The 37th annual Veith Symposium was held from November 17 to 21 in New York City. The features below highlight some of the news emerging from the meeting.
Analyzing Different Stenting Approaches for Restenosis
The Particulars: Few studies have compared the use of drug-eluting stents after angioplasty with balloon angioplasty and bare-metal stenting in the treatment of restenosis. The Zilver PTX (Cook Medical, Inc.) is the first drug-eluting stent approved for the superficial femoral artery and is currently under investigation in the United States for use in restenosis. Researchers conducted a study comparing the Zilver PTX drug-eluting stent after angioplasty with balloon angioplasty and bare-metal stenting.
Data Breakdown: The study enrolled 479 patients at 56 institutions in the United States, Japan, and Germany, with 241 patients randomized to the Zilver PTX group and 238 to the bare-metal stenting group. Demographics and lesion characteristics were similar for the groups. Approximately, half of the bare-metal stenting group experienced acute failure and underwent secondary randomization in which 59 and 61 patients were assigned to provisional stenting with Zilver bare-metal stents and Zilver PTX, respectively. Study results met the 12-month primary endpoint goals showing non-inferiority and superior patency for the Zilver PTX as compared with a bare-metal stenting group. Endpoints included event-free survival, stent integrity by radiographic core laboratory analysis, and primary patency by Duplex ultrasound core laboratory analysis. There was also significant clinical improvement with the Zilver PTX.
Take Home Pearl: The Zilver PTX drug-eluting peripheral stent appears to be safe and effective for the treatment of restenosis when compared with bare-metal stenting.
Ultrasound-Accelerated CDT Beneficial in PE Treatment
The Particulars: Pulmonary embolism (PE) accounts for more than 300,000 deaths every year in the United States, and most of these result from acute massive PE and typically occur within 1 hour of presentation. For patients with hemodynamic instability from massive PE, systemic thrombolysis is considered to be the standard of care. Ultrasound-accelerated catheter-directed thrombolysis (CDT), developed by EKOS Corporation) was explored. It combines the energy of ultrasound with highly targeted delivery of clot-busting drugs, and adds a new dimension to CDT.
Data Breakdown: Researchers reported on the results of a study of 46 patients treated for massive PE over a 10-year period. Ultrasound-accelerated CDT achieved complete thrombolysis in 100% of the patients treated, compared with 67% patients receiving CDT without ultrasound. The average dose of thrombolytic agent and the length of time for infusion were lower for patients receiving ultrasound-accelerated CDT. Furthermore, there were no hemorrhagic complications within the ultrasound-accelerated CDT group (compared with three incidents in the CDT group).
Take Home Pearls: In institutions with appropriate clinical expertise, ultrasound-accelerated CDT appears to be a beneficial treatment option in patients who have acute massive PE with contraindications to systemic thrombolysis when time to administer systemic thrombolytic agents is lacking or when no improvement follows standard IV thrombolytic administration. Ultrasound-accelerated CDT appears to provide a significant added benefit of clearing most (if not all) of the clot while using less drug.
A New Device for Peripheral & Visceral Aneurysms
The Particulars: The usual treatments for peripheral or visceral aneurysms include embolization with coils or exclusion by graft. Despite the good results that have been achieved in the past, these techniques have some limitations. A multilayer stent (Cardiatis Multilayer Stent, Cardiatis SA) was assessed in the treatment of peripheral and visceral aneurysms with/without collateral branches arising from the sac or proximal/distal neck. The device bases its technology on velocity vortex control in the aneurysm and lamination of the flow in collateral vessels arising from the lesion allowing patency of the aneurismal branches.
Data Breakdown: A study followed 54 patients, 35 with peripheral aneurysms and 19 with visceral aneurysms, who were treated with the Cardiatis Multilayer Stent. Patients were evaluated at 1, 3, and 6 months after their procedures, and were assessed for clinical success (aneurysm thrombosis, stent, and branches patency). Shrinkage of the sac at 6 months was also assessed. Clinical success rates were 88.9% at 1 month, 93.3% at 3 months, and 100% at 6 months. Results showed a 100% rate of side branches patency and a 93.3% rate of stent patency at the latest follow-up. Shrinkage at 1-month follow-up was observed in 52.4% of patients, but was present in 93.7% of patients at 6-months follow-up.
Take Home Pearls: Based on preliminary experience, the Cardiatis Multilayer Stent appears to be an effective tool in endovascular exclusion of peripheral and visceral aneurysms with collateral branches and significant shrinkage of the sac. This allows a broader group of patients to be treated with endovascular repair. Further studies are needed to evaluate the long-term results.
Surgical Hope for MS?
The Particulars: Previous research has suggested that some symptoms of multiple sclerosis (MS) may be related to blockages in the veins that drain blood from the brain and spine. Endovascular interventions that increase blood flow in those veins may provide significant relief and improve quality of life. It has been estimated that the vast majority of people with an MS diagnosis have chronic cerebrospinal venous insufficiency (CCSVI).
Data Breakdown: Researcher studied 65 MS patients diagnosed with CCSVI who had either percutaneous transluminal angioplasty (PTA) or stents inserted for blockages in their internal jugular and/or azygous veins. PTA was performed in the majority of cases, with the stenting procedure used in selective cases of azygous vein twisting. All of the patients were already taking FDA-approved medications for MS. Clinical outcome measures were significantly improved by the PTA treatment. The rates of relapse-free patients increased from 27% to 50% postoperatively, and the number of active lesions detected under MRI was reduced from 50% to 12%. After 1 year, patient scores on the degree of impairment had improved significantly, as did mental and physical quality-of-life scores. There was also a significant reduction in chronic fatigue, and no significant complications from PTA occurred.
Take Home Pearls: MS patients diagnosed with CCSVI appear to show significant improvements in their clinical symptoms and quality of life after undergoing endovascular interventions to increase the flow of blood from the brain and spine back to the heart. The reductions in MS-related chronic fatigue following PTA seem to link it directly to CCSVI. Further follow-up investigations are warranted.
Comparing Stretch Grafts
The Particulars: Vascular grafts are used to bypass, replace, or maintain function in damaged, occluded, or diseased blood vessels. These grafts are available in small, medium, and large diameters. Autogenous grafts are harvested from the patient
Readings & Resources (click to view)
For more information on these items and other research that was presented at the 37th annual Veith Symposium as well as other information emerging from the meeting, go to www.veithsymposium.org.