nitinol and Cardiovascular-Diseases

It remains unclear whether cilostazol, which has been shown to improve the clinical outcomes of endovascular therapy for femoropopliteal lesions, also reduces angiographic restenosis.. The Sufficient Treatment of Peripheral Intervention by Cilostazol (STOP-IC) study investigated whether cilostazol reduces the 12-month angiographic restenosis rate after percutaneous transluminal angioplasty with provisional nitinol stenting for femoropopliteal lesions. Two hundred patients with femoropopliteal lesions treated from March 2009 to April 2011 at 13 cardiovascular centers were randomly assigned 1:1 to receive oral aspirin with or without cilostazol. The primary end point was 12-month angiographic restenosis rate. Secondary end points were the restenosis rate on duplex ultrasound, the rate of major adverse cardiac events, and target lesion event-free survival. Researchers evaluated all follow-up data and assessed the end points in a blinded fashion. The mean lesion length and reference vessel diameter at the treated segment were 128±86 mm and 5.4±1.4 mm, respectively. The frequency of stent used was similar between groups (88% versus 90% in the cilostazol and noncilostazol group, respectively, P=0.82). During the 12-month follow-up period, 11 patients died and 152 patients (80%) had evaluable angiographic data at 12 months. The angiographic restenosis rate at 12 months was 20% (15/75) in the cilostazol group versus 49% (38/77) in the noncilostazol group (P=0.0001) by intention-to-treat analysis. The cilostazol group also had a significantly higher event-free survival at 12 months (83% versus 71%, P=0.02), although cardiovascular event rates were similar in both groups.. Cilostazol reduced angiographic restenosis after percutaneous transluminal angioplasty with provisional nitinol stenting for femoropopliteal lesions.. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00912756; and URL: https://www.umin.ac.jp. Unique identifier: UMIN000002091.

Topics: Aged; Aged, 80 and over; Alloys; Angioplasty; Aspirin; Cardiovascular Diseases; Cilostazol; Constriction, Pathologic; Disease-Free Survival; Drug Therapy, Combination; Female; Femoral Artery; Follow-Up Studies; Humans; Male; Middle Aged; Peripheral Arterial Disease; Platelet Aggregation Inhibitors; Popliteal Artery; Prospective Studies; Radiography; Recurrence; Single-Blind Method; Stents; Tetrazoles; Ultrasonography; Vasodilator Agents

Many alloys used in cardiovascular device applications contain high levels of nickel, which if released in sufficient quantities, can lead to adverse health effects. While nickel release from these devices is typically characterized through the use of in-vitro immersion tests, it is unclear if the rate at which nickel is released from a device during in-vitro testing is representative of the release rate following implantation in the body. To address this uncertainty, we have developed a novel biokinetic model that combines a traditional toxicokinetic compartment model with a physics-based model to estimate nickel release from an implanted device. This model links the rate of in-vitro nickel release from a cardiovascular device to serum nickel concentrations, an easily measured endpoint, to estimate the rate and extent of in-vivo nickel release from an implanted device. The model was initially parameterized using data in the literature on in-vitro nickel release from a nickel-containing alloy (nitinol) and baseline serum nickel levels in humans. The results of this first step were then used to validate specific components of the model. The remaining unknown quantities were fit using serum values reported in patients following implantation with nitinol atrial occluder devices. The model is not only consistent with levels of nickel in serum and urine of patients following treatment with the atrial occluders, but also the optimized parameters in the model were all physiologically plausible. The congruity of the model with available data suggests that it can provide a framework to interpret nickel biomonitoring data and use data from in-vitro nickel immersion tests to estimate in-vivo nickel release from implanted cardiovascular devices.

