Direct coronary stenting versus stenting with balloon pre-dilation: immediate and follow-up results of a multicentre, prospective, randomized study. The DISCO trial. DIrect Stenting of COronary Arteries.

AIMS: To assess the safety of direct coronary stenting, its influence on costs, duration of the procedure, radiation exposure, clinical outcome and angiographic restenosis. METHODS AND RESULTS: We randomized 416 patients (446 lesions) to direct stent implant or stent implant following balloon pre-dilation. Patients >75 years old, heavily calcified lesions, bifurcations, total occlusions, left main lesions and very tortuous vessels were excluded. Direct stenting was successful in 217/224 lesions (96.8%). No single loss or embolization of the stent occurred. All stents in the group with pre-dilation were effectively deployed. The immediate post-procedure angiographic results were similar with both techniques. Fluoroscopy and procedural time were significantly lower in direct stenting (6.4+/-0.3 and 21+/-0.9 min) than in pre-dilated stenting (9.1+/-0.4 and 27.5+/-1.1 min) (P>0.001). Major adverse cardiac events during hospitalization were one in direct and four in pre-dilated stenting (P=0.05) but there were no significant differences at follow-ups at 1, 6 and 12 months between the two groups. Angiographic reevaluation at 6 months was performed in 94% of the cases. Restenosis rate was 16.5% in direct stenting and 14.3% in pre-dilated stenting (P=ns). CONCLUSIONS: Direct stenting is as safe as pre-dilated stenting in selected coronary lesions. Acute angiographic results are similar but procedural costs, duration of the procedure and radiation exposure are lower in direct stenting. Overall success rate, mid-term clinical outcome and restenosis are similar with both techniques.     

The SIRIUS-DIRECT trial: a multi-center study of direct stenting using the sirolimus-eluting stent in patients with de novo native coronary artery lesions.

OBJECTIVE: To assess the safety and efficacy of direct stenting using the sirolimus-eluting BX Velocitytrade mark stent in patients with coronary lesions. BACKGROUND: Although direct coronary stenting has become a widespread practice, there have been no systematic assessments of direct stenting with drug-eluting stents. METHODS: Total of 225 patients with identical inclusion and exclusion criteria as the original SIRIUS trial were enrolled in this prospective single-arm study. They were compared in a no-inferiority design with 412 similar patients from the SIRIUS trial who had sirolimus-eluting stents deployed after predilatation and were preassigned to angiographic follow-up evaluation. RESULTS: Direct stenting was successful in 85.8% of the patients. Compared with the predilatation group, direct stenting was associated with shorter median procedure duration (33 min vs. 45 min, P < 0.001). Angiographic follow-up at 8 months revealed similar late loss (in-stent-0.19 +/- 0.47 mm vs. 0.17 +/- 0.44 mm, and in-lesion-0.23 +/- 0.41 mm vs. 0.24 +/- 0.47 mm) and similar frequency of binary restenosis (in-stent-4.6% vs. 3.2% and in-lesion-6.1% vs. 8.9%) between the two treatment strategies. However, stent-edge restenosis was lower with direct stenting than in the predilatation control group (2.1% vs. 6.9%, P = 0.02). At 12-months, there were no significant differences in target lesion revascularization (3.7% vs. 5.1%, P = ns) or composite major adverse cardiac events (7.0% vs. 8.3%, P = ns). CONCLUSIONS: In patients similar to those treated in the SIRIUS trial, direct stenting using sirolimus-eluting stents achieves excellent short- and long-term clinical and angiographic results with shorter procedure time and less frequent stent edge restenosis compared with predilation stent implantation techniques.     

