Thin strut bare metal stents in patients with atrial fibrillation: Is there still a need for BMS?

Impact of Coronary Stent Architecture on Clinical Outcomes: Do Minor Changes in Stent Architecture Really Matter?

Introduction

The objective of this study was to compare the accumulated clinical outcomes of two Malaysian all-comers populations, each treated with different polymer-free sirolimus-eluting stents (PF-SES) of similar stent design.

Methods

The Malaysian subpopulation of two all-comers observational studies based on the same protocol (ClinicalTrials.gov Identifiers: NCT02629575 and NCT02905214) were combined and compared to a Malaysian-only cohort which was treated with a later-generation PF-SES. The PF-SES’s used differed only in their bare-metal backbone architecture, with otherwise identical sirolimus coating. The primary endpoint was the accumulated target lesion revascularization (TLR) rate at 12 months. The rates of major adverse cardiac events (MACE), stent thrombosis (ST) and myocardial infarction (MI) were part of the secondary endpoints.

Results

A total of 643 patients were treated with either the first-generation PF-SES (413 patients) or second-generation PF-SES (230 patients). Patient demographics were similar in terms of age (p = 0.744), male gender (0.987), diabetes mellitus (p = 0.293), hypertension (p = 0.905) and acute coronary syndrome (ACS, 44.8% vs. 46.1%, p = 0.752) between groups. There were no differences between treatment groups in terms of lesion length (20.8 ± 7.3 mm vs. 22.9 ± 7.9, p = 0.111) or vessel diameter (2.87 ± 0.39 vs. 2.93 ± 0.40, p = 0.052) despite numerically smaller diameters in the first-generation PF-SES group. The second-generation PF-SES tended to have more complex lesions as characterized by calcification (10.3% vs. 16.2%, p = 0.022), severe tortuosity (3.5% vs. 6.9%, p = 0.041) and B2/C lesions (49.2% vs. 62.8%, p < 0.001). The accumulated TLR rates did not differ significantly between the first- and second-generation PF-SES (0.8% vs. 0.9%, p = 0.891). The accumulated MACE rates were not significantly different (p = 0.561), at 1.5% (6/413) and 2.2% (5/230), respectively.

Conclusions

Modifications in coronary stent architecture which enhance the radial strength and radiopacity without gross changes in strut thickness and design do not seem to impact clinical outcomes.

Clinical Trial Registration

ClinicalTrials.gov Identifiers: NCT02629575 and NCT02905214.

Real-World Dual Antiplatelet Therapy Following Polymer-Free Sirolimus-Eluting Stent Implantations to Treat Coronary Artery Disease

Objectives

The objective of this post hoc analysis was to analyze real-world dual antiplatelet therapy (DAPT) regimens following polymer-free sirolimus-eluting stent (PF-SES) implantations in an unselected patient population.

Methods

Patient-level data from two all-comers observational studies (ClinicalTrials.gov Identifiers: NCT02629575 and NCT02905214) were pooled and analyzed in terms of their primary endpoint. During the data verification process, we observed substantial deviations from DAPT guideline recommendations. To illuminate this gap between clinical practice and guideline recommendations, we conducted a post hoc analysis of DAPT regimens and clinical event rates for which we defined the net adverse event rate (NACE) consisting of target lesion revascularization (TLR, primary endpoint of all-comers observational studies) all-cause death, myocardial infarction (MI), stent thrombosis (ST), and bleeding events. A logistic regression was utilized to determine predictors why ticagrelor was used in stable coronary artery disease (CAD) patients instead of the guideline-recommended clopidogrel.

Results

For stable CAD, the composite endpoint of clinical, bleeding, and stent thrombosis, i.e., NACE, between the clopidogrel and ticagrelor treatment groups was not different (5.4% vs. 5.1%, p = 0.745). Likewise, in the acute coronary syndrome (ACS) cohort, the NACE rates were not different between both DAPT strategies (9.2% vs. 9.3%, p = 0.927). There were also no differences in the accumulated rates for TLR, myocardial infarction ([MI], mortality, bleeding events, and stent thrombosis in elective and ACS patients. The main predictors for ticagrelor use in stable CAD patients were age < 65 years, smaller vessels, treatment of ostial and calcified lesions, and in-stent restenosis.

Conclusion

Within the framework of a post hoc analysis based on a real-world, large cohort study, there were no differences in the combined endpoint of major adverse cardiac events (MACE), bleeding and thrombotic events for clopidogrel and ticagrelor in stable CAD or ACS patients. Despite the recommendation for clopidogrel by the European Society of Cardiology (ESC), real-world ticagrelor use was observed in subgroups of stable CAD patients that ought to be explored in future trials.

