November 17, 2014 — VIVA Physicians, a not-for-profit organization in the field of vascular medicine and intervention, announced late-breaking clinical trial results VIVA 14, an annual multidisciplinary vascular education conference hosted in Las Vegas.
Below are summaries and results of all late-breaking clinical trial presentations:
Presented by Peter A. Schneider, M.D. There is critical need in urgent endovascular aneurysm repair (EVAR) for a bailout adjunct to treat proximal seal complications or address concerns in complex proximal neck anatomy. Reported herein are the first series of patients in urgent EVAR with EndoAnchors (Aptus Endosystems, Inc.), as captured through the ANCHOR global registry. Thirty-two centers enrolled 39 subjects classified as urgent over 18 months through July 2014. Among these, 36 (92%) aneurysms were intact and three (8%) were ruptured. Indications for EndoAnchor use in primary EVAR cases included prevention of late proximal neck complications in 23 patients (59%) and treatment of intraoperative type 1a endoleaks in eight (21%) patients. For revisions, indications included late type 1a endoleak treatment (four, 10%), type 1a endoleak with migration (three, 8%) or migration alone (one, 3%). Mean clinical follow-up was 14 ± 7 months. Treated endografts included Endurant (Medtronic Inc., 16, 41%), Excluder (Gore & Associates, 12, 31%), Zenith (Cook Medical, six, 15%), and other devices (five, 13%). Proximal necks averaged 27 ± 3 mm in diameter and 17 ± 11 mm in length; 27% were ? 10 mm. Neck angulation averaged 35 ± 16°; 27% of necks were conical. The total EndoAnchor deployment time was 15 ± 8 minutes. At completion angiography, 92% of subjects (37) were free from type 1a endoleaks. No patient developed rupture after repair. In the three patients treated after AAA rupture, there has been no reported recurring hemorrhage. There were no reinterventions or deaths due to proximal seal complications or EndoAnchors. Aneurysm-related reinterventions occurred in two patients (5%): one endograft limb stenosis and one type II endoleak. There was one aneurysm-related death (2.6%) from renal failure after repair of a symptomatic unruptured AAA. Core laboratory analysis of postoperative CT imaging (3-months mean follow-up) confirmed absence of type 1a endoleaks in all 16 patients with contrast studies. The excellent results in this cohort suggest EndoAnchors promise a useful adjunct in patients requiring urgent aneurysm repair.
Presented by Marianne Brodmann, M.D. The DISRUPT PAD study is a single-arm multicenter study of the safety and utility of Lithoplasty balloon catheters (Shockwave Medical) for treatment of calcified stenosis of the superficial femoral artery (SFA) and popliteal artery in 35 patients. The novel balloon-based technology utilizes integrated lithotripsy to disrupt both superficial and deep calcium, normalizing vessel wall compliance prior to low-pressure balloon dilatation. Enrolled candidates had intermittent claudication (Rutherford 2–4), ABI < 0.9, abnormal baseline functional studies, and radiographic evidence of moderate or severe calcification before angiography. Angiographic inclusion criteria stipulated de novo lesions up to 180 mm in length, stenosis > 70%, reference vessel diameter 3.3 to 7.2 mm, and moderate-to-severe bilateral calcification extending at least half the length of the lesion. Patients were treated with 60-mm balloons ranging in diameter from 3.5 to 7 mm at 0.5 mm increments. Primary safety results demonstrated no major adverse events and an excellent safety profile. Primary efficacy results demonstrated 100% success defined as ability to achieve < 50% residual stenosis using Lithoplasty +/- adjunctive PTA. Device success was 87%, defined as ability to achieve < 50% residual stenosis using Lithoplasty alone. Importantly, an average residual stenosis of 23% (initial 76%), with no difference in the ability to dilate lesions between moderate (36%) and severely (64%) calcified lesions, was noted. Follow-up evaluations include clinical exam and core lab adjudicated duplex ultrasound at 30 days and 6 months. Thirty-day patency assessed by duplex ultrasound was 100%. Calcified vascular lesions remain a major impediment to modern percutaneous therapy for vascular disease. The results of this trial provide a perspective on the utility of Lithoplasty balloon catheters for an unmet clinical need in a large subset of patients with peripheral artery disease.