Direct stenting versus predilatation and stenting technique when using paclitaxel-eluting stents

Direct stenting without predilatation is a well-defined, feasible method with bare metal stents. Direct stenting has also been shown to be safe and feasible with drug-eluting stents, however, there is much less evidence with this type of device when compared with bare metal stents. Three hundred and sixty-four coronary lesions in 257 consecutive patients (mean age, 57.4 +/- 9.8 years; 63 women) who had undergone elective stenting either with or without predilatation via a paclitaxel-eluting stent between March 2003 and March 2006 were retrospectively analyzed. Quantitative coronary angiography analysis was compared between the two groups of procedures; stenting with predilatation and direct stenting. All procedures were uneventful. No deaths occurred during the follow-up period. Direct stenting when compared with the predilatation technique, significantly decreased both procedure time (32.1 +/- 17.9 minute versus 41.2 +/- 18.6 minute, P < 0.0001) and fluoroscopy time (10.6 +/- 7.8 minute versus 15.5 +/- 7.6 minute, P < 0.0001). There was no difference in quantitative analysis parameters of coronary angiography during follow-up or the rates of stent thrombosis and restenosis. Direct stenting seems to be as feasible and safe as conventional predilatation and stenting in selected cases. Direct stenting seems to decrease procedural time and radiation exposure without any negative effect on quantitative analysis parameters of coronary angiography with approximately a one-year follow-up period.     

Expansion of the Multilink-Tristar stent after direct implantation and predilatation: comparison of clinical,angiography and intravascular ultrasound parameters

Coronary stenting has become the primary therapeutic option for many coronary lesions. As opposed to conventional stenting the advantages of direct stenting are a reduction of procedural time, radiation exposure and costs. However, data about the incidence of in-stent restenosis are so far not available. It was the aim of this prospective study to compare the expansion of the Multilink stent after direct stenting and predilatation by quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS). Between January 2000 and June 2001, 82 patients were assigned to direct stenting (46 lesions) or predilatation (40 lesions) in lesions of coronary arteries > 3 mm. The procedural success rate was 92% in patients undergoing direct stenting. The baseline clinical characteristics were similar in both groups. The comparison of the angiographic data shows that direct stenting was performed in lesions with a lower degree of stenosis (71 +/- 12% vs 79 +/- 11%, p = 0.01) and that significantly shorter stents were used (14.4 +/- 3.0 vs 17.8 +/- 4.1 mm, p = 0.0007). The mean stenosis length was not significantly different in either group (10.5 +/- 3.4 vs 11.7 +/- 4.3 mm, n.s.). The QCA data after stent implantation show no differences of either implantation technique. Stent expansion was assessed by IVUS estimation of the proximal, distal and minimal in stent area. The minimal in-stent area (9.53 +/- 3.23, mm2 vs 8.65 +/- 1.96 mm2, n.s.) and the stent symmetry index (0.88 vs 0.88 n.s.) were not different in either patient group. These results indicate that in this subset of selected coronary lesions > 3 mm, elective stent implantation with and without predilatation effectively can achieve comparable stent expansion as assessed by QCA and IVUS. In comparison to conventional stent implantation stents, which were implanted without predilatation, were significantly shorter to cover the same lesion length.     

Comparison of direct stenting versus stenting with predilation for the treatment of selected coronary narrowings.

Direct stenting may reduce costs, procedure times, and injury to the vessel wall, positively influencing acute and late results. This study was designed to demonstrate 6-month clinical outcome equivalence between direct and standard stenting techniques. Four hundred eleven patients (425 lesions) were randomized in 7 sites to undergo direct (210 patients, 216 lesions) or conventional (201 patients, 209 lesions) stent implantation. Lesions with severe calcification were excluded. Angiographic success rate was 100% in the direct stent group (2.8% requiring balloon predilation) and 98.6% in the predilation group (p = 0.12). Direct stenting was associated with decreased use of balloons (0.15 vs 1.09 balloons/lesion treated) and with a trend toward a reduction of procedure time (22.7 +/- 15.0 vs 25.6 +/- 18.2 minutes; p = 0.073). Fluoroscopy time and contrast volume were not different between groups. At 6-month follow-up, the incidences of death (direct [1.4%] vs predilation [2.5%]), myocardial infarction (5.3% vs 5.0%), and target vessel revascularization (8.2% vs 10.5%) were similar in both groups. Major adverse cardiac event-free survival rate was 87.5% for those who underwent the direct stent technique and 85.5% for patients who underwent predilation (p = 0.0002 for equivalence). In conclusion, direct stenting is at least equivalent to the standard technique in terms of 6-month clinical outcomes when performed on selected coronary lesions without significant calcification. This strategy is associated with decreased use of balloons, but, in general, does not significantly reduce procedure times.     

