Impact of Final Kissing Balloon and of Imaging on Patients Treated on Unprotected Left Main Coronary Artery With Thin-Strut Stents (From the RAIN-CARDIOGROUP VII Study)

Long-term impact of intravascular ultrasound-guidance for percutaneous coronary intervention on unprotected left main. The IMPACTUS-LM, an observational, multicentric study

INTRODUCTION

The potential benefit on long term outcomes of Percutaneous Coronary Intervention (PCI) on Unprotected Left Main (ULM) driven by IntraVascular UltraSound (IVUS) remains to be defined.

METHODS

IMPACTUS LM-PCI is an observational, multicenter study that enrolled consecutive patients with ULM disease undergoing coronary angioplasty in 13 European high-volume centers from January 2002 to December 2015. Major Adverse Cardiovascular Events (MACEs) a composite of cardiovascular (CV) death, target vessel revascularization (TVR) and myocardial infarction (MI) were the primary endpoints, while its single components along with all cause death the secondary ones.

RESULTS

627 patients with ULM disease were enrolled, 213 patients (34%) underwent IVUS-guided PCI while 414 (66%) angioguided PCI. Patients in the two cohorts had similar prevalence of risk factors except for active smoking and clinical presentation. During a median follow-up of 7.5 years, 47 (22%) patients in the IVUS group and 211 (51%) in the angio-guided group underwent the primary endpoint (HR 0.42; 95% CI [0.31-0.58] p < 0.001). After multivariate adjustment, IVUS was significantly associated with a reduced incidence of the primary endpoint (adj HR 0.39; 95% CI [0.23-0.64], p < 0.001), mainly driven by a reduction of TVR (ad HR 0.30, 95% CI [0.15-0.62], p = 0.001) and of all-cause death (adj HR 0.47, 95% CI [0.28-0.82], p = 0.008). IVUS use, age, diabetes, side branch stenosis, DES and creatinine at admission were independent predictors of MACE.

CONCLUSIONS

In patients undergoing ULM PCI, the use of IVUS was associated with a reduced risk at long-term follow-up of MACE, all-cause death and subsequent revascularization.

Role of Intracoronary Imaging in Myocardial Infarction with Non-Obstructive Coronary Disease (MINOCA): A Review

Myocardial infarction with non-obstructive coronary artery disease occurs in 6% to 15% of all presentation of myocardial infarctions. The pathophysiologic mechanisms of MINOCA include epicardial vasospasm, coronary microvascular disorder, spontaneous coronary artery dissection, and coronary thrombus/embolism. The diagnosis is challenging, supported by intracoronary imaging with intravascular ultrasound (IVUS) and optical coherent tomography (OCT), coronary physiology testing, and cardiac magnetic resonance imaging (CMR). OCT is able to identify atherosclerotic causes of MINOCA (plaque erosion, plaque rupture, and calcified nodule) and nonatherosclerotic causes (spontaneous artery dissection, and spasm). In this review, we summarize the performance of the two intracoronary imaging modalities (IVUS and OCT) in MINOCA and discuss the importance of supplementing these modalities with CMR in order to drive target therapy.

Ultrathin Struts Drug-Eluting Stents: A State-of-the-Art Review

New-generation drug-eluting stents (DESs) represent the standard of care for patients undergoing percutaneous coronary intervention (PCI). Recent iterations in DES technology have led to the development of newer stent platforms with a further reduction in strut thickness. This new DES class, known as ultrathin struts DESs, has struts thinner than 70 µm. The evidence base for these devices consists of observational data, large-scale meta-analyses, and randomized trials with long-term follow-up, which have been conducted to investigate the difference between ultrathin struts DESs and conventional new-generation DESs in a variety of clinical settings and lesion subsets. Ultrathin struts DESs may further improve the efficacy and safety profile of PCI by reducing the risk of target-lesion and target-vessel failures in comparison to new-generation DESs. In this article, we reviewed device characteristics and clinical data of the Orsiro (Biotronik, Bülach, Switzerland), Coroflex ISAR (B. Braun Melsungen, Germany), BioMime (Meril Life Sciences Pvt. Ltd., Gujarat, India), MiStent (MiCell Technologies, USA), and Supraflex (Sahajanand Medical Technologies, Surat, India) sirolimus-eluting stents.

