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.

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).