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Current stent delivery systems make primary stenting (stent placement without predilatation) possible, but few controlled trials have been performed to evaluate the success, safety, cost saving, and potential benefit of this approach in reducing late restenosis. The Comparison of PRE-Dilatation Versus Direct Stenting In Coronary Treatment using the Medtronic AVE S670 Coronary Stent System trial was a 399-patient study comparing results with the Medtronic-AVE S670 stent to objective performance criteria based on prior approved stents, with subrandomization to direct stenting versus stenting after balloon predilatation. Overall, results with the S670 stent showed excellent success and safety, with delivery success of 99%, a 14-day adverse event rate of 6.8% (including 6.5% non-Q-wave myocardial infarction), and favorable angiographic (20%) and clinical (12%) restenosis rates. Direct stenting was successful in 92% of cases, with a 99.5% secondary success rate including additional pretreatment of initially unsuccessful direct-stenting attempts, and no increase in complications. There were modest ( approximately 10%) savings in fluoroscopy time, contrast use, and a decrease in angioplasty balloon use (0.6 vs 1.3 balloons/case), but no reduction in clinical or angiographic restenosis. Patients treated later in the study, with a device that had less balloon extension beyond the edges of the stent, had slightly lower angiographic restenosis rates (19% vs 23%). In conclusion, the S670 stent showed excellent overall performance. Although direct stenting was safe and highly successful, it offered only modest cost savings, and no reduction in late restenosis compared with stenting after predilatation. [ABSTRACT FROM AUTHOR]

The assessment of left ventricular electromechanical activity using a novel, nonfluoroscopic 3-dimensional mapping system demonstrates considerable differences in electrical and mechanical activities within regions of myocardial infarction or ischemia. We sought to determine whether these changes correlate with indexes of myocardial perfusion, viability, or ischemia. A 12-segment comparative analysis was performed in 61 patients (45 men, 61 +/- 12 years old) with class III to IV angina, having reversible and/or fixed myocardial perfusion defects on single-photon emission computed tomographic perfusion imaging. A dual-isotope protocol was used, consisting of rest and 4-hour redistribution thallium images followed by adenosine technetium-99m sestamibi imaging. Average rest endocardial unipolar voltage (UpV) and local shortening (LS) mapping values were compared with visually derived perfusion scores. There was gradual and proportional reduction in regional UpV and LS in relation to thallium-201 uptake score at rest (p = 0.0001 and p = 0.0002, respectively) and redistribution studies (p = 0.0001 and p = 0.003, respectively). UpV > or = 7.4 mV and LS > or = 5.0% had a sensitivity of 78% and 65%, respectively, with a specificity of 68% and 67% for detecting viable myocardium. UpV values of 12.3 and 5.4 mV had 90% specificity and sensitivity, respectively, to predict viable tissue. UpV, but not LS, values differentiated between normal segments and those with adenosine-induced severe perfusion defects (11.8 +/- 5.3 vs 8.8 +/- 4.1 mV, p = 0.005). Catheter-based left ventricular assessment of electromechanical activity correlates with the degree of single-photon emission computed tomographic perfusion abnormality and can identify myocardial viability with a greater accuracy than myocardial ischemia. [ABSTRACT FROM AUTHOR]

The MULTI-LINK (ML) stent is a novel second generation coronary stent. The ACS MultiLink Stent Clinical Equivalence in De Novo Lesions Trial (ASCENT) randomized 1,040 patients with single, de novo native vessel lesions to treatment with the ML stent or the benchmark Palmaz-Schatz (PS) stent, to demonstrate that the ML stent was not inferior to (i.e., equivalent or better than) the PS stent in terms of target vessel failure by 9 months. Successful stent delivery was achieved in 98.8% versus 96.9% of patients, with a slightly lower postprocedural diameter stenosis (8% vs 10%, p = 0.04), and no difference in 30-day major adverse cardiac events (5.0% vs 6.5%) for the ML stent versus the PS stent. The primary end point of target vessel failure at 9 months was seen in 15.1% of ML-treated patients versus 16.7% of PS-treated patients, with the ML proving to be equal or superior to the PS stent (p <0.001 by test for equivalency). In a prespecified subset, angiographic restudy showed a nonsignificant trend for reduced ML restenosis (16.0% vs 22.1%). Thus, the ML stent showed excellent deliverability and acute results, with 9-month clinical and 6-month angiographic outcomes that were equivalent or better than the PS stent. [ABSTRACT FROM AUTHOR]

