Stent-related defects in patients presenting with stent thrombosis: differences at optical coherence tomography between subacute and late/very late thrombosis in the Mechanism Of Stent Thrombosis (MOST) study

Everolimus-eluting bioresorbable scaffold versus everolimus-eluting metallic stent in primary percutaneous coronary intervention of ST-segment elevation myocardial infarction: a randomized controlled trial

BACKGROUND

Primary percutaneous coronary intervention with implantation of a metallic drug-eluting stent (DES) is the standard treatment for patients presenting with ST-elevation myocardial infarction (STEMI). Implantation of a bioresorbable scaffold (BRS) during STEMI represents a novel strategy without intravascular metal.

OBJECTIVE

The aim of the study was to investigate 12-month healing response in an STEMI population after implantation of either the Absorb BRS or Xience DES (Abbott Vascular, USA).

METHODS

The present trial was a prospective, randomized, controlled, nonblinded, noninferiority study with planned inclusion of 120 patients with STEMI. Patients were randomly assigned 1:1 to treatment with Absorb BRS or Xience DES. Implantation result and healing response were evaluated by angiography and optical coherence tomography (OCT) at baseline and 12-month follow-up. The primary endpoint was minimum flow area (MFA) assessed at 12 months. Coronary stent healing index (CSHI) was calculated from OCT images.

RESULTS

Out of 66 included patients, 58 had follow-up OCT after 12 months, and 49 entered matched analysis. One death occurred in each group; none were stent-related. MFA was 5.13 ± 1.70 mm2 (95% CI, 4.44-5.82) in the BRS group compared with 6.30 ± 2.49 mm2 (95% CI, 5.22-7.37) (P = 0.06) in the DES group. Noninferiority could not be evaluated. CSHI for both groups had a median score of 3.

CONCLUSION

The DES group performed numerically better in primary and secondary endpoints, but the CSHI showed good stent healing in both groups.

Temporal patterns, characteristics, and predictors of clinical outcomes in patients undergoing percutaneous coronary intervention for stent thrombosis

BACKGROUND

There are limited data on the outcomes of percutaneous coronary intervention (PCI) following stent thrombosis (ST) and differences exist based on timing.

AIMS

Our aim was to study the rates of PCI procedures for an ST indication among all patients admitted for PCI at a national level and to compare their characteristics and procedural outcomes based on ST timing.

METHODS

All PCI procedures in England and Wales (2014-2020) were retrospectively analysed and stratified by the presence of ST into four groups: non-ST, early ST (0-30 days), late ST (>30-360 days), very late ST (>360 days). Multivariable logistic regression models were performed to assess the odds ratios (OR) of in-hospital MACCE (major adverse cardiovascular and cerebrovascular events, a composite of mortality, acute stroke and reinfarction) and mortality.

RESULTS

Overall, 7,923 (1.4%) procedures were for ST indication, most commonly for early ST (n=4,171; 52.6%), followed by very late ST (n=2,801; 35.4%) and late ST (n=951; 12.0%). The rate of PCI for ST declined between 2014 and 2020 (1.7 to 1.4%; p<0.001). Early ST was the only subgroup associated with increased odds of MACCE (OR 1.22, 95% CI: 1.05-1.41), all-cause mortality (OR 1.21, 95% CI: 1.07-1.36) and reinfarction (OR 2.48, 95% CI: 1.48-4.14), compared with non-ST indication. The odds of mortality were significantly reduced in ST patients with the use of intravascular imaging (OR 0.66, 95% CI: 0.48-0.92) and newer P2Y12 inhibitors (ticagrelor: OR 0.69, 95% CI: 0.49-0.95; prasugrel: OR 0.54, 95% CI: 0.30-0.96).

CONCLUSIONS

PCI for ST has declined in frequency over a 7-year period, with most procedures performed for early ST. Among the different times of ST onset, only early ST is associated with worse clinical outcomes after PCI. Routine use of intravascular imaging and newer P2Y12 inhibitors could further improve outcomes in this high-risk procedural group.

