Late Catch-up Phenomenon Research Articles

Late Catch-up In-Stent Restenosis and Stent Thrombosis for 2nd Generation Biodegradable Polymer Drug Eluting Stents

Second generation drug-eluting stents (DES) have reduced the rate of in-stent restenosis (ISR) to < 10% [1, 2] in patients undergoing PCI. However, late catch-up in-stent restenosis remains an issue despite the advent in drug-eluting stent technology from 1st to 2nd generation drug eluting stents. The late catch-up phenomenon has been associated with serious consequences and adverse events and remains an important issue in modern practice, despite medical advances with more biocompatible and biodegradable polymers, as well as new therapeutic agents and thinner scaffolds in the development of 2nd generation DES polymer systems. The idea behind biodegradable polymers has been to provide a more controlled elution profile for DES drugs, allowing for long-term therapeutic, but sub-toxic, drug levels in the arterial tissue to prevent ISR and stent thrombosis. However, the late catch-up phenomenon remains an issue resulting in 2ndary revascularization beyond the first year of primary PCI, as it is defined as ISR >1 year. Late stent thrombosis (<1 year) and very late stent thrombosis (>1 year) also remain an issue for biodegradable polymer systems. A long-term presence of the polymer can cause inflammation and thrombogenesis, which is dependent upon polymer degradation kinetics in case of biodegradable polymer DES systems. However, the cause of late catch-up restenosis and stent thrombosis is multi-factorial from a drug-in-polymer formulation perspective of drug release kinetics, e.g., drug elution profile, drug physiochemical properties, and polymer degradation kinetics. It appears that the focus should be on controlling burst release for both late catch-up restenosis and stent thrombosis phenomena.

Diagnostic accuracy of optical coherence tomography for the identification of in-stent fibroatheroma following stent implantation: an ex vivo histological validation study.

The accurate identification of in-stent fibroatheroma by in vivo imaging is clinically important to preventing the late catch-up phenomenon after stent deployment. This study investigated the diagnostic accuracy of optical coherence tomography (OCT) for the detection of "in-stent fibroatheroma" following stent implantation.Fifty stented coronary arteries from the 31 autopsy hearts were examined to compare OCT and histological image findings. A histological in-stent fibroatheroma was defined as a neointima containing an acellular necrotic core generated by macrophage infiltration. OCT-derived in-stent fibroatheroma comprised a heterogeneous pattern with an invisible stent strut behind the low-signal-intensity region.A total of 122 matched OCT and histology cross-sections were evaluated. Using histological findings as the gold standard, the sensitivity, specificity, positive predictive value, and negative predictive value for OCT-derived in-stent fibroatheroma were 100%, 99%, 80%, and 100%, respectively. The only histological finding underlying the false-positive diagnosis of OCT-derived in-stent fibroatheroma was foam cell accumulation without a necrotic core on the neointimal surface. No false-negative diagnosis of OCT for in-stent fibroatheroma was apparent in this analysis.This study demonstrated the potential capability of OCT based on stent strut visualization behind low-signal-intensity regions to discriminate in-stent fibroatheroma from other neointimal tissues.

Early restenosis and late catch-up phenomenon after newer biodegradable- and durable-polymer drug-eluting stent implantations

