nitinol and Coronary-Stenosis

The Cappella Sideguard (CS) sidebranch stent is a self-expanding, thin-strut, nitinol device with anatomic flaring at the sidebranch ostium designed to treat bifurcation lesions.. To evaluate the mechanism of long-term lumen patency of the novel, self-expanding CS sidebranch stent compared with a balloon-expandable stent in the main vessel.. We performed intravascular ultrasound postintervention and at follow-up in 24 CS stents and in 28 balloon-expandable drug-eluting stents deployed in the corresponding main vessel. Thirteen patients also had optical coherence tomography (OCT) at follow-up to evaluate neointimal hyperplasia and strut coverage.. CS stent area at the sidebranch carina increased significantly from 3.8 ± 1.2 mm(2) postintervention to 4.6 ± 1.2 mm(2) at follow-up (P < 0.001), resulting in no change in lumen area (3.8 ± 1.2 mm(2) to 3.7 ± 1.2 mm(2) , P = 0.72) despite a neointimal area at follow-up of 0.9 ± 0.8 mm(2) . Volumetric changes were similar, and the distribution of neointimal hyperplasia peaked 1-2 mm distal to the carina. Change of lumen volume inversely correlated to the neointimal volume (R = -0.48, P < 0.001), but correlated positively to the change in stent volume (R = 0.52, P < 0.0001). By OCT, most CS struts were covered (100% [98.9, 100]) at the bifurcation site, whereas 61% of floating DES struts that crossed the sidebranch were covered by smooth tissue with a similar texture compared with neointima.. Although neointimal hyperplasia accumulates within the CS stent mainly 1-2 mm distal to the carina, the self-expanding CS stent may be effective in maintaining an adequate patency in the sidebranch by continued stent expansion noted at follow-up.

Topics: Aged; Alloys; Analysis of Variance; Angioplasty, Balloon, Coronary; Chi-Square Distribution; Coronary Angiography; Coronary Stenosis; Drug-Eluting Stents; Equipment Design; Female; Follow-Up Studies; Humans; Male; Middle Aged; Monitoring, Physiologic; Neointima; Pliability; Prospective Studies; Prosthesis Design; Statistics, Nonparametric; Tomography, Optical Coherence; Ultrasonography, Interventional; Vascular Patency

The aim of the pilot SECRITT trial was to evaluate the safety and feasibility of sealing the high risk IVUS and optical coherence tomography-derived thin cap fibroatheroma (TCFA), with a dedicated nitinol self-expanding vShield device.. After screening with angiography, fractional flow reserve (FFR), intravascular ultrasound virtual histology (IVUS-VH) and optical coherence tomography (OCT), 23 patients met enrolment criteria (presence of non-obstructive VH-derived TCFA lesion with thin cap on OCT) and were randomised to vShield (n=13) versus medical therapy (n=10). In the shielded group, baseline percent diameter stenosis was 33.2±13.5%, FFR was 0.93±0.06. At six-month follow-up in shielded patients percent diameter stenosis further decreased to 18.7±16.9% and FFR remained the same 0.93±0.05. Average late loss was 0.24±0.13 mm. Average baseline fibrous cap thickness was 48±12 µm. After shield placement at six-month follow-up neo-cap formation was observed with average cap thickness of 201±168 µm. There were no dissections after shield placement and no plaque ruptures. In addition, mean stent area of 8.76±2.16 mm2 increased to 9.45±2.30 mm2, that is by 9% at six-month follow-up. The number of malapposed struts decreased from 10.7% to 7.6% and the number of uncovered struts at six months was 8.1%. There were no device-related major adverse cardiovascular events (MACE) events at six-month follow-up.. High risk plaque passivation and sealing with a vShield self-expanding nitinol device appears feasible and safe. A long-term larger randomised study with streamlined screening criteria is needed to evaluate the efficacy of this approach over medical therapy.

Topics: Aged; Aged, 80 and over; Alloys; Coronary Angiography; Coronary Artery Disease; Coronary Stenosis; Feasibility Studies; Female; Fractional Flow Reserve, Myocardial; Humans; Longitudinal Studies; Male; Middle Aged; Percutaneous Coronary Intervention; Pilot Projects; Plaque, Atherosclerotic; Stents; Tomography, Optical Coherence; Ultrasonography, Interventional

