Quality of reporting internal and external validity data from randomized controlled trials evaluating stents for percutaneous coronary intervention. Coronary stenting after rotational atherectomy in diffuse lesions of the small coronary artery: comparison with balloon angioplasty before stenting. Systematic versus selective stent placement after superficial femoral artery balloon angioplasty: a multicenter prospective randomized study. A prospective randomized trial comparing stenting to internal mammary artery grafting for proximal, isolated de novo left anterior coronary artery stenosis: the SIMA trial. Stenting vs Internal Mammary Artery. High-dose 7-hexanoyltaxol-eluting stent with polymer sleeves for coronary revascularization: one-year results from the SCORE randomized trial. Randomized study to assess the effectiveness of slow- and moderate-release polymer-based paclitaxel-eluting stents for coronary artery lesions. A prospective randomised study of "covered" versus "uncovered" diamond stents for the management of distal malignant biliary obstruction. Use of continuous quality improvement to increase use of process measures in patients undergoing coronary artery bypass graft surgery: a randomized controlled trial. Alert for increased long-term follow-up after carotid artery stenting: results of a prospective, randomized, single-center trial of carotid artery stenting vs carotid endarterectomy.
Stents are commonly used to treat patients with coronary artery disease. However, the quality of reporting internal and external validity data in published reports of randomised controlled trials (RCTs) of stents has never been assessed.The objective of our study was to evaluate the quality of reporting internal and external validity data in published reports of RCTs assessing the stents for percutaneous coronary interventions.
                A systematic literature review was conducted. Reports of RCTs assessing stents for percutaneous coronary interventions indexed in MEDLINE and the Cochrane Central Register of Controlled Trials and published between January 2003 and September 2008 were selected. A standardized abstraction form was used to extract data. All analyses were adjusted for the effect of clustering articles by journal.
                132 articles were analyzed. The generation of the allocation sequence was adequate in 58.3% of the reports; treatment allocation was concealed in 34.8%. Adequate blinding was reported in one-fifth of the reports. An intention-to-treat analysis was described in 79.5%. The main outcome was a surrogate angiographic endpoint in 47.0%. The volume of interventions per center was described in two reports. Operator expertise was described in five (3.8%) reports. The quality of reporting was better in journals with high impact factors and in journals endorsing the CONSORT statement.
                The current reporting of results of RCTs testing stents needs to be improved to allow readers to appraise the risk of bias and the applicability of the results. The purpose of this randomized trial was to evaluate the role of debulking and balloon predilation on acute and long-term results of stent implantation in diffuse stenosis of small vessels. Patients with symptomatic diffuse stenosis of the native left anterior descending coronary artery between 2 and 2.9 mm in size were randomly assigned to rotational atherectomy (group I, n = 21) or balloon dilation (group II, n = 20) before stenting. The primary end point of the study was the incidence of angiographic restenosis at follow-up; adverse clinical events, such as death, myocardial infarction, stroke, or target vessel revascularization, were assessed as secondary end points. Acute gain was significantly greater in group I than in group II (p = 0.038), but net gain at follow-up was similar in both groups (p = 0.24). There was no significant difference in angiographic restenosis rate (33.3% vs 31.3%, p = 0.80), target vessel revascularization (23.8% vs 15%, p = 0.21) or 1-year event-free survival rate (72.8% vs 84.6%, p = 0.28). In conclusion, rotational atherectomy before stenting showed no additional benefit over balloon dilation with stenting in the management of diffuse lesions in small coronary vessels. Outcome with selective or systematic stenting with the Palmaz vascular stent was compared in patients with limb-threatening ischemia or persistent disabling claudication despite medical therapy, with less than 7 cm stenosis or occlusion of the superficial femoral artery.
                This was a multicenter prospective randomized trial with centralized allocation of treatment and independent review of vascular events. The primary end point was presence of more than 50% stenosis at 1-year angiographic follow-up. Secondary end points were survival; occurrence of vascular events in the treated leg; and number of failed procedures, defined as more than 50% stenosis or death at 1 year.