Angiographic restenosis after myocardial bridge stenting

Data on restenosis after stent implantation in myocardial bridges (MB) are very limited. Six-month angiographic results for 12 symptomatic patients who underwent stent implantation for myocardial bridges were compared retrospectively with those of 39 patients who underwent direct stent implantation for de novo atherosclerotic lesions in the left anterior descending artery. Diameter stenosis decreased from 69 +/- 8% to 4 +/- 5% in the MB group and from 79 +/- 8% to 7 +/- 6% in the control group after stent deployment. Systolic narrowing was abolished in all patients with MB. In follow-up, quantitative angiography revealed late loss of 1.8 +/- 1.3 mm in the MB group and 0.9 +/- 0.9 mm in the control group (P = 0.025). The in-stent restenosis rate was also higher in the MB group compared to the control group (67% versus 28%; P = 0.037). Despite favorable immediate results, stent implantation in MBs may not be promising because of the higher in-stent restenosis rate compared to stenting in de novo atherosclerotic lesions.     

Multicenter randomized comparison of direct vs. conventional stenting: the DIRECTO trial.

With conventional stenting, predilatation frequently induces dissections that require deploying stents longer than originally planned. To assess whether direct stenting is safe and may prevent dissections and reduce the length of stents implanted, we conducted a randomized study comparing direct (n = 73) and conventional (n = 78) stenting. Direct stenting was successful in 89% of cases, 11% crossed over to predilation without complications. Dissections occurred more frequently in conventional stenting group (10.3% vs. 1.4%; P = 0.034), but did not translate to a significant stent length difference (16.31 +/- 7.6 vs. 15.31 +/- 5.5; P = NS). Periprocedure creatine kinase elevation and number of balloons utilized were lower with direct stenting.     

Effectiveness of "direct" stenting without balloon predilatation (from the Multilink Tetra Randomised European Direct Stent Study [TRENDS])

The purpose of the TRENDS trial was to assess the safety, efficacy, and cost effectiveness of a no-predilatation ("direct") stenting strategy in the treatment of de novo native coronary artery lesions using the Multilink Tetra stent system. In this multicenter, prospective clinical trial, 1,000 patients were randomized (1:1) to receive a Multilink Tetra stent with or without balloon predilatation. The primary outcome measurement was major adverse cardiac events (MACEs) at 30 days; secondary end points included resource utilization (including procedural duration, equipment use, and length of hospital stay), MACEs, and angiographic binary restenosis at 180 days. In the predilatation group, 587 stents were implanted in 499 patients; in the direct group, 579 stents were implanted in 501 patients. In the direct group, stents in 31 lesions (5.7%) required predilatation and multivariate analysis identified calcification (odds ratio 5.81), angulation (odds ratio 5.34), and preprocedural minimal lumen diameter (odds ratio 0.09) as direct stenting failure. MACEs at 30 days were similar in the 2 groups, with 19 (3.8%) in the predilatation group and 13 (2.6%) in the direct group (p = NS). Resource utilization favored the direct strategy, with decreases in balloon use, contrast media, and procedure time, but a larger number of guiding catheters was used. The 180-day MACE rate of 9.8% in the direct group was not significantly less than the rate of 10.8% in the predilatation group (p = NS). Quantitative angiographic follow-up at 6 months demonstrated in-stent binary restenotic rates of 11.4% in the predilatation group (late loss 0.88 +/- 0.53 mm) and 12.3% in the direct group (late loss 0.82 +/- 0.51 mm, p = NS) and in-segment restenosis rates of 12.2% and 13.4%, respectively (p = NS). In conclusion, a direct stenting strategy with the Multilink Tetra stent was feasible and safe in 94% of lesions and associated with lower resource utilization compared with a predilatation approach. Direct stenting was not associated with significantly lower MACE and target lesion revascularization rates and had no effect on late angiographic follow-up, with similar late loss reflecting an identical biologic response to bare metal stent placement.     

Direct coronary stent implantation does not reduce the incidence of in-stent restenosis or major adverse cardiac events: six month results of a randomized trial.

