Long-term Outcomes of Drug-eluting versus Bare-metal stent for ST-elevation Myocardial Infarction

Background

Long-term outcomes of drug-eluting stents (DES) versus bare-metal stents (BMS) in patients with ST-segment elevation myocardial infarction (STEMI) remain uncertain.

Objective

To investigate long-term outcomes of drug-eluting stents (DES) versus bare-metal stents (BMS) in patients with ST-segment elevation myocardial infarction (STEMI).

Methods

We performed search of MEDLINE, EMBASE, the Cochrane library, and ISI Web of Science (until February 2013) for randomized trials comparing more than 12-month efficacy or safety of DES with BMS in patients with STEMI. Pooled estimate was presented with risk ratio (RR) and its 95% confidence interval (CI) using random-effects model.

Results

Ten trials with 7,592 participants with STEMI were included. The overall results showed that there was no significant difference in the incidence of all-cause death and definite/probable stent thrombosis between DES and BMS at long-term follow-up. Patients receiving DES implantation appeared to have a lower 1-year incidence of recurrent myocardial infarction than those receiving BMS (RR = 0.75, 95% CI 0.56 to 1.00, p= 0.05). Moreover, the risk of target vessel revascularization (TVR) after receiving DES was consistently lowered during long-term observation (all p< 0.01). In subgroup analysis, the use of everolimus-eluting stents (EES) was associated with reduced risk of stent thrombosis in STEMI patients (RR = 0.37, p=0.02).

Conclusions

DES did not increase the risk of stent thrombosis in patients with STEMI compared with BMS. Moreover, the use of DES did lower long-term risk of repeat revascularization and might decrease the occurrence of reinfarction.     

Angiographic results of the cobalt chromium Vision and Mini-Vision stents

BACKGROUND:

Drug-eluting stents (DES) have been shown to reduce repeat revascularizations compared with their bare-metal stent (BMS) platforms. Modern BMS may be associated with better angiographic results compared with the older BMS platforms. In the Basel Stent Kosten Effektivitats Trial (BASKET), target vessel revascularization after six months was nonsignificantly different between DES and BMS with clinical follow-up.

OBJECTIVES:

To evaluate angiographic results of the cobalt chromium Vision and Mini-Vision stents (Abbott Vascular, USA).

METHODS:

A total of 247 consecutive patients with 293 de novo lesions in native coronary arteries were treated with cobalt chromium Vision (n=184; stent diameter 2.75 mm to 4.0 mm) or Mini-Vision stents (n=109; stent diameter 2.0 mm to 2.5 mm), and scheduled for six months of angiographic follow-up. The primary end point was in-stent late loss after six months.

RESULTS:

Acute coronary syndromes were present in 83.4% (n=206) of patients. The preinterventional reference diameter of Vision stents was 2.70±0.34 mm and for Mini-Vision stents, it was 2.13±0.27 mm (P<0.001). Clinical and angiographic follow-up was 98.0% and 51.2%, respectively. In the Vision group, in-stent late loss was 0.64±0.67 mm and the binary rest-enosis rate was 17.9%. In the Mini-Vision group, in-stent late loss was 0.82±0.71 mm and the restenosis rate was 45.4%. No difference in occurrence of restenosis within the segments proximal or distal to the stent was observed. The restenotic pattern was predominantly focal with a short length of 7.9±4.4 mm.

CONCLUSIONS:

The use of the cobalt chromium Vision stent for the treatment of de novo lesions was associated with a low late loss and binary angiographic restenosis rate.     

Three-year data from the XIENCE V® INDIA study: Safety and efficacy of XIENCE V® in 1000 real world Indian patients

Background

Cardiovascular disease in Asia has reached epidemic proportions in recent years. Use of drug eluting stents in Asians has rapidly expanded with varying penetration rates across different countries. The XIENCE V^® INDIA Study included ‘real world’ patients who underwent XIENCE V^® stent implantation to assess short and intermediate term outcomes in Indian patients with diverse risk factors.

Objective

To evaluate 3-year clinical outcomes in a cohort of ‘real world’ Indian patients with CAD being treated with XIENCE V^® Everolimus Eluting Coronary Stent System.

Methods

1000 patients were enrolled from 18 sites in India between June 2008 and March 2009. Patients were included if their index procedures were completed using only XIENCE V^®. There were no clinical or angiographic exclusions. An independent Clinical Events Committee adjudicated all endpoint-related events. The primary endpoint was stent thrombosis rate annually through to 3 years as defined by the Academic Research Consortium criteria. The co-primary endpoint was the composite rate of cardiac death and myocardial infarction at 1 year.

