Polymer stent coatings may not be suitable for drug elution because of inherent proinflammatory effects. A previous study suggested a beneficial effect of a stent eluting tacrolimus from a nanoporous ceramic aluminum oxide coating in a rabbit restenosis model. We investigated whether this stent is effective in preventing in-stent restenosis in a porcine restenosis model. Thirty-four juvenile swine underwent balloon overstretch injury and were subjected to implantation of either stainless steel (bare) stents, bare stents coated with nanoporous aluminum oxide alone, and coated stents eluting 50 and 180 mug of tacrolimus (FK506). In-stent restenosis was quantified at 1 and 3 months after stent placement by histomorphometry. A significant increase of neointimal hyperplasia was noted with the stents coated with aluminum oxide alone compared with bare stents (2.92 +/- 1.02 and 1.38 +/- 0.51 mm(2), respectively; P < 0.02). In all arteries containing coated stents, particle debris was found in the media and neointima, resulting in augmented vascular inflammation. In the group of stents coated with aluminum oxide, FK506 elution at a dose 180 mug reduced neointimal hyperplasia vs. no drug elution (1.66 +/- 0.49 vs. 2.92 +/- 1.02 mm(2); 180 mug vs. ceramic alone; P < 0.03). At a dose of 50 mug stent-based delivery of FK506, no reduction of neointimal hyperplasia was found (2.88 +/- 1.31 and 2.92 +/- 1.02 mm(2), respectively; P = NS; FK506 vs. ceramic alone). In summary, particle debris shed from a drug-eluting aluminum oxide coating of a stainless steel stent counteracts potential antiproliferative effects of stent-based tacrolimus delivery in a porcine model of restenosis. We propose that stent coatings eluting drugs need to be routinely tested for being tightly anchored into the stent surface. Alternatively, omission of any coating used as a drug reservoir may eliminate inflammatory particle debris after placement of drug-eluting stents.

Both cell proliferation and apoptosis (programmed cell death) are supposed to play a role in restenosis after angioplasty. We studied these processes in smooth muscle cells (SMCs) and macrophages 1, 4, and 12 weeks after balloon angioplasty or Palmaz-Schatz stent implantation in rabbit iliac arteries. Proliferating cells were visualized by immunostaining with antibodies directed against proliferating cell nuclear antigen. Apoptotic cells were detected using the TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick and labeling) technique, propidium iodide staining, and transmission electron microscopy. At all time points, the neointimal cross-sectional area of the arteries was twofold to fourfold greater after stent implantation than after balloon angioplasty. The total number of neointimal cells was similar 1 and 12 weeks after both interventions. The neointimal cell density, however, decreased by 58% between the 1st and the 12th week after stent implantation compared with a 20% decrease after balloon angioplasty (P < .01). Stent implantation induced more cell proliferation but also more apoptosis in the media than balloon angioplasty after 1 and 4 weeks. In addition, stent implantation caused more macrophage accumulation and apoptosis in the neointima, but cell proliferation rates did not differ significantly in comparison with balloon angioplasty. The higher rate of apoptosis in the neointima 1 week after stent implantation compared with balloon angioplasty is due to an increased rate of SMC and macrophage death. Macrophage accumulation and apoptosis in the early phase after stent implantation appear to play a role in extracellular matrix secretion, which increases neointima formation after 4 and 12 weeks compared with balloon angioplasty in this model.

Background and Purpose-We hypothesized that for the prediction or exclusion of aortic thrombi or plaques Ն4 mm, the combination of intima-media thickness (IMT) and distensibility (DC) of the common carotid arteries would be superior to the measurement of IMT alone. Methods-We prospectively included 208 stroke patients (mean age, 60 years) undergoing transesophageal echocardiography for screening of aortic plaques. IMT and DC were determined by ultrasound, and DC was quantified by measuring blood pressure and the common carotid arteries diameter change on M-mode ultrasound during the cardiac cycle. Results-Negative predictive values of IMT Ͻ0.9 mm and DC Ն24ϫ10 Ϫ3 /kPa for the exclusion of aortic atheroma Ն4 mm were similar (92.0% and 91.7%, respectively). However, negative predictive values increased to 98.2% and to 100.0% for the exclusion of aortic thrombi when both parameters were combined. Positive predictive values of IMT Ն0.9 mm and DC Ͻ24 were lower (46.3%, 41.1%; respectively), but they also increased in combination (54.3%). Conclusions-Our findings suggest that IMT and DC represent different vessel wall properties and that measuring both parameters provides optimized characterization of carotid atherosclerosis. Combining IMT and DC increases the predictive power of carotid ultrasound, making transesophageal echocardiography dispensable for assessment of the aorta for those with normal carotid arteries and indispensable for those patients with carotid atherosclerosis. (Stroke. 2006;37:2708-2712.)