The NIR stent is a novel second generation tubular stent that was designed to overcome some of the limitations of the earlier Palmaz-Schatz (PS) stent design. The NIR Vascular Advanced North American (NIRVANA) trial randomized 849 patients with single coronary lesions to treatment with the NIR stent or the PS stent. The study was an "equivalency" trial, designed to demonstrate that the NIR stent was not inferior to (i.e., equivalent or better than) the PS stent, for the primary end point of target vessel failure (defined as death, myocardial infarction, or target vessel revascularization) by 9 months. Successful stent delivery was achieved in 100% versus 98.8%, respectively, with a slightly lower postprocedural diameter stenosis (7% vs. 9%, p = 0.04) after NIR and PS stent placement, respectively. Major adverse cardiac events (death, myocardial infarction, repeat target lesion revascularization) were not different at 30 days (4.3% vs. 4.4%). The primary end point of target vessel failure at 9 months was seen in 16.0% of NIR versus 17.2% of PS patients, with the NIR proving to be equal or superior to the PS stent (p <0.001 by test for equivalency). Angiographic restudy in 71% of a prespecified cohort showed no significant difference in restenosis (19.3% vs 22.4%). Thus, the NIR stent showed excellent deliverability with slightly better acute angiographic results and equivalent or better 9-month target vessel failure rate when compared with the PS stent. [ABSTRACT FROM AUTHOR]

Although patients with end-stage renal disease (ESRD) are at high risk for restenosis that requires repeat revascularization after balloon angioplasty, their restenosis rate after coronary stenting is still unknown. Over a 4-year period, we performed coronary stenting on 40 lesions in 34 patients with ESRD. We compared these lesions with 80 lesions from patients without renal disease who underwent coronary stenting in the STARS and WINS clinical trials, matched for treatment site, diabetes, lesion length, and reference vessel diameter. Quantitative coronary angiography was performed on all lesions and clinical outcomes were assessed at 9-month follow-up. Clinical and angiographic characteristics were well matched between the 2 groups and acute clinical success rates were similar. Despite comparable initial angiographic results over the 9-month follow-up period, repeat target lesion revascularization was twice as frequent in the ESRD group compared with the control group (35% vs 16%, p <0.05). After adjusting for differences in postprocedural minimum lumen diameter and other angiographic and clinical characteristics, ESRD remained the most important predictor of late target lesion revascularization (relative risk = 2.3, p = 0.04). In addition, overall 9-month mortality was higher for ESRD patients than for the control population (18% vs 2%, p <0.01). Thus, despite similar angiographic results, patients with ESRD are at higher risk for target lesion revascularization after coronary stenting than controls. Nonetheless, most patients with ESRD do not develop restenosis after stent placement, suggesting an important role for stenting in the management of this challenging population. [ABSTRACT FROM AUTHOR]

The cumulative experience of 4 clinical trials using the MULTI-LINK coronary stent design was analyzed. Multivariable logistic regression identified postprocedure in-stent minimum lumen diameter (p = 0.0001), stent length (p = 0.0038), smoking (p = 0.0105). and diabetes (p = 0.0803) as the most important predictors of in-stent restenosis at late (6- to 9-month) angiographic follow-up. [ABSTRACT FROM AUTHOR]

