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Introduction and Objectives: Stent thrombosis (ST) is a life-threatening complication after stent implantation. Intravascular ultrasound is able to discern most causes of ST. The aim of this study was to compare intravascular ultrasound findings between bare-metal stents (BMS) and drug-eluting stents (DES) in patients with late (31 days to 1 year) or very late ST (> 1 year)., Methods: Of 250 consecutive patients with late or very late ST in 7 Spanish institutions, 114 patients (45.5% BMS and 54.5% DES) were imaged with intravascular ultrasound. Off-line intravascular ultrasound analysis was performed to assess malapposition, underexpansion, and neoatherosclerosis., Results: The median time from stent implantation to ST was 4.0 years with BMS and 3.4 years with DES (P = .04). Isolated malapposition was similarly observed in both groups (36.5% vs 46.8%; P = .18) but was numerically lower with BMS (26.6% vs 48.0%; P = .07) in patients with very late ST. Isolated underexpansion was similarly observed in both groups (13.5% vs 11.3%; P = .47). Isolated neoatherosclerosis occurred only in patients with very late ST and was more prevalent with BMS (22.9%) than with DES (6.0%); P = .02. At 2.9 years' follow-up, there were 0% and 6.9% cardiac deaths, respectively (P = .06) and recurrent ST occurred in 4.0% and 5.2% of patients, respectively (P = .60)., Conclusions: Malapposition was the most common finding in patients with late and very late ST and is more prevalent with DES in very late ST. In contrast, neoatherosclerosis was exclusively observed in patients with very late ST and mainly with BMS., (Copyright © 2017 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.)

Aims: Our aim was to describe the intravascular ultrasound (IVUS) findings of patients with late stent thrombosis (ST) undergoing percutaneous intervention, and to compare the pre- and post-intervention IVUS findings of patients treated with balloon angioplasty (BA) vs. additional stent implantation (ASI)., Methods and Results: A total of 117 patients with late ST imaged with IVUS were included (51.2% had drug-eluting stent ST). Treatment was left to the operator's discretion: BA was performed in 53.8% and ASI in 46.2%. Pre-intervention, incomplete stent apposition (ISA) was observed in 69.8% vs. 63.0% (p=0.43), underexpansion in 33.3% vs. 18.5% (p=0.07) and restenosis in 15.9% vs. 27.8% (p=0.12), respectively. Post-intervention, persistent ISA was observed in 37.2% vs. 60.9% (p=0.03) and malapposition volume decreased by 43.6% vs. 2.6% (p=0.03). Persistent underexpansion was observed in 9.3% vs. 17.4% (p=0.26); however, the stent expansion index was largely increased with BA (from 0.75 to 0.88) compared to ASI (from 0.80 to 0.82); p=0.046. At two years, recurrent ST was observed in one (1.7%) vs. four (7.7%) patients, respectively; p=0.09., Conclusions: Non-optimal IVUS criteria of stent implantation are often observed in patients with late ST. Treatment of late ST with BA leads to a larger reduction of malapposition and underexpansion with respect to ASI and is associated with favourable outcomes.

Background: Some modifications introduced in the design of the new generation of drug-eluting stent (DES) to improve their flexibility may entail a reduction in their longitudinal strength. This study sought to evaluate the longitudinal deformation of DESs by multislice computed tomography (MSCT)., Methods: This study included DESs that could have been potentially deformed by mechanical actions such as: (1) catheter impingement; (2) postdilation; (3) kissing balloon; and (4) intravascular imaging after implantation. Patients on atrial fibrillation or with overlapping stents were excluded. All patients underwent stent length evaluation by MSCT 9-12 months after implantation., Results: Forty-five stents were included: 15 platinum chromium (PtCr-DES), 15 cobalt chromium (CoCr-DES), and 15 stainless-steel (SS-DES). The relative longitudinal deformation by stent type was 6.93 ± 5.82% for PtCr-DES, 6.19 ± 5.79% for CoCr- DES, and 4.03 ± 4.07% for SS-DES (P=.31). Among the mechanical actions studied, only catheter impingement was related to longitudinal stent deformation (P<.01). After adjustment, only catheter impingement (P<.01) and nominal stent length (P=.049) were independently related to longitudinal deformation. There were no stent fractures., Conclusions: Longitudinal deformation of DESs is common in all the studied platforms when subject to longitudinal forces. Guiding catheter impingement is the only mechanical action significantly associated with DES shortening.

