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Eurointervention | 2012
Robert J. Gil; Dobrin Vassilev; Aleksandra Michałek; Adam Kern; Radoslaw Formuszewicz; Sławomir Dobrzycki; Jarosław Wójcik; Maciej Lesiak; Piotr Kardaszewicz; Andrzej Lekston
AIMS Dedicated bifurcation stents seem to be the most promising solution for treating bifurcations. The aim of our study was to present the 12 months results of a new dedicated stent for coronary bifurcation lesions -the paclitaxel-eluting stent- BiOSS® Expert (Bifurcation Optimisation Stent System, Balton, Warsaw, Poland). METHODS AND RESULTS Sixty-three patients with 65 lesions were enrolled in the registry. Forty-six % of the patients were classified as NSTEMI or unstable angina, 27% were diabetics, 30% had previous myocardial infarction and 48% had a history of previous revascularisation. In addition, hypertension and dyslipidaemia were the most common risk factors (58% and 40%). Sixty-five stents were successfully implanted (100% device success rate). The analysis of 30 days follow-up for 63 patients revealed good clinical results showing lack of death, target lesion revascularisation procedures (TLR) and target vessel revascularisation procedures (TVR). There were six (9,5%) cases of in-hospital raised troponin, however, only one showed an additional increase in CK-MB levels and was qualified as non-Q myocardial infarction (MI). There was a need for percutaneous coronary intervention (PCI) in a non-index vessel in one patient due to exertional angina. The analysis of 12-month follow-up for 63 patients revealed good clinical results. There were two (3.2%) cases of death (three and 10 months after index procedure). The first patient, in good physical shape, drowned, while the second was found dead by his family. There were no incidents of MI or stroke in the rest of the population. At 12 months there were seven (10.8% per lesion; 11.1% per patient) cases of TLR and nine (13.8% per lesion; 14.3% per patient) TVR. There were also 15 (23.8%) cases of PCI on vessels not related to BiOSS® Expert stent implantation. CONCLUSIONS Our registry showed that bifurcation treatment with a single dedicated paclitaxel-eluting bifurcation stent, BiOSS® Expert is feasible and successful. The long-term clinical results are satisfactory in this high-risk patient population.
Journal of Interventional Cardiology | 2014
Jacek Bil; Robert J. Gil; Dobrin Vassilev; Jarosław Rzezak; Tomasz Kulawik; Tomasz Pawłowski
OBJECTIVES The aim of this study was to assess prospectively the effectiveness and safety profile of distal left main stem (LMS) stenosis treatment with dedicated bifurcation paclitaxel-eluting stent BiOSS Expert®. BACKGROUND Angioplasty of distal LMS stenosis is always a high-risk procedure, and optimal treatment is uncertain. METHODS This was a prospective international 2-center study, which enrolled patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) or stable angina with distal left main stenosis. All patients were treated with the dedicated bifurcation stent BiOSS Expert®. Provisional T-stenting was the obligatory strategy. Angiographic control was performed after 12 months. The primary end-point was cumulative rate of death, myocardial infarction (MI), and target lesion revascularization (TLR) at 12 months. Angiographic end-points included late lumen loss, percent diameter stenosis, and binary restenosis rate. RESULTS A total of 54 patients with distal LMS stenosis were enrolled. Seven patients (13%) were enrolled during NSTE-ACS, 77.8% were hypertensive, 27.8% were diabetic, 51.9% had previous MI, 53.7% underwent prior percutaneous coronary intervention, and 16.7% coronary artery bypass graft. The mean SYNTAX score was 21.52 ± 6.50. The device success rate was 100%. The mean BiOSS Expert stent parameters were as follows: 4.07 ± 0.26 mm × 3.36 ± 0.26 mm × 16.61 ± 1.72 mm and in side branch the other stent (classical drug-eluting stent) was implanted in 25.9% of cases. The overall TLR was 9.3%. There were no death, stent thrombosis, or acute MI. In the univariate regression analysis, the only factor associated with higher risk for TLR was the SYNTAX score value. CONCLUSIONS The dedicated bifurcation stent BiOSS Expert® proved to be a feasible device, with promising safety and long-term clinical effectiveness in the treatment of distal LMS stenosis.