Impact of Intracoronary Imaging-Guided Percutaneous Coronary Intervention on Procedural Outcomes Among Complex Patient Groups

Background Intracoronary imaging (ICI) has been shown to improve survival after percutaneous coronary intervention (PCI). Whether this prognostic benefit is sustained across different indications remains unclear. Methods and Results All PCI procedures performed in England and Wales between April, 2014 and March 31, 2020, were retrospectively analyzed. The association between ICI use and in-hospital major acute cardiovascular and cerebrovascular events; composite of all-cause mortality, stroke, and reinfarction and mortality was examined using multivariable logistic regression analysis for different imaging-recommended indications as set by European Association for Percutaneous Cardiovascular Interventions consensus. Of 555 398 PCI procedures, 10.8% (n=59 752) were ICI-guided. ICI use doubled between 2014 (7.8%) and 2020 (17.5%) and was highest in left main PCI (41.2%) and lowest in acute coronary syndrome (9%). Only specific European Association for Percutaneous Cardiovascular Interventions imaging-recommended indications were associated with reduced major acute cardiovascular and cerebrovascular events and mortality, including left main PCI (odds ratio [OR], 0.45 [95% CI, 0.39-0.52] and 0.41 [95% CI, 0.35-0.48], respectively), acute coronary syndrome (OR, 0.76 [95% CI, 0.70-0.82] and 0.70 [95% CI, 0.63-0.77]), and stent length >60 mm (OR, 0.75 [95% CI, 0.59-0.94] and 0.72 [95% CI, 0.54-0.95]). Stent thrombosis and renal failure were associated with lower mortality (OR, 0.69 [95% CI, 0.52-0.91]) and major acute cardiovascular and cerebrovascular events (OR, 0.77 [95% CI, 0.60-0.99]), respectively. Conclusions ICI use has more than doubled over a 7-year period at a national level but remains low, with <1 in 5 procedures performed under ICI guidance. In-hospital survival was better with ICI-guided than angiography-guided PCI, albeit only for specific indications.

Long-term (beyond 5 years) clinical impact of Xience everolimus-eluting stent implantation

OBJECTS

We aim at examining the long-term clinical outcome after Xience everolimus-eluting stent (X-EES) implantation.

BACKGROUND

Long-term clinical outcomes beyond 5 years after X-EES implantation remain unclear.

METHODS

This retrospective study has collected data from 1184 consecutive patients, corresponding to 1463 lesions, who were treated with X-EES alone in the Nagoya Heart Center between January 2010 and December 2013. The primary endpoint was the 10-year cumulative incidence of target lesion failure (TLF), defined as cardiac death, target vessel myocardial infarction (MI), and clinically indicated target lesion revascularization (TLR). Definite/probable stent thrombosis (ST) was evaluated as a secondary outcome.

RESULTS

At 10 years, the cumulative incidence of TLF was recorded to be 12.4%, whereas that of cardiac death, target vessel MI, and clinically indicated TLR was at 4.4%, 4.1%, and 7.8%, respectively. The cumulative rate of definite/probable ST was observed to remain low (0.3% at 30 days; 0.3% at 1 year; 0.6% at 5 years; and 1.1% at 10 years). In the multivariate analysis, the risk factors of TLF were insulin-treated diabetes (hazard ratio (HR), 1.93; 95% confidence interval (CI), 1.13-3.29; P = .02), left ventricular dysfunction (HR, 2.28; 95% CI, 1.43-3.62; P < .01), hemodialysis (HR, 2.22; 95% CI, 1.39-3.56; P < .01), prior percutaneous coronary intervention (HR, 1.68; 95% CI, 1.18-2.41; P < .01), peripheral vascular disease (HR, 1.70; 95% CI, 1.07-2.69; P < .01), severe calcification (HR, 2.08; 95% CI, 1.36-3.09; P < .01), and in-stent restenosis (HR, 2.93; 95% CI, 1.64-4.89; P < .01).

CONCLUSIONS

The incidence rates of the long-term adverse effects after X-EES implantation, such as late TLR and ST, were determined to be low in this study; however, they increased over time until 10 years after stent implantation.