Results

At 1-year the primary endpoint of definite/probable stent thrombosis rate was 0.51%. No additional very late stent thrombosis was reported through a 3-year follow up. The composite endpoint of cardiac death and any myocardial infarction was 1.9%, 2.7% and 3.1% at 1, 2 and 3 years respectively.

Conclusion

Despite the high risk population of coronary artery disease, the use of XIENCE V^® in ''real world'' Indian patients was associated with very low clinical event rates upto three years of follow up.     

Clinical Coronary In-Stent Restenosis Follow-Up after Treatment and Analyses of Clinical Outcomes

Background

Clinical in-stent restenosis (CISR) is the main limitation of coronary angioplasty with stent implantation.

Objective

Describe the clinical and angiographic characteristics of CISR and the outcomes over a minimum follow-up of 12 months after its diagnosis and treatment.

Methods

We analyzed in 110 consecutive patients with CISR the clinical presentation, angiographic characteristics, treatment and combined primary outcomes (cardiovascular death, nonfatal acute myocardial infarction [AMI]) and combined secondary (unstable angina with hospitalization, target vessel revascularization and target lesion revascularization) during a minimal follow-up of one year.

Results

Mean age was 61 ± 11 years (68.2% males). Clinical presentations included acute coronary syndrome (ACS) in 62.7% and proliferative ISR in 34.5%. CISR was treated with implantation of drug-eluting stents (DES) in 36.4%, Bare Metal Stent (BMS) in 23.6%, myocardial revascularization surgery in 18.2%, balloon angioplasty in 15.5% and clinical treatment in 6.4%. During a median follow-up of 19.7 months, the primary outcome occurred in 18 patients, including 6 (5.5%) deaths and 13 (11.8%) AMI events. Twenty-four patients presented a secondary outcome. Predictors of the primary outcome were CISR with DES (HR = 4.36 [1.44–12.85]; p = 0.009) and clinical treatment for CISR (HR = 10.66 [2.53–44.87]; p = 0.001). Treatment of CISR with BMS (HR = 4.08 [1.75–9.48]; p = 0.001) and clinical therapy (HR = 6.29 [1.35–29.38]; p = 0.019) emerged as predictors of a secondary outcome.

Conclusion

Patients with CISR present in most cases with ACS and with a high frequency of adverse events during a medium-term follow-up.     

Efficacy and Safety of Drug-Eluting Stents in the Real World: 8-Year Follow-Up

Background:

Drug-eluting stents have been used in daily practice since 2002, with the clear advantages of reducing the risk of target vessel revascularization and an impressive reduction in restenosis rate by 50%-70%. However, the occurrence of a late thrombosis can compromise long-term results, particularly if the risks of this event were sustained. In this context, a registry of clinical cases gains special value.

Objective:

To evaluate the efficacy and safety of drug-eluting stents in the real world.

Methods:

We report on the clinical findings and 8-year follow-up parameters of all patients that underwent percutaneous coronary intervention with a drug-eluting stent from January 2002 to April 2007. Drug-eluting stents were used in accordance with the clinical and interventional cardiologist decision and availability of the stent.

Results:

A total of 611 patients were included, and clinical follow-up of up to 8 years was obtained for 96.2% of the patients. Total mortality was 8.7% and nonfatal infarctions occurred in 4.3% of the cases. Target vessel revascularization occurred in 12.4% of the cases, and target lesion revascularization occurred in 8% of the cases. The rate of stent thrombosis was 2.1%. There were no new episodes of stent thrombosis after the fifth year of follow-up. Comparative subanalysis showed no outcome differences between the different types of stents used, including Cypher®, Taxus®, and Endeavor®.

Conclusion:

These findings indicate that drug-eluting stents remain safe and effective at very long-term follow-up. Patients in the "real world" may benefit from drug-eluting stenting with excellent, long-term results.     