Prediction of All-Cause Mortality Following Percutaneous Coronary Intervention in Bifurcation Lesions Using Machine Learning Algorithms

Stratifying prognosis following coronary bifurcation percutaneous coronary intervention (PCI) is an unmet clinical need that may be fulfilled through the adoption of machine learning (ML) algorithms to refine outcome predictions. We sought to develop an ML-based risk stratification model built on clinical, anatomical, and procedural features to predict all-cause mortality following contemporary bifurcation PCI. Multiple ML models to predict all-cause mortality were tested on a cohort of 2393 patients (training, n = 1795; internal validation, n = 598) undergoing bifurcation PCI with contemporary stents from the real-world RAIN registry. Twenty-five commonly available patient-/lesion-related features were selected to train ML models. The best model was validated in an external cohort of 1701 patients undergoing bifurcation PCI from the DUTCH PEERS and BIO-RESORT trial cohorts. At ROC curves, the AUC for the prediction of 2-year mortality was 0.79 (0.74–0.83) in the overall population, 0.74 (0.62–0.85) at internal validation and 0.71 (0.62–0.79) at external validation. Performance at risk ranking analysis, k-center cross-validation, and continual learning confirmed the generalizability of the models, also available as an online interface. The RAIN-ML prediction model represents the first tool combining clinical, anatomical, and procedural features to predict all-cause mortality among patients undergoing contemporary bifurcation PCI with reliable performance.

Impact of Left Ventricular Ejection Fraction on Procedural and Long-Term Outcomes of Bifurcation Percutaneous Coronary Intervention

The association of left ventricular ejection fraction (LVEF) with procedural and long-term outcomes after state-of-the-art percutaneous coronary intervention (PCI) of bifurcation lesions remains unsettled. A total of 5,333 patients who underwent contemporary coronary bifurcation PCI were included in the intercontinental retrospective combined insights from the unified RAIN (veRy thin stents for patients with left mAIn or bifurcatioN in real life) and COBIS (COronary BIfurcation Stenting) III bifurcation registries. Of 5,003 patients (93.8%) with known baseline LVEF, 244 (4.9%) had LVEF <40% (bifurcation with reduced ejection fraction [BIFrEF] group), 430 (8.6%) had LVEF 40% to 49% (bifurcation with mildly reduced ejection fraction [BIFmEF] group) and 4,329 (86.5%) had ejection fraction (EF) ≥50% (bifurcation with preserved ejection fraction [BIFpEF] group). The primary end point was the Kaplan-Meier estimate of major adverse cardiac events (MACEs) (a composite of all-cause death, myocardial infarction, and target vessel revascularization). Patients with BIFrEF had a more complex clinical profile and coronary anatomy. No difference in procedural (30 days) MACE was observed across EF categories, also after adjustment for in-study outcome predictors (BIFrEF vs BIFmEF: adjusted hazard ratio [adj-HR] 1.39, 95% confidence interval [CI] 0.37 to 5.21, p = 0.626; BIFrEF vs BIFpEF: adj-HR 1.11, 95% CI 0.25 to 2.87, p = 0.883; BIFmEF vs BIFpEF: adj-HR 0.81, 95% CI 0.29 to 2.27, p = 0.683). BIFrEF was independently associated with long-term MACE (median follow-up 21 months, interquartile range 10 to 21 months) than both BIFmEF (adj-HR 2.20, 95% CI 1.41 to 3.41, p <0.001) and BIFpEF (adj-HR 1.91, 95% CI 1.41 to 2.60, p <0.001) groups, although no difference was observed between BIFmEF and BIFpEF groups (adj-HR 0.87, 95% CI 0.61 to 1.24, p = 0.449). In conclusion, in patients who underwent PCI of a coronary bifurcation lesion according to contemporary clinical practice, reduced LVEF (<40%), although a strong predictor of long-term MACEs, does not affect procedural outcomes.

