Recurrent very late stent thrombosis after bare-metal stent implantation.

Very late bare-metal stent thrombosis occurring beyond 1 year after stenting is uncommon. Although much attention has been paid for late stent thrombosis, long-term outcome of patients who developed late stent thrombosis is not clear. We report a case of recurrent very late stent thrombosis after bare-metal stent implantation.     

Recurrence of late-acquired incomplete stent apposition following sirolimus-eluting stent implantation

Stent thrombosis has been recognized as a potentially critical complication in percutaneous coronary intervention. In the bare-metal stent era, stent thrombosis was considered to be an acute or subacute event, occurring within 1 month after stent implantation. Recently, late or very late stent thrombosis after drug-eluting stent implantation has been brought into focus; however, the mechanism underlying this potentially fatal event is largely unknown. We report a case of critical late thrombosis 2 years after sirolimus-eluting stent implantation. Detailed serial intravascular ultrasound analyses revealed that late-acquired incomplete stent apposition, accompanied by extensive positive vascular remodeling, was involved in the pathogenesis of the nearly fatal event described in this case.     

Late stent thrombosis after implantation of a sirolimus-eluting stent.

Late stent thrombosis in the era of routine high-pressure stent deployment and combined antiplatelet therapy with thienopyridines and aspirin has become a rare but feared complication. We describe a patient with acute myocardial infarction due to late stent thrombosis 6 weeks after deployment of a sirolimus-eluting stent and 2 weeks after the discontinuation of clopidogrel. This is the first report of late thrombosis of a sirolimus-eluting stent.     

Very late stent thrombosis in late stent malapposition after sirolimus-eluting stent implantation

Late stent malapposition (LSM) has been demonstrated to be more common after drug-eluting stent (DES) implantation than after bare-metal stent (BMS) implantation. To date, this unusual intravascular ultrasonic finding after DES implantation, however, has not received enough attention, because previous studies suggested few adverse clinical sequelae from LSM. We present a case of angiographically-confirmed very late stent thrombosis (ST) in LSM after elective implantation of sirolimus-eluting stents. In this 32-year-old male patient, very late ST occurred at 29 months after DES implantation and at 20 months after the identification of LSM. Although this patient had received sufficient dual antiplatelet therapy with aspirin and clopidogrel for more than 1 year, he suffered from ST shortly after the discontinuation of clopidogrel. Thus, patients with LSM may pose a significant risk for very late ST after discontinuation of dual antiplatelet therapy. The findings suggest that dual antiplatelet therapy should be further prolonged in patients with LSM.     

Very late stent fracture associated with a sirolimus-eluting stent

Late stent thrombosis (>1 year after implantation) is a recognised complication involving drug-eluting stents. Stent fracture is increasingly being reported as a complication of drug-eluting stent, and in particular sirolimus-eluting stent use. We report the case of very late sirolimus-eluting stent fracture resulting in an acute coronary syndrome. This case report highlights the need for greater awareness and post-marketing surveillance to detect a potential mechanism for late stent thrombosis in the drug-eluting stent era.     

Late stent thrombosis associated with coronary aneurysm formation after sirolimus-eluting stent implantation

Stent thrombosis is a rare but potentially fatal complication of coronary stent implantation. Its occurrence late after drug-eluting stent (DES) deployment has led to concerns regarding their long-term safety. We report a case of late stent thrombosis 26 months after sirolimus-eluting stent (SES) (Cypher, Cordis Corp., Miami, Florida) implantation. This was associated with marked positive vessel remodeling and coronary aneurysm formation involving the stented segment of the coronary artery. The patient was on dual antiplatelet therapy at the time.     

Two cases of very late stent thrombosis after implantation of a sirolimus-eluting stent presenting as AMI

Stent thrombosis after sirolimus-eluting stent (SES) implantation has been reported to occur at 6 hours to 26 months after the procedure and usually within 2 weeks after discontinuation of antiplatelet medication. However, there are very few reports of stent thrombosis after 2 years. We report 2 cases of very late stent thrombosis after implantation of a sirolimus-eluting stent presenting as acute myocardial infarction (AMI). These late thromboses occurred about 2 years after SES implantation and over 1.5 years after discontinuation of ticlopidine.     

Late stent thrombosis in patients receiving ticlopidine and aspirin after sirolimus-eluting stent implantation.