Abstract Background It is yet to be known whether mechanisms underlying restenosis in newer-generation durable-polymer (DP) and biodegradable-polymer (BP) drug-eluting stents (DES) are different. Purpose This study aims to assess the incidences and predictors of early restenosis and late catch-up phenomenon after newer-generation durable-polymer (DP) and biodegradable-polymer (BP) DES. Methods Between 2010 and 2017, 13858 lesions in 6350 patients were treated with DES (4393 BP-DES, 9465 DP-DES). The early-term (within 1 year) and late-term (from 1 to 2 years) follow-up angiographies were scheduled. Late catch-up phenomenon was defined as in-stent restenosis (ISR) in lesions that evaded ISR within 1 year after stent implantation. ISR was defined as angiographic restenosis of more than 50%. Results The mean patient age was 71 years, and 76.7% were male. Early-term angiographies were performed in 10955 lesions (79.0%). Of those without early-term ISR, late-term angiographies were performed in 7771 lesions (56.1%). The incidences of mid-term restenosis and late catch-up phenomenon were 6.6% and 3.9%, respectively. In the multivariate regression analyses, history of diabetes, hemodialysis and previous PCI were independent predictors of both early restenosis and late catch-up phenomenon. Also, some lesion characteristics such as chronic total occlusion, right coronary artery ostial lesion, small vessel (defined as reference diameter <2.5mm), long lesion (defined as lesion length >30mm) and treatment of ISR lesion were independent predictors of both early restenosis and late catch-up phenomenon. Bifurcation lesion and heavily calcified lesion treated with rotablator were independent risk of early restenosis. Bypass graft lesion was an independent predictor of late catch-up phenomenon. Early restenosis was observed less frequently in DP-DES than in BP-DES (6.3% versus 7.4%, P=0.012). On the contrary, late catch-up phenomenon was observed more frequently in DP-DES than in BP-DES (4.3% versus 2.9%, P=0.026). Conclusions Some lesion characteristics were independent predictors of early restenosis and late catch-up phenomenon after newer-generation DES implantation. The deployment of BP-DES resulted in more early restenosis and less late catch-up phenomenon compared to that of DP-DES. Early Restenosis and Late Catch-Up Funding Acknowledgement Type of funding source: None

P2693Late catch-up phenomenon and late-term target lesion revascularization of two-stenting for coronary bifurcation lesions between first and second generation drug-eluting stents

Abstract Background The second generation drug-eluting stent (G2-DES) has been reported as superior to the first generation drug-eluting stent (G1-DES) in mid-term outcomes. However, the late-term outcomes between G1-DES and G2-DES in two-stenting for coronary bifurcation lesions are not well studied. Purpose To evaluate the late catch-up phenomenon and late-term target lesion revascularization (TLR) of two-stenting for coronary bifurcation lesions between G1-DES and G2-DES. Methods This study included 1133 lesions in 1089 patients undergoing drug eluting stent implantation with two stenting from 2004 to 2016. These consisted of 496 G1-DES implanted lesions and 637 G2-DES implanted lesions. Late-term follow-up angiography was performed without in-stent restenosis (ISR) and TLR at mid-term follow-up in 582 lesions (242 G1-DES lesions and 340 G2-DES lesions). ISR was defined as more than 50% restenosis. Late catch-up phenomenon was defined as ISR without ISR within 1 year following index stent implantation. Late-term TLR was defined as from 1 to 5 year TLR. Bifurcation lesions were defined as the main branch ranging from the proximal stem to the distal main branch with boundaries defined by 5 mm proximal and distal to the stent-implanted area, and the side branch ranging from the bifurcation carina to the distal side branch with boundaries defined by the carina and 5 mm distal to the stent-implanted area. Results The median follow-up duration was 5.1 years (the first and third quarters, 3.2 and 7.1 years). The late-catch up phenomenon rate significantly differed between the G1-DES and G2-DES groups (16.9% vs 8.4%, p=0.001). A significant difference in late catch-up between the same two groups was also observed in bifurcation lesions of the main branch (5.0% vs 0.6%, p=0.001) and side branch (10.3% vs 5.6%, p=0.033), respectively. The 5-year cumulative rates also differed between the two groups in TLR (8.2% vs 3.7% log-rank p=0.001), and late-term TLR (7.0% vs 3.6% log-rank p=0.001). Conclusion Two-stenting using G2-DES, compared with G1-DES, significantly reduced late-term restenosis and TLR. The restenosis rate in bifurcation area may be associated with differences between two groups in late-term outcome.