Benefit of Extended Dual Antiplatelet Therapy Duration in Acute Coronary Syndrome Patients Treated with Drug Eluting Stents for Coronary Bifurcation Lesions (from the BIFURCAT Registry)

Optimal dual antiplatelet therapy (DAPT) duration for patients undergoing percutaneous coronary intervention (PCI) for coronary bifurcations is an unmet issue. The BIFURCAT registry was obtained by merging two registries on coronary bifurcations. Three groups were compared in a two-by-two fashion: short-term DAPT (≤ 6 months), intermediate-term DAPT (6-12 months) and extended DAPT (>12 months). Major adverse cardiac events (MACE) (a composite of all-cause death, myocardial infarction (MI), target-lesion revascularization and stent thrombosis) were the primary endpoint. Single components of MACE were the secondary endpoints. Events were appraised according to the clinical presentation: chronic coronary syndrome (CCS) versus acute coronary syndrome (ACS). 5537 patients (3231 ACS, 2306 CCS) were included. After a median follow-up of 2.1 years (IQR 0.9-2.2), extended DAPT was associated with a lower incidence of MACE compared with intermediate-term DAPT (2.8% versus 3.4%, adjusted HR 0.23 [0.1-0.54], p <0.001), driven by a reduction of all-cause death in the ACS cohort. In the CCS cohort, an extended DAPT strategy was not associated with a reduced risk of MACE. In conclusion, among real-world patients receiving PCI for coronary bifurcation, an extended DAPT strategy was associated with a reduction of MACE in ACS but not in CCS patients.

Long-term (≥15 years) Follow-up of Percutaneous Coronary Intervention of Unprotected Left Main (From the GRAVITY Registry)

Long term survival and its determinants after Percutaneous Coronary Intervention (PCI) on Unprotected Left Main Coronary Artery (ULMCA) remain to be appraised. In 9 European Centers 470 consecutive patients performing PCI on ULMCA between 2002 and 2005 were retrospectively enrolled. Survival from all cause and cardiovascular (CV) death were the primary end points, while their predictors at multivariate analysis the secondary ones. Among the overall cohort 81.5% of patients were male and mean age was 66 ± 12 years. After 15 years (IQR 13 to 16), 223 patients (47%) died, 81 (17.2%) due to CV etiology. At multivariable analysis, older age (HR 1.06, 95%CI 1.02 to 1.11), LVEF < 35% (HR 2.97, 95%CI 1.24 to 7.15) and number of vessels treated during the index PCI (HR 1.75, 95%CI 1.12 to 2.72) were related to all-cause mortality, while only LVEF <35% (HR 4.71, 95%CI 1.90 to 11.66) to CV death. Repeated PCI on ULMCA occurred in 91 (28%) patients during the course of follow up and did not significantly impact on freedom from all-cause or CV mortality. In conclusion, in a large, unselected population treated with PCI on ULMCA, 47% died after 15 years, 17% due to CV causes. Age, number of vessels treated during index PCI and depressed LVEF increased risk of all cause death, while re-PCI on ULMCA did not impact survival.

Percutaneous vs. surgical revascularization for patients with unprotected left main stenosis: a meta-analysis of 5-year follow-up randomized controlled trials

AIMS

A 5-year survival of patients with unprotected left main (ULM) stenosis according to the choice of revascularization (percutaneous vs. surgical) remains to be defined.

METHODS AND RESULTS

Randomized controlled trials (RCTs) comparing percutaneous coronary intervention (PCI) vs. coronary artery bypass graft (CABG) with a follow-up of at least 5 years were included. All-cause death was the primary endpoint. MACCE [a composite endpoint of all-cause mortality, myocardial infarction (MI), stroke, and repeat revascularization] along with its single components and cardiovascular (CV) death were the secondary ones. Analyses were stratified according to the use of first- vs. last-generation coronary stents. Subgroup comparisons were performed according to SYNTAX score (below or above 33) and to age (using cut-offs of each trial's subgroup analysis). Four RCTs with 4394 patients were identified: 2197 were treated with CABG, 657 with first generation, and 1540 with last-generation stents. At 5-year rates of all-cause death did not differ [odds ratio (OR) 0.93, 95% confidence interval (CI) 0.71-1.21], as those of CV death and stroke. Coronary artery bypass graft reduced rates of MACCE (OR 0.69, 95% CI 0.60-0.79), mainly driven by MI (OR 0.48, 95% CI 0.36-0.65) and revascularization (OR 0.53, 95% CI 0.45-0.64). Benefit of CABG for MACCE was consistent, although with different extent, across values of SYNTAX score (OR 0.76, 95% CI 0.59-0.97 for values < 32 and OR 0.63, 95% CI 0.47-0.84 for values ≥ 33) while was not evident for 'younger' patients (OR 0.83, 95% CI 0.65-1.07 vs. OR 0.65, 95% CI 0.51-0.84 for 'older' patients).