Objectives: To assess the usefulness of the MGuard stent in patients with ST-segment elevation myocardial infarction (STEMI) in whom a high thrombus burden persists after manual aspiration., Background: In some patients with STEMI, a high thrombus burden may persist after manual aspiration. These patients may be at high risk of distal embolization and therefore impaired myocardial reperfusion. The MGuard is a novel mesh-covered stent designed to minimize thrombus embolization., Methods: Single-arm, prospective registry of patients with STEMI and high thrombus burden after aggressive thrombus aspiration treated with the MGuard stent. High thrombus burden was defined as thrombus burden grade 4 or 5 according to the TIMI score. Lesions with a side branch ≥2 mm and patients with cardiogenic shock were not included. The study end-points were proportion of final TIMI 3 flow, normal myocardial blush, and complete ST-segment resolution., Results: Fifty-six patients were included. After MGuard stent implantation >85% of cases had thrombus score = 0. Final TIMI 3 flow was achieved in 82% of cases, normal myocardial blush in 55%, and complete ST-segment resolution in 59%. Occlusion of a side branch (<2 mm) occurred in 2 cases (3.5%), embolization to a distal branch in 5 cases (8.9%), and transient no-reflow in 4 cases (7.1%). Major adverse cardiac events rate at 9 months was 3.6%, including 1 definite acute stent thrombosis and 1 target-vessel revascularization., Conclusions: The MGuard stent may be useful to prevent distal embolization in patients with STEMI and high thrombus burden despite mechanical aspiration., (© 2013, Wiley Periodicals, Inc.)

Introduction and Objectives: Percutaneous coronary intervention is recommended in patients with unprotected left main stenosis non suitable for coronary artery bypass graft. Long-term follow-up of those patients remains uncertain., Methods: All patients with de novo unprotected left main stenosis treated with stent implantation were consecutively enrolled. Percutaneous coronary intervention was indicated according to the standards of care, taking into account clinical and anatomical conditions unfavorable for coronary artery bypass graft. The primary end point was the occurrence of major adverse cardiac events, a composite of death, nonfatal acute myocardial infarction, or target lesion revascularization., Results: Of 226 consecutive patients included, 202 (89.4%) were treated with drug-eluting stents. Mean age was 72.1 years, 41.1% had renal dysfunction, and mean Syntax score and EuroSCORE were 28.9 and 7.4, respectively. Angiographic and procedural success was achieved in 99.6% and 92.9% of patients. At 3 years, the rates of major adverse cardiac events, death, nonfatal acute myocardial infarction and target lesion revascularization were 36.2%, 25.2%, 8.4%, 8.0%, respectively. Target lesion revascularization was more frequently observed when ≥ 2 stents were implanted rather than a single stent (18.5% vs 5.8%, P=.03); and with bare metal stents rather than drug-eluting stents (13.0% vs 7.9%, P=.24). Definite stent thrombosis was observed in 2 patients (0.9%) and probable stent thrombosis in 7 (3.1%). Female sex, impaired left ventricular function, and use of bare metal stents were significantly related with all-cause mortality., Conclusions: High-risk patients with unprotected left main stenosis treated with percutaneous coronary intervention presented with a high rate of major adverse cardiac events at long-term follow-up. Female sex, impaired left ventricular function, and use of bare metal stents were predictors of poor prognosis., (Copyright © 2011 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.)