nitinol and Vascular-Calcification

In the femoropopliteal segment, endovascular revascularization techniques have gained the role as a first line treatment strategy. Nitinol stent placement has improved the short- and mid-term primary patency rates in most lesion types and is therefore widely applied. Stenting has several shortcomings as in-stent restenosis, stent fractures and foreign material being left behind in the vessel. The concept of atherectomy is plaque debulking. This results in a potential reduction of inflation pressure requirements in angioplasty. Stent placement and consecutive in-stent restenosis may be avoided. In this non systematic literature review, the performance of different atherectomy techniques, such as direct atherectomy, orbital atherectomy, laser debulking and rotational atherectomy in the treatment of complex femoropopliteal lesions, including long lesions, moderately to heavily calcified lesions as well as occlusions and in-stent restenosis, has been analyzed.

Topics: Alloys; Atherectomy; Constriction, Pathologic; Equipment Failure; Femoral Artery; Graft Occlusion, Vascular; Humans; Inguinal Canal; Lasers, Excimer; Peripheral Vascular Diseases; Popliteal Artery; Severity of Illness Index; Stents; Treatment Outcome; Vascular Calcification; Vascular Patency

Excisional atherectomy alone or followed by stenting is considered an appropriate treatment strategy for patients with lifestyle-limiting claudication due to obstructive infra-inguinal peripheral arterial disease (Ramaiah et al., J Endovasc Ther 2006;13:592-6021). We present a case of a 69-year-old man with eccentric severely calcified disease of the superficial femoral artery (SFA) treated with excisional atherectomy followed by stenting with an interwoven nitinol stent. The procedure was complicated by extravascular stent migration associated with a contained rupture presenting 30 days after the intervention. The complication was successfully treated with a stent graft. Although rare, pseudoaneurysms have been reported at the site of prior atherectomy; however, this case is the first description of a contained rupture post atherectomy associated with erosion of a nitinol stent into an extra-luminal position. The mechanism and management of this complication are discussed.

Topics: Aged; Alloys; Angioplasty, Balloon; Atherectomy; Blood Vessel Prosthesis Implantation; Femoral Artery; Foreign-Body Migration; Humans; Male; Peripheral Arterial Disease; Prosthesis Design; Radiography; Rupture; Severity of Illness Index; Stents; Time Factors; Treatment Outcome; Ultrasonography, Doppler, Color; Ultrasonography, Interventional; Vascular Calcification; Vascular System Injuries

To determine the safety and efficacy of a new-generation nitinol stent with enhanced flexibility in arterial lesions in the superficial femoral artery (SFA) and proximal popliteal artery (PPA).. The Complete Self-Expanding (SE) Multicenter Trial (ClinicalTrials.gov identifier NCT00814970) enrolled 196 patients (124 men; mean age 68.7±10.5 years) from 28 centers in the United States and Europe. The patients presented with intermittent claudication (193/196) or ischemic rest pain (3/196) and were treated with nitinol stents for obstructive lesions of the SFA or PPA. Over a quarter of lesions (29.9%) were chronic total occlusions. The mean lesion length was 60.7 mm. Moderate to severe calcification was present in 91.0% of lesions.. A total of 225 stents were successfully implanted in 213 (99.5%) of 214 lesions. Acute lesion success (<30% residual stenosis) was achieved in 90.0%. There were no in-hospital major adverse events. Primary patency (defined as a peak systolic velocity ratio <2.0) at 12 months was 72.6%. Clinically-driven target lesion revascularization (TLR) was required in 8.4% of patients at 12 months. The mean ankle-brachial index increased from 0.7 at baseline to 0.9, and there was sustained improvement in the Rutherford category, with 83% of patients classified as Rutherford category 0 or 1 at 12-month follow-up. No stent fractures were detected through 12 months.. In this multicenter trial, primary implantation of a new-generation self-expanding nitinol stent in the SFA and PPA was associated with a low rate of TLR and sustained clinical benefit at 12 months without stent fracture.