Long-term clinical outcomes of drug-eluting stents vs. bare-metal stents in Chinese geriatric patients

Background & Objective Little is known about the relative efficacies of percutaneous coronary intervention (PCI) with drug-eluting stents (DES) and bare-metal stents (BMS) in elderly patients. The objective of this study was to evaluate the clinical outcome for geriatric patients who received either DES or BMS. Methods From January 2002 to October 2005, 199 consecutive Chinese geriatric patients (≥ 75 years old) underwent PCI with coronary DES or BMS implantation at our institution. We analyzed the major clinical end points that included all-cause mortality, cardiovascular death, myocardial infarction, target lesion revascularization (TLR), stent thrombosis, and bleeding complications. Results The three-year cumulative rates of all-cause mortality, cardiovascular death, and myocardial infarction were significantly lower in the DES group (6.3%, 3.6%, 5.4%) compared with the BMS group (16.2%, 11.5%, 14.9%; P < 0.05). No significant differences were found in the three-year cumulative rate for target lesion revascularization (6.3% vs. 4.6%, P = 0.61) or stent thrombosis (3.6% vs. 2.3%, P = 0.70). Likewise, there were no statistically significant differences in the cumulative rate for intracranial hemorrhage, or major and minor hemorrhage at three years. Conclusions DES-based PCI was associated with a significant reduction in the three-year cumulative rate of all-cause mortality, cardiovascular death, and myocardial infarction compared with BMS, without increased risk of TLR, stent thrombosis, or bleeding complications at three years in this group of Chinese geriatric patients.     

Efficacy and safety of low-dose clopidogrel after 12-month dual antiplatelet therapy for patients having drug-eluting stent implantation

Background

To prevent stent thrombosis (ST) after implantation of drug-eluting stents (DESs) in patients with coronary heart disease, 12-month dual antiplatelet therapy (DAPT) is recommended. However, the optimal long-term antiplatelet regimen is not clear for the patients who have completed the 12-month DAPT.

Methods

We reviewed the data of 755 consecutive patients who had undergone percutaneous coronary intervention (PCI) three years ago and completed 12-month DAPT. They were divided into three groups according to the antiplatelet medication they had used for two years after 12-month DAPT [low-dose clopidogrel (Talcom^®, 25mg/d), clopidogrel (Plavix^®, 75mg/d) and aspirin (100 mg/d)]. The efficacy (a composite incidence of cardiac death, myocardial infarction and target vessel revascularization) and safety (incidences of bleeding, gastrointestinal trouble and drug discontinuation) were compared among the three groups.

Results

The rates of multi-vessel lesions, prior MI, hemoglobin A1C (HbA1c) and low-density lipoprotein cholesterol were significantly higher in the clopidogrel (75 mg/day) group than in the other two groups (P>0.05 for both comparisons). There was no significant difference in the overall composite incidence of cardiac death, myocardial infarction and target vessel revascularization in the three groups at three years after PCI. The rates of bleeding (especially minor bleeding), gastrointestinal trouble, drug discontinuation and any blood transfusion were markedly lower in the low-dose clopidogrel (25 mg/d) group than in the other two treatment groups (P<0.05).

Conclusions

The 25-mg maintenance dose of clopidogrel after 12-month DAPT may be more preferable to Chinese patients who have undergone DES implantation, because of its lower cost but no less efficacy and safety.     

Design of a registry to characterize "real-world" outcomes of percutaneous coronary revascularization in the drug-eluting stent era

Background

Clinical trials have shown drug-eluting stents (DES) to be superior to bare metal stents (BMS) in preventing in-stent restenosis and target vessel revascularization. Although these results have ushered in a sea change in the practice of myocardial revascularization, important questions remain unanswered concerning rates of ischemic complications when DES are used in a broader population not represented in the clinical trials.

Study Design

The EVENT registry will include 7500 to 10 000 patients enrolled at approximately 60 sites across the United States. The intent of the registry is to characterize a population of consecutive patients undergoing percutaneous coronary intervention with stent deployment using BMS and DES in terms of processes and outcomes of care. A unique aspect of EVENT is the prospective assessment of rates of periprocedural myocardial infarction among all patients. These data will allow us to compare rates of periprocedural myocardial infarction and other ischemic complications between patients receiving DES and BMS. In addition, the EVENT registry will characterize temporal changes in the patterns of DES use and the relationship between any such changes and both short- and long-term outcomes.     

Neo-atherosclerosis in very late stent thrombosis of drug eluting stent

Background

Recent studies have described neo-atherosclerosis, developing inside the stent, as cause of very late stent thrombosis.