Online Co-Registration Of IVUS and OCT

Intravascular imaging using both intravascular ultrasound (IVUS) and optical coherence tomography (OCT) have become important tools in the Interventional Cardiologists armamentarium. However, in some centers, intravascular imaging is not widely employed. A number of reasons for this may exist, including lack of training in the use of intravascular imaging. Co-registration with angiography may be a helpful tool for those beginning to use both IVUS and OCT in the cath lab, and may reduce the learning curve associated with its use. For experienced operators, co-registration can shorten procedure time and lessen contrast use which may be particularly important when performing complex or multivessel PCI. As a research tool, co-registration can allow for accurate comparison of interval intravascular images. In this review, we will discuss how to acquire co-registered images using both IVUS and OCT systems, and the potential advantages of this technology over non-co-registered images, and indeed angiography alone.

Post-Stent Optical Coherence Tomography Findings at Index Percutaneous Coronary Intervention - Characteristics Related to Subsequent Stent Thrombosis

BACKGROUND

The association between unfavorable post-stent optical coherence tomography (OCT) findings and subsequent stent thrombosis (ST) remains unclear. This study investigated the ST-related characteristics of post-stent OCT findings at index percutaneous coronary intervention (PCI).Methods and Results:Fifteen patients with ST onset after OCT-guided PCI (ST group) were retrospectively enrolled. Post-stent OCT findings in the ST group were compared with those in 70 consecutive patients (reference group) without acute coronary syndrome onset for at least 5 years after OCT-guided PCI. The incidence of acute myocardial infarction (AMI) was higher in the ST than reference group (60.0% vs. 17.1%, respectively; P=0.0005). The incidence of incomplete stent apposition (93.3% vs. 55.7%; P=0.0064), irregular protrusion (IP; 93.3% vs. 62.8%; P=0.0214), and thrombus (93.3% vs. 51.4%; P=0.0028) was significantly higher in the ST than reference group. The maximum median (interquartile range) IP arc was significantly larger in the ST than reference group (265° [217°-360°] vs. 128° [81.4°-212°], respectively; P<0.0001). In AMI patients, the incidence of a maximum IP arc >180° was significantly higher in the ST than reference group (100% vs. 58.3%, respectively; P=0.0265).

CONCLUSIONS

IP with a large arc was a significant feature on post-stent OCT in patients with ST.

The association of diabetes mellitus with neointimal formation following deployment of second-generation drug-eluting stents: an optical coherence tomographic study

OBJECTIVES

The purpose of this study was to evaluate the association of diabetes mellitus (DM) with neointimal formation after implantation of second-generation drug-eluting stent (DES) visualized by optical coherence tomography (OCT).

METHODS

Patients with single de novo coronary artery disease treated with second-generation DES between June 2014 and June 2017 in our department underwent OCT examination at 1-year follow-up and were enrolled in this retrospective study. The primary end point was in-stent mean neointimal thickness (MNT), and secondary end points included uncovered stent strut, minimal lumen area (MLA), neointimal burden, neointimal hyperplasia (NIH) patterns and stent thrombosis (ST) after 1 year of OCT follow-up.

RESULTS

A total of 68 patents with DM (DM group) and 216 patients without DM (non-DM group) were enrolled. At 1-year follow-up, the DM group compared with the non-DM group, showed: MNT [160 (85-245) μm vs. 120 (60-220) μm, P = 0.038] and neointimal burden [21.4 (8.3-30.1)% vs. 14.0 (5.7-26.1)%, P = 0.023] to be significantly increased. Concurrently, MLA [4.60 (3.53-6.06) mm vs. 5.76 (4.28-7.20) mm2, P = 0. 0.002] was significantly reduced. Interestingly, the degree of uncovered struts (7.3 ± 7.1% vs. 7.7 ± 6.7%, P = 0.704), NIH patterns (P = 0.984), and ST (7.9% vs. 7.4%, P = 0.88) were comparable between the two groups. After propensity score matching, the MNT [160 (90-240) μm vs. 110 (60-220) μm, P = 0.048] and neointimal burden [21.4 (8.3-30.1)% vs. 15.4 (5.6-26.3)%, P = 0.044] remained significantly different in the DM compared to the non-DM group.

