Coming in March, Vascular Disease Management will feature manuscripts by authors from a range of specialties. Carlos Bechara, MD, a vascular surgeon from Baylor College of Medicine, presents research studying lower-extremity bypass grafts. Jason Salsamendi, MD, an interventional radiologist from the University of Miami Miller School of Medicine, describes a case with his colleagues in which they used a technique that could aid interventions in various high-flow situations. And cardiologist Barry Weinstock, MD, from Orlando Regional Medical Center provides an update on contrast-induced nephropathy.
VASCULAR DISEASE MANAGEMENT
March 2014, Vol. 11, No. 3
Comparing Short and Midterm Infrainguinal Bypass Patency Rates Between Two ePTFE Prosthetic Grafts: Spiral Laminar Flow and Propaten
Carlos F. Bechara, MD
From Baylor College of Medicine, Houston, Texas.
Abstract: Objective: The ideal prosthetic graft to use for lower extremity bypass in patients with no vein conduit is yet to become available. Spiral laminar flow graft (SLFG) was designed to reduce turbulent flow at the distal anastomosis, hence reducing neointimal hyperplasia to improve graft patency. We examined our data for this type of graft and compared it to the Propaten graft by W.L. Gore (PG), which is another polytetrafluoroethylene (ePTFE) graft. Method: Single-center data were retrospectively reviewed for patients undergoing infrainguinal bypass using prosthetic grafts between January 2010 and January 2012. Kaplan-Meier analyses were performed to estimate primary and secondary patency rates for patients undergoing femoral to popliteal artery bypass (above and below the knee) as well as femoral to tibial artery bypass. The same was done for patients undergoing infrainguinal bypass using PG during the same time period. Results: 20 infrainguinal bypasses were performed using SLFG and 39 using PG were identified. A majority of the SLFG cases (14, 70%) were femoral to popliteal bypass (above and below the knee) and 6 cases (30%) were femoral to tibial artery bypass. Similar percentages were seen in the PG group. Statistically, the 6-, 12-, 18-, and 24-month primary and secondary patency rates for both grafts were the same regardless of the distal target artery. The primary patency for the popliteal artery (above and below knee) target group were 94%, 61 %, 61%, and 54% for the PG group, and 79%, 50%, 50%, and 50% for the SLFG group, respectively. The secondary patency rates were 94%, 66%, 66%, and 66% for the PG group and 86%, 57%, 57%, and 57% for the SLFG group, respectively. The 6-, 12-, and 18-month primary patency rates for the tibial artery bypass groups were 51%, 36%, and 37% for the PG group and 50%, 33%, and 17% for the SLFG group, respectively. The secondary patency rates were 54%, 34%, and 34% for the PG group and 60%, 40%, and 20% for the SLFG group, respectively. Conclusion: The design of the SLFG to mimic physiologic flow at the distal anastomosis is an interesting concept, but it has not translated into clinical benefit in comparison to another ePTFE graft in our series. Further research and modifications are needed to achieve the ideal graft for infrainguinal arterial bypass.
Flow-Arrest Interventional Repair of Renal Allograft Arteriovenous Fistula and Pseudoaneurysms
Jason Salsamendi, MD, Ami Vakharia, MD, and Adam N. Checkver, MD
From Jackson Memorial Hospital, Miami, Florida.
Abstract: As core biopsies of transplanted kidneys remain the “gold standard” for diagnosis of rejection, the risk of iatrogenic complications such as arteriovenous fistulas (AVF) and pseudoaneurysms remain quite real. This case report describes a case of a 59-year-old female with a suspected occult post-biopsy AVF and pseudoaneurysm which over 6 years became enlarged and multilobulated, discovered on routine follow-up imaging. As the patient because symptomatic with flash pulmonary edema, intervention was planned. Angiography demonstrated a complex network of pseudoaneurysms with high flow drainage to the renal venous system. As initial attempts at coil embolization failed due to high flow velocities, a proximal and distal balloon occlusion technique was implemented along with a combination of coils (Axium; Covidien) and glue (Trufil; DePuy) to obtain lasting resolution of the patient’s pathology with minimal risk of embolization material flowing distally. The authors theorize that this technique will facilitate similar results in various high-flow situations, as with transplant AV fistulas.
Contrast Induced Nephropathy: How to Avoid a Life of CIN
Barry S. Weinstock, MD
From Orlando Regional Medical Center, Orlando, Florida.
Abstract: Contrast-induced nephropathy, defined as a worsening or cessation of renal function following contrast administration remains an important issue with both clinical and economic impact. Contrast nephropathy occurs more frequently in “high risk” patients including those with pre-existing renal insufficiency, high volumes of contrast administration, advanced age, hypotension, congestive heart failure, diabetes and anemia. Multiple strategies have been studied to decrease the risk of contrast nephropathy. Current practice patterns often utilize approaches with little or no supporting data. These approaches are reviewed as well as newer strategies such as “targeted renal therapy” and expanded use of CO2 angiography.
First in Human Study for the Valiant Mona LSA Graft: An Interview With Frank R. Arko, MD
Frank R. Arko, MD
From the Sanger Heart and Vascular Institute at Carolinas Medical Center in Charlotte, N.C.
* Articles are subject to change at the editor’s discretion.