Presented by Peter Faries, M.D. DURABILITY Iliac is a prospective, multicenter, nonrandomized study designed to confirm the safety and effectiveness of primary stenting using the EverFlex and Protégé GPS self-expanding stent systems (Covidien) for the treatment of stenotic, restenotic or occluded lesions in the common and external iliac arteries. The study enrolled 75 patients (mean age, 62.3 years; 65.3% male) at 15 centers in the United States and Europe. The primary endpoint was the rate of major adverse events (MAE) within nine months of the procedure, defined as a composite of periprocedural death, in-hospital myocardial infarction (MI), clinically driven target lesion revascularization (CD-TLR), and amputation of the treated limb. Secondary outcomes included device success (defined as the ability to deploy the stent as intended at the treatment site), 30-day MAE rate, nine-month primary patency rate as determined by duplex ultrasound (peak systolic velocity ratio ? 2.4, with no clinically driven reintervention within the stented segment), change in ankle-brachial index (ABI), and functional assessment based on walking impairment questionnaire (WIQ) scores at 30 days and nine months compared to baseline. Device success was achieved for all implanted stents. There were no MAE's at 30 days. At nine months, MAE rate was 1.3% (one patient with CD-TLR), Kaplan-Meier primary patency was 95.8%, and freedom from CD-TLR was 98.6%. There were significant improvements in ABI and WIQ scores at 30 days and 9 months when compared to baseline. These data confirm the safety and effectiveness of the EverFlex and Protégé GPS stents in treating symptomatic iliac artery disease.
Endurant 4-Year Results
Presented by Edward Woo, M.D. This was a prospective, single-arm, multicenter trial conducted at 26 sites in the United States to evaluate the Endurant stent graft system (Medtronic, Inc.) for the treatment of abdominal aortic aneurysms (AAAs). From April 2008 to May 2009, 150 patients with AAA were treated with the Endurant bifurcated stent graft. The main inclusion criteria were an AAA diameter > 5 cm, proximal neck length ? 10 mm, bilateral iliac fixation length ? 15 mm, and a neck angulation of ? 60°. A clinical events committee adjudicated all adverse events except blood loss, and a core laboratory reviewed all imaging. The primary safety endpoint was freedom from major adverse events at 30 days, and the primary effectiveness endpoint was successful aneurysm treatment at 12 months. One hundred forty-nine patients (99.3%) had a successful stent graft implant, and 83.3% were under general anesthesia. One failure was due to inability to cannulate the contralateral gate. One patient developed a neck rupture during the procedure, but was still treated successfully. Patients were predominantly male (91.3%), elderly (mean age, 73.1 years), and had significant comorbidities. Mean estimated blood loss was 185 mL (range, 0–1,450 mL), with blood transfusion required in one patient. Average hospital stay was 2.1 days. Through 48 months of follow-up, there were no migrations, ruptures or conversions. There was one type 1 endoleak and no type 3 endoleaks reported at 48 months. There were low rates of AAA sac enlargement and secondary procedures. Midterm results of the Endurant pivotal trial are encouraging and suggest a safe and effective device for the treatment of AAAs.