CONCLUSION

For patients with ULM disease followed-up for 5 years, no significant difference was observed in all-cause and cardiovascular death between PCI and CABG. Coronary artery bypass graft reduced risk of MI, revascularization, and MACCE especially in older patients and in those with complex coronary disease and a high SYNTAX score.

Percutaneous coronary intervention versus coronary artery surgery for left main disease according to lesion site: A meta-analysis

BACKGROUND

Comparative data after percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) for unprotected left main coronary artery (ULMCA) disease according to lesion site (ostial/shaft vs distal) are scant. The aim of this meta-analysis was to investigate outcomes after PCI or CABG for ULMCA disease according to lesion site.

METHODS

Randomized controlled trials (RCTs) and adjusted observational studies that compared PCI versus CABG in patients with ULMCA disease and reported outcomes according to lesion site were systematically identified. Major adverse cardiovascular events (MACE; a composite of all-cause death, myocardial infarction, stroke, and repeat revascularization) and all-cause death were the co-primary end points. Individual components of MACE were secondary end points. Sensitivity analysis including RCTs only were performed for each outcome.

RESULTS

Nine studies (3 RCTs, 6 adjusted observational), encompassing 6296 patients (2274 and 4022 treated for ostial/shaft or distal ULMCA, respectively) were included. At the 5-year follow-up, there were no significant differences between CABG and PCI for MACE, death, or any other secondary outcome for ostial/shaft ULMCA lesions (MACE: hazard ratio [HR], 1.0 [95% confidence interval (CI), 0.79-1.27]; death: HR, 1.10 [95% CI, 0.84-1.46]). For distal ULMCA, PCI was associated with an increased risk of MACE (HR, 1.32; 95% CI, 1.10-1.58), death (HR, 1.56; 95% CI, 1.19-2.04), and revascularization (HR, 2.07; 95% CI, 1.5-2.84). The benefit of CABG for MACE and revascularization was confirmed in the analysis limited to RCTs, whereas the benefit for mortality was not.

CONCLUSIONS

Among patients with distal ULMCA disease, CABG is associated with lower incidence of MACE and revascularization compared with PCI, whereas no differences in outcomes were observed for ostial/shaft ULMCA disease.

Impact of stent thickness on clinical outcomes in small vessel and bifurcation lesions: a RAIN-CARDIOGROUP VII sub-study

BACKGROUND

The clinical impact of stent strut thickness in coronary bifurcation lesions in small vessels has not been assessed in a real-world population.

METHODS

All 506 patients enrolled in the RAIN study, undergoing PCI in a vessel with a diameter 2.5 mm or less were retrospectively evaluated and divided into two groups according to stent strut thickness: 74 μm (n = 206) versus 81 μm (n = 300); 87.1% of the lesions involved bifurcations. TLF [defined as a composite of myocardial infarction (MI) and target lesion revascularization (TLR)] was the primary endpoint, with MACE (a composite of death, MI and TLR), its components and stent thrombosis the secondary endpoint.

RESULTS

After 16 (14-18) months, a lower incidence of TLF (4.3 vs. 9.8%, P = 0.026) and ST (1.0 vs. 3.0%, P = 0.042) was seen in the 74 μm group, whereas MACE occurred in 60 of 506 patients, with no statistical difference between the two groups (9.7 vs. 13.3%, P = 0.070). At multivariate analysis, chronic renal failure increased the risk of TLF while thinner strut was an independent protective factor (hazard ratio 0.51, CI 0.17-0.85, P = 0.005).