CONCLUSION

DM leads to significant increase in MNT and neointimal burden even with second-generation DES, nevertheless stent strut coverage, ST and NIH characteristics remained comparable among the cohorts at 1-year.

Clinical outcomes after percutaneous coronary intervention for early versus late and very late stent thrombosis: a systematic review and meta-analysis

Whether the clinical outcomes of stent thrombosis (ST) are different when stratified by time of occurrence remains unclear. The objective of this study was to compare the short- and long-term clinical outcomes after percutaneous coronary intervention (PCI) for early stent thrombosis (EST) versus late stent thrombosis (LST) and very late stent thrombosis (VLST). We enrolled eligible studies searched from the main electronic databases (EMBASE, PubMed, Cochrane). The primary endpoints were in-hospital, 30-day, 1-year and long-term mortality. The secondary endpoints included recurrent stent thrombosis (RST) and target vessel/lesion revascularization (TVR/TLR) during hospitalization, at 30 days, at 1 year and at long-term follow-up. A total of 23 studies with 17,592 patients were included. Compared with mortality rates of the late and very late thrombosis (LST/VLST) group, in-hospital (P = 0.004), 30-day (P < 0.00001), 1-year (P < 0.00001) and long-term mortality rates (P = 0.04) were significantly higher in the EST group. The in-hospital TVR/TLR rates were similar between the EST group and the LST/VLST group. However, a higher trend in TVR/TLR rate at 30 days and a significantly higher TVR/TLR rate at 1 year (P = 0.002) as well as at long-term follow up (P = 0.009) were found in the EST group. EST patients also trended toward higher risk of RST in both short- and long-term follow-up than LST/VLST patients, although differences were not statistically significant. After PCI treatment, patients with EST have worse clinical outcomes in both short- and long-term follow-up than patients with LST/VLST. Further studies are warranted to determine the optimal treatment strategies for EST.

A scoring system to predict the occurrence of very late stent thrombosis following percutaneous coronary intervention for acute coronary syndrome

We aimed to derive and validate an effective risk score to identify high-risk patients of very late stent thrombosis (VLST), following percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS). Stepwise multivariable Cox regression was used to build the risk model using data from 5,185 consecutive ACS patients treated with PCI (derivation cohort) and 2,058 patients from the external validation cohort. Eight variables were independently associated with the development of VLST: history of diabetes mellitus, previous PCI, acute myocardial infarction as admitting diagnosis, estimated glomerular filtration rate <90 ml/min/1.73 m², three-vessel disease, number of stents per lesion, sirolimus-eluting stent, and no post-dilation. Based on the derived score, patients were classified into low- (≤7), intermediate- (8-9), and high- (≥10) risk categories. Observed VLST rates were 0.5%, 2.2%, and 8.7% and 0.45%, 2.3%, and 9.3% across the 3 risk categories in the derivation and validation cohorts, respectively. High discrimination (c-statistic = 0.80 and 0.82 in the derivation and validation cohorts, respectively) and excellent calibration were observed in both cohorts. VLST risk score, a readily useable and efficient tool to identify high-risk patients of VLST after PCI for ACS, may aid in risk-stratification and pre-emptive decision-making.

Bioabsorbable Drug-Eluting Stent Versus Bare Metal Stent in Iliac Artery Evaluated by Optical Coherence Tomography: An In Vivo Study in Porcine

OBJECTIVE

This study aimed to compare, using optical coherence tomography (OCT), the outcomes of bioabsorbable drug-eluting stent with those of bare metal stent (BMS) following implantation in porcine iliac artery.

METHODS

After the placement of BMS and bioabsorbable drug-eluting stents, we used OCT and digital subtraction angiography to investigate stent appositions, arterial neointima, evagination, and restenosis at 1 and 3 months.

