Intravascular ultrasound catheter entrapment after coronary artery stenting.

Intracoronary ultrasound (IVUS) facilitates optimal stent deployment in the treatment of coronary artery disease, which may favorably improve long-term outcome after stenting. Complications associated with IVUS include coronary vasospasm and rarely more serious adverse events such as vessel perforation or stent deformation. We report an IVUS catheter tip entrapment within a self-deploying nitinol stent.     

Bent stents: A method to facilitate delivery of the Palmaz-Schatz stent in tortuous and rigid coronary arteries

The Palmaz-Schatz stent delivery system (PS 153) and “bare” PS 204 stents are relatively high-profile, rigid devices that can be difficult to deliver to lesions beyond tortuous, irregular, or rigid proximal segments. Described herein is a method of mounting and shaping a Palmaz-Schatz stent on a low-profile balloon that provides a steerable, low-profile, and secure stent delivery system. Also described is the successful use of this method in four consecutive cases where Palmaz-Schatz stents could not be delivered to the lesion site due to severely angulated, irregular, or rigid proximal vessel segments. Cathet. Cardiovasc. Diagn. 44:341–344, 1998. © 1998 Wiley-Liss, Inc.     

Intracoronary stent implantation via the brachial approach: A technique to reduce vascular bleeding complications

To reduce the incidence of vascular complications of intracoronary stent implantation, we used the brachial approach. We attempted implantation of the Palmaz-Schatz stent via the brachial artery approach at 10 lesions in 9 patients. Stent delivery was successful at 8 lesions. Balloon angioplasty was successfully performed in the 2 failed cases, 1 of whom required surgical repair of the brachial artery. Intravenous anticoagulation was uninterrupted from the time of stent placement until therapeutic prothrombin times from oral warfarin therapy were obtained. Neither acute nor long-term major bleeding occurred in the 9 patients. There were no embolic events, myocardial infarctions, or deaths. One subacute thrombosis occurred, and the patient underwent bypass surgery. To evaluate the risks and benefits of the brachial approach, we compared these 9 patients with 41 who had stent placement by the femoral approach during the same period. Lesion characteristics were similar in these 2 groups. There were no significant differences in the success rate or angiographic outcome between the 2 groups. Seven (17%) patients in the femoral group had vascular access complications requiring surgery, compared with 1 (11%) in the brachial group. No patient in the brachial group required transfusion, compared with all 7 of the patients who had femoral vascular complications. The potential reduction in bleeding complications makes the brachial approach to stent implantation attractive in selected patients.     

Immediate results and dilatation effect of the vein-covered Palmaz-Schatz stent assessed by intravascular ultrasound

To evaluate the clinical results of stenting using the vein-covered Palmaz-Schatz (PS) stent by intravascular ultrasound (IVUS). Twenty-eight patients with angina pectoris or confirmed ischemia were entered into this study. Thirteen were allocated to the vein-covered PS stent group and 15 to the normal Palmaz-Schatz stent group. The immediate clinical results in these groups and changes in lumen dimension as assessed by IVUS, were investigated. Acute success was 100% in both groups. There were no immediate complications. Subacute thrombosis occurred in one patient in the vein-covered PS group. In the vein-covered PS group, percent diameter stenosis of the involved coronary artery changed from 70.2% before stenting to 8.8% immediately after and 42.2% at 5 months follow-up. The respective values were 84.5%, 13.4%, and 36.5% in the normal Palmaz-Schatz group. Restenosis in the vein-covered group was 23.1% and in the Palmaz-Schatz group was 20%, showing no significant differences between the two groups. The luminal area in the vein-covered group as assessed by IVUS increased from 3.2 mm² to 7.4 mm² (pre to post) and from 3.2 mm² to 8.2 mm² in the normal Palmaz-Schatz group. The plaque area decreased from 13.6 mm² to 10 mm² (pre to post) in the vein-covered group and from 13.0 mm² to 9.2 mm² in the Palmaz-Schatz group. In this study, conducted in a limited number of cases, it is possible to use vein-covered stent like as usual Palmaz-Schatz stent. The vein-covered stent had less dilative effect compared with the Palmaz-Schatz stent. This was probably because of its increased profile but there was no difference in the occurrence of subacute thrombosis or in restenosis rate. Cathet. Cardiovasc. Diagn. 44:276–282, 1998. © 1998 Wiley-Liss, Inc.     

