Pathological assessment of very late bare metal stent thrombosis in the left main coronary artery: a case report

Background

Late catch-up phenomenon following stent implantation is a well-known complication. However, no report has evaluated thrombosis after 9 years with multi-modality and pathological evaluation.

Case summary

A 71-year-old man with stable angina underwent elective percutaneous intervention of the left main coronary artery with implantation of a bare metal stent (BMS) 9 years ago. At the 9-year follow-up, coronary computed tomography (CCT) and coronary angiography (CAG) findings revealed a thrombus-like structure in the BMS slightly protruding into the sinus of Valsalva. Therefore, the previously prescribed double-antiplatelet therapy was replaced with an anticoagulant and clopidogrel, and a potent statin treatment was initiated. After the changes in drug treatment, follow-up examinations with CCT at 1 and 3 months suggested a decrease in the size of the thrombus; however, it appeared to increase after 6 months. Subsequently, the patient underwent surgical intervention. Pathological assessment of the explanted stent showed a proteoglycan-dominated extracellular matrix with few smooth muscle cells suggesting an organized thrombus.

Discussion

It should be emphasized that multiple factors might be responsible for very late stent thrombosis, such as peri-stent strut chronic inflammation involving proteoglycans, stent protrusion, and poorly controlled type 2 diabetes mellitus, possibly further inducing inflammatory cells.

[Analysis of short-term and long-term clinical outcomes in patients with acute myocardial infarction after one year of coronary stent implantation]

Objective: To observe in-hospital and 1-year prognosis of patients with acute myocardial infarction after one year of coronary stent implantation. Methods: From January 2015 to February 2018, 329 patients with acute myocardial infarction (AMI) after 1 year of coronary artery stent implantation were enrolled and received coronary angiography. These patients were divided into two groups (very late stent thrombosis (VLST) group and denovo group) according to whether the occurrence of acute myocardial infarction was due to stent thrombosis (ST), and in-hospital and long-term (1 year) outcomes were compared between the two groups. The primary end points included cardiac death and recurrent acute myocardial infarction. The secondary study end points included target lesion revascularization (TLR), re-stent thrombosis, heart failure, and stroke. Results: In total, 72.9% of patients with AMI after one year of coronary stent implantation were caused by VLST. There were no significant differences of both primary and secondary end-point events between the two groups during in-hospital period (3.3% vs 3.4%, P=0.987; 5.4% vs 4.5%, P=0.956). After a mean follow-up of 1 year, there were no significant differences of the primary end-point events between the two groups. The secondary end-point events and TLR incidence were higher in the VLST group (16.3% vs 6.7%, P=0.026; 9.6% vs 2.2%, P=0.026). Kaplan and Meier survival analysis showed that there were no significant differences of the 1-year cumulative non-primary and non-secondary end-point survival rates between the two groups (P=0.124 and 0.004, respectively). COX regression analysis showed that heart function ≥Ⅲ level (Killip's) and VLST were independent predictive risk factors for end-point events, while postprocedural thrombolysis in myocardial infarction (TIMI) flow grade 3 was an independent protective factor. Conclusion: In-hospital end points show no significant differences between VLST and denovo groups patients. However, the VLST group patients have a poor prognosis and a higher proportion of TLR after 1 year follow-up. The patients with heart function ≥Ⅲ level (Killip's) or VLST have a poor prognosis, while the patients with postprocedural TIMI flow grade 3 have a good prognosis.

A case report of Kounis syndrome presenting with a rash, very late stent thrombosis and coronary evaginations

BACKGROUND

Very late stent thrombosis (ST) is a concern in the era of drug-eluting stents (DESs), and ST is associated with peri-DES coronary artery aneurysmal lesions or coronary evaginations. An increasing number of cases of concurrent systemic allergic reaction and ST have been reported as Kounis syndrome (KS) in the literature. The number of patients with very late ST caused by KS is small, and further investigation of the potential pathophysiology is required.