Despite advances in other aspects of cardiac catheterization, manual or mechanical compression followed by 4 to 8 hours of bed rest remains the mainstay of postprocedural femoral access site management. Suture-mediated closure may prove to be an effective alternative, offering earlier sheath removal and ambulation, and potentially a reduction in hemorrhagic complications. The Suture To Ambulate aNd Discharge trial (STAND I) evaluated the 6Fr Techstar device in 200 patients undergoing diagnostic procedures, with successful hemostasis achieved in 99% of patients (94% with suture closure only) in a median of 13 minutes, and 1% major complications. STAND II randomized 515 patients undergoing diagnostic or interventional procedures to use of the 8Fr or 10Fr Prostar-Plus device versus traditional compression. Successful suture-mediated hemostasis was achieved in 97.6% of patients (91.2% by the device alone) compared with 98.9% of patients with compression (p = NS). Major complication rates were 2.4% and 1.1%, and met the Blackwelder's test for equivalency (p <0.05). Median time to hemostasis (19 vs 243 minutes, p <0.01) and time to ambulation (3.9 vs 14.8 hours, p <0.01) were significantly shorter for suture-mediated closure. Suture-mediated closure of the arterial puncture site thus affords reliable immediate hemostasis and shortens the time to ambulation without significantly increasing the risk of local complications. [ABSTRACT FROM AUTHOR]

The influence of vessel size on clinical and angiographic outcomes after new device angioplasty has not been well documented. We reviewed clinical and angiographic outcomes of 2,044 patients undergoing new device angioplasty of native vessels enrolled in the New Approaches to Coronary Interventions (NACI) Registry. Quantitative angiography was performed using standard methods. Patients were divided into 3 groups according to reference vessel diameter (RVD) (<2.75, 2.75 to 3.25, and >3.25 mm). Patients with the smallest vessels had a higher incidence of diabetes (26% vs. 16%, p<0.01), multivessel disease (50% vs. 45%, p<0.01), left anterior descending coronary artery disease (61% vs. 39% p<0.01), and in general, more severe baseline lesion characteristics than patients with larger (>3.25 mm) vessels. Absolute baseline and final minimal lumen diameter (MLD) was also smaller in patients with RVD <2.75 mm despite similar final percent diameter stenosis. Although in-hospital events were similar, patients who underwent interventions in vessels <2.75 mm had an increased incidence of death (p<0.01), surgical revascularization (p<0.05), and target lesion revascularization (TLR) (p<0.01) at 1 year. Multivariate analysis by vessel size showed a stepwise increase in the risk of TLR by 1 year in patients with the smaller RVD (p = 0.0001) and the combined end point of 1 year death/Q wave-myocardial infarction/TLR (p = 0.02). Thus, despite similar early clinical events among patients undergoing new device angioplasty, patients who underwent treatment of smaller vessels had a significantly increased risk of major adverse clinical events and particularly TLR by 1 year after new device angioplasty of native coronary arteries. [ABSTRACT FROM AUTHOR]

Although substantial intersystem variability has been shown among several commercially available quantitative angiographic (QA) analysis algorithms, no previous study has compared the angiographic findings using 2 different QA systems performed at the same central angiographic laboratory. The purpose of this study was to compare the early and late QA results obtained with the CMS (MEDIS) and ARTREK (ImageComm) QA systems in the Balloon versus Optimal Atherectomy Trial. Directional atherectomy (n = 496) or balloon angioplasty (n = 490) was performed in 986 patients; late QA follow-up was available in 767 patients (77.7%). QA analysis was performed by 2 independent observers using the CMS and ARTREK systems. Correlation between the 2 QA systems for baseline measurements was good (Pearson's R = 0.78), although the CMS system resulted in larger baseline reference diameter (RD) (3.22 +/- 0.45 vs 3.07 +/- 0.40 mm; p <0.0001) and baseline minimal lumen diameters (MLD) (1.05 +/- 0.35 vs 0.92 +/- 0.32; mm p <0.0001) than the ARTREK system. The final and follow-up RD (+0.17 and +0.11 mm, respectively) were also larger using the CMS system. In contrast, the final and follow-up measurements of MLD and percent diameter stenosis were not significantly different using the 2 QA systems. The QA system did not affect the ability to detect a difference in restenosis rates (>50% follow-up diameter stenosis) between the 2 treatment groups (CMS, directional atherectomy [31.8%]; balloon angioplasty [40.5%]; p = 0.013 and ARTREK, directional atherectomy [33.9%], balloon angioplasty [41.3%]; p = 0.036). Only lesion irregularity contributed to the difference in baseline measurements of MLD and percent diameter stenosis. We conclude that important differences in measurements of RD, baseline MLD, and percent diameter stenosis were noted using the CMS and ARTREK systems. Both systems, however, were able to detect a treatment benefit associated with directional atherectomy in BOAT. The comparability of other angiographic systems will require similar evaluation in other studies. [ABSTRACT FROM AUTHOR]