                Two hundred twenty-seven patients were enrolled in the study, 112 in the selective stent group, and 115 in the systematic stent group. Seventeen patients (15%) in the selective stent group received a stent after suboptimal results of percutaneous transluminal angioplasty. Angiograms for 140 patients were available at 1-year follow-up and demonstrated no statistical difference between the two groups; more than 50% stenosis of the dilated site was noted in 21 of 65 patients (32,3%) in the selective stent group and 26 of 75 patients (34.7%) in the systematic stent group (P =.85, Fisher exact test). Survival in the percutaneous transluminal angioplasty and stent groups was, respectively, 92% and 96% at 1 year, 89% and 93% at 2 years, and 82% and 80% at 4 years (P =.40, log-rank test). Survival free of new vascular events in the treated limb was 77% and 65% at 1 year, 70% and 53% at 2 years, and 57% and 44% at 4 years (P =.017, log-rank test). Number of failed procedures at 1 year was 29 of 86 (33%) and 30 of 89 (34%) (P = 0.9).
                Systematic stenting of short stenosis or occlusion of the superficial femoral artery is not justified. Palmaz vascular stent placement should be reserved for use in patients with suboptimal results of balloon angioplasty. To compare coronary artery bypass grafting (CABG) with percutaneous transluminal coronary angioplasty (PTCA) in patients with proximal, isolated de novo left anterior descending coronary artery disease and left ventricular ejection fraction of 45%.
                In the multicenter Stenting vs Internal Mammary Artery (SIMA) study, patients were randomly assigned to PTCA and stent implantation or to CABG (using the internal mammary artery). The primary clinical composite end point was event-free survival, including death, myocardial infarction, and the need for additional revascularization. Secondary end points were functional class, antianginal treatment, and quality of life. Analyses were by intention to treat.
                Of 123 patients who accepted randomization, 59 underwent CABG, and 62 were treated with stent implantation (2 patients were excluded because of protocol violation). At a mean +/- SD follow-up of 2.4+/-0.9 years, a primary end point had occurred in 19 patients (31%) in the stent group and in 4 (7%) in the CABG group (P<.001). This significant difference in clinical outcome is due to a higher incidence of additional revascularization in the stent group, the incidence of death and myocardial infarction being similar (7% vs 7%, respectively; P=.90). The functional class, need for antianginal drug, and quality-of-life assessment showed no significant differences.
                Both stent implantation and CABG are safe and highly effective treatments to relieve symptoms in patients with isolated, proximal left anterior descending coronary artery stenosis. Both are associated with a low and comparable incidence of death and myocardial infarction. However, similar to PTCA alone, a percutaneous approach using elective stent placement remains hampered by a higher need for repeated intervention because of restenosis. The Study to COmpare REstenosis Rate between QueST and QuaDDS-QP2 (SCORE) trial was a multicenter, randomized, open-label trial comparing the safety and performance of 13- and 17-mm QuaDDS stents (n = 126) (Quanam Medical Corp., Santa Clara, California/Boston Scientific Corp., Natick, Massachusetts) versus uncoated control stents (n = 140) in focal, de novo coronary lesions.
                The pioneering drug-delivery QuaDDS stent used four to six acrylate polymer sleeves, each loaded with 800 microg of the paclitaxel derivative 7-hexanoyltaxol.
                Clinical end points were assessed at 1, 6, and 12 months post procedure. Quantitative coronary angiography and intravascular ultrasound were performed post procedure and at six-month follow-up.