BACKGROUND: There is little information about the efficacy of ticlopidine plus aspirin after sirolimus-eluting stent (SES) implantation. METHODS AND RESULTS: The incidence of stent thrombosis was evaluated in 1,029 patients receiving ticlopidine and aspirin after SES deployment. Clinical follow-up was obtained in 98.9% (mean follow-up 17.0+/-7.9 months). Early stent thrombosis was observed in 5 patients (0.49%). There was 1 case each of late (0.1%) and very late stent thrombosis (0.1%). CONCLUSION: Late and very late stent thrombosis in Japanese patients receiving ticlopidine and aspirin after SES deployment occurs infrequently.     

Late coronary stent thrombosis: early vs. late stent thrombosis in the stent era.

The incidence of coronary stent thrombosis is < 1%-2% in recent studies, with the highest-risk period considered to be the first 30 days following stent implantation. Recently, stent thrombosis after 30 days has been reported in patients undergoing brachytherapy with stenting. We reviewed the incidence of stent thrombosis causing myocardial infarction in nonbrachytherapy patients at our institution between 1 January 1996 and 30 November 1999. A case control methodology was employed with a 1:3 ratio of stent thrombosis to control patients. Of 1,191 patients undergoing coronary stenting, acute (< 24 hr) plus subacute (1-30 days) stent thrombosis occurred in 0.92% (11 of 1,191 patients). A further 0.76% (9 of 1,191 patients) developed late stent thrombosis after 30 days. There were no clinical or angiographic features at the time of the initial procedure that were associated with stent thrombosis as an entire group compared with control group, but early (acute and subacute) stent thrombosis patients had a smaller final stent minimal lumen diameter and longer stent length compared with patients who had late stent thrombosis or controls. Late stent thrombosis occurs in nonbrachytherapy patients and is almost as frequent as early stent thrombosis. Further studies are required to determine whether longer-term poststent pharmacological treatment may decrease or prevent this complication.     

Late stent thrombosis thirteen months after drug-eluting stent implantation

We present a case of a very late stent thrombosis which occurred 13 months after drug-eluting stent (DES) implantation. The DES was off-label used in a high-risk patient and was followed by 12-month clopidogrel administration. One month after the drug discontinuation the stent thrombosis occurred, resulting in acute myocardial infarction. The patient was successfully treated with balloon coronary angioplasty and was advised to use clopidogrel indefinitely.     

Coexistent in-stent restenosis, late incomplete stent apposition and mural thrombus in a zotarolimus-eluting stent

Drug-eluting stents (DES) have been demonstrated to dramatically reduce the rate of in-stent restenosis (ISR). However, some studies found an increased rate of late incomplete stent apposition (ISA) and late stent thrombosis (ST) in DES compared to traditional bare-metal stents (BMS). Endeavor stent, a new cobalt-alloy DES coated with phosphorylcholine and zotarolimus, has been reported to have a very favorable safety profile with few documented late-acquired ISA and late ST. In the present report, we described an interesting case with coexistent ISR, late ISA and mural thrombus in an Endeavor zotarolimus-eluting stent 8 months after primary percutaneous coronary intervention.     

The conundrum of late and very late stent thrombosis following drug-eluting stent implantation

PURPOSE OF REVIEW: Drug-eluting stents reduce restenosis compared with bare metal stents, but there is growing concern that drug-eluting stents may lead to higher rates of late stent thrombosis, a rare and potentially catastrophic complication following stenting. RECENT FINDINGS: While the data on the risk of late stent thrombosis are not definitive, several general conclusions may be drawn from the available data. Late thrombosis, while associated with high mortality and morbidity, is an uncommon complication of both drug-eluting stents and bare metal stents. Randomized trials of approved drug-eluting stents versus bare metal stents have shown additional cases of late stent thrombosis in drug-eluting stents, but no significant difference in the cumulative incidence of stent thrombosis, myocardial infarction, or cardiac death at 4 years of follow-up. Observational studies suggest higher very late stent thrombosis incidence, but the relative risks of drug-eluting stents versus bare metal stents in specific high-risk groups require further study. Although the etiology of late stent thrombosis is multifactorial, premature discontinuation of clopidogrel appears to be the most important risk factor. SUMMARY: Long-term follow-up of patients after coronary stenting has identified stent thrombosis as a rare but serious event. Ongoing clinical trials in broader patient populations will be helpful to understand the risk of late stent thrombosis with greater certainty.     

Incidence and mechanism of late stent malapposition after phosphorus-32 radioactive stent implantation

Late stent malapposition is a potential complication of intracoronary brachytherapy. The aim of our study was to determine the incidence and mechanism of late stent malapposition after implantation of phosphorus-32 radioactive stents. We analyzed 159 patients for de novo lesions after the implantation of phosphorus-32 radioactive stents. There were 15 late stent malappositions. The incidence of malapposition was higher in patients who received Hot-Ends Isostents. External elastic membrane expansion greater than plaque increase in malapposed segments was observed. Late stent malapposition is caused by a localized increase in external elastic membrane that is greater than the increase in plaque area; this is believed to be a dose-dependent phenomenon because it was more common with Hot-Ends Isostents.     