Eurointervention | 2011
Dobrin Vassilev; Robert J. Gil; Krzysztof Milewski
AIMS The optimal treatment strategy for coronary bifurcation lesions is still unknown. The BiOSS Lim stents (Bifurcation Optimisation Stent System) is a novel dedicated bifurcation stent introduced over a single wire in to the main vessel, covered with biodegradable polymer and sirolimus. It has wider proximal and narrower distal parts. The aim of the study was to assess applicability of the the BiOSS Lim stent in a porcine coronary model. METHODS AND RESULTS A total of 14 BiOSS Lims were implanted in normal non-atherosclerotic porcine coronary bifurcations of 14 animals (six stents for 28 days, eight stents for 90 days) using 1.1:1.0 stent-to-artery ratio. Stent geometry and morphology were evaluated by Faxitron imagery (Faxitron Bioptics, LLC, IL, USA). Vascular effects were assessed based on angiographic and histological analysis. Analysis of Faxitron images revealed no major abnormalities except two struts fractures at the place of connection between the mid-portion and proximal wider part of the stent. Histomorphometry showed decreased area stenosis and intimal thickness at 90 days compared with the 28 days cohort. The inflammatory scores were low (<1) at both time points and struts endothelialisation was completed at 28 days. CONCLUSIONS The novel BiOSS Lim stent demonstrates good short- and mid-term vascular effects in a porcine coronary bifurcation model.
Eurointervention | 2016
Robert J. Gil; Jacek Bil; Maik J. Grundeken; Adam Kern; Luis A. Iñigo Garcia; Dobrin Vassilev; Tomasz Pawłowski; Radoslaw Formuszewicz; Sławomir Dobrzycki; Joanna J. Wykrzykowska; Patrick W. Serruys
AIMS The aim of the POLBOS II randomised trial was to compare any regular drug-eluting stents (rDES) with the dedicated bifurcation sirolimus-eluting stent BiOSS LIM for the treatment of coronary bifurcation lesions. The secondary aim was to study the effect of final kissing balloon inflation (FKBI) on clinical outcomes. METHODS AND RESULTS Between December 2012 and December 2013, 202 patients with stable coronary artery disease or non-ST-segment elevation acute coronary syndrome were randomly assigned 1:1 to treatment of the coronary bifurcation lesions either with the BiOSS LIM stent (n=102) or with an rDES (n=100). Coronary re-angiography was performed at 12 months. The primary endpoint was the composite of cardiac death, myocardial infarction (MI), and target lesion revascularisation (TLR) at 12 months. The target vessel was located in the left main in one third of the cases (35.3% in BiOSS and 38% in rDES). Side branch treatment was required in 8.8% (rDES) and 7% (BiOSS). At 12 months, the cumulative MACE incidence was similar in both groups (11.8% [BiOSS] vs. 15% [rDES, p=0.08]), as was the TLR rate (9.8% vs. 9% [p=0.8]). The binary restenosis rates were significantly lower in the FKBI subgroup of the BiOSS group (5.9% vs. 11.8%, p<0.05). CONCLUSIONS MACE rates as well as TLR rates were comparable between the BiOSS LIM and rDES. At 12 months, cumulative MACE incidence was similar in both groups (11.8% vs. 15%), as was the TLR rate (9.8% vs. 9%). Significantly lower rates of restenosis were observed in the FKBI subgroup of the BiOSS group.