CONCLUSION

In this real-world population, patients being treated for small vessels lesions with thinner strut stents had lower rates of TLF, MI and ST.

Polymer-free biolimus-eluting stents or polymer-based zotarolimus-eluting stents for coronary bifurcation lesions

BACKGROUND

A polymer-free biolimus-eluting stent (PF-BES) and a zotarolimus-eluting stent (ZES) recently showed similar clinical profiles and appear to be competing options in specific clinical settings of patients undergoing percutaneous coronary intervention (PCI). Whether they perform similarly also in complex procedural settings as coronary bifurcation lesions remains unaddressed.

METHODS

All consecutive patients undergoing coronary bifurcation PCI with PF-BES or the new iteration of the ZES from three large multicenter real-world registries were included. The primary outcome was major adverse cardiovascular events (MACE), a composite of all-cause death, myocardial infarction (MI), target lesion revascularization (TLR) and stent thrombosis (ST). Multiple analyses to adjust for baseline differences were carried out including propensity-score matching, propensity-score stratification and inverse-probability-weighting. Outcomes are reported according to Cox proportional hazard models censored at 400-day follow-up.

RESULTS

1169 patients treated with PF-BES (n = 440) or ZES (n = 729) on the main branch of a coronary bifurcation lesion were included (mean age 69 ± 11 years, 75.4% male, 53.8% acute coronary syndrome at presentation, 26.6% left main bifurcation, median dual antiplatelet therapy duration 12 [range 12-12] months). MACE, all-cause death, TLR and ST tended towards non-statistically higher rates with the PF-BES as compared to the ZES. Higher MI and target vessel revascularization occurrence was observed with PF-BES.

CONCLUSIONS

In this large contemporary cohort of patients undergoing coronary bifurcation PCI, the occurrence of MACE was non-statistically different with the use of PF-BES and ZES devices. However, differences favoring the ZES device that may entail clinical relevance were observed. Further studies are needed to confirm these findings and explore whether they remain valid when a short dual antiplatelet therapy is adopted.

Accuracy of the PARIS score and PCI complexity to predict ischemic events in patients treated with very thin stents in unprotected left main or coronary bifurcations

BACKGROUND

The PARIS risk score (PARIS-rs) and percutaneous coronary intervention complexity (PCI-c) predict clinical and procedural residual ischemic risk following PCI. Their accuracy in patients undergoing unprotected left main (ULM) or bifurcation PCI has not been assessed.

METHODS

The predictive performances of the PARIS-rs (categorized as low, intermediate, and high) and PCI-c (according to guideline-endorsed criteria) were evaluated in 3,002 patients undergoing ULM/bifurcation PCI with very thin strut stents.

RESULTS

After 16 (12-22) months, increasing PARIS-rs (8.8% vs. 14.1% vs. 27.4%, p < .001) and PCI-c (15.2% vs. 11%, p = .025) were associated with higher rates of major adverse cardiac events ([MACE], a composite of death, myocardial infarction [MI], and target vessel revascularization), driven by MI/death for PARIS-rs and target lesion revascularization/stent thrombosis for PCI-c (area under the curves for MACE: PARIS-rs 0.60 vs. PCI-c 0.52, p-for-difference < .001). PCI-c accuracy for MACE was higher in low-clinical-risk patients; while PARIS-rs was more accurate in low-procedural-risk patients. ≥12-month dual antiplatelet therapy (DAPT) was associated with a lower MACE rate in high PARIS-rs patients, (adjusted-hazard ratio 0.42 [95% CI: 0.22-0.83], p = .012), with no benefit in low to intermediate PARIS-rs patients. No incremental benefit with longer DAPT was observed in complex PCI.

CONCLUSIONS

In the setting of ULM/bifurcation PCI, the residual ischemic risk is better predicted by a clinical risk estimator than by PCI complexity, which rather appears to reflect stent/procedure-related events. Careful procedural risk estimation is warranted in patients at low clinical risk, where PCI complexity may substantially contribute to the overall residual ischemic risk.