Case report

A 59-year-old man, with family history of coronary artery disease, presented to our Department because of anterior ST-segment elevation myocardial infarction. Two years before he had underwent percutaneous coronary intervention with multiple drug-eluting stents (DES) implantation on proximal-mid left anterior descending artery (LAD), and mid-right coronary artery (RCA), respectively. The angiogram revealed stent thrombosis with total occlusion of proximal LAD. Multiple passages with manual thrombus-aspiration catheter were successfully performed with improvement in TIMI flow. Optical Coherence Tomography (OCT) imaging revealed fully expanded stents without areas of inappropriate apposition to vessel wall; and mild to moderate intimal hyperplasia throughout the stented segment, with full covered stent struts; areas of ulcerated and ruptured plaque within the proximal struts of stented segment was depicted with intraluminal protruding material. Thus, an additional bare metal stent (BMS) was deployed inside and overlapping the previous in order to seal this plaque. OCT post procedure revealed optimal stent expansion and apposition, without residual protruding material. At 9-month follow-up patient was alive and free from symptoms. Coronary angiogram revealed patency of implanted stents without significant restenosis.

Conclusions

Neo-atherosclerosis with thrombosis on top of ruptured necrotic plaque core may play a role in the pathophysiology of very late stent thrombosis in both BMS and DES. Our report highlights the role OCT to assess the mechanism of VLST.     

Preclinical Study of a Biodegradable Polymer-based Stent with Abluminal Sirolimus Release

Background

Bioabsorbable polymer stents with drug elution only on the abluminal surface may be safer than durable polymer drug-eluting stents.

Objective

To report the experimental findings with the Inspiron^TM stent - a bioabsorbable polymer-coated stent with sirolimus release from the abluminal surface only, recently approved for clinical use.

Methods

45 stents were implanted in the coronary arteries of 15 pigs. On day 28 after implantation, angiographic, intracoronary ultrasonographic and histomorphological data were collected. Five groups were analyzed: Group I (nine bare-metal stents); Group II (nine coated with bioabsorbable polymer on the luminal and abluminal surfaces); Group III (eight stents coated with bioabsorbable polymer on the abluminal surface); Group IV (nine stents with bioabsorbable polymer and sirolimus on the luminal and abluminal surfaces); and Group V (ten stents with bioabsorbable polymer and sirolimus only on the abluminal surface).

Results

The following results were observed for Groups I, II, III, IV and V, respectively: percentage stenosis of 29 ± 20; 36 ± 14; 33 ± 19; 22 ± 13 and 26 ± 15 (p = 0.443); late lumen loss (in mm) of 1.02 ± 0.60; 1.24 ± 0.48; 1.11 ± 0.54; 0.72 ± 0.44 and 0.78 ± 0.39 (p = 0.253); neointimal area (in mm²) of 2.60 ± 1.99; 2.74 ± 1.51; 2.74 ± 1.30; 1.30 ± 1.14 and 0.97 ± 0.84 (p = 0.001; Groups IV and V versus Groups I, II and III); and percentage neointimal area of 35 ± 25; 38 ± 18; 39 ± 19; 19 ± 18 and 15 ± 12 (p = 0.001; Groups IV and V versus Groups I, II and III). Injury and inflammation scores were low and with no differences between the groups.

Conclusion

The Inspiron^TM stent proved to be safe and was able to significantly inhibit the neointimal hyperplasia observed on day 28 after implantation in porcine coronary arteries.     

Intravascular ultrasound assessed incomplete stent apposition and stent fracture in stent thrombosis after bare metal versus drug-eluting stent treatment the Nordic Intravascular Ultrasound Study (NIVUS)

Background

This prospective multicenter registry used intravascular ultrasound (IVUS) in patients with definite stent thrombosis (ST) to compare rates of incomplete stent apposition (ISA), stent fracture and stent expansion in patients treated with drug-eluting (DES) versus bare metal (BMS) stents. ST is a rare, but potential life threatening event after coronary stent implantation. The etiology seems to be multifactorial.

Methods

124 patients with definite ST were assessed by IVUS during the acute ST event. The study was conducted in 15 high-volume percutaneous coronary intervention -centers in the Nordic–Baltic countries.

Results

In early or late ST there were no differences in ISA between DES and BMS. In very late ST, ISA was a more frequent finding in DES than in BMS (52% vs.16%; p = 0.005) and the maximum ISA area was larger in DES compared to BMS (1.1 ± 2.3 mm² vs. 0.1 ± 0.5 mm²; p = 0.004). Further, ISA was more prevalent in sirolimus-eluting than in paclitaxel-eluting stents (58% vs. 37%; p = 0.02). Stent fractures were found both in DES (16%) and BMS (24%); p = 0.28, and not related to time of stent thrombosis occurrence. For stents with nominal diameters ≥ 2.75 mm, 38% of the DES and 22% of the BMS had a minimum stent area of less than 5 mm²; p = 0.14.