Jacc-cardiovascular Interventions | 2012
Bon-Kwon Koo; Seung-Pyo Lee; JuHee Lee; Kyung-Woo Park; Jung-Won Suh; Young-Seok Cho; Woo-Young Chung; Joon-Hyung Doh; Chang-Wook Nam; Cheol Woong Yu; Bong-Ki Lee; Dobrin Vassilev; Robert J. Gil; Hong-Seok Lim; Seung-Jea Tahk; Hyo-Soo Kim
OBJECTIVES This study sought to investigate the clinical, electrocardiographic, and physiological relevance of main and side branches in coronary bifurcation lesions. BACKGROUND Discrepancy exists between stenosis severity and clinical outcomes in bifurcation lesions. However, its mechanism has not been fully evaluated yet. METHODS Sixty-five patients with left anterior descending coronary artery (LAD) bifurcation lesions were prospectively enrolled. Chest pain and 12-lead electrocardiogram were assessed after 1-min occlusion of coronary flow and coronary wedge pressure (Pw) was measured using a pressure wire. RESULTS ST-segment elevation was more frequent during LAD occlusion (92%) than during diagonal branch occlusion (37%) (p < 0.001). Pain score was also higher with the occlusion of LAD than with the diagonal branch (p < 0.001). However, both Pw and Pw/aortic pressure (Pa) were lower in the LAD than in diagonal branches (Pw: 21.0 ± 6.5 vs. 26.7 ± 9.4, p < 0.0001; Pw/Pa: 0.22 ± 0.07 vs. 0.27 ± 0.08, p = 0.001). The corrected QT interval was prolonged with LAD occlusion (435.0 ± 39.6 ms to 454.0 ± 45.4 ms, p < 0.0001) but not with diagonal branch occlusion. There was no difference in vessel size between the diagonal branches with and without ST-segment elevation during occlusion. Positive and negative predictive values of vessel size (≥2.5 mm) to determine the presence of ST-segment elevation were 48% and 72%, respectively. CONCLUSIONS Diagonal branch occlusion caused fewer anginas, less electrocardiogram change, less arrhythmogenic potential, and higher Pw than did a LAD occlusion. These differences seem to be the main mechanism explaining why aggressive treatment for side branches has not translated into clinical benefit in coronary bifurcation lesions. (Comparison Between Main Branch and Side Branch Vessels; NCT01046409).
Journal of Geriatric Cardiology | 2014
Gianluca Rigatelli; Mariano Palena; Paolo Cardaioli; Fabio Dell'Avvocata; Massimo Giordan; Dobrin Vassilev; Marco Manzi
Objectives To assess the impact on stent implantation rate and mid-term outcomes of prolonged high pressure angioplasty of femoropopliteal lesions. Methods We retrospectively enrolled 620 consecutive patients from January 2011 to December 2011 (75.6 ± 12.3 years, 355 males, 76.5% in Rutherford class 5–6), referred for critical limb ischemia and submitted to prolonged high-pressure angioplasty of femoropopliteal lesions. The definition of prolonged high-pressure angioplasty includes dilation to at least 18 atm for at least 120 s. Procedural data, and clinical and instrumental follow-up were analyzed to assess stent implantation rate and mid-term outcomes. Results The preferred approach was ipsilateral femoral antegrade in 433/620 patients (69.7%) and contralateral cross-over in 164/620 (26.4%) and popliteal retrograde + femoral antegrade in 23/620 (3.7%). Techniques included subintimal angioplasty in 427/620 patients (68.8%) and endoluminal angioplasty in 193/620 patients (31.2%). The prolonged high pressure balloon angioplasty procedure was successful in 86.2% (minor intra-procedural complications rate 15.7 %), stent implantation was performed in 74 patients (11.9%), with a significant improvement of ankle-brachial index (0.29 ± 0.6 vs. 0.88 ± 0.3, P < 00.1) and Rutherford class (5.3 ± 0.8 vs. 0.7 ± 1.9, P < 0.01), a primary patency rate of 86.7%, restenosis of 18.6 % on Doppler ultrasound and a target lesion revascularization of 14.8% at a mean follow-up of 18.1 ± 6.4 months (range 1–24 months). Secondary patency rate was 87.7%. Conclusions Prolonged high pressure angioplasty of femoropopliteal lesions appears to be safe and effective allowing for an acceptable patency and restenosis rates on mid-term.