Occurence of left main occlusion on Tuesday: Chronobiology of acute myocardial infarction due to left main disease

Objectives

The existence of a “weekend effect” for onset of acute myocardial infarction (AMI) has been suggested in the past, but the relation with the culprit vessel has not been investigated. MI due to left main coronary artery lesion represents a particularly serious life-threatening condition. Our study was aimed to assess the chronobiology of admission to the emergency department for AMI considered to be induced by a left main culprit lesion.

Methods

We retrospectively reviewed patients who experienced an AMI due to a left main culprit lesion between January 1, 2008 and January 1, 2018 stratifying them according to the day of admission, on the basis of the symptom onset time; the 30-day cardiovascular mortality was also analyzed on the basis of the time of symptom onset.

Results

Out of 1789 patients with AMI, 130 (7.2%, 104 males and 26 females, mean age 74.5 ± 8.1 years) had left main disease as the culprit lesion. Tuesday was significantly over-represented as the admission day (p < 0.001 for Tuesday vs. other days; p = 0.009 for Tuesday vs. Sunday, respectively). The 30-day cardiovascular survival was not different between patients admitted on Tuesday and those admitted on remaining days (Log-rank, Mantel Cox, p = 0.43; Chi-square = 0.611). A significant difference was noted in patients with AMI on Sunday versus remaining days (Log-rank, Mantel-Cox, p = 0.005; Chi-square = 7.96). The diameter of the left main artery was larger in patients admitted on Tuesdays than on Sundays (p < 0.01).

Conclusion

The relation between AMI onset and the day of the week is confirmed by our study, which also suggests that in case of a left main lesion, some delay of the weekend effect might be expected.

Impact of Kissing Balloon in Patients Treated With Ultrathin Stents for Left Main Lesions and Bifurcations

Background:

There are limited data regarding the impact of final kissing balloon (FKI) in patients treated with percutaneous coronary intervention using ultrathin stents in left main or bifurcations.

Methods:

All patients undergoing left main or bifurcations percutaneous coronary intervention enrolled in the RAIN registry (Very Thin Stents for Patients With MAIN or BiF in Real Life: The RAIN, a Multicenter Study) evaluating ultrathin stents were included. Major adverse cardiac event (a composite of all-cause death, myocardial infarction, target lesion revascularization, and stent thrombosis) was the primary end point, while its components, along with target vessel revascularization, were the secondary end points. The main analysis was performed comparing patients with and without FKI after adjustment with inverse probability of treatment weighting. Subgroup analyses were performed according to FKI (short [<3 mm] versus long overlap), strategy (provisional versus 2-stent), routine versus bail-out FKI, and the use of imaging and proximal optimization technique.

Results:

Two thousand seven hundred forty-two patients were included. At 16 months (8–20) follow-up, inverse probability of treatment weighting adjusted rates of major adverse cardiac event were similar between FKI and no-FKI group (15.1% versus 15.5%; P =0.967), this result did not change with use of imaging, proximal optimization technique, or routine versus bail-out FKI. In the 2-stent subgroup, FKI was associated with lower rates of target vessel revascularization (7.8% versus 15.9%; P =0.030) and target lesion revascularization (7.3% versus 15.2%; P =0.032). Short overlap FKI was associated with a lower rate of target lesion revascularization compared with no FKI (2.6% versus 5.4%; P =0.034), while long overlap was not (6.8% versus 5.4%; P =0.567).

Conclusions:

In patients with bifurcations or unprotected left main treated with ultrathin stents, short overlap FKI is associated with less restenosis. In a 2-stent strategy, FKI was associated with less target vessel revascularization and restenosis.

Registration:

URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03544294.

Percutaneous Coronary Intervention for Coronary Bifurcation Lesions: Latest Evidence

PURPOSE OF REVIEW

This paper provides a synopsis of the best evidence to guide bifurcation percutaneous coronary intervention (PCI), with a focus on recent studies. This is with the aim of guiding the interventional cardiologist in choosing the best, evidence-based technique, to treat commonly encountered coronary bifurcations.

RECENT FINDINGS

Current evidence supports the use of provisional stenting for most anatomically suitable bifurcation lesions. Newer techniques for side branch protection in provisional stenting have been developed. When a two-stent strategy is required, use of a double-kissing crush technique is favoured, particularly in left main bifurcations. For bifurcation PCI, as in all complex procedures, intravascular imaging plays a key adjunctive role in improving procedural success. PCI for coronary bifurcation lesions is an ever-growing field with significant advancements in techniques and technology.