P2696Clinical characteristics of late catch-up phenomenon after implantation of 2nd generation drug eluting stent

Abstract Introduction Late catch-up phenomenon (LCU) of 1st generation drug eluting stent (DES) has been increasing yearly despite the rate of restenosis in 1 year has reduced compared with bare metal stent (BMS). 2nd generation DES was more improved than 1st generation DES and suggested more benefits about clinical outcome. Purpose To investigate the incidence and predictor of LCU after implantation of 2nd generation DES and to evaluate the association between LCU phenomenon and adverse events. Methods Between August 2012 and July 2013, a total of 1665 consecutive patients (1956 lesions with elective/urgent PCI) were enrolled in SHINANO 5 years Registry (a prospective observational multicenter cohort study) from 13 institutions in Nagano, Japan. 711 patients that were treated with 2nd generation DES and 576 patients with BMS were selected. Exclusion criterias were cases of 1st DES, only POBA, only aspiration and chronic total occulusion. Results There were significant difference about patients background between BMS and 2nd generation DES groups. Those groups were matched with propensity score. After matching, 822 patients (BMS group 411 patients, 2nd generation group 411 patients) were analyzed. The rates of 2nd DES and BMS restenosis 5 years after initial PCI were 9.2% and 8.5% (p=0.572), those of LCU were 2.6% and 5.6% (p=0.043) by 1 year landmark analysis. Cox proportional hazards analysis revealed that the DES in-stent restenosis (ISR) lesion and higher HbA1c were independent predictors for LCU from 1year to 5year (HR 5.304, p=0.009, HR 1.254, p=0.015), but 2nd generation DES was not. Kaplan Meier curve showed no association between LCU phenomenon and all cause death (p=0.446). Cox regression analysis showed LCU was not independent predictor for all cause death (p=0.414). Conclusions Implantation to DES-ISR lesion with 2nd generation DES was associated with higher LCU. Despite of more complex lesions with 2nd generation DES, there were no differences of LCU incidence between 2nd generation DES and BMS. Acknowledgement/Funding None

Risk Factors for Restenosis after Drug-coated Balloon Angioplasty for Complex Femoropopliteal Arterial Occlusive Disease

Currently, there exist limited data on patient outcomes following the use of drug-coated balloons (DCBs) to treat complex femoropopliteal arterial occlusive lesions. The aim of the this study is to investigate the outcomes of patient treated with DCBs and to identify the predictors of restenosis. We retrospectively investigated medical records from 120 patients (137 limbs) treated with DCBs for femoropopliteal lesions at a single center between 2013 and 2016. Primary patency, target lesion revascularization (TLR), and risk factors of restenosis were analyzed. There were 80 de novo and 57 in-stent restenosis lesions. Mean lesion length was 22.2±11.6cm. The clinical primary patency was 85.2% at 1year and 65.3% after 2years. The TLR-free survival rate was 93.0% at 1year and 87.1% after 2years. Critical limb ischemia (CLI; hazard ratio [HR] 5.80, 95% confidence interval [CI] 1.26-26.68, P=0.024) and hypercholesterolemia (HR 4.66, 95% CI 1.30-16.76, P=0.018) were identified as independent predictors of restenosis. In addition, nonuse of cilostazol and popliteal artery involvement showed trends toward an increased risk of restenosis. Treatment with DCBs showed excellent primary patency and TLR-free survival at 1 year after the procedure. However, the primary patency continuously deteriorated beyond 1 year, suggesting a late catch-up phenomenon. The risk of restenosis after treatment with DCBs was significantly associated with CLI and hypercholesterolemia.

3119Comparison of late catch-up phenomenon after second generation DES implantation with bare metal stent implantation assessed by optical coherence tomography

3119Comparison of late catch-up phenomenon after second generation DES implantation with bare metal stent implantation assessed by optical coherence tomography

Paclitaxel-coated balloon plus bare-metal stent for de-novo coronary artery disease: final 5-year results of a randomized prospective multicenter trial.

The PERfECT Stent Study compared paclitaxel-coated balloon (PCB) angioplasty plus bare-metal stent (BMS) implantation with BMS alone in de-novo lesions in native coronary artery disease. Angiographic follow-up after 6 months showed the superiority of the additional PCB. We evaluated a potential late catch-up phenomenon with the use of PCB. In the prospective, multicenter, single-blind, randomized PERfECT Stent trial, 120 patients were assigned to either PCB angioplasty plus BMS implantation or BMS alone. For BMS, the endothelial progenitor cell capturing stent was used. Dual antiplatelet therapy was recommended for 3 months. The clinical endpoint for 5-year follow-up was a composite of cardiac death, myocardial infarction attributed to the target vessel, or target lesion revascularization. The follow-up rate after 5 years was 97%. Baseline and procedural characteristics did not differ. At the 5-year follow-up, clinically driven target lesion revascularization was 23.2% in the BMS group versus 15% with PCB plus BMS (P=0.26). The clinical endpoint (major adverse cardiac event) was 30.4% with BMS and with 23.5% lower with PCB plus BMS. No definite or probable stent thrombosis was found in either group with a dual antiplatelet therapy for 3 months for the total period. PCB angioplasty plus BMS was superior to BMS alone for the treatment of de-novo lesions. The combined clinical endpoint was lower with PCB plus BMS at 6 months and remained lower after 5 years. There was no late catch-up phenomenon (http://www.clinicaltrials.gov; NCT 00732953).