Cardiovascular Revascularization Medicine | 2014
Gianluca Rigatelli; Paolo Cardaioli; Fabio Dell’Avvocata; Massimo Giordan; Dobrin Vassilev; Chiara Fraccaro; Loris Roncon; Giuseppe Faggian
OBJECTIVES Restenosis after drug eluting stent (DES) implantation in the distal/bifurcation left main (DBLM) remains challenging to manage. The aim of this study was to assess the in-stent restenosis (ISR) after DES implantation in DLM and to evaluate current management strategy. METHODS The medical records of patients referred for LM distal/bifurcation percutaneous coronary interventions (PCI) from the same Cardiology Unit in the January 2007 to December 2012 period were reviewed for PCI technique, stent type, restenosis type, restenosis treatment and management (CABG, balloon angioplasty only, alternative DES implant, drug eluting balloon angioplasty). RESULTS Fourteen patients (5 females, mean age 75.1±8.3years) out of 89 (15.7%) having undergone a percutaneous coronary interventions on DBLM with DES, developed restenosis (everolimus stents in 10 patients, zotarolimus stents in 4 patients). Technique used at the first implant included stenting of the main branch in 4 patients, culottes stenting in 6 patients and T-stent in 4 patients. The mean time elapsed from the first angioplasty and ISR intervention was 7.6±3.6months. Restenosis treatments included: implantation of a different DES (in 3 patients), implantation of a bare-metal stent (in 2 patients), simple balloon angioplasty (in 4 patients), and drug-eluting balloon (5 patients). At 6-month angiographic control second restenosis rate was 14.2%. After a mean follow-up of 38.5±24.4months the target vessel revascularization was 14.3%: surgery was the final choice in two patients due to recurrent restenosis. Incidence of major adverse cardiac event was 28.5%. CONCLUSIONS The occurrence of restenosis after DBLM following DES implantation is not frequent but remains difficult to manage. In our small anecdotal series, all the different strategies including implantation of different DES, balloon angioplasty, bare-metal stent implantation and drug-eluting balloon angioplasty appeared equally effective in maintaining arterial patency.
Jacc-cardiovascular Interventions | 2014
Dobrin Vassilev; Gianluca Rigatelli; Ana Kaneva-Nencheva; Elisaveta Levunlieva; Alexander Alexandrov
A 16-year-old boy with severe coarctation of the aorta with hypoplastic arch and subvalvular aortic stenosis had been operated on at 2 and 7 years of age for coarctation repair and subaortic stenosis relief. Recoarctation developed at 10 years of age, and he underwent aortic stenting with a CP Stent
Cardiovascular Revascularization Medicine | 2017
Gianluca Rigatelli; Marco Zuin; Fabio Dell'Avvocata; Dobrin Vassilev; Ramesh Daggubati; Thach Nguyen; Nguyen Van Viet Thang; Nicolas Foin
BACKGROUND/PURPOSE Computational fluid dynamics (CFD) have been recently adopted in many fields of cardiovascular medicine and in interventional cardiology. Using CFD analysis we compared the use of different PCI procedures, with and without the utilization of a proximal optimization technique (POT), on a complex coronary artery bifurcation. METHODS/MATERIALS For the analysis, we considered a hypothetic model of a left anterior descending artery-diagonal Medina 1,1,1 bifurcation type with a diameter of the proximal main branch (MB) and the side branch (SB) set at 3.5mm and 2.5mm, respectively. The bifurcation angle has been set to 50°. For the stent simulation, we reconstructed a third-generation, ultra-thin strut everolimus-eluting stent (ORSIRO stent, Biotronik IC, Bulack, Switzerland). RESULTS The Nano-crush and the modified T techniques seem able to restore the most physiologic fluid dynamic profile. Conversely, the DK-crush and the culotte demonstrated an intermediate and worst effect, respectively. The addition of a final POT resulted favorably for both Nano-crush and reverse modified T techniques, whereas a neutral and lack of significant effects have been observed for the DK-crush and culotte technique, respectively. CONCLUSION Different double-stenting techniques (DST) have a different impact on coronary flow physiology. Both Nano-crush and modified T techniques achieved the most physiologic profile. The addition of a final POT appears to be a favourable step for both Nano-crush and modified T.
Journal of the American College of Cardiology | 2016
Robert J. Gil; Jacek Bil; Dobrin Vassilev; Adam Kern; Natalia Pietraszek; Matylda Kaźmierska; Kamil Humaidi; Maciej Bobko; Luis A. Iñigo-García; Radoslaw Formuszewicz; Sławomir Dobrzycki
The aim of this study was to analyze the outcome predicting factors and long-term results of patients enrolled into two randomized clinical trials POLBOS I (5-year follow-up,[NCT02192840]) and POLBOS II (3-year follow-up,[NCT02198300]). The BiOSS (Balton, Poland) stent is a coronary bottle-