Impact of structural features of very thin stents implanted in unprotected left main or coronary bifurcations on clinical outcomes

OBJECTIVES

To evaluate the independent clinical impact of stent structural features in a large cohort of patients undergoing unprotected left main (ULM) or coronary bifurcation percutaneous coronary intervention (PCI) with a range of very thin strut stents.

BACKGROUND

Clinical impact of structural features of contemporary stents remains to be defined.

METHODS

All consecutive patients enrolled in the veRy thin stents for patients with left mAIn or bifurcatioN in real life (RAIN) registry were included. The following stent structural features were studied: antiproliferative drugs (everolimus vs. sirolimus vs. zotarolimus), strut material (platinum-chromium vs. cobalt-chromium), polymer (bioresorbable vs. durable), number of crowns (<8 vs. ≥8) and number of connectors (<3 vs. ≥3). For small diameter stents (≤2.5 mm), struct thickness (74 vs. 80/81 μm) was also tested. Target lesion failure (TLF), a composite of target lesion revascularization and stent thrombosis, was the primary endpoint. Multivariate analysis was performed with Cox regression models.

RESULTS

Out of 2,707 patients, 110 (4.1%) experienced a TLF event after 16 months (12-18). After adjustment for confounders, an increased number of connectors (adjusted hazard ratio [adj-HR] 0.62, 95% confidence interval (CI) 0.39-0.99, p = .04) reduced risk of TLF, driven by stents with ≥2.5 mm diameter (HR 0.54, 95% CI 0.32-0.93, p = .02). This independent relationship was lost for stents with diameter <2.5 mm, where only strut thickness appeared to impact. Conversely, no independent relationship of polymer type, number of crowns, and the specific limus-family eluted drug with outcomes was observed.

CONCLUSIONS

Among a range of contemporary very thin stent models, an increased number of connectors improved device-related outcomes in this investigated high-risk procedural setting.

Comparative Effectiveness and Safety of Polymer-Free Biolimus-Eluting Stent and Durable Polymer Everolimus-Eluting Stent in All-Comer Patients Who Underwent Percutaneous Coronary Interventions

We aim to compare Polymer-Free Biolimus-Eluting Stent (PF-BES) with Durable Polymer Everolimus-Eluting stent (DP-EES) in unselected patients. PF-BES showed a favorable profile in high-bleeding risk patients who underwent percutaneous coronary intervention. Limited data are available on PF-BES compared with second-generation durable polymer-coated drug-eluting stents in patients eligible for standard dual antiplatelet therapy. A total of 848 consecutive patients were enrolled: 306 patients were treated with PF-BES and 542 with DP-EES. Stent performance was tested in a propensity score-matched population and in a Complex Higher-Risk and Indicated Patients (CHIP) subpopulation. A per-lesion analysis on 1,204 lesions (PF-BES = 424 vs DP-EES = 780) was also performed. At a medium follow-up of 18.5 ± 5.0 months, no differences in the matched population were found in terms of major adverse cardiac events (PF-BES 9.0% vs DP-EES 4.5%; p 0.091), myocardial infarction (PF-BES 6.2% vs DP-EES 2.3%; p 0.111), stent restenosis (PF-BES 2.3% vs DP-EES 0.0%; p 0.123), definite or probable stent thrombosis (PF-BES 2.8% vs DP-EES 1.1%; p 0.448). A significant inferior rate of restenosis was observed in the DP-EES arm in the whole (PF-BES 2.3% vs DP-EES 0.6%; p 0.041) and CHIP populations (PF-BES 4.3% vs DP-EES 0.5%; p 0.023), as well as in the per-lesion analysis (DP-EES 0.4% vs PF-BES 1.7%; p 0.039). In conclusion, in a real-world cohort PF-BES performed similarly to DP-EES in terms of restenosis and stent thrombosis in the matched population. Nonetheless, in the whole and CHIP populations, as well as in the per-lesion analysis, restenosis occurrence resulted higher in the PF-BES group.