Topics: Aged; Alloys; Angioplasty, Balloon; Ankle Brachial Index; Blood Flow Velocity; Chronic Disease; Europe; Female; Femoral Artery; Humans; Intermittent Claudication; Ischemia; Male; Middle Aged; Peripheral Arterial Disease; Popliteal Artery; Prospective Studies; Prosthesis Design; Radiography; Recovery of Function; Stents; Time Factors; Treatment Outcome; United States; Vascular Calcification; Vascular Patency

Topics: Alloys; Angioplasty, Balloon; Constriction, Pathologic; Critical Illness; Femoral Artery; Humans; Ischemia; Male; Middle Aged; Peripheral Arterial Disease; Popliteal Artery; Prosthesis Design; Stents; Treatment Outcome; Vascular Calcification; Vascular Patency

The aim of this study was to evaluate the safety and performance of the sinus-SuperFlex-635 self-expandable nitinol stent (Optimed GmbH) for the treatment of steno-occlusive lesions in the superficial femoral artery (SFA) and proximal popliteal artery (PPA).. The prospective, multicenter, observational HERO study recruited 117 eligible patients (83 men; mean age 69.4±9.7y) from 7 centers in Belgium.. A total of 129 stents were successfully deployed in 121 lesions in 117 patients (100%). The patients presented with symptomatic ≥50% stenosis or chronic total occlusion (CTO) (30.6%). Mean lesion length was 71.4±56.3 mm. Moderate to severe calcification was present in 82.6% of the lesions. Acute lesion success (<30% residual stenosis) was achieved in 96.0%. There were no in-hospital serious adverse events. Duplex ultrasound-driven primary patency at 12 months was recorded in 84 of 107 (78.5%) lesions. The overall target lesion revascularization (TLR) rate was 8.4% at 12 months; the target extremity revascularization (TER) rate was 4.7%. Clinical assessment at 12 months demonstrated improvement by at least 1 Rutherford class, without the need for TLR (i.e. primary sustained clinical improvement) in 83.9% of patients and with the need for TLR in 90.6% of patients (i.e. secondary sustained clinical improvement).. Based on the high primary patency, low stent fracture rate and significant clinical improvement, combined with refined stent design and long stent availability, the sinus-SuperFlex-635 self-expandable nitinol stent proves its value in the treatment of complex femoropopliteal lesions.

Topics: Aged; Aged, 80 and over; Alloys; Belgium; Endovascular Procedures; Female; Femoral Artery; Humans; Male; Middle Aged; Peripheral Arterial Disease; Popliteal Artery; Prospective Studies; Prosthesis Design; Registries; Self Expandable Metallic Stents; Time Factors; Treatment Outcome; Vascular Calcification; Vascular Patency

Percutaneous transluminal angioplasty (PTA) is a common procedure in patients with peripheral arterial disease (PAD) affecting the femoropopliteal segment (F-P). Biomimetic nitinol stents (Supera peripheral stent, SPS) and drug eluting stents (DES) were designed to improve the longevity of F-P PTA; however, their performance has not been compared in a pragmatic setting, taking atherosclerotic plaque characteristics into account.. Overall, 296 consecutive patients (mean age: 73 y, SD: 11 y, 65% male, 68% with chronic limb threatening ischaemia) who underwent F-P PTA using SPS or DES between 2013 and 2018 were identified from a prospectively maintained institutional database. Patient and plaque characteristics, including F-P plaque characterisation based on computed tomography, were collected; 121 case matched pairs were created using a propensity score based on patient and plaque data.. During the median two year follow up, 28% of the cohort (32% SPS vs. 24% DES, p = .07) developed target lesion restenosis (TLR) > 50%. Among the 121 case matched pairs of patients, those with SPS vs. DES were not significantly more likely to develop TLR >50% (31% vs. 27%, p = .34), or stent occlusion (13% vs. 12%, p = .85 - secondary patency rate 87% vs. 88%), have a major amputation (10% vs. 6%, p = .16), require re-intervention (14% vs. 9%, p = .12), or die (7% vs.4%, p = .31). Plaque calcification did not predict restenosis or occlusion in either stent group, both in the matched and non matched populations. Multivariable analysis adjusted for patient and plaque characteristics revealed that the main predictors of restenosis >50% at two years were female sex [odds ratio (OR): 2.05, p = .01], hypertension (OR: 2.10, p = .04) and previous F-P occlusion (OR: 1.35, p = .04).. Medium term results following F-P PTA with either SPS or DES are comparable, regardless of plaque calcification and patient characteristics.