                In the QuaDDS group, early stent thrombosis and myocardial infarction (MI) rates were significantly higher, leading to premature cessation of enrollment. For the QuaDDS group, the stent thrombosis rate increased from 3.2% to 10.3% between 1 and 12 months, associated with increased non-Q-wave MI and death rates. The angiographic restenosis rate at six months was reduced from 32.7% (control) to 7.4% (p < 0.0001). However, the primary end point was not met with six-month target vessel revascularization (TVR) rate as well as the composite major adverse cardiac event rates (cardiac death, MI, and TVR) comparable between groups.
                Despite angiographic indications of potential anti-restenotic benefit, increased rates of stent thrombosis, MI, and cardiac death associated with the QuaDDS stent show an unacceptable safety profile. Early clinical studies demonstrated the feasibility of local paclitaxel delivery in reducing restenosis after treatment of de novo coronary lesions in small patient populations.
                We conducted a randomized, double-blind trial of 536 patients at 38 medical centers evaluating slow-release (SR) and moderate-release (MR) formulations of a polymer-based paclitaxel-eluting stent (TAXUS) for revascularization of single, primary lesions in native coronary arteries. Cohort I compared TAXUS-SR with control stents, and Cohort II compared TAXUS-MR with a second control group. The primary end point was 6-month percent in-stent net volume obstruction measured by intravascular ultrasound. Secondary end points were 6-month angiographic restenosis and 6- and 12-month incidence of major adverse cardiac events, a composite of cardiac death, myocardial infarction, and repeat revascularization. At 6 months, percent net volume obstruction within the stent was significantly lower for TAXUS stents (7.9% SR and 7.8% MR) than for respective controls (23.2% and 20.5%; P<0.0001 for both). This corresponded with a reduction in angiographic restenosis from 17.9% to 2.3% in the SR cohort (P<0.0001) and from 20.2% to 4.7% in the MR cohort (P=0.0002). The incidence of major adverse cardiac events at 12 months was significantly lower (P=0.0192) in the TAXUS-SR (10.9%) and TAXUS-MR (9.9%) groups than in controls (22.0% and 21.4%, respectively), predominantly because of a significant reduction in repeat revascularization of the target lesion in TAXUS-treated patients.
                Compared with a bare metal stent, paclitaxel-eluting stents reduced in-stent neointimal formation and restenosis and improved 12-month clinical outcome of patients with single de novo coronary lesions. Covered self-expandable metal stents (EMS) were recently developed to overcome tumour ingrowth in conventional EMS. However, supporting evidence for the efficacy of covered EMS is lacking.
                We enrolled 112 patients with unresectable distal biliary malignancies. They were randomly assigned to polyurethane covered (n = 57) or original diamond stent (n = 55).
                Stent occlusion occurred in eight patients (14%) after a mean of 304 days in the covered group, and in 21 patients (38%) after a mean of 166 days in the uncovered group. The incidence of covered EMS occlusion was significantly lower than that of uncovered EMS (p = 0.0032). The cumulative stent patency of covered stents was significantly higher than that of uncovered stents (p = 0.0066). No tumour ingrowth occurred in the covered group while it was observed in 15 patients in the uncovered group. In subgroup analysis, the cumulative patency of the covered EMS was significantly higher in pancreatic cancer (p = 0.0363) and metastatic lymph nodes (p = 0.0354). There was no significant difference in survival between the two groups. Acute cholecystitis was observed in two of the covered group and in none of the uncovered group. Mild pancreatitis occurred in five of the covered group and in one of the uncovered group.
                Covered diamond stents successfully prevented tumour ingrowth and were significantly superior to uncovered stents for the treatment of patients with distal malignant biliary obstruction. However, careful attention must be paid to complications specific to covered self-expandable metal stents, such as acute cholecystitis and pancreatitis. A rigorous evaluation of continuous quality improvement (CQI) in medical practice has not been carried out on a national scale.
                To test whether low-intensity CQI interventions can be used to speed the national adoption of 2 coronary artery bypass graft (CABG) surgery process-of-care measures: preoperative beta-blockade therapy and internal mammary artery (IMA) grafting in patients 75 years or older.