CASE SUMMARY

We report a case of KS that manifested as systemic urticaria followed by very late ST 14 years after placement of two sirolimus-eluting stents (SESs). Three months after the event of ST, coronary evaginations at the stented segments were detected on intravascular optical coherence tomography.

DISCUSSION

Coronary evaginations are associated with local hypersensitivity, stent malapposition, uncovered strut, and flow disturbance that may predispose to ST. Systemic allergic reactions are known to promote platelet adhesion and aggregation. This case of KS suggests a pathophysiology in which the synergic effects between the coronary evaginations and a systemic allergic reaction may contribute to very late ST. For patients with Type 3 KS, performing follow-up intracoronary imaging tests may be important to confirm potential coronary evaginations, especially in patients with SESs.

Successful treatment of very late drug-eluting stent thrombosis using bare-metal stent evaluated using intravascular ultrasound and optical frequency domain imaging

A 65-year-old man who underwent percutaneous coronary intervention with sirolimus-eluting stents (SESs) 2 years ago was admitted with recurrent acute chest pain. Coronary angiography showed thrombotic occlusion within the SESs. After aspiration thrombectomy, multi-focal peri-stent contrast staining (PSS) was observed. Optical frequency domain imaging (OFDI) showed intracoronary thrombus, incomplete stent apposition (ISA), and multiple inter-strut hollows. Intravascular ultrasound (IVUS) images showed positive vessel remodeling. We deployed bare-metal stents in the SESs. Follow-up angiography showed no in-stent restenosis or PSS. OFDI showed well-covered stent surface with homogeneous neointima, without ISA. Additionally, IVUS images showed that the vessel remodeling had not worsened.

Very long-term clinical and angiographic outcomes after sirolimus- and paclitaxel-eluting stent placement for ST-elevation myocardial infarction: a propensity score-matched comparison

We conducted a retrospective examination of the very long-term outcomes of placing sirolimus (SES) and paclitaxel (PES)-eluting stents in patients with ST-elevation myocardial infarction (STEMI). This was a nonrandomized, retrospective, single-center study that included 872 first STEMI patients who underwent successful placement of either SES (n = 547) or PES from November 2004 to April 2012. The primary end point was the incidence of severe cardiac events comprising cardiac death, nonfatal recurrent myocardial infarction, and definite stent thrombosis (ST). The frequency of target lesion revascularization (TLR) was also compared. A propensity score-matched analysis was used to adjust the 29 baseline variables. In the baseline-adjusted cohorts in 231 STEMI patients in each arm, the frequency of the primary end point in the SES group (5.6 %) during the follow-up duration of 2583 ± 806 days was not significantly different from that in the PES group (6.1 %, follow-up: 1866 ± 699 days). The cumulative primary end point-free ratio in the SES group was not significantly different from that in the PES group (p = 0.503). The frequency of TLR in the SES group (7.5 %) was significantly lower than that in the PES group (16.9 %, p = 0.005), with and the significantly higher cumulative TLR-free ratio in the SES group than that in the PES group (p < 0.001). The very long-term clinical outcomes after SES or PES placement for STEMI patients were statistically equivalent. SES showed the better angiographic outcomes for STEMI compared to PES.

[Very late drug-eluting stent thrombosis by stent fracture]

The superiority of drug-eluting stents in reducing the risk of in-stent restenosis compared to bare-metal stents is no longer challenged. Nevertheless, the drug-eluting stents may carry long-term risk of late and very late stent thrombosis. The promoting factors of this complication are usually divided into three chapters depending on the patient, the procedure and the stent. Indeed, the literature has reported several parameters related to the stent itself, such as its length, the malapposition, its diameter, but also more rarely the occurrence of stent fracture. We present the case of a patient admitted for myocardial infarction after a very late thrombosis of Cypher drug-eluting stent four years after its implantation and related to stent fracture.