STUDY OBJECTIVE: To compare the long-term angiographic, clinical and economic outcome of direct stenting vs stenting after balloon predilatation. PATIENT POPULATION AND METHODS: Four hundred patients with coronary stenoses in a single native vessel were randomized to direct stenting vs stenting after predilatation. A major adverse cardiac and cerebral event (MACCE) was defined as death, myocardial infarction, stent thrombosis, target restenosis, repeat target- and non-target vessel-related percutaneous coronary intervention, target lesion revascularization, coronary artery bypass surgery and stroke. RESULTS: Stents were successfully implanted in 98.3% of patients randomized to direct stenting vs 97.8% randomized to stenting preceded by predilatation. The primary success rate of direct stenting was 88.3%, vs 97.8% for stenting preceded by balloon dilatation (P=0.01). The angiographic follow-up at 6 months included 333 of the 400 patients (83%). The binary in-stent restenosis rate was 23.1% of 163 patients randomized to direct stenting vs 18.8% of 166 patients randomized to balloon predilatation (P=0.32). By 185+/-25 days, MACCE had occurred in 31 of 200 (15.5%) patients randomized to direct stenting, vs 33 of 200 (16.5%) randomized to predilatation (P=0.89). At 6 months, costs associated with the direct stenting strategy (Euros 3222/patient) were similar to those associated with predilatation (Euros 3428/patient, P=0.43). However, procedural costs were significantly lower. It is noteworthy that, on multivariate analysis, a baseline C-reactive protein level >10 mg l(-1)was a predictor of restenosis (odds ratio: 2.10, P=0.025) as well as of MACCE (odds ratio: 1.94, P=0.045). CONCLUSIONS: Compared to stenting preceded by balloon predilatation, direct stenting was associated with similar 6-month restenosis and MACCE rates. Procedural, but not overall 6-month costs, were reduced by direct stenting. An increased baseline CRP level was an independent predictor of adverse long-term outcome after coronary stent implantation.     

A和B_1型病变的冠心病患者行直接支架术及随访观察

目的　评价直接支架术在A或B1 型病变的冠心病患者治疗中的可行性和安全性。方法　 111例A或B1 型病变的冠心病患者分为直接支架植入术组 (4 7例 )和球囊预扩后支架植入术组 (常规支架组 ,6 4例 ) ,比较冠心病危险因素及一般临床资料、靶血管病灶特征、支架植入后即刻效果、并发症及中期随访结果。结果　直接支架组术前不稳定性心绞痛、近期心肌梗死明显低于常规支架术组 (4 0 %比 5 3% ,17%比 2 8% ,P <0 .0 5 ) ,直接支架组介入操作时间明显短于常规支架组 (2 1.2± 11.7)比 (31.6± 9.8)min ,P <0 .0 1,直接支架组平均扩张压明显高于常规支架组 (13.3± 2 .7)比 (9.1± 1.7)大气压 ,P <0 .0 1,靶血管分布、参照血管直径、操作成功率、支架散落、支架远端血管撕裂 ,两组差异无显著性意义。经 (5 .2± 0 .4)个月随访 ,心绞痛、再次PTCA、心肌梗死及再次心肌梗死、心功能 ,两组差异无显著性。结论　A和B1 型病变的冠心病患者 ,直接支架术可缩短介入操作时间 ,即刻效果、并发症及中期临床随访与常规支架组差异无显著性意义。     

直接冠状动脉支架置入术的临床应用及影响因素

目的 探讨选择性直接冠状动脉支架置入术应用的可行性及影响因素。方法 对237例直接支架置入术患的病变特点及临床预后了分析,并与367例预扩张后支架置入术患进行了比较。结果 对筛选的254例患尝试直接支架置入术,237例（93．4％）获成功,其中A型病变52．7％,B1型病变40．1％,17例（6．7％）直接支架置入术失败,其中血管内超声肯定的钙化病变7例,斑块纤维化4例,血管严重成角6例（血管多个弯曲＞45度）。结论 对有经验的心脏介入医生筛选的病变,并避开钙化病变,严重成角血管和长病变,可考虑行直接冠状动脉动脉支架置入术。     

Comparison of direct stenting with conventional stent implantation in acute myocardial infarction