RESULTS

At 1 and 3 months after stent implantation, OCT study was performed to investigate 32 stents and 21 788 struts. Thirty-three malapposed struts were found in the bioabsorbable drug-eluting stent groups and 2 were found in BMS groups. The average neointimal thickness, area, and in-stent stenosis were significantly lower in bioabsorbable drug-eluting stents than in BMS, while the frequency of malapposed struts was higher in the bioresorbable drug-eluting stent groups. Average neointimal thickness was lower in bioabsorbable drug-eluting stents than in BMS at 1 (0.19 ± 0.09 vs 0.67 ± 0.75 mm; P < .001) and 3 months (0.21 ± 0.08 vs 1.52 ± 0.28 mm; P < .001).

CONCLUSION

Our study suggested that bioabsorbable drug-eluting stent is more effective in decreasing arterial restenosis than BMS in animal models.

Lower on-treatment platelet reactivity during everolimus-eluting stent implantation contributes to the resolution of post-procedural intra-stent thrombus: serial OCT observation in the PRASFIT-Elective study

Intra-stent thrombus (IS-Th) formed immediately after percutaneous coronary intervention (PCI) is associated with subsequent adverse coronary events. However, the impact of on-treatment platelet reactivity on IS-Th is unknown. PRASFIT-Elective is a multicenter study of PCI patients receiving prasugrel (20/3.75 mg, loading/maintenance dose) or clopidogrel (300/75 mg), with aspirin (100 mg). Among the 742 study patients, 111 were pre-specified for the OCT sub-study. Of these, 82 underwent OCT immediately after PCI to assess IS-Th and at an 8-month follow-up to evaluate the fate of the IS-Th. Lesions were considered resolved when IS-Th were detected after PCI but not on the follow-up or persistent when IS-Th were observed on both scans. The P2Y12 Reactive Unit (PRU) value was determined at the initial PCI and 4 and 48 weeks post-PCI. In 76 patients (86 lesions), we detected 230 IS-Th initially, and 196 IS-Th (85.2%) were resolved at the 8-month OCT. At PCI, but not 4 or 48 weeks after, the resolved IS-Th group had a lower PRU than the persistent IS-Th group (199 ± 101 vs. 266 ± 102, p = 0.008). Multivariate logistic regression analyses revealed that lower PRU at PCI and less calcified lesions were independent predictive factors for the resolution of IS-Th. Local lesion-related factors and lower on-treatment platelet reactivity at the time of PCI may contribute to the resolution of IS-Th after EES implantation, potentially improving clinical outcome.

Failure Mechanisms and Neoatherosclerosis Patterns in Very Late Drug-Eluting and Bare-Metal Stent Thrombosis

BACKGROUND

There are few clinical studies on the pathophysiological mechanisms of very late stent thrombosis (VLST). We report optical coherence tomography findings in patients with VLST and compare the findings between bare-metal stents (BMS) and drug-eluting stents (DES).

METHODS AND RESULTS

We conducted a registry of stent thrombosis at 4 North American centers with optical coherence tomography imaging programs SAFE registry (The Study of Late Stent Failure Evaluated by OCT). Images were acquired in 61 patients (42 DES and 19 BMS) presenting with definite VLST. The median duration from implantation to VLST presentation was 51.4 months in the DES and 69.9 months in the BMS group (P=0.011). Uncovered and malapposed struts were observed in 70.5% (43/61) and 62.3% (38/61) of patients, respectively, whereas neoatherosclerosis was revealed in 49.2% (30/61). Stent underexpansion was observed in 42.4% of patients. Malapposed struts and stent underexpansion were more frequently demonstrated in DES than in BMS patients, whereas neoatherosclerosis was frequently observed in BMS (40.5% in DES and 68.4% in BMS; P=0.056). The percentage of frames with neoatherosclerosis was lower in DES than in BMS (15.56% [12.24-28.57] versus, 56.41% [40.74-70.00], respectively; P<0.001). Maximum consecutive lipid neointima length was shorter in DES than in BMS (2.4 [1.2-3.6] and 5.3 [3.0-7.0] mm; P=0.011).