Efficacy of Endeavor zotarolimus-eluting stent implantation for the treatment of very late stent thrombosis with late-acquired incomplete stent apposition after sirolimus-eluting stent implantation

Very late stent thrombosis (VLST) is a serious complication after percutaneous coronary intervention. However, the best therapy for VLST with late-acquired incomplete stent apposition and incomplete neointimal coverage remains unknown. In these cases, neointimal coverage was nearly complete and no late-acquired malapposition was detected at 18 months after Endeavor zotarolimus-eluting stent (ZES) implantation for the treatment of VLST with late-acquired incomplete stent apposition after sirolimus-eluting stent implantation. We presented that Endeavor ZES implantation may become an attractive therapeutic strategy for the treatment of VLST with late-acquired incomplete stent apposition and incomplete neointimal coverage.

Very late mesenteric bare metal stent thrombosis in the setting of cessation of antiplatelet agents

We report a case of a 73 year-old man admitted for acute mesenteric ischaemia. Eight years before, he had a first mesenteric ischaemic event treated by left colectomy and angioplasty of both main coeliac artery (MCA) and superior mesenteric artery (SMA); the patient was discharged on lifelong clopidogrel and aspirin. One month before his admission for the index event, he had a major haematuria; clopidogrel was stopped first, then aspirin because of recurrent haematuria. Five days after withdrawal of both antiplatelet drugs, the patient presented with acute mesenteric ischaemia. Urgent aortography showed in-stent occlusion of SMA and in-stent restenosis of MCA; we performed ad hoc thrombus aspiration of SMA and balloon angioplasty of MCA. The patient was discharged seven days after, without complications. This case shows that very late stent thrombosis in digestive artery can occur in the setting of antiplatelet arrest and urgent endovascular intervention constitutes a seductive alternative for surgery when performed early after symptoms onset.

Very late stent thrombosis after sole stent-assisted coiling at the paraclinoid giant aneurysm : could prophylactic antiplatelet therapy be ceased at the only 1 year after procedure?

Stent thrombosis is a major limitation of stent-assisted coiling, which is an effective method for treating wide-necked aneurysms. Although early in-stent thrombosis has been reported, very late stent thrombosis (VLST) (>1 year) has not been reported following implantation of a single self-expandable stent designed for coiling. Herein, the authors present a case of VLST that occurred 14 months after single stent implantation in a large paraclinoid aneurysm with an ultra-wide neck involving the parent artery circumferentially. This case indicates the need for establishing guidelines regarding the optimal duration of prophylactic antiplatelet therapy following stent-assisted coiling, which remains undefined in the neuroendovascular field.

Simultaneous occlusion of left anterior descending and left circumflex arteries by very late stent thrombosis: vascular response to drug-eluting stents assessed by intravascular ultrasound

Very late stent thrombosis (VLST) is a catastrophic complication after implantation of a drug-eluting stent (DES). It has been reported that VLST is associated with pathological changes, which often include late acquired incomplete stent apposition (LAISA) with thrombus formation. In addition, the vascular response to the stent (evaginations, neointimal growth, and thrombosis) and the incidence of LAISA are reported to vary among the different types of DES. We experienced a patient with cardiogenic shock induced by simultaneous VLST of both the left anterior descending artery (LAD) and the left circumflex artery (LCX) at 3 years after implantation of two sirolimus-eluting stents. Intravascular ultrasound (IVUS) showed LAISA of both arteries. A paclitaxel-eluting stent, which had been implanted in the right coronary artery 3 years earlier, did not show such a finding. IVUS revealed "different vascular reactions" to "different types of DES" in this patient.