Small studies have suggested that direct stenting without balloon predilatation in ST-segment elevation myocardial infarction may reduce microcirculatory dysfunction. To examine the clinical benefits of direct stenting in a large cohort of patients who underwent primary percutaneous coronary intervention treated with contemporary pharmacotherapy, the 1-year outcomes from the multicenter, randomized Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial were analyzed. A total of 3,602 patients with ST-segment elevation myocardial infarction who underwent primary percutaneous coronary intervention were enrolled. The present study cohort consisted of 2,528 patients in whom single lesions (excluding bypass grafts) were treated with stent implantation. At operator discretion, direct stenting was attempted in 698 patients (27.6%), and stenting was performed after predilatation in 1,830 patients (72.4%). Propensity-score matching was performed to reduce bias. Direct stenting was successful in 677 patients (97.0%). ST-segment resolution at 60 minutes after the procedure was improved in patients who underwent direct compared to conventional stenting (median 74.8% vs 68.9%, respectively, p = 0.01). At 1-year follow-up, direct compared to conventional stenting was associated with a significantly lower rate of all-cause death (1.6% vs 3.8%, p = 0.01) and stroke (0.3% vs 1.1%, p = 0.049), with nonsignificant differences in target lesion revascularization, myocardial infarction, stent thrombosis, and major bleeding. Death at 1 year remained significantly lower in the direct stenting group after multivariate adjustment (hazard ratio 0.42, 95% confidence interval 0.21 to 0.86, p = 0.02) and in a propensity score-based analysis (hazard ratio 0.92, 95% confidence interval 0.88 to 0.95, p = 0.02). In conclusion, compared to stent implantation after predilatation, direct stenting is safe and effective in appropriately selected lesions in patients with ST-segment elevation myocardial infarction who undergo primary percutaneous coronary intervention and may result in improved survival.     

Influence of frequency of stenting on acute and one-year follow-up results

BACKGROUND: There has been a continuous increase in the frequency of stenting, with recent reports suggesting performing stenting in all coronary angioplasty interventions. The aim of this retrospective investigation was to study the in-hospital and 1-year event rates of the most and the least avid stent user (both highly experienced) at our institution. METHODS: A total of 322 consecutive patients undergoing coronary angioplasty at our institution were retrospectively studied. Post-intervention CK, CK-MB and troponin T values and information of major in-hospital cardiac events were obtained from the charts. Events during a 1-year follow-up were collected. Comparisons were made between patients treated by the most generous (operator 1: 71% stenting) and the most frugal (operator 2: 49% stenting) stent user. RESULTS: The 2 groups were comparable. Post-intervention CK max (418+/- 744 versus 427+/- 1250; p = 0.33), CK-MB (105+/- 159 versus 239+/-263; p = 0.07) and troponin T (149+/-326 versus 282+/- 380; p = 0.3) values were similar in both groups. In-hospital (2% versus 1.8%; p = 1) and 1-year follow-up cardiac events (21% versus 18%; p = 0.58) between both groups were also comparable. CONCLUSIONS: Stenting is a useful tool for selected patients. However, a higher frequency of stenting does not beneficially influence in-hospital or 1-year cardiac events. These findings recommend provisional stenting rather then elective stenting.     

Direct stenting in saphenous vein grafts. Immediate and long-term results

INTRODUCTION AND OBJECTIVES: Percutaneous interventions on saphenous vein grafts are associated with a worse outcome than in native vessels, mainly because of the risk of embolization. Direct stenting may diminish aggression to the vessel. This study reports the results of direct stenting in saphenous vein grafts. PATIENTS AND METHOD: We compared 2 cohorts of consecutive patients treated with direct stenting (DS) and stenting with predilatation (PD) in saphenous vein grafts between September 1998 and March 2003. In-hospital and long-term results and predictors of mortality were analyzed. RESULTS: The DS group contained 71 patients with 83 lesions, and the PD group contained 46 patients with 54 lesions. There were no differences in age, risk factors, age of the graft, ejection fraction, stent length, need for postdilatation or number of stents per lesion, although the DS group contained more women (DS=38%, PD=17%, P=.02), and stent diameter was larger (DS=3.59 [0.59] mm, PD=3.21 [0.59] mm, P=.001) in the DS group. Creatine phosphokinase elevation was > or =2-fold in 10% (DS=7%, PD=16%, P=.1). One patient died in the hospital. Median follow-up time was 36.1 months. Survival was 94+/- 2% at 12 months, 87+/-3% at 24 months, 82+/-17% at 36 months, 67+/-8% at 48 months and 58+/-7% at 60 months. Revascularization rate was 14% for the target lesion and 20.5% for the target vessel, with no differences between groups in mortality or revascularization success rate. Predictors of mortality were ejection fraction and smoking habit. CONCLUSIONS: Survival after stenting in saphenous vein grafts is similar with direct and conventional techniques, although there was a tendency toward a lower incidence of myocardial infarction with the former. Although the in-hospital results were favorable, long-term survival was less favorable with both techniques.     

