Impact of Culprit Plaque and Atherothrombotic Components on Incomplete Stent Apposition in Patients With ST-Elevation Myocardial Infarction Treated With Everolimus-Eluting Stents – An OCTAVIA Substudy –

Lipid Content Distribution and its Clinical Implication in Patients with Acute Myocardial Infarction-Plaque Erosion: Results from the Prospective OCTAMI Study

AIMS

Plaque erosion (PE) is one of the main plaque phenotypes of acute coronary syndrome (ACS). However, the underlying plaque component and distribution have not been systematically analysed. This study aims to investigate the distribution of lipid and calcium content in culprit lesions assessed by optical coherence tomography (OCT) in patients with PE and explore its relationship with prognosis in a cohort of ST segment elevation myocardial infarction (STEMI) patients.

METHODS

A prospective cohort of 576 patients with STEMI was enrolled in our study. After exclusion, 152 PE patients with clear underlying plaque components were ultimately analysed. The culprit lesion was divided into the border zone, external erosion zone and erosion site in the longitudinal view. Each pullback of the culprit lesions was assessed by 3 independent investigators frame-by-frame, and the quantity and distribution of lipid and calcium components were recorded.

RESULTS

Of the 152 PE patients, lipid and calcium contents were more likely to exist in the external erosion zone than in the other regions. In particular, a high level of lipid content proximal to the erosion site was significantly associated with plaque vulnerability and a higher incidence of MACEs.

CONCLUSION

This study revealed that high level of lipid content in the proximal external erosion zone was related to high-risk plaque characteristics and poor prognosis, which provided a novel method for risk stratification and precise management in patients with plaque erosion.

Using Optical Coherence Tomography to Identify Lipid and Its Impact on Interventions and Clinical Events - A Scoping Review

BACKGROUND

Optical coherence tomographic (OCT) imaging has enabled identification of lipid, with increasing interest in how it may affect coronary interventions and clinical outcomes. This review summarizes the available evidence around OCT identification of lipid and its effect on interventions, clinical events, and the natural history of coronary disease.Methods and Results:We conducted a scoping review using the Medline, HealthStar, and Embase databases for articles published between 1996 and 2021. We screened 1,194 articles and identified 51 for inclusion in this study, summarizing the key findings. The literature supports a common OCT definition of lipid as low-signal regions with diffuse borders, validated against histology and other imaging modalities with acceptable intra- and inter-rater reliability. There is evidence that OCT-identified lipid at the site of stent implantation increases the risk of edge dissection, incomplete stent apposition, in-stent tissue protrusion, decreased coronary flow after stenting, side branch occlusion, and post-procedural cardiac biomarker increases. In mostly retrospective studies, lipid indices measured at non-stented sites are associated with plaque progression and the development of recurrent ischemic events.

CONCLUSIONS

There is extensive literature supporting the ability of OCT to identify lipid and demonstrating a substantial impact of lipid on percutaneous coronary intervention outcomes. Future work to prospectively evaluate the effect of the characteristics of lipid-rich plaques on long-term clinical outcomes is needed.

Long-term Clinical Outcomes of Drug-Eluting Stent Malapposition

Previous pathologic, intravascular imaging, and clinical studies have investigated the association between adverse cardiac events and stent malapposition, including acute stent malapposition (ASM, that is detected at index procedure) and late stent malapposition (LSM, that is detected during follow-up) that can be further classified into late-persistent stent malapposition (LPSM, ASM that remains at follow-up) or late-acquired stent malapposition (LASM, newly developed stent malapposition at follow-up that was not present immediately after index stent implantation). ASM has not been associated with adverse cardiac events compared with non-ASM, even in lesions with large-sized malapposition. The clinical outcomes of LSM may depend on its subtype. The recent intravascular ultrasound studies with long-term follow-up have consistently demonstrated that LASM steadily increased the risk of thrombotic events in patients with first-generation drug-eluting stents (DESs). This association has not yet been identified in LPSM. Accordingly, it is reasonable that approaches to stent malapposition should be based on its relationship with clinical outcomes. ASM may be tolerable after successful stent implantation, whereas prolonged anti-thrombotic medications and/or percutaneous interventions to modify LASM may be considered in selected patients with first-generation DESs. However, these treatments are still questionable due to lack of firm evidences.

Impact of an optical coherence tomography guided approach in acute coronary syndromes: A propensity matched analysis from the international FORMIDABLE-CARDIOGROUP IV and USZ registry

AIM

To determine the potential clinical impact of OCT (Optical Coherence Tomography) during primary percutaneous coronary intervention in patients presenting with ACS (Acute Coronary Syndrome).

METHODS AND RESULTS

FORMIDABLE is a multicentre retrospective registry enrolling all patients presenting with ACS and treated with an OCT-guided approach, while the USZ registry enrolled patients treated with a standard angiography guided approach. Multivariate adjustment was performed via a propensity score matching. The number stents useds was the primary outcome, while the incidence of MACE (a composite of death, myocardial infarction, target vessel revascularization, and stent thrombosis) was the secondary endpoint. A total of 285 patients OCT-guided and 1,547 angiography guided patients were enrolled, resulting in 270 for each cohort after propensity score with matching. Two stents were used in 12% versus 34%; 3 stents in 8% versus 38% of the patients (P < 0.001). After a follow up of 700 days (450-890), there was no difference in myocardial infarction (6% vs. 6%, P = 0.86), while MACE (11% vs. 16%, P = 0.06), target vessel revascularization (2% vs. 4%, P = 0.15) and stent thrombosis rates (0% vs. 2.7%, P = 0.26) were numerically lower for the OCT-guided cohort but none of these endpoints did reach statistical significance.

CONCLUSIONS

An OCT-guided approach reduced the number of stents used, number of patients treated with more than one stent, while there was no statistically significant difference in clinical endpoints while most of them were numerically lower, including stent thrombosis rates. © 2016 Wiley Periodicals, Inc.