Post-operative simultaneous very late two-vessel drug eluting stent thrombosis with sparing of bare metal stent in a Jehovah's witness after clopidogrel withdrawal

Very late stent thrombosis is a feared complication after drug-eluting stent (DES) implantation. Several factors related to the patient, generation and type of the deployed stent, procedure, and premature antiplatelet withdrawal are known to contribute to this complication. Herein, we describe a case of a Jehovah's witness patient who developed simultaneous two-vessel 1st generation DES thrombosis 5.4 and 3.5 years after deployment [with sparing of the bare metal stent (BMS)] in the immediate post-operative period secondary to clopidogrel withdrawal. The case was complicated by ST-segment elevation myocardial infarction, cardiogenic shock, and a ventricular fibrillation cardiac arrest requiring urgent percutaneous coronary intervention. The acute thrombosis of DESs with sparing of the BMS exemplify how they are more prone to this complication due to delayed endothelialization of stent struts and neoinitimal coverage. <Learning objective: Extreme caution should be excercised when attempting to withdraw antiplatelets immediately before surgery in patients with drug eluting stents even if the recomended 12-month period of dual antiplatelet therapy has elapsed because of the risk of very late stent thrombosis.>.

Stent malapposition, as a potential mechanism of very late stent thrombosis after bare-metal stent implantation: a case report

A 90-year-old man was admitted to our hospital with acute ST-segment elevation myocardial infarction. He had a history of post-infarction angina pectoris 79months ago and had a bare-metal stent (BMS) implanted in the proximal left anterior descending artery at our hospital. Emergent coronary angiography demonstrated thrombotic occlusion in the previously stented segment. After catheter thrombectomy, antegrade flow was restored, but 90% stenosis with haziness persisted in the proximal and distal portions of the previously stented segment. Intravascular ultrasound imaging showed interstrut cavities or stent malapposition at the proximal and distal sites of stented segment. In close proximity to the sites, residual thrombi were also observed. Optical coherence tomography (OCT) demonstrated neither lipid-laden neointimal tissue nor rupture but clearly demonstrated residual thrombus adjacent to the malapposed region in addition to the stent malapposition. PCI with balloon was successfully performed and stent apposition was confirmed by OCT. Stent malapposition is an unusual mechanism of very late stent thrombosis after BMS implantation. OCT can clearly reveal the etiology of stent thrombosis.

A rare mechanism of very late bare metal stent thrombosis--role of optical coherence imaging in its evaluation and management

Very late stent thrombosis is an uncommon event following implantation with bare metal stents (BMS) in coronary arteries. Long term follow up studies have shown that a small number of BMS develop very late thrombosis following years of stability. Atherosclerotic transformation of neointimal tissue is increasingly being recognised as the cause of these adverse events. A 49 year-old male presented with acute inferior wall myocardial infarction resulting from thrombosis of the BMS implanted in his right coronary artery five years earlier. He was successfully thrombolysed and his coronary angiogram showed mild diffuse instent restenosis. The intravascular optical coherence tomography revealed instent neoatherosclerotic plaque rupture without any flow limiting stenosis as the likely culprit event.

Incidence and predictors of the late catch-up phenomenon after drug-eluting stent implantation

BACKGROUND

Although clinical restenosis within 1 year after percutaneous coronary intervention has been remarkably reduced with the advent of drug-eluting stents (DES), the late catch-up (LCU) phenomenon remains an issue despite medical advances. The aim of this study was to investigate the incidence and predictive factors of the LCU phenomenon in an unselected population treated with first-generation DES.

METHODS

A total of 923 patients treated with DES between June 2004 and August 2008 were analyzed. The LCU phenomenon was defined as secondary revascularization 1 year after index stenting. Retreatment for very late stent thrombosis was considered as part of the LCU phenomenon.

RESULTS

Incidence of the LCU phenomenon was seen in 33 patients (3.6%). Very late stent thrombosis was observed in 5 patients (0.6%) and very late in-stent restenosis was observed in 28 patients (3.0%). At the 12-month landmark analysis, the cumulative rate of cardiac death was significantly higher in patients with the LCU phenomenon than in those without any target lesion revascularization (9.0% vs. 0.9%, p<0.001). In the multivariate analysis, hemodialysis [odds ratio (OR) 6.07, p=0.003], number of stents (OR 1.58, p=0.02), and coronary bifurcation lesions (OR 2.06, p=0.048) were identified as independent predictors of the LCU phenomenon.