药物洗脱支架术后极晚期血栓形成原因及防治进展

药物洗脱支架能有效减少支架再狭窄率和靶血管的再次血运重建,但与金属裸支架相比,药物洗脱支架极晚期血栓（VLST）发生率呈上升趋势。研究显示药物洗脱支架术后再内皮化延迟、抗血小板药物抵抗、PCI操作技术与晚期血栓形成有密切相关。本文就 VLST形成原因、危险因素及防治策略作以下综述。     

Late peripheral stent thrombosis due to stent fracture, vigorous exercise and hyporesponsiveness to clopidogrel

Late peripheral arterial stent thrombosis usually occurs due to haemodynamically relevant in-stent restenosis. However, late stent thrombosis may be multicausal. We report here the well-documented case of a 69-year-old man with acute thrombosis of the stented superficial femoral artery after a long-distance bicycle tour. Catheter-directed thrombolysis revealed a residual stenosis located at a stent fracture site. In addition, platelet function tests revealed an inadequate platelet response to clopidogrel. In conclusion, stent fracture, strenuous exercise and hyporesponsiveness to clopidogrel may have contributed to the development of late peripheral stent thrombosis.     

Very late stent thrombosis after sirolimus-eluting stent implantation observed using optical coherence tomography and coronary angioscopy

Sirolimus-eluting stents (SES) are now commonly used for percutaneous coronary intervention (PCI) because they dramatically reduce the rates of restenosis and target lesion revascularization, even in small vessels and long lesions as compared with bare-metal stent. The unresolved issue about SES use is the possibility of late stent thrombosis. Late stent thrombosis is a very rare, but serious complication that may result in acute myocardial infarction or sudden cardiac death. However, the mechanism of late stent thrombosis with SES has not been established. We report a patient with very late stent thrombosis 37 months after SES implantation who underwent optical coherence tomography and coronary angioscopy.     

Acute ST-elevation myocardial infarction 6 years following a sirolimus-eluting stent secondary to complete stent fracture

With increasing coronary interventions, coronary stent fracture following implantation of drug-eluting stents is being commonly recognized. Though isolated strut fractures are often only incidental findings, more severe forms of stent fracture with complete transection have adverse clinical outcomes. Most such cases are reported within several months following the index angioplasty. We report an unusual presentation of late stent fracture following a sirolimus-eluting stent, presenting with acute myocardial infarction 6 years after the initial stent implantation. The various mechanisms underlying fracture of drug-eluting stents are reviewed. Because no known mechanisms were noted in our case, unknown factors may also play a role in the genesis of stent fracture. Clinicians need to be aware that such complications may present rarely, extremely late after the index procedure as an acute myocardial infarction.     

Very late stent thrombosis associated with multiple stent fractures and peri-stent aneurysm formation after sirolimus-eluting stent implantation.

Previous randomized trials have shown that drug-eluting stents (DES) are superior to bare-metal stents in reducing the need for target lesion revascularization, but safety issues with DES have recently been raised. We report a rare case of very late stent thrombosis 35 months after sirolimus-eluting stent implantation associated with delayed 5-segment stent fractures and peri-stent aneurysm formation.     

Thrombosis and acute myocardial infarction as consequences of very late stent malapposition after implantation of a drug-eluting stent

The use of drug-eluting stents (DES) provides early and late benefits demonstrated by angiographic and clinical outcomes. Here we report a case of late stent thrombosis and acute myocardial infarction caused by late stent malapposition (LSM) of a DES at 16 months after the procedure. We successfully treated the patient with balloon angioplasty after intravenous thrombolytic therapy. This case illustrates that a LSM can develop at any time after DES implantation and can result in acute coronary syndrome. Therefore, clinicians should be aware of the possibility of late cardiac events after implantation of DES.     

Disruption of atherosclerotic neointima as a cause of very late stent thrombosis after bare metal stent implantation

A male who were implanted bare metal stent 11 years ago were admitted for acute coronay syndrome. Optical coherence tomography showed a neointimal disruption and integrated backscatter intravascular ultrasound revealed a lipid pool around the disrupted neointima, suggesting newly formed atherosclerotic neointima developed after bare metal stent implantation. The disruption of atherosclerotic neointima may represent a new potential mechanism of very late stent thrombosis after bare metal stent implantation.