The Future of Treatment of Venous Thromboembolism Is Single-session/On-table Therapy

The future of venous thrombosis treatment was tackled in a VIVA@LINC session on Wednesday afternoon by Robert Lookstein, Professor of Radiology and Surgery at the Icahn School of Medicine at Mount Sinai (New York, NY, USA). “In the last 25 years, there have been significant advancements in minimally invasive treatments of venous thromboembolism,” Dr Lookstein said in conversation with LINC Today. “From my perspective, this is one of the most exciting fields in cardiovascular medicine right now.”

Looking back to the mid-1990s, Dr Lookstein recalled how the predominant endovascular therapeutic option was catheter-directed thrombolysis. “This was highly effective, but one major criticism of this treatment was the lengthy time it took to demonstrate clinical benefits,” he added. Typical treatment times for iliofemoral deep vein thrombosis were over 48 hours, for example. “Another criticism was the relatively high doses of a fibrinolytic agent administered to the patient to achieve such benefits.”

The turn of the millennium brought tremendous enthusiasm for percutaneous mechanical thrombectomy systems. The assumption was that they might actually replace catheter-directed thrombolysis. Numerous operators around the world attempted to use the first generation of thrombectomy systems to support a strategy of so-called single-session or on-the-table therapy. “Unfortunately, these first-generation devices were not sophisticated enough to achieve this lofty goal,” Dr Lookstein underlined.

That is why the concept of the so-called combination therapy emerged, where thrombectomy systems were used to deliver a relatively low dose of a fibrinolytic agent into the thrombus prior to utilizing the mechanical thrombectomy system. “This advance allowed treatment times to decrease dramatically,” commented Dr Lookstein. Instead of treatments occurring over several days, with combination therapy or ‘pharmaco-mechanical’ thrombolysis, times are reduced to 18–24 hours. 

Importantly, second-generation mechanical thrombectomy systems have emerged over the last decade. These devices offer tremendous benefits over the first-generation devices, typically involving manual or vacuum-assisted aspiration, explained Dr Lookstein. They also have the potential to offer these on-the-table or single-session thrombectomy procedures to acutely symptomatic patients. “While these devices are not ideal—and have been criticized due to the observed blood loss as well as some subacute re-thrombosis rates—it is clear that the technology is moving in the right direction,” he said.

Nevertheless, the community is looking optimistically to the future of such approaches, noted Dr Lookstein: “We might see a re-emergence of combination therapy where these second-generation mechanical thrombectomy systems can deliver a relatively low dose of a fibrinolytic agent into the acute thrombus. With the increased efficacy of these newer thrombectomy systems, it is likely that they will be able to achieve single-session reliably and safely while offering minimal blood loss and incredibly short procedure times.”

As such, this is a unique opportunity in the history of the treatment of venous thromboembolism, continued Dr Lookstein. Countless research studies are currently underway studying endovascular therapy for deep vein thrombosis as well as pulmonary embolism. “I am extremely optimistic that we are entering an era where single-session therapy will become the standard of care for the minimally invasive treatment of venous thromboembolism around the globe,” he added.

To that end, Dr Lookstein said he would encourage all endovascular operators and vascular specialists to contribute to prospective data trials, including pivotal randomized data and independently adjudicated single-arm studies, to demonstrate which patients benefit most from this novel therapeutic option. “That would allow all of us, as global vascular specialists, to learn from our collective experience,” he said. “The future is very bright. I am looking forward to multiple data sets emerging over the next few years that will hopefully answer these important, previously unanswered, questions.”