Conclusions

Very late stent thrombosis was more prevalent and associated with more extensive ISA in DES than in BMS treated patients. Stent fracture was a common finding in ST after DES and BMS implantation.     

Fracture of Zotarolimus-Eluting Stent after Implantation

Drug-eluting stents were developed and approved for the reduction of in-stent restenosis. However, restenosis still occurs, and stent fracture is suggested as a cause of restenosis after implantation. Although sirolimus-eluting stents are considered to carry a high risk of fracture, the risk is also present with other drug-eluting stents. Herein, we report the case of a 78-year-old woman who received a zotarolimus-eluting stent for a bifurcation lesion of the left anterior descending coronary artery. Ten months later, she underwent coronary angiography due to angina. The angiogram revealed in-stent restenosis, with a grade IV stent fracture. After percutaneous coronary angioplasty, the patient''s clinical symptoms improved.Key words: Blood vessel prosthesis implantation/instrumentation, coronary restenosis/diagnosis/etiology/prevention & control, drug-eluting stents, drug implants/adverse effects, prosthesis failure, retreatment, stents/adverse effectsAlthough drug-eluting stents (DESs) reduce in-stent restenosis, important complications of coronary DESs are restenosis and thrombosis. Stent fractures have also been reported¹ and are considered to be possible causes of restenosis² within DESs. The sirolimus-eluting stent is reported to be prone to fracture.³ For example, there is the Cypher® stent (Cordis Corporation, a Johnson & Johnson company; Miami Lakes, Fla)—made of balloon-expandable stainless steel, a durable copolymer mixture of polyethylene-covinyl acetate and poly-u-butyl methacrylate, and sirolimus, which is a Gap 1 (G1) cell-cycle inhibitor.⁴ Other DESs are also considered to be at risk of fracture. One, the Endeavor® Sprint Zotarolimus-Eluting Coronary Stent System (Medtronic, Inc.; Minneapolis, Minn), uses a cobalt chromium stent platform; a durable, antithrombotic, phosphorylcholine-encapsulated coating; and another G1 cell-cycle inhibitor, zotarolimus.⁴ Here, we report the case of a woman who was treated with a zotarolimus-eluting stent that subsequently fractured.     

Evaluation of an easy and affordable flow cytometer for volumetric haematopoietic stem cell counting

Background

Accurate estimation of haematopoietic stem cell (HSC) counts by flow cytometry may be difficult in laboratories in which sophisticated equipment and staff with specific expertise are not available. Affordable flow cytometers that can perform basic functions may help to overcome these difficulties. In this study we compared HSC and leucocyte counts determined by volumetric and bead-based protocols performed with the small, low-cost Accuri^® C6, with those obtained with two gold-standard instruments, the four-colour FACSCalibur^® and the eight-colour FACSCantoII^®, our reference flow cytometers.

Materials and methods

With the three cytometers we tested, in parallel, 111 consecutive samples from cord blood, peripheral blood from patients with myelofibrosis and myeloproliferative syndromes, fresh and thawed HSC collected by apheresis and bone marrow products. The findings were compared with one-way ANOVA, Bland-Altman analysis and linear regression.

Results

The results of HSC and leucocyte enumeration by the three devices were strongly correlated (r²>0.99; p<0.0001). ANOVA performed on different subgroups of samples did not reveal significant differences between HSC count determined by the C6 bead-based and reference flow cytometers in any of the subgroups. Regarding the C6 volumetric protocol, a statistically significant difference was observed only in the cord blood subgroup. Time for instrument set-up, calibration and analysis was slightly longer with Accuri^® C6 (40 min) than with FACSCantoII^® (30 min).

Discussion

Accuri^® C6 is a reliable instrument for HSC enumeration in fresh samples, using both volumetric and bead-based approaches, although the volumetric protocol on cord blood samples needs to be improved. The Accuri^® C6 is easy to use, does not require profound knowledge of flow cytometry and could be employed in an urgent setting. Its performance may be improved by more efficient calibration and shorter analysis time.     

Accuracy Evaluation of Five Blood Glucose Monitoring Systems: The North American Comparator Trial

Background

This study evaluated differences in accuracy between the CONTOUR^® NEXT EZ (EZ) blood glucose monitoring system (BGMS) and four other BGMSs [ACCU-CHEK^® Aviva (ACAP), FreeStyle Freedom Lite^® (FFL), ONE TOUCH^® Ultra^®2 (OTU2), and TRUEtrack^® (TT)].