Transluminal extraction atherectomy and adjunctive balloon angioplasty for restenosis after palmaz-schatz coronary stent implantation

Two patients who developed restenosis after implantation of Palmaz-Schatz coronary stents were successfully treated by transluminal extraction atherectomy and there has been no recurrence on follow-up angiograms. The optimum strategy for managing restenosis after coronary stenting remains unclear, but transluminal extraction atherectomy appears to be a safe and effective option. © 1993 Wiiey-Liss, Inc.     

Coronary aneurysm after bailout stent implantation: Diagnosis of a false lumen with intravascular ultrasound

This case report describes the intravascular ultrasound (IVUS) evaluation of a coronary artery aneurysm, developed in a stented segment within 6 mo after bailout stenting. Analysis of the IVUS images provides in vivo insights in the vessel-remodeling process after mechanical injury. The proximal entrance of the false lumen could be clearly visualized as well as the relationship between the stent struts, neolumen, and vessel wall. The discussion is focused on the options for management of such patients. Cathet. Cardiovasc. Diagn. 41:407–410, 1997. © 1997 Wiley-Liss, Inc.     

Coronary plaque morphology affects stent deployment: Assessment by intracoronary ultrasound

The purpose of this study was to evaluate the changes in arterial wall morphology induced by coronary stent implantation and the influence of plaque morphology on stent expansion by intravascular ultrasound. Intravascular ultrasound imaging was performed in 25 lesions before and after Palmaz-Schatz stent implantation. In the 25 lesions with ultrasound images before and after stent deployment angiographic percent diameter stenosis decreased from 71% ± 11% to 6% ± 14%. By ultrasound there was a gain in luminal area from 2.0 mm² ± 1.5 mm² to 6.6 mm² ± 2.1 mm² owing to a gain in external elastic membrane area of 2.5 mm² ± 1.7 mm² and reduction of plaque area of 2.1 mm² ± 1.7 mm². Calcified lesions (n = 8) showed significantly less relative luminal gain (218% ± 128% vs. 421% ± 276%, P = .01), and stent expansion was significantly less symmetric (minimal/maximal stent diameter 0.8 ± 0.1 vs. 0.9 ± 0.1, P = .002) as compared to non-calcified lesions (n = 17). The difference in lumen area within the stent between the previously stenotic area and the ends of the stent was significantly larger in calcified lesions as compared to non-calcified lesions (29 ± 28% vs. 8 ± 23%, P = .03). Both vessel stretch and plaque reduction contribute to the luminal gain after coronary stenting. Calcified lesions interfere with optimal stent expansion. © 1996 Wiley-Liss, Inc.     

Use of bare-mounted Palmaz-Schatz stents employing the stent saddle technique on the delivery balloon: A single center experience