Previous studies have shown a high rate of repeat intervention after treating diffuse in-stent restenosis with percutaneous transluminal coronary angioplasty (PTCA) alone. It is not clear whether debulking with atherectomy is more effective in this condition. Between January 1994 and February 1997, we treated 60 consecutive patients with diffuse in-stent restenosis of a native coronary artery using conventional PTCA (n=30) or debulking (with rotational or directional atherectomy) plus adjunctive PTCA (n=30). Paired angiograms were analyzed by quantitative angiography, and clinical follow-up was obtained in all patients at 1 month, 6 months, and 1 year after revascularization. The mean lesion lengths were 13.5+/-8.3 and 18.4+/-13.2 mm in the debulking and PTCA groups, respectively (p=0.09). Acute procedural success was 100% in both cohorts, with no major complications in either group. Treatment with atherectomy plus adjunctive PTCA resulted in lower postprocedure stenoses (18+/-10 vs 26+/-13%, p=0.01) than treatment with balloon angioplasty alone. At 1-year follow-up, repeat target vessel revascularization was required in 28% of patients in the debulking group compared with 46% in the PTCA group (p=0.18). Independent predictors of the need for repeat target vessel revascularization were longer lesion lengths, diabetes mellitus, and smaller postprocedure lumen diameter. Thus, the strategy of atherectomy and adjunctive PTCA for diffuse in-stent restenosis is safe, improves acute angiographic results compared with PTCA alone, and may decrease the need for target vessel revascularization. [ABSTRACT FROM AUTHOR]

We present the completed 1-year follow-up results of the original Stent Restenosis Study (STRESS I), in which 407 patients with symptomatic ischemic heart disease and new lesions of the native coronary circulation were randomly assigned to treatment with either the Palmaz-Schatz coronary stent or conventional percutaneous transluminal coronary angioplasty (PTCA). The present study compares the safety of elective stenting to balloon angioplasty (PTCA) in terms of freedom from clinical events up to 1 year after treatment. Patients were enrolled and treated from January 1991 through February 1993, and follow-up data were collected and verified until July 1995. Ninety-seven percent of all patients had complete follow-up (deceased or alive with known clinical status) beyond 8 months, and 94% beyond 11 months. Anginal status between 9 to 15 months postprocedure was available for 78% of patients. At 1 year, 154 patients (75%) assigned to stent implantation and 141 (70%) to PTCA were free of all clinical events (death, myocardial infarction, or any revascularization procedure), and 162 stent patients (79%) and 149 PTCA patients (74%) were free from death, myocardial infarction, or target lesion revascularization. Symptom-driven target lesion revascularization occurred in 12% of the stent group versus 17% of the PTCA group. None of these differences in clinical events was statistically significant. Only 2 patients in the stent group and 7 in the PTCA group had a first event after 239 days, and freedom from angina at 1 year was reported in equal frequency in both groups (84%). There appear to be no late adverse effects of stent implantation. However, these results are limited by low statistical power, narrow patient selection, and the anticoagulation regimen used in the early experience with this device. [ABSTRACT FROM AUTHOR]