologic and mechanical endovenous thrombus removal, venotonic drugs, and wound care. Before the meeting, 32 AVF members had each produced an updated report on the state of the art in acute and chronic venous disease, reports that were sent to all participants before the meeting.
The first day was a conventional meeting with presentation of the 32 reports. The following four days were completely different, as the meeting was taken over by four professional facilitators, who each took care of one of the four groups into which we were divided: diagnostics/hemodynamics, acute venous thromboembolism, primary chronic venous disease, and secondary chronic venous disease. Irv Rubin, the chief facilitator, said that “This will be a dramatic departure from the previous symposium format. Using an intense fast-pace novel process my colleagues and I will ask you to join in with open-minded and open-hearted full participation, and we are confident that you will be able to shape the future to hasten beneficial change in the way you treat your patients”. The process was built on the theory of “Appreciative inquiry—a positive approach to building cooperative capacity where the four D’s can describe the phases of activity: discovery, dream, design, and destiny”. Alternating between break-out sessions for the groups and plenary sessions where the group outcomes were discussed, the second day was devoted to the issue “Where have we come to in our field— the discovery phase” followed by “Sharpening a vision for the future—the dreaming phase”. The third day we were “defining and prioritizing critical issues—the design phase”, which was further discussed during the fourth day when we were defining a plan of action for the next ten years. During the fifth and last day the plan of action was discussed with commitment from the experts to participate in special projects, and ways to monitor progress of the projects—the destiny phase.
IMUA mission statement: to promote venous health through innovative research, education and technology.
The AVF created a committee to follow up the meeting, the IMUA committee (IMUA is Hawaiian for moving forward!) with the following members: Bo Eklof (chair), Peter Gloviczki, Robert Kistner, Joann Lohr, Fedor Lurie (secr), Mark Meissner, Gregory Moneta and Thomas Wakefield, and we have added Michael Dalsing (AVF President), Brajesh Lal (Chair of AVF research committee) and Sardra Shaw (Chair of AVF’s industrial advisory committee). Each of the four groups came up with >20 projects. These >80 projects were reduced to 21 after voting within the groups and at the plenary sessions, and the IMUA committee has merged and reduced the number to 14 projects: 12 investigational and 2 administrative projects. AVF members have volunteered to initially lead these 14 projects:
1 – MR outflow obstruction of venous disease. PI Mark Meissner
a. Explore the use of MRV for assessing venous obstruction
b. Use CINE-gated MRV to evaluate and quantify outflow obstruction
c. Perform pre- and post-therapy testing
2 – Duplex ultrasound in diagnosis and prognosis of DVT. PI Mark Meissner
a. To evaluate if a single US is sufficient for the evaluation of acute DVT
b. Produce better guidelines for diagnosing acute DVT and define adequate scan techniques
c. Evaluate the natural history of DVT in relation to the characteristics of the thrombus
3 – Early clot removal. PI Tony Comerota a. Create
a multicenter international RCT comparing
b. Catheter-directed thrombolysis
c. Endovenous mechanical/pharmacological thrombectomy
d. Vs anticoagulated controls
e. Assessing iliofemoral patency, femoropopliteal competence and quality of life
4 – Biomarkers in diagnosis and prognosis of DVT. PI Thomas Wakefield and Tony Comerota
a. To study the utility of biomarkers such as D-dimers, TAT, F1-2 and PAI-1 antigen in diagnosing DVT and for providing prognostic information to guide type and duration of therapy
b. End points will include thrombus extension, recurrence and incidence of PE
5 – Core-lab consortium and genetic database. PI Peter Pappas
a. To identify measuring parameters at the tissue level: vein skin/blood samples
b. Specimens bank, analysis, database
c. Correlation between genes, the inflammatory reaction and clinical status of CVD
d. A repository of information for researchers, drug industry
6 – Evaluation and standardization of venous testing. PI Fedor Lurie
a. Standardize testing for acute and chronic venous disease for both clinical practice and research
b. Identify a standard for quality of life outcomes and hemodynamic outcomes
c. Develop uniform protocols d. Develop a wireless functional venous test to enable real-time study during exercise
7 – Assessment of reflux and its relation to progress of CVD. PI Joann Lohr
a. Correlate patterns of reflux parameters that most accurately identify CEAP categories
b. Identify patterns of reflux that will identify those patients who will go on to develop class 3-6 clinical signs
c. Develop a severity score for valvular incompetence
8 – IVC filters in trauma patients. PI David Gillespie
a. To develop a prospective study comparing
b. Permanent IVC filters vs
c. Removable IVC filters vs
d. A strategy of DVT surveillance
e. In trauma patients and patients with intracerebral hemorrhage
9 – Improvement of existing endovenous valves and venoscopic valve repair. PI Seshadri Raju
a. Develop a valve which is nonthrombogenic, nonimmunogenic, flexible and size-adaptable to all venous segments
b. Develop the least invasive techniques to restore valve function
10 – Pathophysiology in chronic venous disease. PI Joseph Raffetto
a. Hypothesis: capillary endothelium contains the sensor mechanism which detects the blood flow changes produced by venous hypertension
b. Plan human and animal experiments to assess role of endothelium and identify mechanisms of ambulatory venous hypertension, inflammatory skin changes and ulceration.