The major limitations of the Palmaz-Schatz stent stem from the design of its stent delivery system (SDS). The SDS is bulky and has poor trackability in lesions with proximal tortuosity and/or vessel calcification. The use of bare-mounted Palmaz-Schatz stents on low profile balloons represents an alternate approach for lesions that are not accessible for stenting with the SDS. Thus we evaluated the indications, procedural success rate, and in-hospital complications of patients undergoing bare stenting at a single center between 1 October 1995 through 30 September 1996. A total of 363 coronary interventions were performed during this period, including coronary stenting in 194 vessels. In 18 of these 194 vessels, bare-mounted Palmaz-Schatz stents were used. The indications for bare stenting were: inability to deliver the Palmaz-Schatz stent on SDS for suboptimal angioplasty results or acute/threatened abrupt closure; use of half stents; stenting in vessels < 3.0 mm; intermediate disease in the proximal segment that would have precluded optimal visualization of stent placement; and use of guides 7 French or smaller. Bare stenting was successful in 15 of the 18 patients (vessels) in whom it was attempted. There were no deaths, myocardial infarctions, stent thrombosis, repeat interventions, or significant bleeding in patients with successful bare stent delivery. The stents were successfully retrieved in the three patients in whom the stent could not be advanced into the target coronary segment. One of these patients had a propagated spiral dissection prior to attempts at bare stenting and required emergent bypass surgery. The remaining two patients with failed deployment had suboptimal angioplasty results but had an uncomplicated hospital course. Thus bare stenting represents an alternate percutaneous approach to tackle suboptimal procedural results and/or complications in patients who have failed stent deployment with the standard sheathed stent delivery system currently available in the United States. Cathet. Cardiovasc. Diagn. 41:361–368, 1997. Published 1997 Wiley-Liss Inc.

1 This article is a US government work and, as such, is in the public domain in the United States of America.

     

Facilitated advancement of the Palmaz-Schatz stent delivery system with the use of an adjacent 0.018′ stiff wire

The 5.0 French Palmaz-Schatz stent delivery system is a relatively bulky, stiff system which can be advanced only over a 0.014′ wire. Although crossing failure is rare, advancement of the delivery system through tortuous, rigid vessels may be unsuccessful. We report on four consecutive cases in which the initial advancement of the Palmaz-Schatz stent delivery system was unsuccessful due to vessel tortuosity or vessel angulation. The use of a 0.018′ stiff wirer adjacent to the Palmaz-Schatz delivery system, to “straighten” the vessels and to give additional guide catheter support, allowed for the successful advancement and delivery of coronary stents in all four cases. © 1996 Wiley-Liss, Inc.     

Effect of stent design on reduction of elastic recoil: A comparison via quantitative intravascular ultrasound

The increase in minimum lumen diameter achieved by coronary stent placement can be further enhanced by reducing the immediate recoil that occurs after stent deployment. The effect of various stent designs—flexible coils, slotted tubes, and a locking stent—on minimization of postdilation stent recoil was evaluated using an in vitro model of circumferential compression. The stents were expanded to 7 atm (3.82 ± 0.02 mm); as pressure was reduced, lumen diameter and cross-sectional area (CSA) were determined by on-line intravascular ultrasound imaging (30 MHz) positioned inside the dilating balloon (n = 10–15 inflation-deflation cycles). Stent recoil was assessed by calculation of percent change in CSA from 7 atm to negative balloon pressure: −33.1 ± 5.6%(GR-II) and −22.4 ± 3.8%(Wiktor) in the coil stents; −20.0 ± 4.2%(JJIS coronary), −8.4 ± 2.6%(JJIS biliary), and −6.9 ± 1.5%(Multilink) in the slotted tube stents; and −1.9 ± 3.2%in the Navius ZR1 locking stent (P<0.05 vs. Multilink, P<0.0001 vs. others). A range of resistances to recoil is demonstrated by this model, with coil stent designs undergoing greater elastic recoil than slotted tube stent designs. The locking stent design demonstrated the greatest radial strength and the most reduction in elastic recoil. Cathet. Cardiovasc. Intervent. 47:251–257, 1999. Published 1999 Wiley-Liss, Inc.     