To assess the efficacy of the AXXESS stent on the treatment of left main coronary artery (LMCA) bifurcation lesions using IVUS.. The treatment of LMCA bifurcation lesions remains challenging even with the use of drug-eluting stents. The AXXESS system is a biolimus A9-eluting self-expanding stent, dedicated to the treatment of bifurcation lesions.. Data were obtained from the AXXENT trial, a prospective, single-arm, multicenter study designed to evaluate the efficacy of the AXXESS stent on the treatment of LMCA bifurcation lesions. IVUS was available in 26 cases at 6-months follow-up. Volumetric and cross-sectional analyses within the AXXESS stent, and cross-sectional analyses at the ostia of left anterior descending (LAD) and left circumflex coronary arteries (LCX) were performed.. Within the AXXESS stent, percent neointimal volume obstruction was (3.0 +/- 4.1)% with a minimal lumen area of 10.3 +/- 2.6 mm(2). AXXESS stent volume showed an 12.4% increase at follow-up compared with postprocedure (P = 0.04). Lumen area was significantly smaller in the LCX ostium compared with the LAD ostium at follow-up (3.6 +/- 1.3 mm(2) vs. 5.5 +/- 2.0 mm(2), P = 0.0112). There was greater neointimal formation in the LCX ostium compared with the LAD ostium (1.37 +/- 1.20 mm(2) vs. 0.30 +/- 0.36 mm(2), P = 0.0003).. The AXXESS stent in the LMCA showed enlargement through 6-months follow-up and significant neointimal suppression. Greater neointimal formation and relatively inadequate stent expansion may contribute to luminal narrowing in the LCX ostium.

Topics: Aged; Alloys; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Cell Proliferation; Coronary Angiography; Coronary Restenosis; Coronary Stenosis; Coronary Vessels; Drug-Eluting Stents; Europe; Female; Humans; Male; Middle Aged; Prospective Studies; Prosthesis Design; Sirolimus; Stents; Time Factors; Treatment Outcome; Tunica Intima; Ultrasonography, Interventional; United States

Coronary obstruction is a rare but potentially fatal complication of transcatheter aortic valve replacement (TAVR). It can result from native leaflet or stent frame obstruction of the coronary ostia. There are reports detailing the difficulty of percutaneous coronary intervention following TAVR, but none that describe a periscope approach to access the left main ostia in the presence of a braided nitinol frame. This report describes an alternative approach to access a coronary artery when the valve stent struts are prohibitive to equipment delivery.

Topics: Aged, 80 and over; Alloys; Angioplasty, Balloon, Coronary; Aortic Valve Stenosis; Coronary Stenosis; Female; Heart Valve Prosthesis; Humans; Prosthesis Design; Severity of Illness Index; Stents; Transcatheter Aortic Valve Replacement; Treatment Outcome

Topics: Alloys; Antibiotics, Antineoplastic; Coronary Stenosis; Drug-Eluting Stents; Humans; Percutaneous Coronary Intervention; Self Expandable Metallic Stents; Sirolimus; Treatment Outcome

Topics: Alloys; Antineoplastic Agents; Coronary Stenosis; Drug-Eluting Stents; Humans; Paclitaxel; Percutaneous Coronary Intervention; Sirolimus; Stents; Treatment Outcome

Because of its low profile and biologically inert behavior, thin film nitinol (TFN) is ideally suited for use in construction of endovascular devices. We have developed a surface treatment for TFN designed to minimize platelet adhesion by creating a superhydrophilic surface. The hemocompatibility of expanded polytetrafluorethylene (ePTFE), untreated thin film nitinol (UTFN), and a surface treated superhydrophilic thin film nitinol (STFN) was compared using an in vitro circulation model with whole blood under flow conditions simulating a moderate arterial stenosis. Scanning electron microscopy analysis showed increased thrombus on ePTFE as compared to UTFN or STFN. Total blood product deposition was 6.3 ± 0.8 mg/cm(2) for ePTFE, 4.5 ± 2.3 mg/cm(2) for UTFN, and 2.9 ± 0.4 mg/cm(2) for STFN (n = 12, p < 0.01). ELISA assay for fibrin showed 326 ± 42 μg/cm(2) for ePTFE, 45.6 ± 7.4 μg/cm(2) for UTFN, and 194 ± 25 μg/cm(2) for STFN (n = 12, p < 0.01). Platelet deposition measured by fluorescent intensity was 79,000 20,000 AU/mm(2) for ePTFE, 810 ± 190 AU/mm(2) for UTFN, and 1600 ± 25 AU/mm(2) for STFN (n = 10, p < 0.01). Mass spectrometry demonstrated a larger number of proteins on ePTFE as compared to either thin film. UTFN and STFN appear to attract significantly less thrombus than ePTFE. Given TFN's low profile and our previously demonstrated ability to place TFN covered stents in vivo, it is an excellent candidate for use in next-generation endovascular stents grafts.