Topics: Aged; Alloys; Angioplasty; Computed Tomography Angiography; Extremities; Female; Femoral Artery; Graft Occlusion, Vascular; Humans; Limb Salvage; Male; Outcome and Process Assessment, Health Care; Peripheral Arterial Disease; Plaque, Atherosclerotic; Popliteal Artery; Prognosis; Stents; Vascular Calcification; Vascular Patency

Information on performance of different stent platforms in endovascular revascularisation of femoropopliteal lesions is controversial and scarce.. Interwoven nitinol (INS, Supera) were compared with drug eluting (DES, Zilver PTx) stents with primary intervention for femoropopliteal lesions. The primary endpoint was time to clinically driven target lesion revascularisation (CD-TLR) within 12 months. Secondary endpoints were time to death, amputation and composite of death, amputation and CD-TLR. Due to the retrospective analysis, inverse probability treatment weighted (IPTW) Cox models were calculated to reach more similar patient populations with weights for the average treatment effect of the population. The two sensitivity analyses were propensity score matching and adjustment for covariates.. At 12 months, the cumulative incidence of CD-TLR in the INS group (13%) and DES group (18%) did not differ (HR 1.36, 95% CI 0.56-3.31). A significant interaction between stents used and grade of calcification was observed (p = .006). HR for CD-TLR was 6.4 (95% CI 1.3-32.5) in none to mildly calcified favouring INS, and 0.3 (95% CI 0.1-1.3) for moderate to severely calcified lesions favouring DES. Stent efficiency did not differ comparing treatment of popliteal lesions (HR 0.80; 95% CI 0.21-3.13). Sensitivity analyses confirmed the primary efficacy outcome for either adjusted (HR 1.16; 95% CI 0.51-2.62) or matched analysis (HR 1.35; 95% CI 0.50-3.62)). Interaction of stents with calcification grade was lost for adjusted (HR 0.28; 95% CI 0.06-1.19) and matched analysis (HR 0.53; 95% CI 0.10-2.91).. Both stents (INS and DES) showed comparable results regarding CD-TLR in femoropopliteal lesions, so that one stent could not be favoured over the other, even for calcified or popliteal artery lesions.

Topics: Aged; Aged, 80 and over; Alloys; Angiography, Digital Subtraction; Blood Vessel Prosthesis Implantation; Drug-Eluting Stents; Endovascular Procedures; Female; Femoral Artery; Humans; Male; Middle Aged; Paclitaxel; Peripheral Arterial Disease; Popliteal Artery; Prosthesis Design; Retrospective Studies; Self Expandable Metallic Stents; Treatment Outcome; Vascular Calcification

Topics: Aged, 80 and over; Alloys; Angiography; Femoral Artery; Humans; Male; Peripheral Vascular Diseases; Popliteal Artery; Prosthesis Design; Stents; Treatment Outcome; Vascular Calcification; Vascular Patency; Vascular Surgical Procedures

Coral reef aorta (CRA) is a rare condition, characterised by rock-hard calcification of the juxta-renal and supra-renal aorta with luminal encroachment causing significant stenosis of the aorta and its branches. It usually presents as resistant hypertension, renal dysfunction, mesenteric ischaemia, limb claudication or embolic manifestations. Although surgical thrombo-endarterectomy along with bypass graft to the affected visceral arteries remains the cornerstone of treatment, it is associated with considerable mortality and morbidity, especially in patients with pre-existing comorbidities. Here we report an elderly female of resistant hypertension, who had successful endovascular aortic stenting using a non-graft self-expanding stent. Her blood pressure dramatically improved following endovascular management. In comparison to the conventional surgical approach, endovascular stenting can be an alternative, less invasive approach in selected CRA patients.

Topics: Aged; Alloys; Aortic Diseases; Computed Tomography Angiography; Diabetic Angiopathies; Female; Humans; Hypertension; Stents; Tomography, X-Ray Computed; Treatment Outcome; Vascular Calcification