Extensive intramural hematoma as the cause of failed coronary angioplasty: Diagnosis by intravascular ultrasound and treatment by stent implantation

Dissections after coronary angioplasty are the major cause of ischemic events following percutaneous transluminal coronary angioplasty (PTCA) and may require additional measures such as intravascular stent deployment to relieve or prevent acute vessel closure. We describe a rare type of dissection after PTCA which caused a severe obstruction of the vessel segment proximal to the dilatation site without a visible dissection flap. Intravascular ultrasound was used to elucidate the morphology of the proximal vessel obstruction, which revealed an intramural hematoma extending into the proximal vessel segment as underlying mechanism. A Palmaz-Schatz stent was placed at the entry site of this hematoma, which led to the relief of the proximal vessel obstruction. After 3 months of anticoagulation therapy the repeat coronary angiography showed no significant restenosis. This demonstrates the unique insight into the underlying morphology of failed PTCA by intravascular ultrasound, which can help to manage even rare and unusual complications. © 1995 Wiley-Liss, Inc.     

经桡动脉植入Firebird药物支架86例临床观察

目的 观察经桡动脉途径植入Firebird药物支架在冠状动脉性心脏病(冠心病)介入治疗中的安全性和有效性.方法 回顾性分析86例经桡动脉途径植入国产药物洗脱支架冠心病患者的临床资料,观察术中并发症发生率、术后随访主要心血管不良事件发生率和血管再狭窄率.结果 共植入国产药物洗脱支架113枚.86例患者住院期间无血栓形成和临床随访无主要心血管事件发生,术后6个月冠状动脉造影复查无支架内再狭窄.结论 经桡动脉途径在冠心病介入治疗中安全有效,国产药物支架近期能够有效预防冠状动脉介入治疗后血管再狭窄.     

Short-term angiographic and long-term clinical follow-up of a patient with a malexpanded vein graft stent

Optimal stent expansion is considered imperative today in order to prevent subacute stent thrombosis and allows us to minimize antithrombotic therapy. The short-term angiographic and long-term clinical follow-up of a patient with a suboptimally expanded vein graft balloon expandable stent is presented. Intensive antithrombotic treatment along with unimpeded blood flow were probably highly beneficial. Cathet. Cardiovasc. Diagn. 41:413–414, 1997. © 1997 Wiley-Liss, Inc.     

Early clinical experience with the multi-link coronary stent

The Multi-Link coronary stent (Advanced Cardiovascular Systems, Santa Clara, CA) is a balloon expandable stent carved from a stainless steel cylinder and is composed of 12 corrugated rings connected by multiple links. This design gives the stent great flexibility and conformity as well as radial strength. For the 3 month period from November 1995 to January 1996, all patients undergoing stent implantation in our institution were treated with this device, except for vessels smaller than 2.7 mm or larger than 3.7 mm in diameter, left main disease, or those who could not tolerate anticoagulation therapy. Forty patients, with a total of 42 arteries or 44 lesions, were treated with 56 stents, or 1.33 stents per artery. Clinical presentation included stable angina in 13 (32.5%), unstable angina in 24 (60%), acute myocardial infarction in 2 (5%), of whom 1 was in cardiogenic shock, and atypical symptoms with an abnormal thallium stress test in 1 (2.5%). According to the American College of Cardiology/American Heart Association (ACC/AHA) classification, 8 lesions (18%) were type A, 14 (32%) type B1, 11 (25%) type B2, and 11 (25%) type C. Forty-three lesions (97.7%) were de novo and 1 (2.3%) restenotic. Stent delivery was successful in all patients. Complications included 1 balloon rupture at 7 atm but without sequelae, and 2 patients in whom the coronary guide wire became kinked and locked inside the catheter shaft of the stent delivery system but stent delivery was eventually successful. Mean diameter stenosis was reduced from 76 ± 13% prestenting to 2 ± 9% poststenting and minimal lumen diameter increased from 0.87 ± 0.38 to 2.82 ± 0.34 mm. There were no acute-subacute stent thromboses, bleeding/vascular complications, or major cardiac events such as myocardial infarction, coronary artery bypass surgery, or death during a follow-up period of 2–5 months (mean 3.6 months). In conclusion, our early clinical experience with the Multi-Link stent is very encouraging, with a very high rate of successful delivery and minimal complications. © 1996 Wiley-Liss, Inc.     