Direct stenting without predilatation: a new approach to coronary intervention

BACKGROUND: Implantation of coronary stents after predilatation is a standard approach in the treatment of most coronary lesions. Stenting without predilatation could be a possible alternative way of treating a certain subset of patients. OBJECTIVE: To identify a group of patients suitable for this optional method, to evaluate their immediate clinical and angiographic outcomes and to test the feasibility and safety of this new therapeutic concept. METHODS: Ninety selected patients with 91 lesions were treated by implantation of coronary stents without predilatation. RESULTS: The mean duration of this procedure was 12.3 +/- 9.1 min and the fluoroscopic time was 3.6 +/- 2.9 min. The stenoses before and after this procedure were 77 +/- 10 and 5 +/- 9%, respectively. Predilatation, postdilatation or implantation of an additional stent was necessary for seven patients. Primary success rate was 92% with an excellent immediate clinical and angiographic outcome. No major complications occurred during direct stenting. CONCLUSION: Direct stenting is feasible using commercially available stents and could be performed for about 20% of patients for whom coronary intervention is indicated. The proper selection of lesions is of crucial importance. Lesions eligible for direct stenting should be without visible calcifications and on vessels without proximal tortuosity. This procedure proved to be safe and successful in this series of coronary interventions.     

Direct coronary stenting: effect on coronary blood flow, immediate and late clinical results.

Direct stenting (DS) was attempted in 99 coronary lesions in 94 patients while standard stenting (SS) was attempted in 113 lesions in 103 patients matched for clinical characteristics, stenosis type, and location and stent type. The angiographic result was also evaluated according to TIMI frame count method (TFC) before and after procedure. A clinical follow-up was performed 1 year after the procedure. Before the procedure, TIMI grade 3 flow was detected in 42 cases (42.4%), grade 2 in 40 cases (40.4%), grade 1 in 5 cases (5.1%), and grade 0 in 12 cases (12.1%) in the DS group; these data were similar in SS group. After the procedure, TIMI grade flow was 3 in 90 cases (92.8%) in DS group and in 87 (77.0%) in SS group (P < 0.005); grade 2 was observed in 7 case (7.2%) in DS group and in 25 (22.1%) in SS group (P < 0.005). Major adverse cardiac events during hospitalization and at follow-up were similar in two groups. Radiation exposure time and procedure costs per lesion were significantly reduced in DS group compared to SS group (10.1 +/- 8 min vs. 13.9 +/- 4.7 min, P < 0.001; and 1901 +/- 687 Euro vs. 2352 +/- 743 Euro, P < 0.001, respectively). This study confirms that, in selected patients, direct stenting is a safe and successful procedure, allowing a significant reduction in radiation exposure time and procedural costs compared to standard stenting technique. The angiographic success is confirmed by the improvement in TFC in all cases.     

Direct coronary stent implantation: safety, feasibility, and predictors of success of the strategy of direct coronary stent implantation.