11 – External compression device. PI Joseph Caprini
a. To develop a compression device to treat severe stages of CVI that
b. Is as portable as compression stockings
c. Is easy to use
d. Responds to patient movements and position
e. Positively assists venous return f. Gives feedback to the physician
12 – Development of dedicated venous stent. PI Peter Neglen
a. To create a modular stent system for caval confluence
b. Identification of vessel reaction to stent material
c. Rate of in-stent restenosis and nature of mechanism
d. Assess modification by preoperative pharmacotherapy
13 – Joint Venous Council. PI Robert Kistner
a. To form a new organization
b. To raise awareness about venous disorders among physicians, government, industry, and the general public
c. To foster relationships with industry, government, academics and pertinent national and international societies
d. To consolidate resources to minimize duplication of effort and to maximize progress in the field
e. To identify and develop sources of funding and other support for the activities needed to advance the venous field
14 – AVF a broad-based inclusive organization. PI Michael Dalsing
a. Achieve influence through critical mass and excellence
b. Act as project/grant clearing house
c. Create evidence-based practice guidelines
The IMUA committee’s tasks are to:
– Produce a supplement for Journal of Vascular Surgery containing the 32 guidelines and the proceedings from the Venous Summit. A 370-page manuscript is submitted: publication planned in the summer of 2007.
– Support and encourage completion of the projects.
Contemporary approach to Budd-Chiari syndrome among Asians with endovascular management
B.B. Lee, J. Laredo, D. Deaton, R. Neville / USA
Budd-Chiari syndrome (BCS) is hepatic venous outflow obstruction at the suprahepatic inferior vena cava and/or hepatic veins. There are various primary and secondary causes of BSC: congenital, inflammatory, infectious, etc.
Primary, idiopathic BCS is a relatively rare condition with great geographic variance and etiologic or predisposing factors that differ between Caucasian and Asian patients. The “thrombosis theory” is more compatible with the situation in Caucasian patients than the “developmental anomaly theory”, which is more frequently relevant in Asian and African patients. Management strategy remains a critical issue: decompression procedure versus curative radical procedure. Today the gold standard of interventional treatment for different types of BCS has not been established. Thus the indication for combination of various surgical and endovascular procedures needs further investigation.
The last study of an Asian population revealed that the initial process leading to BCS starts during embryogenesis and is related to pathological formation of the vitelline vein and umbilical veins. All these produce an outflow obstruction on the proximal hepatic veins or supraphrenic part of the inferior vena cava. The majority cases of BCS in Asian populations are related to the segmental stricture of the supraphrenic segment of the IVC and/or malformations of the hepatic veins. Pathological segmental venous hypertension results in hepatic vein thrombosis. So, decompression of hepatic outflow seems to be very important. In many cases it can be achieved by endovascular procedures—endovascular balloon decompression of the supraphrenic part of the IVC with or without stent placement even after IVC thrombosis. When it is not possible to obtain IVC decompression, or if BCS is related to hepatic vein malformation, cirrhosis and hepatocellular carcinoma are subsequently common in these patients.
Transjugular intrahepatic portosystemic shunt (TIPS), a typical endovascular procedure, is very useful for treatment of patients without obstruction of the supraphrenic segment of the IVC. This procedure is widely performed in Europe and Japan. However, the benefits of this procedure are very limited for patients who present with IVC stricture or malformation of hepatic veins. Liver transplantation is possible, but not a good solution because the long-term results are poor. So prophylaxis against BCS seems to be very important for Asian and African patients, optimal medical treatment being conditional upon early diagnosis of the IVC stricture or segmental hepatic vein hypertension.