Insulin Resistance as a Predictor of the Late Catch-up Phenomenon After Drug-Eluting Stent Implantation

Percutaneous coronary intervention (PCI) is an effective treatment for patients with ischemic heart disease. In particular, restenosis is suppressed after drug-eluting stent (DES) implantation. However, several problems remain. Previously, we reported neointimal proliferation after DES implantation, which was associated with insulin resistance (IR). The aim of the present study was to clarify whether IR is associated with mortality and major adverse cardiac and cerebrovascular events (MACCE) after 1st-generation DES implantation. We researched the clinical records of 109 patients who had undergone elective PCI and DES implantation between May 2007 and December 2010. We segregated these patients according to the value of the homeostasis model assessment of IR (HOMA-IR) into Group P (n=63; HOMA-IR ≥2.5, positive) and Group N (n=46; HOMA-IR <2.5, negative), and examined the relationship between HOMA-IR and MACCE. The observation period was 7.4±1.6 years. There were no differences between the 2 groups in the occurrence of all-cause death, cardiac death, restenosis, myocardial infarction, stroke, heart failure, or stent thrombosis. However, the late catch-up phenomenon was significantly more common in Group P than in Group N (12.7% vs. 2.2% P=0.048). IR is a useful predictor of the late catch-up phenomenon after DES implantation, and improvement of IR may help to prevent the phenomenon. (Circ J 2016; 80: 657-662).

Abstract 18600: Very Long-term Clinical Outcome After Sirolimus-eluting Stent Implantation

Background: Late adverse events such as stent thrombosis (ST) or late target-lesion revascularization (TLR) after sirolimus-eluting stents (SES) implantation remain an important concern. However, there is little data regarding clinical outcome beyond 5 years after SES implantation. We sought to assess very long-term clinical outcome after SES implantation. Methods: Between April 2004 and December 2006, a total of 686 patients with 894 lesions underwent percutaneous coronary intervention only with SES. We assessed the major adverse cardiac events (MACE), defined as a composite of cardiac death, TLR, definite ST. Results: At 10 years, cumulative incidence of MACE and cardiac death were 50.8% and 8.2%, respectively. Cumulative incidence of TLR within 1 year was 12.6%. However, late TLR beyond 1 year continued to occur without attenuation up to 10 years (2.3%/year) (5 years, 22.8%; 10 years, 33.3%). Cumulative incidence of definite ST was low (30 days, 0.3%; 1 year, 0.9%; 5 years, 1.8%; and 10 years, 3.3%), whereas definite ST also continued to occur without attenuation (0.27%/year). The predictors of MACE were hemodialysis (hazard ratio [HR] 2.87, 95% confidence intervals [CI]:1.76-4.53, p &lt;0.001) and age ≥75 years (HR 1.72, 95% CI: 1.31-2.26, p &lt;0.001). Conclusions: Late catch-up phenomenon regarding ST and TLR continued up to 10 years without attenuation. Careful clinical follow-up is required in patients treated with SES beyond 5 years.

