Establishing a Critical Limb Ischemia Outpatient Center: Separating Facts from Myth.

Critical Limb Ischemia or chronic limb-threatening ischemia represents the end stage of peripheral artery disease where arterial flow is compromised to the lower extremities and risk of limb loss may become imminent. Revascularization of lower extremities is one of the cornerstones of limb salvage and amputation prevention. Establishing centers of high quality CLI therapy requires creating different foundational pillars in order to be successful. This article discusses critical limb ischemia center creation from the perspective of critical limb ischemia therapists working in an outpatient setting.

Peripheral Arterial Disease Treatment in the Non-Hospital Setting.

Treatment of peripheral artery disease (PAD) has undergone a progressive shift toward less invasive, endovascular options within the last three decades. For PAD patients, the benefits of this shift are numerous and include less periprocedural pain, decreased blood loss, shorter recovery times, and fewer missed workdays. Commonly, patient-reported outcomes are very positive with this "endovascular first" strategy and the number of open surgical procedures for various stages of PAD has declined steadily over the last 20 years. Coincident with this trend is the move toward "ambulatory" lower extremity arterial intervention (LEAI) in the hospital outpatient "same-day" department. The next logical extension was then performing LEAI in a true physician office-based lab (OBL), ambulatory surgical center (ASC), or "non-hospital setting." This article examines these trends and the concept that the OBL/ASC provides a safe, alternative site of service for PAD patients requiring LEAI.

Percutaneous Deep Venous Arterialization: Treatment of Patients with End-Stage Plantar Disease.

Background: Percutaneous deep venous arterialization (pDVA) is a minimally invasive technique connecting the tibial arteries below the knee to the tibial venous system into plantar venous circulation to deliver oxygenated blood to otherwise nonperfused foot. This study demonstrated outcomes of pDVA with commercially available equipment and described single-center experience on pDVA for critical limb-threatening ischemia patients with small artery diseases and end-stage plantar disease (ESPD) who were deemed no-option cases. Methods: A single-center retrospective review was performed on patients who underwent pDVA. Primary end points were successful establishment of tibial vein flow with venous pedal loop, rate of major amputation, and major adverse events over 6 months. Secondary end points were primary and secondary patency rates, minor amputation rates, and wound healing over 6 months. Results: Forty-two patients with ESPD underwent pDVA. Risk factors identified were hypertension (92.8%), hyperlipidemia (85.7%), diabetes (78.6%), tobacco abuse (42.9%), and chronic kidney disease ≥ stage 3 (42.8%). Three patients were categorized as Rutherford Class 4, 14 patients Class 5, and 25 patients (59.5%) Class 6. Of 42 procedures, 33 (78.6%) were deemed successful. Amputation-free survival at 6 months was reported in 25 patients (60.9%); 16 patients (38.1%) reported minor amputations. Wound healing rate reported at 6 months was 23.8%. Conclusions: This is one of the largest case series to date with real-world no-option patients undergoing pDVA. pDVA seems a reasonable option for limb salvage in patients with ESPD where traditional arterial revascularization is not feasible. Identifying criteria for patient selection and advanced wound care is important to ensure clinical success. Additional research is required to establish diagnostic guidelines for patients being evaluated for pDVA.

Evaluation and treatment of patients with lower extremity peripheral artery disease: consensus definitions from Peripheral Academic Research Consortium (PARC).

The lack of consistent definitions and nomenclature across clinical trials of novel devices, drugs, or biologics poses a significant barrier to accrual of knowledge in and across peripheral artery disease therapies and technologies. Recognizing this problem, the Peripheral Academic Research Consortium, together with the U.S. Food and Drug Administration and the Japanese Pharmaceuticals and Medical Devices Agency, has developed a series of pragmatic consensus definitions for patients being treated for peripheral artery disease affecting the lower extremities. These consensus definitions include the clinical presentation, anatomic depiction, interventional outcomes, surrogate imaging and physiological follow-up, and clinical outcomes of patients with lower-extremity peripheral artery disease. Consistent application of these definitions in clinical trials evaluating novel revascularization technologies should result in more efficient regulatory evaluation and best practice guidelines to inform clinical decisions in patients with lower extremity peripheral artery disease.

Tibiopedal access for lower extremity arterial intervention: when to use and how to perform.

Tibiopedal artery access is being used with increasing frequency as an alternative access to facilitate procedural success in lower extremity arterial intervention. This technique is usually employed in the setting of critical limb ischemia and tibial artery intervention, but it may offer potential practical advantages for popliteal artery and even superficial femoral artery intervention in unique situations. As in all cases of lower extremity arterial intervention, consideration of access is important not only for initial approach to any obstructing lesion but also for exit strategy. The dorsalis pedis artery and posterior tibial artery can be readily accessed if necessary owing to their relatively superficial position in the foot or the ankle, yet their normal diameter and the presence of significant calcification (a common finding in patients with tibial occlusive disease and critical limb ischemia) can pose difficulties as well. In addition, the peroneal artery in the lower leg can be accessed percutaneously; however, its size and depth may present additional challenges. Meticulous attention to detail is paramount in avoiding complications in what may be the only distal vessel supplying the foot. This article describes common techniques in using tibiopedal artery access as a means of alternative access for successful infrainguinal intervention.