                Three hundred fifty-nine academic and nonacademic hospitals (treating 267 917 patients using CABG surgery) participating in the Society of Thoracic Surgeons National Cardiac Database between January 2000 and July 2002 were randomized to a control arm or to 1 of 2 groups that used CQI interventions designed to increase use of the process-of-care measures.
                Each intervention group received measure-specific information, including a call to action to a physician leader; educational products; and periodic longitudinal, nationally benchmarked, site-specific feedback.
                Differential incorporation of the targeted care processes into practice at the intervention sites vs the control sites, assessed by measuring preintervention (January-December 2000)/postintervention (January 2001-July 2002) site differences and by using a hierarchical patient-level analysis.
                From January 2000 to July 2002, use of both process measures increased nationally (beta-blockade, 60.0%-65.6%; IMA grafting, 76.2%-82.8%). Use of beta-blockade increased significantly more at beta-blockade intervention sites (7.3% [SD, 12.8%]) vs control sites (3.6% [SD, 11.5%]) in the preintervention/postintervention (P =.04) and hierarchical analyses (P<.001). Use of IMA grafting also tended to increase at IMA intervention sites (8.7% [SD, 17.5%]) vs control sites (5.4% [SD,15.8%]) (P =.20 and P =.11 for preintervention/postintervention and hierarchical analyses, respectively). Both interventions tended to have more impact at lower-volume CABG sites (for interaction: P =.04 for beta-blockade; P =.02 for IMA grafting).
                A multifaceted, physician-led, low-intensity CQI effort can improve the adoption of care processes into national practice within the context of a medical specialty society infrastructure. Carotid endarterectomy (CEA) has been shown to be effective in stroke prevention for patients with symptomatic or asymptomatic carotid artery stenosis. Although several prospective randomized trials indicate that carotid artery stenting (CAS) is an alternative but not superior treatment modality, there is still a significant lack of long-term data comparing CAS with CEA. This study presents long-term results of a prospective, randomized, single-center trial.
                Between August 1999 and April 2002, 87 patients with a symptomatic high-grade internal carotid artery stenosis (>70%) were randomized to CAS or CEA. After a median observation time of 66 +/- 14.2 months (CAS) and 64 +/- 12.1 months (CEA), 42 patients in each group were re-evaluated retrospectively by clinical examination and documentation of neurologic events. Duplex ultrasound imaging was performed in 61 patients (32 CAS, 29 CEA), and patients with restenosis >70% were re-evaluated by angiography.
                During the observation period, 23 patients (25.2%) died (10 CAS, 13 CEA), and three were lost to follow up. The incidence of strokes was higher after CAS, with four strokes in 42 CAS patients vs none in 42 CEA patients. One transient ischemic attack occurred in each group. A significantly higher rate of restenosis >70% (6 of 32 vs 0 of 29) occurred after CAS compared with CEA. Five of 32 CAS patients (15.6%) presented with high-grade (>70%) restenosis as an indication for secondary intervention or surgical stent removal, and three presented with neurologic symptoms. No CEA patients required reintervention (P < .05 vs CAS). A medium-grade (<70%) restenosis was detected in eight of 32 CAS patients (25%) and in one of 29 CEA patients (3.4%). In five of 32 CAS (15.6%) and three of 29 CEA patients (10.3%), a high-grade stenosis of the contralateral carotid artery was observed and treated during the observation period.
                The long-term results of this prospective, randomized, single-center study revealed a high incidence of relevant restenosis and neurologic symptoms after CAS. CEA seems to be superior to CAS concerning the development of restenosis and significant prevention of stroke. However, the long-term results of the ongoing multicenter trials have to be awaited for a final conclusion.
This systematic review suggests that the use of external stents following pancreaticoduodenectomy may be beneficial. However, only a limited number of RCTs with rather small sample sizes were available. Further RCTs on the use of stents after pancreaticoduodenectomy are warranted.