CONCLUSIONS

Optical coherence tomography imaging demonstrated that VLST in DES and BMS had a wide variety of abnormal findings, such as neoatherosclerosis, uncovered strut, and malapposed strut. Neoatherosclerosis and lipid neointima were more frequently observed and had more longitudinal extension in BMS compared with DES.

Optical Coherence Tomography Findings in Patients With Stent Thrombosis

INTRODUCTION AND OBJECTIVES

Stent thrombosis (ST) is a rare but potentially serious complication. Optical coherence tomography (OCT) provides high-resolution images and additional information to angiography in the study of this event.

METHODS

Prospective study of patients with ST undergoing reintervention with OCT imaging.

RESULTS

The study included a total of 40 consecutive patients with ST. Mean age was 69 ± 13 years and 83% were male. Early ST (≤ 30 days) was observed in 16 patients and late ST (> 30 days) in 24 patients. Stent thrombosis occurred in 17 bare-metal stents and 23 drug-eluting stents. In 34 patients (85%), adequate OCT images were obtained at the time of the ST. The predominant mechanism in early ST was stent malapposition (39%). In late ST, high frequencies of uncovered (46%) and malapposed struts (17%) were observed, especially in patients with drug-eluting stents. Furthermore, the presence of neoatherosclerosis was very high (67%) in patients with late ST. After intervention, improvements were observed in malapposition length and the amount of residual thrombus.

CONCLUSIONS

OCT allows identification of the underlying mechanisms potentially involved in ST. This imaging modality is helpful in guiding reintervention in these patients, which improves the area and length of malapposition, as well as the maximal residual thrombus area.

Impact of Neointimal Calcifications on Acute Stent Performance during the Treatment of In-Stent Restenosis

Optical coherence tomography (OCT) has become the invasive imaging modality of choice for coronary stent assessment due to its unmatched spatial resolution. Neointimal calcification (NC) is a rare finding, observed in 5-10% of in-stent restenosis (ISR) neointima. The impact of NC on percutaneous coronary intervention of ISR is unknown. We therefore present the outcome of six unique cases of ISR and NC in which OCT was used to evaluate the impact of NC on the quality of stent-in-stent deployment for the treatment of ISR. This series demonstrates for the first time the impact of NC on stent expansion, a finding which might help guiding percutaneous coronary intervention for ISR with NC.

Platelet reactivity over time in coronary artery disease patients treated with a bioabsorbable everolimus-eluting scaffold

Everolimus-eluting bioabsorbable scaffolds (BVSs) have exhibited similar long-term clinical outcomes compared to its everolimus-eluting metallic counterparts. However, reports from earlier studies have shown a signal for an increased rate of stent thrombosis. The aim of the current investigation is to describe the platelet reactivity profiles over time in patients treated with everolimus-eluting BVS in comparison to everolimus-eluting metallic stents. This is a pilot study in which patients on aspirin and clopidogrel with at least 1 everolimus-eluting BVS were included (n = 24). Patients with at least 1 everolimus-eluting metallic stent implanted were included as control group (n = 25). Blood samples were taken at time of discharge and at 3- and 6-month follow-up. Platelet function tests included VerifyNow (VN-P2Y12), multiplate aggregometry (MEA), and light transmission aggregometry (LTA). There was no difference in platelet reactivity at discharge, 3- and 6-month visits (unadjusted p = 0.733 and p = 0.582; p = 0.432 and p = 0.899 after adjusting for discharge value platelet reactivity0, respectively) using VN-P2Y12. Similar findings were observed with LTA. However, patients with BVS showed significantly higher platelet reactivity than patients with metallic stents at 3 and 6 months in the crude analysis (p = 0.003) and after adjusting for discharge value (p = 0.013) measured with ADP-MEA. There were no differences in platelet reactivity mediated by the T × A₂ pathway between both groups. Finally, there is no statistical difference in high on-clopidogrel platelet reactivity (HPR) rate between both groups. The results of this pilot study suggest that BVS might have different platelet reactivity profiles, and warrants further investigation in dedicated clinical studies.