CONCLUSION

The LCU phenomenon is associated with serious consequences and adverse events and remains an important issue in modern practice, despite medical advances. DES should be deployed with a minimum number of stents, and special consideration must be given to patients on hemodialysis and those with coronary bifurcation lesions.

Very late stent thrombosis after paclitaxel-eluting stent implantation with full neointimal tissue coverage visualized by optical coherence tomography

We present findings of a very late stent thrombosis (VLST) involving paclitaxel-eluting stents (PESs) that were fully covered by thin neointima, visualized by optical coherence tomography (OCT) in a patient receiving dual antiplatelet therapy. A 69-year-old Japanese man had been treated with 2 overlapping PESs for chronic coronary artery disease in the proximal right coronary artery. A follow-up coronary computed tomography angiography showed no restenosis in the stent site, and the result of stress myocardial perfusion imaging showed no ischemic changes. Seventeen months after the percutaneous coronary intervention, he was transported to our clinic with a diagnosis of acute myocardial infarction. Emergency coronary angiography showed a total occlusion at the overlapping site of the 2 PESs. After thrombus aspiration therapy, the OCT image revealed a thin layer of neointimal tissue covering the stent struts with no stent malapposition or fracture. There was no plaque rupture site or intracoronary thrombus. Histopathologic study of an aspirated red thrombus revealed massive amounts of inflammatory infiltrates including eosinophils and neutrophils within the fibrin clot. These findings suggested the possibility that the patient's allergic and inflammatory reactions may have caused the onset of VLST. <Learning objective: To recognize the relationship between in stent OCT findings of neointima and pathological findings of the thrombus at the VLST after PES implantation.>.

Very late stent thrombosis at 2.5 years after sirolimus-eluting stent implantation with prior angioscopic image of culprit lesion: A case report

Although very late stent thrombosis after drug-eluting stent implantation is a critical event, its cause has not been clarified. This is the first report of a case with very late stent thrombosis after drug-eluting stent implantation for which prior angioscopic image of the culprit lesion is available. A 54-year-old Japanese male patient with stable angina who received implantation of sirolimus-eluting stent at the culprit lesion and 1-year follow-up angiographic and angioscopic examinations came back with chest pain at rest at 2.5 years after the stent implantation. Very late stent thrombosis was diagnosed by emergent angiographic and angioscopic examinations and was treated by zotarolimus-eluting stent. One-year angiographic and angioscopic follow-up examinations after zotarolimus-eluting stent were performed. Angioscopy revealed uncovered stent strut, yellow plaques, and thrombus at 1-year follow-up after sirolimus-eluting stent implantation, and it confirmed the thrombotic occlusion inside the sirolimus-eluting stent at the time of emergent catheterization. This is a case of very late stent thrombosis in the drug-eluting stent where uncovered stent strut, yellow plaques, and thrombus had been detected by angioscopy 1.5 years before the onset. Those thrombogenic sources might be the cause of stent thrombosis.

Very late stent thrombosis after drug-eluting stent implantation in a patient with antiphospholipid syndrome

A 74-year-old woman was admitted to our hospital with chest pain and shortness of breath. Coronary arteriograms revealed occlusion of a drug-eluting stent, which had been implanted 33 months earlier, in the middle right coronary artery. During percutaneous coronary intervention, distal embolization developed and a thrombus was detected with an aspiration catheter. Serological examinations performed 1 year before and during the present hospitalization revealed positive lupus anticoagulant activity. Thrombophilic tendencies, such as antiphospholipid syndrome, are noteworthy as one of the causative factors in very late stent thrombosis.