Methods

Up to three capillary blood samples (N = 393) were collected from 146 subjects with and without diabetes. One sample per subject was tested with fresh (natural) blood; the other samples were glycolyzed to lower blood glucose to <70 mg/dl. Meter results were compared with results from plasma from the same sample tested on a Yellow Springs Instruments (YSI) 2300 STAT Plus™ glucose analyzer. Blood glucose monitoring system accuracy was compared using mean absolute relative difference (MARD; from laboratory reference method results) and other analyses. Separate analyses on fresh (natural) samples only were conducted to determine potential effects of glycolysis on MARD values of systems utilizing glucose-oxidase-based test strip chemistry.

Results

Across the tested glucose range, the EZ had the lowest MARD of 4.7%; the ACAP, FFL, OTU2, and TT had MARD values of 6.3%, 18.3%, 23.4%, and 26.2%, respectively. For samples with glucose concentrations <70 mg/dl, the EZ had the lowest MARD (0.65%), compared with the ACAP (2.5%), FFL (18.3%), OTU2 (22.4%), and TT (33.2%) systems.

Conclusions

The EZ had the lowest MARD across the tested glucose ranges when compared with four other BGMSs when all samples were analyzed as well as when natural samples only were analyzed.     

Cutting-balloon angioplasty before drug-eluting stent implantation for the treatment of severely calcified coronary lesions

Background Severely calcified coronary lesions respond poorly to balloon angioplasty, resulting in incomplete and asymmetrical stent expansion. Therefore, adequate plaque modification prior to drug-eluting stent （DES） implantation is the key for calcified lesion treat- ment. This study was to evaluate the safety and efficacy of cutting balloon angioplasty for severely calcified coronary lesions. Methods Ninety-two consecutive patients with severely calcified lesions （defined as calcium arc 〉 180% calcium length ratio 〉 0.5） treated with bal- loon dilatation before DES implantation were randomly divided into two groups based on the balloon type： 45 patients in the conventional balloon angioplasty （BA） group and 47 patients in the cutting balloon angioplasty （CB） group. Seven cases in BA group did not satisfactorily achieve dilatation and were transferred into the CB group. Intravascular ultrasound （IVUS） was performed before balloon dilatation and after stent implantation to obtain qualitative and quantitative lesion characteristics and evaluate the stent, including minimum lumen cross-sectional area （CSA）, calcified arc and length, minimum stent CSA, stent apposition, stent symmetry, stent expansion, vessel dissection, and branch vessel jail. In-hospital, 1-month, and 6-month major adverse cardiac events （MACE） were reported. Results There were no statistical differences in clinical characteristics between the two groups, including calcium arc （222.2° ± 22.2° vs. 235.0° ± 22.1 °, p=0.570）, calcium length ratio （0.67 ± 0.06 vs. 0.77± 0.05, P = 0.130）, and minimum lumen CSA before PCI （2.59 ±0.08 mm2 vs. 2.52 ± 0.08 mm2, P = 0.550）. After stent implantation, the final minimum stent CSA （6.26 ± 0.40 mm2 vs. 5.03 ± 0.33 mm2; P = 0.031） and acute lumen gain （3.74 ±0.38 mm2 w. 2.44 ± 0.29 mm2, P = 0.015） were significantly larger ila the CB group than that of the BA group. There were not statis tically differences in stent expansion, stent symmetry, incomplete stent apposition, vessel dissection and branch vessel jail between two groups. The 30-day and 6-month MACE rates were also not different. Conclusions Cutting balloon angioplasty before DES implantation in severely calcified lesions appears to be more efficacies including significantly larger final stent CSA and larger acute lumen gain, without increasing complications during operations and the MACE rate in 6-month.     

Comparative Dose Accuracy of Durable and Patch Insulin Infusion Pumps

Background:

As all major insulin pump manufacturers comply with the international infusion pump standard EN 60601-2-24:1998, there may be a general assumption that all pumps are equal in insulin-delivery accuracy. This research investigates single-dose and averaged-dose accuracy of incremental basal deliveries for one patch model and three durable models of insulin pumps.

Method:

For each pump model, discrete single doses delivered during 0.5 U/h basal rate infusion over a 20 h period were measured using a time-stamped microgravimetric system. Dose accuracy was analyzed by comparing single doses and time-averaged doses to specific accuracy thresholds (±5% to ±30%).