This prospective study was designed to evaluate the feasibility, safety, predictive factors of success, and 6-month follow-up of stent implantation without balloon predilatation (direct stenting) in 250 patients undergoing elective stent implantation. Balloon dilatation prior to stent implantation was a prerequisite to facilitate passage and deployment of the stent. Stent technology has changed tremendously, resulting in stents with improved properties, which may allow stent placement without prior balloon dilatation. Patients with coronary lesions suitable for elective stent implantation were included in this trial. Coronary interventions were undertaken predominantly via the transradial route using 6 Fr guiding catheters. Direct stent implantation was attempted using AVE GFX II coronary stent delivery systems. Upon failure, predilatation was undertaken before reattempting stent implantation. Patient data and ECGs were obtained from case records and from personal or telephone interviews 6 months after the procedure. Values were presented as mean +/- standard deviation. Student's t-test, two-tailed at 5% level of significance, was used to compare the difference of two means. Multivariate logistic regression analysis was performed to establish predictive factors for failure of direct stenting. Two hundred and sixty-six direct stent implantations were attempted in 250 patients. Direct stenting was successful in 226 (85%) cases. Out of 40(15%) cases where direct stenting failed, balloon predilatation facilitated stent implantation in 39. In one lesion, stent implantation was not possible despite adequate predilatation. Predictive factors for failure of direct stenting on multivariate analysis were LCx lesions (P < 0.01), complex lesions (P < 0.01), and longer stents (P < 0.001). Minimal luminal diameter and percentage diameter stenosis of lesions in the successful and the failure group were not significantly different (0.94 +/- 0.39 mm vs. 0.84 +/- 0.41 mm, P = NS, and 70.2 +/- 11.2 vs. 73.2 +/- 11.2, P = NS). Stent loss occurred in five (2.0%) cases, with successful retrieval in four. One stent was lost permanently in a small branch of the radial artery. Post-percutaneous coronary intervention (post-PCI) myocardial infarction occurred in four (1.6%) patients. There were no other in-hospital events. Six-month-follow up information was obtained in 99% of patients. Subacute stent thrombosis was noted in four (1.6%) cases. Target vessel-related myocardial infarction rate was 3.2%, of which half was caused by subacute stent thrombosis. The overall reintervention rate (coronary artery bypass grafting or PCI) was 9.7%. Target lesion revascularization by PCI occurred in only 4.0%. At 6 months, overall mortality was 2.0%, of which 1.2% was due to coronary events. Direct stent implantation is safe and feasible in the majority of cases with low rate of complications. Unfavorable factors include circumflex lesion, more complex lesion morphology, and increasing length of stent. Severity of stenosis does not appear to be of predictive value. Long-term outcome is favorable with a low target lesion revascularization rate.     

Comparison of direct coronary stenting with and without balloon predilatation in patients with stable angina pectoris. BET (Benefit Evaluation of Direct Coronary Stenting) Study Group

The purpose of this study was to compare the effects of stent placement with and without balloon predilatation on duration of the procedure, reduction of procedure-related costs, and clinical outcomes. Although preliminary trials of direct coronary stenting have demonstrated promising results, the lack of randomized studies with long-term follow-up has limited the critical evaluation of the role of direct stenting in the treatment of obstructive coronary artery disease. Between January and September 1999, 338 patients were randomly assigned to either direct stent implantation (DS+; 173 patients) or standard stent implantation with balloon predilatation (DS-; 165 patients). Baseline clinical and angiographic characteristics were similar in the 2 groups. Procedural success was achieved in 98.3% of patients assigned to DS+ and 97.5% of patients assigned to DS- (p = NS), with a crossover rate of 13.9%. Compared with DS-, DS+ conferred a dramatic reduction in procedure-related cost ($956.4 +/- $352.2 vs $1,164.6 +/- $383.9, p <0.0001) and duration of the procedure (424.2 +/- 412.1 vs 634.5 +/- 390.1 seconds, p < 0.0001). At 6-month follow-up, the incidence of major adverse cardiac events including death, angina pectoris, myocardial infarction, congestive heart failure, repeat angioplasty, or coronary artery bypass graft surgery was 5.3% in DS+ and 11.4% in DS- (p = NS). Multivariate analysis demonstrated that major adverse cardiac events rates were related to stent length of 10 mm (relative risk [RR] 3.25, 95% confidence intervals [CI] 1.36 to 7.78; p = 0.008), stent diameter of 3 mm (RR 2.69, 95% CI 1.03 to 7.06; p = 0.043), and complex lesion type C (RR 2.83, 95% CI 1.02 to 7.85; p = 0.045). Thus, in selected patients, this prospective randomized study shows the feasibility of DS+ with reduction in procedural cost and length, and without an increase in in-hospital clinical events and major adverse cardiac events at 6-month follow-up.     