The SJM Confirm DM2102 can accurately and repeatedly detect paroxysmal AF episodes of at least 2 minutes in length.

Edge restenosis following gamma irradiation treatment of ISR is related to GM: a mismatch between the segment of artery injured during the primary catheter-based intervention and the length of the radiation source.

The combination of morphologic and hemodynamic information can help in assessing the risk of embolic stroke associated with thrombi and plaques in the descending aorta. For two acute stroke patients, the determination of individual embolic pathways using flow-sensitive four-dimensional (4D) MRI are reported. 3D visualization of local flow patterns, i.e., retrograde flow channels originating at the site of the atheroma, in conjunction with exact plaque localization, suggested potential embolization of high-risk plaques in the descending aorta although they are located downstream from the supraaortic arteries. Our findings indicate that taking plaques of the descending aorta into consideration may help improve the spectrum of pathologies considered as high-risk sources for brain ischemia.

In-stent restenosis (ISR) is a major problem within stented arteries. Surface treatment of stents with platinum and gold were found to have the maximum charge with least neointima formation (NF). This study was designed to evaluate platinum (maximum electrical charge) as a material to make stents to reduce NF. Iridium was added to make an alloy suitable for stent manufacture, with the potential to make the stent radioactive. We implanted the novel platinum-iridium (PI) stent in 10 porcine coronaries and compared to the Palmaz-Schatz (PS) stent implanted in 8 coronary arteries. Six weeks after implantation, angiography of the stented vessel was performed before sacrifice. The coronaries were perfusion-fixed and stained, and vessel parameters were analyzed by computer-aided histomorphometry. The thrombus formation and the inflammatory response was less in the PI stent (0.04 +/- 0.1 vs. 0.24 +/- 0.2, P = 0.005; and 1.1 +/- 0.5 vs. 2.4 +/- 0.3, P < 0.001). The NF from PI-stented arteries was smaller in size than the PS controls (1.9 +/- 0.6 mm(2) vs. 2.4 +/- 0.4 mm(2), P = 0.06). However, PI stents presented with higher recoil than the PS stent (16% vs. 5%, P < 0.001). Platinum-iridium is a highly biocompatible material with high performance, low inflammatory response with small NF. This stent does not lead to thrombus formation and has the potential (due to the presence of iridium) to be irradiated to form a gamma radioactive stent. Cathet. Cardiovasc. Intervent. 51:364-368, 2000.

Although less invasive then SAVR, TAVI is associated with a significant rate of access site and non-access site bleeding. These complications are major determinants of therapy outcome, however, the economic consequences are not well defined. The purpose of this study was to determine the relationship between bleeding, in-hospital resource utilization and costs among patients undergoing transfemoral aortic valve implantation (TF-AVI) at a representative university hospital in Germany. Between February 2010 and December 2011, we prospectively enrolled 60 consecutive patients undergoing TAVI using a 18F transfemoral approach at our institution. The relationship between overt bleeding (OVB), defined according to the definitions provided by the Valve Academic Research Consortium, in-hospital resource utilization and in-hospital costs was investigated. The mean age was 82 (±6) years, 53% were female and the mean EuroScore was 17.2% (±8, 7). Thirty-eight percent (23/60) of the patients had an OVB following TF-AVI procedure. In-hospital mortality was 8.7% in the OVB patients (2/23) and 2.7% among patients without any OVB (1/37; NOVB), which was not statistically significant (p = 0.3). The total length of stay (LOS) of patients with and without bleeding complication were 15.0 ± 6.4 and 10.4 ± 5.1 days, respectively (p < 0.01). Time spent on ICU in the OVB group was twice as long as compared to the NOVB group (120.5 ± 98.5 min vs. 63.6 ± 26.5 min, p < 0.01). Consequently, in-hospital costs were statistically significant higher in OVB patients (40.051 ± 9.293 vs. 33.625 ± 4.368, p < 0.01). Bleeding is associated with increased resource use and in-hospital costs among TF-AVI patients. Our data indicates that strategies reducing bleeding risk may have the potential to generate important in-hospital costs reductions in TF-AVI patients.