Incidence and Characteristics of Late Catch‐Up Phenomenon Between Sirolimus‐Eluting Stent and Everolimus‐Eluting Stent: A Propensity Matched Study

We evaluated and compared the incidence and characteristics of late catch-up phenomenon (LCU) between everolimus-eluting stent (EES) and sirolimus-eluting stent (SES) implantations. Late catch-up phenomenon after everolimus-eluting stent (EES) implantation has not yet been evaluated sufficiently. Between April 2007 and May 2011, 1,234 patients with coronary artery disease were treated with SES and 502 patients with EES. Following propensity score matching, we evaluated 495 SES-treated patients and 495 ESS-treated patients. The incidences of LCU (i.e., late target lesion revascularization [TLR] [1-3 years]) were compared. The cumulative incidence of TLR at 3 years was 11.9% in the SES group and 6.1% in the EES group (P = 0.001). The incidence of late TLR was 7.5% in the SES group and 3.4% in the EES group (P = 0.004). Even though not statistically significant, intravascular ultrasound showed a higher tendency of stent fracture (SF) in late restenosis lesions in the SES group than in the EES group (37.0% vs 7.7%; P = 0.052). Moreover, the SF rate tended to increase in late restenosis compared with early restenosis (within 1 year) in the SES group compared with the EES group (SES: 37.0% vs 22.2%; P = 0.293, EES: 7.7% vs 10.0%; P = 0.846), although the increase was not significantly different. EES was superior to SES in terms of LCU. SF may be associated with LCU after SES implantation.

0387 : Incidence and predictors of the late catch-up phenomenon after drug-eluting stent implantation

Although clinical restenosis within 1year after percutaneous coronary intervention has been remarkably reduced with the advent of drugeluting 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 DES. A total of 936 lesions treated with DES between June 2002 and June 2010 were analyzed. The LCU phenomenon was defined as secondary revascularization 1 year after index stenting. Incidence of the LCU phenomenon was seen in 103 lesions (11,04%). In the multivariate analysis, severe calcifications [odds ratio (OR) 6.07, p=0.017], restenosis lesion (OR 1.58, p=0.003), and long lesions (OR 2.06, p=0.031) were identified as independent predictors of the LCU phenomenon. The LCU phenomenon is associated with serious consequences and adverse events and remains an important issue in modern practice, despite medical advances. Special consideration must be given to patients with restenosis lesion, long lesions and severe calcifications.

A 2-year follow-up of a randomized multicenter study comparing a paclitaxel drug-eluting balloon with a paclitaxel-eluting stent in small coronary vessels the BELLO study

Background/objectivesA prospective, multi-center, randomized trial, BELLO (Balloon Elution and Late Loss Optimization), showed that the primary endpoint of in-stent (in-balloon) late loss was significantly less with drug-eluting balloons (DEB) as compared with paclitaxel-eluting stents (PES). At 6months, DEB and PES were associated with similar rates of angiographic restenosis, target lesion revascularization (TLR), and major adverse cardiac events (MACE) defined as death, myocardial infarction and target vessel revascularization. The aim of this study was to report 2-year clinical outcomes after treatment of de novo small vessel disease with DEB as compared with PES. MethodsA total of 182 patients were enrolled and randomized to treatment with DEB (n=90) in 94 lesions or PES (n=92) in 98 lesions. The study endpoint was the incidence of MACE at 2-year follow-up. ResultsTwo-year follow-up was achieved in almost all cases (97.8% in DEB group vs. 98.9% in PES group). There was a trend towards a lower incidence of MACE in the DEB group as compared with the PES group (14.8% vs. 25.3%; p=0.08). TLR rates in the DEB group were acceptable at 6months, 1year and 2years and did not differ significantly from the PES group (4.4% vs. 7.6%, p=0.37; 6.7% vs. 12.1%, p=0.23; 6.8% vs. 12.1%, p=0.25, respectively). ConclusionsOur results suggest that treatment of small vessel disease with a paclitaxel DEB is associated with a trend for improved clinical outcomes as compared with PES up to 2years. Late catch-up phenomenon requiring repeat intervention after treatment with DEB was not evident in this study.