Topics: Alloys; Biomarkers; Body Burden; Cardiovascular Diseases; Diffusion; Humans; Kinetics; Models, Biological; Models, Statistical; Nickel; Prosthesis Design; Prosthesis Implantation; Reproducibility of Results; Risk Assessment; Tissue Distribution

Sternal stability is essential to prevent serious infective complications after sternotomy. This paper examines whether nitinol thermoreactive clips reduce sternal wound infection rates in obese patients [body mass index (BMI) ≥30] compared with sternal wires.. All patients with BMI ≥30 undergoing cardiac surgery via median sternotomy between February 2008 and February 2013 in our institution were divided into two groups depending on sternal closure technique-sternal wires or thermoreactive clips. Comparison was made using propensity-matched analysis with sternal wound infection as the primary outcome.. Of 1371 patients, 826 (60%) had thermoreactive clips and 545 (40%) sternal wires. The sternal wires group was older (mean age 66.62 ± 10.1 vs 64.35 ± 9.8 years, P = 0.00) with a greater proportion of females (39 vs 26%, P = 0.00). In unmatched group comparison, both superficial sternal wound infection (thermoreactive clips 4% vs wires 3%) and deep infection (thermoreactive clips 3% vs wires 0.6%, P = 0.00) were more common in the thermoreactive clips group. More patients in the thermoreactive clips group required debridement and a larger number had vacuum-assisted closure [thermoreactive clips 10 patients (1%) vs sternal wires 2 (0.4%)]. Propensity-matching yielded two groups of 356 patients. There was no difference in sternal wound infection rates [thermoreactive clips 19 patients (5%) vs sternal wires 15 (4%), P = 0.58] or deep sternal infection rates [thermoreactive clips 9 patients (3%) vs sternal wires 3 (1%), P = 0.11].. Thermoreactive clips did not have an advantage in the prevention of superficial or deep sternal wound infection in obese patients undergoing sternotomy.

Topics: Aged; Alloys; Biocompatible Materials; Bone Wires; Cardiovascular Diseases; Female; Humans; Male; Middle Aged; Obesity; Propensity Score; Reoperation; Sternotomy; Sternum; Surgical Instruments; Surgical Wound Infection; Treatment Outcome; Wound Closure Techniques

We aim to deliver large appliances into the left ventricle through the right ventricle and across the interventricular septum. This transthoracic access route exploits immediate recoil of the septum, and lower transmyocardial pressure gradient across the right versus left ventricular free wall. The route may enhance safety and allow subxiphoid rather than intercostal traversal.. The entire procedure was performed under real-time CMR guidance. An "active" CMR needle crossed the chest, right ventricular free wall, and then the interventricular septum to deliver a guidewire then used to deliver an 18Fr introducer. Afterwards, the right ventricular free wall was closed with a nitinol occluder. Immediate closure and late healing of the unrepaired septum and free wall were assessed by oximetry, angiography, CMR, and necropsy up to four weeks afterwards.. The procedure was successful in 9 of 11 pigs. One failed because of refractory ventricular fibrillation upon needle entry, and the other because of inadequate guidewire support. In all ten attempts, the right ventricular free wall was closed without hemopericardium. There was neither immediate nor late shunt on oximetry, X-ray angiography, or CMR. The interventricular septal tract fibrosed completely. Transventricular trajectories planned on human CT scans suggest comparable intracavitary working space and less acute entry angles than a conventional atrial transseptal approach.. Large closed-chest access ports can be introduced across the right ventricular free wall and interventricular septum into the left ventricle. The septum recoils immediately and heals completely without repair. A nitinol occluder immediately seals the right ventricular wall. The entry angle is more favorable to introduce, for example, prosthetic mitral valves than a conventional atrial transseptal approach.

Topics: Aged; Alloys; Animals; Cardiac Catheterization; Cardiac Catheters; Cardiovascular Diseases; Feasibility Studies; Female; Fibrosis; Heart Ventricles; Hemodynamics; Humans; Magnetic Resonance Imaging, Interventional; Male; Middle Aged; Models, Animal; Prosthesis Design; Punctures; Septal Occluder Device; Swine; Time Factors; Tomography, X-Ray Computed; Ventricular Function; Ventricular Septum; Wound Healing