Results:

The percentage of single doses delivered outside accuracy thresholds of ±5%, ±10%, and ±20% were as follows: Animas OneTouch^® Ping^® (43.2%, 14.3%, and 1.8%, respectively), Roche Accu-Chek^® Combo (50.6%, 24.4%, and 5.5%), Medtronic Paradigm^® Revel^TM/Veo^TM (54.2%, 26.7%, and 6.6%), and Insulet OmniPod^® (79.1%, 60.5%, and 34.9%). For 30 min, 1 h, and 2 h averaging windows, the percentage of doses delivered outside a ±15% accuracy were as follows: OneTouch Ping (1.0%, 0.4%, and 0%, respectively), Accu-Chek Combo (4.2%, 3.5%, and 3.1%), Paradigm Revel/Veo (3.9%, 3.1%, and 2.2%), and OmniPod (33.9%, 19.9%, and 10.3%).

Conclusions:

This technical evaluation demonstrates significant differences in single-dose and averaged-dose accuracy among the insulin pumps tested. Differences in dose accuracy were most evident between the patch pump model and the group of durable pump models. Of the pumps studied, the Animas OneTouch Ping demonstrated the best single-dose and averaged-dose accuracy. Further research on the clinical relevance of these findings is warranted.     

Safety and efficacy of the Yukon Choice Flex sirolimus-eluting coronary stent in an all-comers population cohort

Aims

The use of biodegradable-polymer drug-eluting stents has been shown to provide favorable results when compared with durable polymer drug-eluting stents and long-term follow up data have recently shown significant reductions in terms of very late stent thrombosis.Aim of the present study was to assess the safety and efficacy profile of a novel biodegradable polymer DES, the Yukon Choice Flex sirolimus-eluting stent.

Methods

We report here the one-year clinical outcomes associated with the use of the Yukon Choice Flex sirolimus-eluting stent in an all-comers patient population. The present stent represents a further refinement of the stent platform tested in the ISAR TEST 3 and 4 randomized clinical trials. A total of 778 consecutive patients undergoing implantation of this stent were enrolled in the present observational study and prospectively followed for one year.

Results

The use of the Yukon Choice Flex stent in a patient population with complex coronary lesion morphology was associated with optimal immediate angiographic results. At one year follow up the rates of death, myocardial infarction, definite stent thrombosis and ischemia-driven target lesion revascularization were respectively 2.4%, 1.9%, 0.3% and 11.3%.

Conclusions

The use of the sirolimus-eluting biodegradable polymer Yukon Choice Flex stent in an all-comers population of patients with complex coronary artery disease is associated with a favorable safety and efficacy profile up to one year follow up.     

Long-term outcomes following coronary drug-eluting- and bare-metal-stent implantation

Background

Although drug-eluting stents (DES) reduce restenosis rates relative to bare-metal stents (BMS), recent reports have indicated that the use of DES may be associated with an increased risk of stent thrombosis. Our study focused on the effect of stent type on clinical outcomes in a “real world” setting.

Methods

889 patients undergoing percutaneous coronary intervention (PCI) with either DES (Cypher or Taxus; n = 490) or BMS (n = 399) were enrolled in a prospective single center registry. The outcome analysis covered a period of up to 3.2 years (mean 2.7 years ± 0.5 years) and was based on 65 deaths, 27 myocardial infarctions, 76 clinically driven target lesion revascularizations (TLR), and 15 angiographically confirmed cases of definite stent thrombosis and was adjusted for differences in baseline characteristics.

Results

In total 1277 stents (613 BMS and 664 DES) were implanted in 1215 lesions. Despite a significantly different unadjusted death rate (10.1% and 5.1% in BMS and DES patients, respectively; p < 0.05), the patient groups did not differ significantly in the risk of myocardial infarction during 2.7 years of follow-up. After adjustment for differences in baseline characteristics between groups, the difference in the cumulative incidence of death did not remain statistically significant (p = 0.22). Target lesion revascularizations occurred significantly less frequently in patients with DES compared to individuals after BMS implantation (5.9% and 11.8% in patients with DES and BMS, respectively; p < 0.05). The rate of angiographically confirmed stent thrombosis was 2.1% in patients with DES and 1.1% in BMS patients (p = 0.31).There was a significantly lower unadjusted event rate (including deaths, myocardial infarction, target lesion revascularization, and stent thrombosis) in patients with drug-eluting stents than in those with bare-metal stents (16.4% and 25.8%, respectively), with 9.4 fewer such events per 100 patients (unadjusted hazard ratio [HR], 0.64; 95% confidence interval [CI], 0.46 to 0.87). After adjustment, the relative risk for all outcome events in patients with drug-eluting stents was 0.79 (95% CI, 0.67 to 0.95). However, the adjusted relative risk for death and myocardial infarction did not differ significantly between groups (adjusted relative risk in patients with drug-eluting stents 0.94 (95% CI, 0.77 to 1.37)).