Unrestricted use of polymer-free sirolimus eluting stents in routine clinical practice

Stent designs with ultrathin struts may further increase the procedural success of challenging lesion subsets. The objective of this study was to assess the safety and efficacy of ultrathin strut, polymer-free sirolimus eluting stent (PF-SES) implantations in a large scale, unselected patient population.Adult patients underwent percutaneous coronary interventions (PCI) with a thin-strut PF-SES. Data from two all-comers observational studies having the same protocol (ClinicalTrials.gov Identifiers: NCT02629575 and NCT02905214) were pooled. The accumulated target lesion revascularization (TLR) rate at 9-12 months was the primary endpoint. All dual antiplatelet therapy strategies according to the applicable guidelines were permissible.In total, 7243 patients were prospectively enrolled for PCI with PF-SES in stable coronary artery disease or acute coronary syndrome (ACS). Major risk factors in the overall cohort were diabetes (37.3%), ST elevation myocardial infarction (18.1%) and non-ST myocardial infarction (24.6%). The follow-up rate was 88.6% in the overall population. The TLR rate in the overall cohort was 2.2% whereas definite/probable stent thrombosis (ST) occurred in 0.7%. In patients with in-stent restenosis lesions, the major adverse cardiac events rate was 6.4% whereas the corresponding rate for isolated left main coronary artery (LMCA) disease was highest with 6.7% followed by patients with culprit lesions in vein bypasses (VB, 7.1%). The mortality rate in patients treated in VB lesions was highest with 5.4%, followed by the isolated LMCA subgroup (3.4%) and ACS (2.6%).PCI with PF-SES in an unselected patient population, is associated with low clinical event and ST rates. Furthermore, PF-SES angioplasty in niche indications demonstrated favorable safety and efficacy outcomes with high procedural success rates.

Polymer-free sirolimus-eluting stent use in Europe and Asia: Ethnic differences in demographics and clinical outcomes

BACKGROUND

The objective of this study was to assess regional and ethnic differences in an unselected patient population treated with polymer-free sirolimus-eluting stents (PF-SES) in Asia and Europe.

METHODS

Two all-comers observational studies based on the same protocol (ClinicalTrials.gov Identifiers: NCT02629575 and NCT02905214) were combined for data analysis to assure sufficient statistical power. The primary endpoint was the accumulated target lesion revascularization (TLR) rate at 9-12 months.

RESULTS

Of the total population of 7243 patients, 44.0% (3186) were recruited in the Mediterranean region and 32.0% (2317) in central Europe. The most prominent Asian region was South Korea (17.6%, 1274) followed by Malaysia (5.7%, 413). Major cardiovascular risk factors varied significantly across regions. The overall rates for accumulated TLR and MACE were low with 2.2% (140/6374) and 4.4% (279/6374), respectively. In ACS patients, there were no differences in terms of MACE, TLR, MI and accumulated mortality between the investigated regions. Moreover, dual antiplatelet therapy (DAPT) regimens were substantially longer in Asian countries even in patients with stable coronary artery disease as compared to those in Europe.

CONCLUSIONS

PF-SES angioplasty is associated with low clinical event rates in all regions. Further reductions in clinical event rates seem to be associated with longer DAPT regimens.

Efficacy and Safety of Polymer-Free Ultrathin Strut Sirolimus-Probucol Coated Drug-Eluting Stents for Chronic Total Occlusions: Insights from the Coroflex ISAR 2000 Worldwide Registry

Objective

Coronary revascularization in chronic total occlusion (CTO) is associated with improved clinical outcomes. The choice of the coronary stent is crucial in maintaining long-term vessel patency after CTO revascularization. We investigated the efficacy and safety of polymer-free ultrathin strut sirolimus-probucol coated drug-eluting stents (PF-SES) for CTO lesions.

Methods

Patients with CTO lesions treated with PF-SES were identified from the prospective multicenter international ISAR 2000 registry. The primary endpoint was clinically driven target lesion revascularization (TLR) at 9 months. Secondary endpoints were 9-month major adverse cardiac events (death, myocardial infarction, or TLR) (MACE) and the occurrence of stent thrombosis.

Results

A total of 111 patients with CTO lesions (n=127) were available for analysis. The 9-month clinical follow-up rate was 91%. The mean reference vessel diameter and lesion length were 2.76 mm ± 0.40 and 26.8 mm ± 13.1, respectively. The overall DAPT duration was 9.7 ± 2.8 months. Only one (1%) in-hospital MI was reported. The TLR and MACE rates at 9 months were 2% (2/101) and 5.9% (6/101), respectively. The 9-month accumulated rates of definite or probable stent thrombosis was 0% (0/101).

Conclusion

Revascularizations for CTO with PF-SES are associated with low rates of TLR and MACE at 9 months with no stent thrombosis. These initial findings need to be compared with results of other new generation DES of larger studies.

Nine-month clinical outcomes in patients with diabetes treated with polymer-free sirolimus-eluting stents and 6‑month vs. 12‑month dual-antiplatelet therapy (DAPT)

BACKGROUND

Diabetes mellitus is known to be associated with worse clinical outcomes in patients with coronary artery disease (CAD) undergoing percutaneous coronary interventions (PCI) with drug-eluting stents (DES). Defining the optimal duration of dual antiplatelet therapy (DAPT) after DES implantation is still under debate. The objective of this subgroup analysis of the all-comers ISAR 2000 registry was to assess the safety and efficacy of a short DAPT (<6 month) versus a longer DAPT (>6 month) in patients with diabetes electively treated with the polymer-free sirolimus-coated ultrathin strut drug-eluting stent (PF-SES).