Abstract 11911: Comparison of Late Catch-Up Phenomenon Between Sirolimus-Eluting Stent and Everolimus-Eluting Stent During 3 Years Follow-Up - a Propensity Matched Study -

Background: Recent studies have suggested the possibility of late catch-up phenomenon after implantation of sirolimus-eluting stent (SES) for coronary artery disease (CAD) compared to bare metal stent. However, little is known about the incidence of late catch-up phenomenon after implantation of everolimus-eluting stent (EES). Methods: Between April 2007 and May 2011, 1234 patients with CAD were treated with SES and 502 patients were treated with EES in our institution. We used a propensity score matching method with 1:1 matching, including 495 patients treated with SES and 495 patients treated with EES. Late catch-up phenomenon which was defined as target lesion restenosis (1 year to 3 years) were compared between the 2 groups. Results: After the propensity matching, no difference was seen in baseline characteristics between the 2 groups. Cumulative incidence of TLR at 3 years was 7.1% in EES group and 13.5% in SES group (P=0.001, log-rank test). Incidence of late catch-up phenomenon was 4.2% in EES group and 7.8% in SES group (P=0.020, log-rank test). Multivariate Cox’s proportional hazard analysis revealed that sirolimus eluting stent usage (HR 4.7, 95%CI 2.8-7.9, P&lt;0.001), hemodialysis (HR 2.7, 95%CI 1.5-4.9, P=0.001), 2 stent use for bifurcation (HR 2.1, 95%CI 1.1-4.1, P=0.028), IVUS usage (HR 0.41, 95%CI 0.27-0.62, P&lt;0.001), and ACS (HR 1.9, 95%CI 1.0-3.4, P=0.038) were independent predictors of late catch up phenomenon. Conclusions: EES was significantly superior to SES in the incidence of late catch-up phenomenon.

TCT-652 Incidence and Predictors of Late Catch-up Phenomenon After Drug-eluting Stent Implantation

TCT-652 Incidence and Predictors of Late Catch-up Phenomenon After Drug-eluting Stent Implantation

Serial intravascular ultrasound assessment of very late stent thrombosis after sirolimus-eluting stent placement

PurposeIn-stent restenosis has been decreasing through the introduction of drug-eluting stents (DES). On the other hand, adverse events such as very late stent thrombosis (VLST) and late catch-up phenomenon can occur especially with sirolimus-eluting stents (SES, first-generation DES) in long-term follow-up. However, the precise mechanisms underlying VLST have not been well investigated in vivo. Methods and resultsFrom 2004 to 2010, 2034 SES were implanted in 1656 patients and caused eight VLST (0.48% per patient) at Fukuoka Tokushukai Medical Center. Of these, serial intravascular ultrasound (IVUS) images (post-stent implantation and at the time of VLST onset) were obtained from three patients with VLST. Comparing them with eight control patients with SES implanted, the vascular reactivity of VLST patients was analyzed. Eight VLST happened 50±15 months after stent implantation and three of the eight patients with VLST had not taken aspirin daily. There were no differences in minimum stent area, maximum external elastic membrane (EEM) area, and stent edge (distal and proximal) EEM area in post-procedural IVUS images. Compared with the control group patients, ΔEEM area (10.6±3.4mm2 vs. 1.7±1.9mm2, p=0.01) and vessel expansion ratio (185.6±40.3% vs. 112.0±12.1%, p=0.01) were significantly greater in the VLST group based on the greater peri-stent plaque expansion (262.1±72.8% vs. 118.7±21.2%, p=0.01). ConclusionOur serial IVUS study showed that the vascular positive remodeling after SES implantation is one of the most probable morphological mechanisms for VLST development.

Late Adverse Events After Implantation of Sirolimus-Eluting Stent and Bare-Metal Stent

Late adverse events such as very late stent thrombosis (VLST) or late target-lesion revascularization (TLR) after first-generation sirolimus-eluting stents (SES) implantation have not been yet fully characterized at long term in comparison with those after bare-metal stent (BMS) implantation. Among 13 058 consecutive patients undergoing first percutaneous coronary intervention in the Coronary REvascularization Demonstrating Outcome study-Kyoto registry Cohort-2, 5078 patients were treated with SES only, and 5392 patients were treated with BMS only. During 7-year follow-up, VLST and late TLR beyond 1 year after SES implantation occurred constantly and without attenuation at 0.24% per year and at 2.0% per year, respectively. Cumulative 7-year incidence of VLST was significantly higher in the SES group than that in the BMS group (1.43% versus 0.68%, P<0.0001). However, there was no excess of all-cause death beyond 1 year in the SES group as compared with that in the BMS group (20.8% versus 19.6%, P=0.91). Cumulative incidences of late TLR (both overall and clinically driven) were also significantly higher in the SES group than in the BMS group (12.0% versus 4.1%, P<0.0001 and 8.5% versus 2.6%, P<0.0001, respectively), leading to late catch-up of the SES group to the BMS group regarding TLR through the entire 7-year follow-up (18.8% versus 25.2%, and 10.6% versus 10.2%, respectively). Clinical presentation as acute coronary syndrome was more common at the time of late SES TLR compared with early SES TLR (21.2% and 10.0%). Late catch-up phenomenon regarding stent thrombosis and TLR was significantly more pronounced with SES than that with BMS. This limitation should remain the target for improvements of DES technology.