Previously, the Stenting and Angioplasty with Protection of Patients with High Risk for Endarterectomy (SAPPHIRE) randomized trial showed that carotid artery stenting (CAS) was not inferior to carotid endarterectomy (CEA) in the treatment of high-surgical risk patients.. The primary objective of the SAPPHIRE Worldwide Registry is to evaluate 30-day major adverse events (MAE) after CAS performed by physicians with varied experience and utilizing a formal training program. Data will be analyzed on the overall patient population and by high-risk inclusion criteria.. SAPPHIRE Worldwide is a multicenter, prospective, postapproval registry to evaluate CAS with distal protection in patients at high-risk for surgery using the Cordis PRECISE Nitinol Stent and ANGIOGUARD XP/RX Emboli Capture Guidewire. Participating physicians are encouraged to treat patients according to their standard of practice and consistent with current Food and Drug Administration-approved labeling.. Enrollment began in October 2006. Data are available on the first 2,001 patients enrolled and followed to 30 days. Of these patients, the mean age was 72.2 +/- 9.75 yr; 62% were male; and 27.7% were symptomatic. Entry criteria for surgical high-risk included anatomic (n = 716), physiologic (n = 918), or both risk factors (n = 327). At 30-day follow-up, the MAE was 4.4% (death 1.1%, stroke 3.2%, MI 0.7%) for the overall population. Patients with anatomic risk had a significantly lower 30-day MAE than patients with physiologic risk (2.8% vs. 4.9%, P = 0.0306), respectively.. While the number of physicians performing CAS continues to increase, MAE rates seen in this registry (4.4%) are well within an acceptable range, as was first seen in the SAPPHIRE randomized trial (4.8%). A significant decrease in MAE was seen in patients with anatomic risk compared with physiologic risk factors. The SAPPHIRE Worldwide Registry supports the use of CAS as an alternative to CEA in patients who are at high-risk for surgery due to anatomic risk factors.

Topics: Aged; Aged, 80 and over; Alloys; Angioplasty; Canada; Cardiovascular Diseases; Carotid Stenosis; Clinical Competence; Education, Medical; Embolism; Endarterectomy, Carotid; Female; Humans; Logistic Models; Male; Middle Aged; Odds Ratio; Patient Selection; Practice Guidelines as Topic; Prospective Studies; Prosthesis Design; Registries; Risk Assessment; Risk Factors; Stents; Time Factors; Treatment Outcome; United States

Topics: Alloys; Angioplasty; Cardiovascular Diseases; Carotid Stenosis; Clinical Competence; Education, Medical; Endarterectomy, Carotid; Humans; Patient Selection; Practice Guidelines as Topic; Prospective Studies; Prosthesis Design; Risk Assessment; Risk Factors; Stents; Time Factors; Treatment Outcome

This study examined whether physicians with varying carotid stent experience would obtain safety and efficacy outcomes as good as those from the pivotal SAPPHIRE trial following participation in a comprehensive carotid stent training program.. This study was performed as a condition of approval study for the PRECISE(R) Nitinol Stent and the ANGIOGUARD XP Emboli Capture Guidewire.. Patients at high surgical risk who were either symptomatic with >or=50% stenosis or asymptomatic with >or=80% stenosis of the common or internal carotid artery received carotid artery stenting with distal emboli protection using the PRECISE Nitinol Stent and the ANGIOGUARD XP Emboli Capture Guidewire. Physicians were qualified based on either prior experience in carotid stenting with the ANGIOGUARD XP Emboli Capture Guidewire or following participation in a formal training program. The primary endpoint of major adverse events (MAE) at 30 days (death, myocardial infarction (MI), or stroke) was tested for non-inferiority compared with an objective performance criterion (OPC) of 6.3% established from the stent cohort of the SAPPHIRE trial.. The 30-day MAE rate was 5.0%, meeting the criteria for non-inferiority to the prespecified OPC (95% CI [3.9%, 6.2%] P<0.001). Asymptomatic patients (N=1,158, 78.2%) had similar outcomes to the overall results (MAE 4.7%). Outcomes were similar across levels of physician experience, carotid stent volume, geographic location, presence/absence of training program.. Utilizing a comprehensive training program, carotid artery stenting by operators with differing experience in a variety of practice settings yielded safety and efficacy outcomes similar to those reported in the SAPPHIRE trial.

Topics: Aged; Aged, 80 and over; Alloys; Angioplasty; Cardiovascular Diseases; Carotid Stenosis; Clinical Competence; Device Approval; Education, Medical; Embolism; Equipment Design; Female; Humans; Incidence; Male; Product Surveillance, Postmarketing; Prosthesis Design; Registries; Severity of Illness Index; Stents; Time Factors; Treatment Outcome; United States