Conclusions

In this real-world population, the beneficial effect of first generation DES in reducing the need for new revascularization compared with BMS extends to more than 2.5 years without evidence of a worse safety profile. The minor risk of stent thrombosis and myocardial infarction within this period after implantation of DES seems unlikely to outweigh the benefit of these stents.     

Percutaneous Coronary Intervention using a Full Metal Jacket with Drug-eluting Stents: Major Adverse Cardiac Events at One Year

Background

The clinical benefit of percutaneous coronary intervention (PCI) for long coronary lesions is unclear; furthermore, concerns have been raised about its safety.

Objectives

To evaluate the predictors of major adverse cardiac events (MACE) associated with PCI using a full metal jacket (FMJ), defined as overlapping drug-eluting stents (DES) measuring > 60 mm in length, for very long lesions.

Methods

We enrolled 136 consecutive patients with long coronary lesions requiring FMJ in our single-center registry. The primary endpoint included the combined occurrence of all-cause death, myocardial infarction (MI), and target vessel revascularization (TVR). Demographic, clinical, angiographic, and procedural variables were evaluated using stepwise Cox regression analysis to determine independent predictors of outcome.

Results

The mean length of stent per lesion was 73.2 ± 12.3 mm and the mean reference vessel diameter was 2.9 ± 0.6 mm. Angiographic success was 96.3%. Freedom from MACE was 94.9% at 30 days and 85.3% at one year. At the one-year follow-up, the all-cause mortality rate was 3.7% (1.5% cardiac deaths), the MI rate was 3.7%, and the incidence of definite or probable stent thrombosis (ST) was 2.9%. Female gender [hazard ratio (HR), 4.40; 95% confidence interval (CI), 1.81-10.66; p = 0.001) and non-right coronary artery PCI (HR, 3.49; 95%CI, 1.42-8.59; p = 0,006) were independent predictors of MACE at one year. Freedom from adverse events at one year was higher in patients with stable angina who underwent PCI (HR, 0.33; 95%CI, 0.13-0.80; p = 0.014).

Conclusions

PCI using FMJ with DES for very long lesions was efficacious but associated with a high rate of ST at the one-year follow-up. However, the rate of cardiac mortality, nonprocedure-related MI, and MACE was relatively low. Target coronary vessel PCI, clinical presentation, and female gender are new contemporary clinical factors that appear to have adverse effects on the outcome of PCI using FMJ for long lesions.     

Comparison of liver parenchymal ablation and tissue necrosis in a cadaveric bovine model using the Harmonic Scalpel™, the LigaSure™, the Cavitron Ultrasonic Surgical Aspirator® and the Aquamantys® devices

Objectives

The amount of tissue that is ablated or necrosed at the line of parenchymal transection is of clinical significance in the interpretation of resection margin status following hepatic resection. The aim of this study was to define the extent of parenchymal ablation and necrosis in liver tissue using the Harmonic Scalpel™, the LigaSure™, the Cavitron Ultrasonic Surgical Aspirator® (CUSA®) and the Aquamantys® dissector ex vivo.

Methods

Mounted blocks of non-perfused bovine liver were transected using the Harmonic Scalpel™, LigaSure™, CUSA® and Aquamantys® devices. Outcome measures included parenchymal ablation (ablation band widths and weights) and tissue necrosis band widths along the line of transection. Each experiment was replicated five times.

Results

All devices were associated with parenchymal ablation (Harmonic Scalpel™, 4.73 ± 1.62 mm; LigaSure™, 4.55 ± 2.02 mm; CUSA®, 7.16 ± 2.87 mm; Aquamantys®, 4.75 ± 1.43 mm) and tissue necrosis (Harmonic Scalpel™, 1.07 ± 0.46 mm; LigaSure™, 1.36 ± 0.36 mm; CUSA®, 0.81 ± 0.21 mm; Aquamantys®, 0.81 ± 0.36 mm).

Conclusions

The Harmonic Scalpel™, LigaSure™, CUSA® and Aquamantys® devices were associated with bands of tissue loss along the hepatic parenchymal transection line in this benchtop cadaveric model. This should be taken into account in the interpretation of resection margin status following liver resection.