Mechanisms of Very Late Drug-Eluting Stent Thrombosis Assessed by Optical Coherence Tomography

BACKGROUND

The pathomechanisms underlying very late stent thrombosis (VLST) after implantation of drug-eluting stents (DES) are incompletely understood. Using optical coherence tomography, we investigated potential causes of this adverse event.

METHODS AND RESULTS

Between August 2010 and December 2014, 64 patients were investigated at the time point of VLST as part of an international optical coherence tomography registry. Optical coherence tomography pullbacks were performed after restoration of flow and analyzed at 0.4 mm. A total of 38 early- and 20 newer-generation drug-eluting stents were suitable for analysis. VLST occurred at a median of 4.7 years (interquartile range, 3.1-7.5 years). An underlying putative cause by optical coherence tomography was identified in 98% of cases. The most frequent findings were strut malapposition (34.5%), neoatherosclerosis (27.6%), uncovered struts (12.1%), and stent underexpansion (6.9%). Uncovered and malapposed struts were more frequent in thrombosed compared with nonthrombosed regions (ratio of percentages, 8.26; 95% confidence interval, 6.82-10.04; P<0.001 and 13.03; 95% confidence interval, 10.13-16.93; P<0.001, respectively). The maximal length of malapposed or uncovered struts (3.40 mm; 95% confidence interval, 2.55-4.25; versus 1.29 mm; 95% confidence interval, 0.81-1.77; P<0.001), but not the maximal or average axial malapposition distance, was greater in thrombosed compared with nonthrombosed segments. The associations of both uncovered and malapposed struts with thrombus were consistent among early- and newer-generation drug-eluting stents.

CONCLUSIONS

The leading associated findings in VLST patients in descending order were malapposition, neoatherosclerosis, uncovered struts, and stent underexpansion without differences between patients treated with early- and new-generation drug-eluting stents. The longitudinal extension of malapposed and uncovered stent was the most important correlate of thrombus formation in VLST.

Diagnosis and Evaluation of Stent Thrombosis with Optical Coherence Tomography

Stent thrombosis (ST) is a rare complication of percutaneous coronary interventions (PCI), especially with drug-eluting stents. ST presents as acute myocardial infarction requiring emergent repeat PCI; optimal reperfusion occurs in two-thirds of patients. As a result, ST has been associated with a high mortality rate and a high rate of recurrent thrombosis. We discuss the use of optical coherence tomography (OCT) for the diagnosis and evaluation of ST. OCT-guided ST management seems a feasible, safe, and appropriate approach. Intracoronary assesses the efficacy of coronary thrombus removal procedures and detects the prevalent stent-related factor that caused ST.

The usefulness of a perfusion balloon in a case of late stent thrombosis that caused simultaneous double vessel occlusion

Simultaneous stent thrombosis in different coronary arteries requires rapid management. A 70-year-old man experienced simultaneous stent thrombosis at the left anterior descending and circumflex arteries. We used a perfusion balloon to prevent thrombus production at the left anterior descending artery, and completed percutaneous coronary intervention at the left circumflex artery in 10 min. The perfusion balloon was dilated during the procedure. In both vessels, Thrombolysis in myocardial infarction flow grade 3 was achieved after balloon deflation. Thus, use of a perfusion balloon for simultaneous double vessel occlusion helped avoid the need for redundant stent placement and shortened the procedure time.

Eculizumab treatment for paroxysmal nocturnal haemoglobinuria in a patient with recurrent simultaneous multivessel coronary stent thrombosis

We describe a case of recurrent multivessel coronary stent thrombosis in the absence of the typical hallmarks of this phenomenon: (i) discontinuation or poor compliance with double antiplatelet therapy; (ii) stent malapposition and (iii) stent underexpansion. In this case, the recurrence of stent thrombosis was indeed manifestation of a more complex underlying disease, and eventually allowed the clinicians to come to the final diagnosis of paroxysmal nocturnal haemoglobinuria.