Outcome of a polymer-free drug-coated coronary stent in bifurcation lesions-Pilot registry with serial OCT imaging

BACKGROUND

Polymer-free and carrier-free drug-coated stents (DCS) represent a novel therapeutic option for the treatment of coronary artery disease. The objective of this pilot registry is to evaluate the safety and efficacy of DCS implantation in bifurcation lesions.

METHODS

Overall, 23 consecutive patients with 24 lesions received a Biolimus A9-coated DCS for coronary bifurcation lesions. Patients were examined with quantitative coronary angiography (QCA) and optical coherence tomography (OCT) at 3-6 months of follow-up.

RESULTS

A total of 23 patients with 24 bifurcation lesions were included in this study. Nine (33.3%) lesions of eight patients revealed angiographical target lesion failure due to in-stent restenosis (ISR). In total, 19 patients with 20 bifurcation lesions were suitable for OCT analysis. A total of 2936 struts were analyzed and 14 struts (0.47%) were classified as malapposed. The mean luminal area (mm2) was not different in lesions with ISR vs. lesions with no ISR (5.07 ± 2.0 vs. 5.73 ± 1.34, p = 0.39) at follow-up. Lesions with ISR showed higher mean neointimal burden (27.11 ± 10.59 vs. 13.93 ± 9.16%, respectively; p = 0.009). All of the patients who presented with significant ISR required percutaneous re-intervention.

CONCLUSIONS

We observed a high rate of DCS ISR in bifurcation lesions, possibly related to increased inflammation and neoatherosclerosis. The small size of the study warrants careful interpretation of our results. Larger trials are necessary to expand knowledge of these findings.

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.

Machine learning-based prediction of adverse events following an acute coronary syndrome (PRAISE): a modelling study of pooled datasets

BACKGROUND

The accuracy of current prediction tools for ischaemic and bleeding events after an acute coronary syndrome (ACS) remains insufficient for individualised patient management strategies. We developed a machine learning-based risk stratification model to predict all-cause death, recurrent acute myocardial infarction, and major bleeding after ACS.

METHODS

Different machine learning models for the prediction of 1-year post-discharge all-cause death, myocardial infarction, and major bleeding (defined as Bleeding Academic Research Consortium type 3 or 5) were trained on a cohort of 19 826 adult patients with ACS (split into a training cohort [80%] and internal validation cohort [20%]) from the BleeMACS and RENAMI registries, which included patients across several continents. 25 clinical features routinely assessed at discharge were used to inform the models. The best-performing model for each study outcome (the PRAISE score) was tested in an external validation cohort of 3444 patients with ACS pooled from a randomised controlled trial and three prospective registries. Model performance was assessed according to a range of learning metrics including area under the receiver operating characteristic curve (AUC).

FINDINGS

The PRAISE score showed an AUC of 0·82 (95% CI 0·78-0·85) in the internal validation cohort and 0·92 (0·90-0·93) in the external validation cohort for 1-year all-cause death; an AUC of 0·74 (0·70-0·78) in the internal validation cohort and 0·81 (0·76-0·85) in the external validation cohort for 1-year myocardial infarction; and an AUC of 0·70 (0·66-0·75) in the internal validation cohort and 0·86 (0·82-0·89) in the external validation cohort for 1-year major bleeding.

INTERPRETATION

A machine learning-based approach for the identification of predictors of events after an ACS is feasible and effective. The PRAISE score showed accurate discriminative capabilities for the prediction of all-cause death, myocardial infarction, and major bleeding, and might be useful to guide clinical decision making.

FUNDING

None.

Real-world reasons and outcomes for 1-month versus longer dual antiplatelet therapy strategies with a polymer-free BIOLIMUS A9-coated stent

BACKGROUND

A large trial established the favorable profile of a new polymer-free biolimus A9-eluting stent (PF-BES) with a 1-month dual antiplatelet therapy (DAPT) in high bleeding risk (HBR) patients. This is the first study comparing outcomes for a 1-month versus longer DAPT strategies following PF-BES-percutaneous coronary intervention (PCI).

METHODS

All patients undergoing PF-BES-PCI (January 2016 to July 2018) were included in the multicenter CHANCE registry. Patients were stratified according to DAPT strategy at discharge (planned 1-month vs. planned >1-month). Primary outcomes were the 390-day estimates of a patient-oriented and of a device-oriented composite endpoints (POCE: death, myocardial infarction [MI] or target vessel revascularization; DOCE: cardiac death, target vessel-MI or ischemia-driven target lesion revascularization). Landmark analyses from 1-month post-PCI were carried.

RESULTS

Following PF-BES-PCI, 328(40.3%) and 485(59.6%) patients were discharged with 1-month and longer DAPT (12 months [6-12]), respectively. Patients with a previous or index MI were less likely to be discharged on 1-month DAPT. Patients prescribed with 1-month DAPT were more likely to be at HBR than those with longer DAPT (90.2% vs. 69.9%, p = .001). No between-groups differences in the primary outcomes (planned 1-month vs. planned >1-month DAPT: POCE 11.9% vs. 13.2%, p = .747; DOCE: 4.8% vs. 8.1%, p = .500) were observed, also after adjusting for confoundings (POCE: adjusted-hazard ratio [adj-HR] 1.26, 95%CI 0.74-2.13; DOCE: adj-HR 1.00, 95%CI 0.49-1.99). Landmark analyses showed similar results.

CONCLUSIONS

In a large all-comers registry of PF-BES PCI, no interaction of planned DAPT strategy (1-month vs. >1-month) with outcomes was found. This observation warrants investigation in adequately powered randomized studies (ClinicalTrials.gov NCT03622203).