Comparison of sirolimus‐eluting stent,paclitaxel‐eluting stent,and bare metal stent in the treatment of long coronary lesions

Objective: This study compared the efficacy of the sirolimus‐eluting stent (SES), the paclitaxel‐eluting stent (PES), and the bare metal stent (BMS) for long coronary lesions. Background: The outcome of drug‐eluting stent (DES) implantation in long coronary lesions remains unclear. Methods: The study involved 527 patients with de novo long coronary lesions (≥24 mm), which were treated with long (≥28 mm) SESs (223 lesions), PESs (194 lesions), or BMSs (201 lesions). Results: Lesions in the SES (36.0 ± 14.9 mm, P < 0.001) and PES (36.3 ± 14.5 mm, P < 0.001) groups were longer than those in the BMS group (32.0 ± 12.3 mm), meaning the two DES groups had longer stented segments than did the BMS group. Six‐month angiographic follow‐up showed the SES (9.3%, P < 0.001) and PES (21.3%, P < 0.001) groups had lower in‐segment restenosis rates than that of the BMS group (42.5%). The rate of major adverse cardiac events (MACE) including death, myocardial infarction, and target lesion revascularization at 9 months was higher in the BMS group (26.6%) than that in the SES (13.0%, P < 0.001) and PES (15.7%, P < 0.001) groups. Posthoc analysis of the two DES groups showed that the in‐segment restenosis rate was lower for the SES than that for the PES group (P = 0.002), while the MACE rate was similar. Conclusions: The use of DESs for long coronary lesions appears to be safe and more effective than the use of BMSs in terms of restenosis and adverse clinical events. SES use was associated with lower late luminal loss and a lower angiographic restenosis rate compared with PES use. © 2006 Wiley‐Liss, Inc.     

Initial experience with the Cordis stent: Analysis of serial angiographic follow-up

To evaluate the efficacy of the more flexible Cordis stent, a prospective angiographic follow-up study was performed. Implantation of the Cordis stent was attempted in 99 consecutive patients with 103 native coronary lesions from January 1994 to July 1995. Clinical success, defined as final diameter stenosis of <50% without death, bypass surgery, or Q-wave myocardial infarction, was achieved in 88% of the patients. There were no in-hospital deaths. In-hospital subacute stent occlusion occurred in only one case. Follow-up angiograms were obtained in 86 (95%) eligible lesions. The minimal luminal diameter improved from 1.03 ± 0.31 to 2.82 ± 0.31 mm, but started to decrease at 1 mon (2.57 ± 0.24 mm), and continued to decrease throughout the 6 mon (2.00 ± 0.61 mm), the biggest reduction being between 1 and 3 mon (−0.57 ± 0.50 mm). Angiographic restenosis (stenosis ≥50%) occurred in 23% of the lesions; a revascularization procedure of the target lesion was required in 12% of the patients. Multivariate analysis identified age, diabetes mellitus, and preprocedural reference diameter to be predictors of angiographic restenosis. In conclusion, the Cordis stent can be implanted successfully with a low complication rate and a clinical outcome at least comparable to other stent studies. Cathet. Cardiovasc. Diagn. 42:166–172, 1997. © 1997 Wiley-Liss, Inc.     

经桡动脉冠状动脉腔内支架术治疗冠状动脉复杂病变

目的:比较经桡动脉与股动脉途径经皮冠状动脉介入治疗冠状动脉复杂病变时间、治疗成功率和并发症。方法:回顾性对照分析近8个月来100例冠状动脉复杂病变介入治疗经桡动脉（A组50例）,股动脉（B组50例）成功率及并发症。结果:两组患者手术成功率相似（94%vs90%,P>0.05）;经皮冠状动脉介入治疗总时间两组间差异无显著性（62±14与62±10min,P>0.05）。但A组术后并发症显著低于B组。结论:经桡动脉途径与股动脉途径介入治疗冠状动脉复杂病变成功率相似,但前者术后并发症少。