METHODS

Patients who received the PF-SES were investigated in a multicenter all-comers observational study. The primary endpoint was the 9‑month target lesion revascularization (TLR) rate, whereas secondary endpoints included the 9‑month major adverse cardiac event (MACE) and procedural success rates.

RESULTS

In all, 167 patients were treated with DAPT for ≤6 months (S-DAPT group) and 350 patients underwent DAPT treatment for 12 months (L-DAPT group). There was no significant difference in the overall MACE rate (4.6% vs. 3.1%, p = 0.441), the 9‑month accumulated stent thrombosis rates (0.8% vs. 0.3%, p = 0.51), or the accumulated rate of bleeding complications (5.3% vs. 3.4%, p = 0.341).

CONCLUSION

PF-SES are safe and effective in daily clinical routine with low rates of TLR and MACE in patients with diabetes and stable disease. Our data suggest that extending the duration of DAPT beyond 6 months does not improve MACE or TLR at 9 months in patients with stable CAD (ClinicalTrials.gov Identifier NCT02629575).

Propensity score matched all comers population treated with ultra-thin strut bare metal and sirolimus-probucol coated drug-eluting stents of identical stent architecture

OBJECTIVE

The objective of this study was to compare the safety and efficacy of a polymer-free sirolimus coated, ultrathin strut drug eluting stent (PF-SES) to its uncoated bare-metal stent (BMS) platform of identical stent architecture.

BACKGROUND

Recently published randomized trials comparing BMS to DES with a focus on shortened dual-antiplatelet therapy reported incidences of stent thrombosis (ST) and bleeding complications (LEADERS FREE) in favor of drug eluting stents (DES).

METHODS

Data of previously published large-sale, international, single-armed, multicenter, observational studies of ultra-thin PF-SES, and BMS were propensity score (PS) matched for selected lesion morphological and cardiovascular risk factors to compare target lesion revascularization (TLR), myocardial infarction, cardiac death, major adverse cardiac events (MACE), bleeding complications and ST rates. Primary endpoint in both studies was TLR at 9 months.

RESULTS

At 9 months the rates of TLR was significantly lower in the PF-SES group as compared with patients treated with the BMS analogue of identical stent design (1.4% vs. 4.6%, P = 0.005). Likewise the 9-month MACE rates were lower in the PF-SES group (3.2% vs. 8.7%, P = 0.001) whereas there were no differences in the accumulated ST rates (0.5% vs. 1.5%, P = 0.109). Overall accumulated bleeding incidences (BARC 1-5) were not significantly different between PF-SES and BMS patients (1.8% vs. 2.7%, p = 0.388).

CONCLUSIONS

PF-SES are superior over analogue BMS of identical stent architecture in daily clinical routine with lower rates of TLR and MACE in a PS-matched, unselected patient population without differences in accumulated ST rates and bleeding frequencies given the currently favored postprocedural comedication (ClinicalTrials.gov Identifier NCT02629575).

Polymer-free sirolimus-eluting stents in a large-scale all-comers population

Objective

The objective of this study was to assess the safety and efficacy of a polymer-free sirolimus coated, ultrathin strut drug-eluting stent (PF-SES) in an unselected patient population with a focus on acute coronary syndrome (ACS). Furthermore, stable coronary artery disease (CAD) with short (≤6 months) versus long (>6 months) dual antiplatelet therapy (DAPT) were also studied.

Methods

Patients who received PF-SES were investigated in an unselected large-scale international, single-armed, multicenter, ‘all comers’ observational study. The primary endpoint was the 9-month target lesion revascularisation (TLR) rate, whereas secondary endpoints included the 9-month major adverse cardiac events (MACE) and procedural success rates. A priori defined subgroups such as patients with ACS, diabetes, lesion subsets and procedural characteristics relative to DAPT were investigated.

Results

A total of 2877 patients of whom 1084 had ACS were treated with PF-SES (1.31±0.75 stents per patient). At 9 months, the accumulated overall TLR rate was 2.3% (58/2513). There was no significant difference between ACS and stable CAD (2.6% vs 2.1%, p=0.389). However, the overall MACE rate was 4.3% (108/2513) with a higher rate in patients with ACS when compared with the stable CAD subgroup (6.1%, 58/947 vs 3.2%, 50/1566, p<0.001).

Conclusions

PF-SES angioplasty is safe and effective in the daily clinical routine with low rates of TLR and MACE in an unselected patient population. Our data are in agreement with prior clinical findings that extended DAPT duration beyond 6 months do not improve clinical outcomes in patients with stable CAD (ClinicalTrials.gov Identifier NCT02629575).

Trial registration number

NCT02629575.