A randomized, controlled pilot study of autologous CD34+ cell therapy for critical limb ischemia.

BACKGROUND: Critical limb ischemia portends a risk of major amputation of 25% to 35% within 1 year of diagnosis. Preclinical studies provide evidence that intramuscular injection of autologous CD34+ cells improves limb perfusion and reduces amputation risk. In this randomized, double-blind, placebo-controlled pilot study, we evaluated the safety and efficacy of intramuscular injections of autologous CD34+ cells in subjects with moderate or high-risk critical limb ischemia, who were poor or noncandidates for surgical or percutaneous revascularization (ACT34-CLI). METHODS AND RESULTS: Twenty-eight critical limb ischemia subjects were randomized and treated: 7 to 1 × 10(5) (low-dose) and 9 to 1 × 10(6) (high-dose) autologous CD34+ cells/kg; and 12 to placebo (control). Intramuscular injections were distributed into 8 sites within the ischemic lower extremity. At 6 months postinjection, 67% of control subjects experienced a major or minor amputation versus 43% of low-dose and 22% of high-dose cell-treated subjects (P=0.137). This trend continued at 12 months, with 75% of control subjects experiencing any amputation versus 43% of low-dose and 22% of high-dose cell-treated subjects (P=0.058). Amputation incidence was lower in the combined cell-treated groups compared with control group (6 months: P=0.125; 12 months: P=0.054), with the low-dose and high-dose groups individually showing trends toward improved amputation-free survival at 6 months and 12 months. No adverse safety signal was associated with cell administration. CONCLUSIONS: This study provides evidence that intramuscular administration of autologous CD34+ cells was safe in this patient population. Favorable trends toward reduced amputation rates in cell-treated versus control subjects were observed. These findings warrant further exploration in later-phase clinical trials. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00616980.

Safety and performance of targeted renal therapy: the Be-RITe! Registry.

PURPOSE: To evaluate the safety and patterns of use of targeted renal therapy (TRT) with the Benephit system. TRT, the delivery of therapeutic agents directly to the kidneys by renal arterial infusion, has the advantage of providing a higher local effective dose with potentially greater renal effects, while limiting systemic adverse effects due to renal first-pass elimination. METHODS: The Benephit System Renal Infusion Therapy (Be-RITe!) Multicenter Registry was a post-market registry following patients treated using the Benephit systems for TRT. The registry enrolled 501 patients (332 men; mean age 72.2+/-9.5 years) at high risk for contrast-induced nephropathy (CIN) during coronary or peripheral angiography/intervention or cardiovascular surgery. The Mehran score was used to compare the actual to predicted incidence of CIN within 48 hours post procedure. RESULTS: Bilateral renal artery cannulation was successful in 94.2%, with a mean cannulation time of 2.0 minutes. Either fenoldopam mesylate, sodium bicarbonate, alprostadil, or B-type natriuretic peptide (BNP) was infused for 184+/-212 minutes. Mean creatinine levels did not change significantly (baseline, 24, and 48 hours post procedure: 1.95, 1.99, and 1.98 mg/dL, respectively; p = NS). In 285 patients who received TRT with fenoldopam and were followed for at least 48 hours, the incidence of CIN was 71% lower than predicted (8.1% actual CIN versus 28.0% predicted; p<0.0001). Only 4 (1.4%) patients required dialysis (versus the 2.6% predicted rate, p = NS). CONCLUSION: The Benephit system and TRT during coronary and endovascular procedures in patients at high risk for renal failure is simple to use and safe. With the infusion of intrarenal fenoldopam, the incidence of CIN was significantly lower than predicted by risk score calculations.

Tibial intervention for critical limb ischemia.

Diagnosis and treatment of critical limb ischemia (CLI) is increasingly important as the average age of the world population and the incidence of diabetes and metabolic syndrome increases. Fortunately, most patients will not progress to this stage of peripheral arterial disease, yet if left untreated, there is a high risk of future cardiovascular events. At the point of ischemic rest pain or tissue loss, there are significant implications for morbidity and mortality. There is a high prevalence of multisegment occlusive disease in the CLI patient with the infrapopliteal vessels frequently involved. Revascularization of the affected limb is of utmost importance as the prospects of wound healing and relief of ischemic rest pain are poor without reestablishing continuous flow to the distal extremity. With the advent of endovascular devices designed to treat this vexing problem, the ability to successfully treat this difficult patient population with less procedural morbidity has been greatly enhanced.