GORE TAG Thoracic Branch Zone 2 Feasibility Study
Presented by Michael Dake, M.D. This is a nonrandomized, multicenter, prospective feasibility study conducted at up to six clinical investigative sites in the United States. The primary objective of the study is to assess the feasibility of the Gore TAG thoracic branch endoprosthesis (TBE) to treat aneurysms involving the proximal descending thoracic aorta. A minimum of 20 and up to a total of 40 subjects with aneurysms involving the proximal descending thoracic aorta that require treatment will be enrolled into the study. Enrolled subjects will be followed after the initial treatment for five years or until termination of the trial. The Gore TAG TBE has an aortic component, a side branch component and an optional aortic extender. An additional investigational accessory, the Gore DrySeal side branch introducer sheath, is used in conjunction with the TBE. Subjects may be enrolled into the clinical study provided all inclusion and no exclusion criteria are met. Subjects will be evaluated through hospital discharge and return for follow-up visits at 1, 6, 12, 24, 36, 48, and 60 months after treatment. The primary endpoints of the study will be successful access and deployment of the branched TAG device and procedural side branch patency assessed by angiography at the conclusion of the endovascular procedure. The secondary endpoints include one-month side branch primary patency and one-month device-related endoleaks, both assessed by an independent core lab. The primary endpoints provide a measurement of the feasibility of implantation of the Gore TAG TBE. Preliminary site-reported data from the first nine subjects reveal 100% access and deployment success. Among those subjects with follow-up, there are no deaths, no neurological events, and 100% side branch component patency.
Presented by Eamon Dolan, M.D. There is a high prevalence of hypertension, particularly in older adults. Having an elevated blood pressure is the leading cause of both death and disability worldwide. Patients are considered to have resistant hypertension when they are compliant with three or more antihypertensive medications but fail to achieve blood pressure treatment targets. There are many challenges in the management of hypertension, such as patient compliance and the nonavailability of new potent pharmacotherapies. In recent years, there has been a move to overcome these limitations with the development of device-based treatment of resistant hypertension. The Rox Medical CONTROL-HTN study is a randomized study evaluating the blood pressure-lowering effect of the Rox Coupler in resistant hypertensive patients across European study sites. The procedure involves the creation of a fixed 4-mm-diameter arteriovenous anastomosis between the external iliac vein and artery through the placement of a nitinol coupler under angiographic guidance. In 83 randomized patients, there was a significant reduction in office blood pressure among those who underwent the procedure. This was also the case for ambulatory blood pressure tested over 24 hours. Results demonstrate a cushioning of blood pressure effect that may have benefits beyond blood pressure lowering alone. There is a reduction in the variability of both systolic and diastolic blood pressure, particularly in the daytime period. There is also a reduction in maximum blood pressure, or the peak blood pressure, during the 24-hour period. Studies have shown this buffering effect may potentially reduce hypertensive damage brought about by extremes of blood pressure.
Endovascular Aortic Repair in Acute Type B Aortic Dissection: Results from the Valiant Captivia United States IDE Study
Presented by Ali Azizzadeh, M.D. An acute type B aortic dissection complicated by malperfusion or contained rupture carries a high risk of spontaneous death. We report 30-day and 12-month results of endovascular treatment with the Valiant Captivia thoracic stent graft (Medtronic, Inc.) in these patients. The Medtronic DISSECTION trial was a multicenter, prospective, nonrandomized, pivotal trial with five-year follow-up. Fifty patients were enrolled. Rupture was present in 20% and malperfusion in 86%. Successful delivery, deployment, and coverage of the primary entry tear were achieved in 100% of procedures. Two patients underwent open repair at 5 and 56 days post-procedure after retrograde aortic dissections (4%). Freedom from all-cause mortality was 92% at 30 days and 86% at 12 months. There was an acceptable rate of adverse events through 12 months: 6% CVA, 4% paraplegia and 2% SCI. Four patients underwent secondary endovascular procedures—three related to dissection using endograft extension and one not related to dissection using an LSA plug. There was no incidence of stent graft collapse or loss of integrity. Through 12 months, true lumen diameter over the stented region (or endograft segment) remained stable or increased in 94.1%; false lumen diameter remained stable or decreased in 82.4%; and the false lumen was partially or completely thrombosed in 79.4% of patients. Initial results of the Valiant Captivia thoracic stent graft in the treatment of acute type B aortic dissection are encouraging. Longer-term outcomes are needed to assess the durability of thoracic endovascular aortic repair for this indication.
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