Researchers at the University of Pennsylvania found that thoracic duct venous junction lymphoplasty (TDVL) can temporarily improve symptoms in patients with upstream obstructions of the thoracic duct (TD), according to abstract 188, “Thoracic Duct Venous Junction Lymphoplasty: Initial Experience and Outcomes,” which will be presented on Tuesday, March 7, at 4:03 p.m., in Room 222C of the Phoenix Convention Center.
“The lymphatic system offloads interstitial fluid back into the circulatory system,” said presenter Alexey Gurevich, MD, MS, an interventional radiology resident at the University of Pennsylvania’s Perelman School of Medicine. “Recent development of lymphatic imaging allows us to identify the obstructions or narrowing of the system in the distal part of the thoracic duct at the junction with the vein. What we set out to explore in this project was the effect of dilatation of the thoracic duct-venous junction. Basically, we do balloon angioplasty of the very distal end of the lymphatic system where it connects with the venous system.”
Because the lymphatic system uses the thoracic duct to transport lymphatic fluid, obstruction of TD outflow leads to an increase in intralymphatic pressures, which can cause a number of conditions such as lymphedema, chylous and nonchylous ascites, protein losing enteropathy, and abdominal pain.
“We hoped that the size increase of the lymphovenous junction will increase the flow of lymphatic fluid and therefore alleviate some of those symptoms,” said Dr. Gurevich.
The study, which consisted of 23 patients who underwent technically successful TDVL between September 2020 and May 2022, found that TDVL alleviated symptoms in 19 of 23 (82.6%) patients. Six patients experienced complete symptom resolution, three experienced partial resolution, 13 experienced temporary resolution and one did not experience improvement in symptoms. Patients with temporary resolution were symptom free for a median duration of 14 days, ranging from 5 to 180 days.
Though the data are promising, because of the high symptomatic recurrence rate, Dr. Gurevich says, TD venous decompression methods must continue to be researched and improved.
“We're seeing a lot of improvement in these patients’ symptoms, but symptoms appear to recur fairly quickly, which means that what we're doing alone is not enough,” he said. “But there's a lot of encouraging data that the symptoms they’re having may be related to the lymphatic obstruction since our short-term post-dilation window shows such drastic improvement. The flow may be the actual problem here, and balloon angioplasty may simply not be enough to keep the connection patent.”
Looking ahead, the researchers will be examining all the parameters of their procedure, Dr. Gurevich says.
“We're trying to determine the importance of balloon size,” he said. “We're going to see if drug-coated balloons are more effective for our purposes, or maybe even a placing stent at this junction as some other researchers have already done. There seems to be quite some promising data there, but ultimately it will be about making sure that connection stays open.”
Though some research was conducted in the 1960s and ’70s, the topic fell out of priority until recent researchers, such as Maxim Itkin, MD, FSIR, at the University of Pennsylvania, have begun investigating again, Dr. Gurevich said. “It's a pretty niche subject because not a lot of people know that you can intervene on the lymphatic system,” he said.
The improvement in these patients’ symptoms, even if temporary, illustrates the pathophysiological mechanism of these diseases, Dr. Gurevich says.
“This is definitely an exciting part of interventional research that tries to further our understanding of the lymphatic system and how it connects to the circulatory and hemodynamic physiology in our body,” he said. “We're looking forward to doing more.”