Topics: Alloys; Blood Platelets; Blood Proteins; Coronary Stenosis; Fibrin; Hemorheology; Humans; Mass Spectrometry; Materials Testing; Microscopy, Electron, Scanning; Microscopy, Fluorescence; Thrombosis

Topics: Alloys; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Coronary Restenosis; Coronary Stenosis; Drug-Eluting Stents; Humans; Prosthesis Design; Sirolimus; Stents; Treatment Outcome; Ultrasonography, Interventional

A 56 year-old woman underwent percutaneous coronary intervention for a lesion in a small mid-left anterior descending coronary artery (reference vessel diameter by quantitative coronary angiography: 2.11 mm) with a novel drug-eluting stent specifically designed for small vessels, the CardioMind Sparrow stent delivery system. This is a self-expandable sirolimus-eluting nitinol stent directly mounted into a 0.014-inch coronary guidewire. The stent has a very thin strut thickness (67 micron), limiting its radiopacity. A specific X-ray stent-enhancing visualization technique, "StentBoost", allowed clear visualization and understanding of the steps needed for an appropriate release and deployment of the aforementioned stent.

Topics: Alloys; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Coronary Angiography; Coronary Stenosis; Drug-Eluting Stents; Female; Humans; Middle Aged; Prosthesis Design; Radiographic Image Enhancement; Radiography, Interventional; Sirolimus; Treatment Outcome

A 62-year-old man underwent percutaneous coronary intervention of a bifurcation lesion (Medina type 010) involving the mid-left anterior descending coronary artery and an important first diagonal branch with a novel stent specifically designed for bifurcations, the Stentys coronary bifurcation system. This is a self-expanding nitinol stent, with Z-shaped struts linked by interconnections that can be disconnected (in prespecified points every 1.5 mm all around the circumference and the length of the stent) at the level of the ostium of the side branch, simply by inflating an angioplasty balloon tracked to the ostium of the side branch, through the stent struts. The steps required for deployment of the stent and the final result obtained were evaluated by intravascular ultrasound examination and StentBoost Subtract, a specific X-ray stent-enhancing visualization technique.

Topics: Alloys; Angioplasty, Balloon, Coronary; Cineangiography; Coronary Angiography; Coronary Stenosis; Humans; Male; Middle Aged; Predictive Value of Tests; Prosthesis Design; Radiographic Image Interpretation, Computer-Assisted; Radiography, Interventional; Stents; Treatment Outcome; Ultrasonography, Interventional

The stenting of aorto-ostial lesions in the native coronary circulation, renal arteries, and saphenous vein grafts is technically challenging.. We report the first in the world use of the Ostial Protrade mark, a novel nitinol-based device, utilized in conjunction with standard stenting techniques to assist in the precise placement of stents for the treatment of aorto-ostial lesions.. The Ostial Pro, is a relatively simple nitinol device that is positioned within the guiding catheter. It has distal, self-expanding legs that are advanced just distal to the tip of the guiding catheter after the ostial lesion has been crossed with the coronary guidewire and stent delivery system. The expanded nitinol legs prevent the entry of the guiding catheter into the target vessel, mark the plane of the aortic wall, and align the tip of the guide with the aorto-ostial plane. We report the successful and precise placement of stents in the aorto-ostial location in two patients with; (1) a saphenous vein graft ostial lesion and (2) a right coronary ostial lesion, using the new Ostial Pro stent positioning device. Excellent stent positioning, relative to the aorto-ostial plane, was confirmed by angiography and long axis intravascular ultrasound in both cases.. (1) The Ostial Pro is a new, commercially available (FDA cleared), nitinol device that is simple to use and appears effective in allowing the precise placement of stent(s) at the aorto-ostial location. (2) This approach may provide a simple and effective means to assure accurate stent placement in these difficult to treat lesions.

Topics: Aged; Alloys; Angioplasty, Balloon, Coronary; Cardiac Catheterization; Coronary Artery Bypass; Coronary Restenosis; Coronary Stenosis; Drug-Eluting Stents; Equipment Design; Equipment Safety; Follow-Up Studies; Graft Occlusion, Vascular; Humans; Male; Middle Aged; Radiography; Risk Assessment; Sensitivity and Specificity; Treatment Outcome

Subintimal angioplasty is a simple and safe alternative to conventional intraluminal angioplasty for the recanalization of diffuse long femoropopliteal occlusions. However, long-term patency rates are unsatisfactory despite the high initial technical success rates. Two cases of occluded left superficial femoral arteries are presented in which subintimal angioplasty with proximal stent implantation was successfully performed. Self-expanding nitinol stents were placed at the proximal part of subintimal plane to maintain good inflow. In both cases, follow-up angiogram at 6 months demonstrated patent stents with good antegrade flow.

Topics: Aged; Alloys; Angioplasty, Balloon; Arterial Occlusive Diseases; Blood Vessel Prosthesis Implantation; Coated Materials, Biocompatible; Coronary Stenosis; Femoral Artery; Humans; Intermittent Claudication; Male; Middle Aged; Popliteal Artery; Radiography; Stents; Tunica Intima

Topics: Alloys; Angioplasty, Balloon; Arterial Occlusive Diseases; Blood Vessel Prosthesis Implantation; Coated Materials, Biocompatible; Coronary Stenosis; Femoral Artery; Humans; Intermittent Claudication; Popliteal Artery; Radiography; Stents; Tunica Intima