TCT-184 Late Adverse Events After Implantation of Sirolimus-eluting Stent and Bare-metal Stent: 4-7 years follow-up of the CREDO-Kyoto Registry Cohort-2

Background: Late adverse events such as very late stent thrombosis (VLST) or late target-lesion revascularization (TLR) have emerged as new problems after drugeluting stent implantation. However, there is a paucity of data from long-term followup studies evaluating late adverse events after sirolimus-eluting stents (SES) implantation in comparison with bare-metal stent (BMS) implantation. Methods: Among 13058 consecutive patients undergoing first percutaneous coronary intervention in the CREDO-Kyoto registry Cohort-2, 5078 patients were treated with SES only and 5392 patients were treated with BMS only. Median follow-up duration was 1974 (inter-quartile range: 1700-2225) days. Results: During 4-7 years follow-up after SES implantation, VLST and late TLR beyond 1-year occurred constantly and without attenuation at 0.24%/year, and 2.0%/ year, respectively. Cumulative 7-year incidence of VLST was significantly higher in the SES group than in the BMS group (1.43% vs. 0.68%, P<0.0001). However, there was no excess of all-cause death beyond 1-year in the SES group as compared with the BMS group (20.8% vs. 19.6%, P1⁄40.91), although the cumulative incidence of sudden death beyond 1-year was slightly but significantly higher in the SES group than in the BMS group (3.0% vs. 1.8%, P1⁄40.02). Cumulative 7-year incidences of late TLR and clinically-driven late TLR were also significantly higher in the SES group than in the BMS group (12.0% vs. 4.1%, P<0.0001 and 8.5% vs. 2.6%, P<0.0001, respectively), leading to significant late catch-up of the SES group to the BMS group regarding the cumulative incidence of over-all and clinically-driven TLR through 7-year (18.8% vs. 25.2%, and 10.6% vs. 10.2%, respectively). Clinical indication of late TLR in the SES group included acute myocardial infarction (13.1%), unstable angina (8.1%), stable angina (34.0%), asymptomatic ischemia (7.9%) and non-clinically driven (36.9%). Conclusions: During 4-7 years follow-up after SES implantation, late adverse events including VLST and late TLR continued to occur without attenuation of their incidences. Late catch-up phenomenon of SES relative to BMS in terms of TLR was real and should be the target for the development of drug-eluting stents.

TCT-463 Impact of Late Catch-up Phenomenon on Delayed Restenosis After Sirolimus-Eluting Stent and Bare-Metal Stent Implantation

TCT-463 Impact of Late Catch-up Phenomenon on Delayed Restenosis After Sirolimus-Eluting Stent and Bare-Metal Stent Implantation

Late catch-up phenomenon after drug-eluting balloon angioplasty

First generation DIOR (Eurocor, Bonn, Germany) was used in 69% of patients whereas second generation DIOR was used in the remaining subjects. The first generation DIOR consisted in a three-folded balloon with a microporous surface on which paclitaxel was dissolved at a concentration of 3 μg/mm 2 . Successively, this first generation DIOR has been replaced by the second generation DIOR in which paclitaxel is embedded in a matrix consisting of shellac that is a natural bioadhesive polymer providing higher tissue concentration of paclitaxel [7] .A t six months follow-up the rate of TLR in patients presenting with a BMS restenosis and a DES restenosis was 9.2% and 11.5%, respectively whereas