Coronary stenting without predilatation in a broad spectrum of clinical and angiographic situations

BACKGROUND: Direct coronary stenting without balloon predilatation has the potential benefits of a reduced risk of extended dissections, reduced fluoroscopy exposure, reduced procedural time, and potential cost savings. With the availability of superior stents and delivery systems, we review our experience with direct stent deployments in a large selected patient cohort. METHODS: We prospectively studied 158 consecutive cases of attempted coronary stenting without balloon predilatation over a 1-year period. RESULTS: Indications for the procedure included unstable angina (71%), stable angina (24%) and acute myocardial infarction (5%). Target vessels were the anterior descending artery (56%), right coronary artery (30%), circumflex artery (8%), and vein grafts (6%). Pre-procedural TIMI flows were grade 3 (91.7%), grade 2 (5.8%), grade 1 (1.3%) and 0 (1.3%). Lesion types were graded A (27%), B (61%), and C (12%). Stent types included NIR Primo (80.4%), ACS Multi-Link RX Duet (10.1%), NIR (5.1%), and others (4.4%). Stents ranged from 3.0Eth 4.0 mm in diameter (median = 3 mm) and 8Eth 32 mm in length (median = 16 mm). Stents were successfully deployed in 155 cases (98.1%); 2 (1.3%) required predilatation and 1 (0.6%) deployed stent could not be expanded and was opened by rotablation. All except the rotablator case achieved final TIMI grade 3 flow, and 66% did not require further balloon dilatation. There were no deaths or cases of urgent bypass surgery. Case duration and radiation exposure in direct stenting (32.8 +/- 18.9 minutes and 6.7 +/- 6.2 minutes, respectively) compared favorably to those in a matched group of patients in conventional stenting (47 +/- 18 minutes and 11 +/- 7 minutes) and coronary angioplasty (40 +/- 12 minutes and 10 +/- 6 minutes) for single-lesion cases (p < 0.005). Creatine kinase elevation related to the procedure was observed in 5 patients. Subacute stent thrombosis occurred in 2 (1.3%) cases. CONCLUSION: Direct coronary stenting was successfully and safely accomplished in a variety of clinical situations in selected patients.     

Treatment of focal in-stent restenosis with balloon angioplasty alone versus stenting: Short- and long-term results

BACKGROUND: Although both percutaneous transluminal coronary angioplasty (PTCA) and additional stenting can be used for the treatment for focal in-stent restenosis (ISR), no large-scale comparative data on the clinical outcomes after these interventional procedures have been reported. METHODS: In the current study we compared the in-hospital and long-term clinical results of PTCA alone (n = 266 patients, n = 364 lesions) versus stenting (n = 135 patients, n = 161 lesions) for the treatment of focal ISR, defined as a lesion length less than or equal to 10 mm. RESULTS: There were significantly more diabetic patients in the PTCA group than in the stent group (36% vs 26%, P =.04), but other baseline characteristics were similar. Lesion length and preprocedure minimal lumen diameter (MLD) were also similar in the two groups, but the stent group had a larger reference vessel diameter (3.40 +/- 0.73 mm vs 2.99 +/- 0.68 mm, P <.001). Stenting achieved a larger postprocedure MLD than PTCA did (2.95 +/- 0.95 mm vs 2.23 +/- 0.60 mm, P <.001) and a smaller residual diameter stenosis (11% +/- 15% vs 23% +/- 16%, P =.04). Angiographic success was achieved in all cases. The rate of death/Q-wave infarction of urgent revascularization was higher with PTCA than with stent (5.6% vs 0.7%, P =.02). Postprocedure creatine kinase myocardial band enzyme elevation >5 times normal was more frequent with stent (18.5% vs 9.7%, P =.05). At 1 year the two interventional strategies had similar cumulative mortality (4.6% PTCA vs 5.1% stent, P not significant) and target lesion revascularization rate (24.6% PTCA vs 26.5% stent, P not significant). By multivariate analysis, the sole predictor of target lesion revascularization was diabetes (odds ratio 2.4, 95% confidence intervals 1.2-4.7, P =.01). CONCLUSION: Repeat stenting for the treatment of focal ISR had a higher postprocedure creatine kinase myocardial band elevation rate and similar long-term clinical results compared with PTCA alone.