Current Applications and New Perspectives in Optical Coherence Tomography (OCT) Coronary Atherosclerotic Plaque Assessment: From PCI Optimization to Pharmacological Treatment Guidance
Since its ability to precisely characterized atherosclerotic plaque phenotypes, to tailor stent implantation, as well as to guide both complex percutaneous coronary interventions (PCI) and invasive diagnostic work-ups (e.g., spontaneous coronary dissections or myocardial infarction with non-obstructive arteries), the adoption of optical coherence tomography (OCT) was raised in the past decades in order to provide complementary information to the traditional angiography and to overcome its limitations. However, the impact of OCT on daily clinical practice is currently modest, firstly because of the lack of both standardized algorithms of PCI guidance and data from prospective clinical trials. Therefore, the aim of our narrative review is to provide a comprehensive overview of the basic OCT interpretation, to summarize the evidence supporting the OCT guidance procedures and applications, to discuss its current limitations, and to highlight the knowledge gaps that need to be filled wit...
Early healing after treatment of coronary lesions by thin strut everolimus, or thicker strut biolimus eluting bioabsorbable polymer stents: The SORT-OUT VIII OCT study
Aims: Early healing after drug-eluting stent (DES) implantation may reduce the risk of stent thrombosis. The aim of this study was to compare patterns of early healing after implantation of the thin strut everolimus-eluting Synergy DES (Boston Scientific) or the biolimus-eluting Biomatix Neoflex DES (Biosensors).
Methods and results: A total of 160 patients with the chronic or acute coronary syndrome were randomized 1:1 to Synergy or Biomatrix DES. Optical coherence tomography (OCT) was performed at baseline and at either 1- or 3-month follow-up. The primary endpoint was a coronary stent healing index (CSHI), a weighted index of strut coverage, neointimal hyperplasia, malapposition, and extrastent lumen. A total of 133 cases had OCT follow-up and 119 qualified for matched OCT analysis. The median CSHI score did neither differ significantly between the groups at 1 month: Synergy 8.0 (interquartile range [IQR]: 3.0; 14.0) versus Biomatrix 8.5 (IQR: 4.0; 15.0) (p = 0.47) nor at 3 mo...
Efficacy of a new generation intracoronary optical coherence tomography imaging system with fast pullback
We sought to investigate whether a novel, fast-pullback, high-frequency optical coherence tomography (HF-OCT) imaging system enables data acquisition with a reduced amount of contrast agents while retaining the same qualitative and quantitative lesion assessment to conventional OCT.
The increased amount of administered contrast agents is a major concern when performing intracoronary OCT.
The present study is a single-center, prospective, observational study including 10 patients with stable coronary artery disease. A total of 28 individual coronary arteries were assessed by both fast-pullback HF-OCT and by conventional OCT.
The contrast volume used in each OCT run for the HF-OCT system was significantly lower than for the conventional OCT system (5.0 ± 0.0 mL vs. 7.8 ± 0.7 mL, respectively, with a mean difference of −2.84 [95% confidence interval [CI]: −3.10 to −2.58]). No significant difference was found in the median value of the clear ...
Assessment of fractional flow reserve in intermediate coronary stenosis using optical coherence tomography-based machine learning
Objectives: This study aimed to evaluate and compare the diagnostic accuracy of machine learning (ML)- fractional flow reserve (FFR) based on optical coherence tomography (OCT) with wire-based FFR irrespective of the coronary territory.
Background: ML techniques for assessing hemodynamics features including FFR in coronary artery disease have been developed based on various imaging modalities. However, there is no study using OCT-based ML models for all coronary artery territories.
Methods: OCT and FFR data were obtained for 356 individual coronary lesions in 130 patients. The training and testing groups were divided in a ratio of 4:1. The ML-FFR was derived for the testing group and compared with the wire-based FFR in terms of the diagnosis of ischemia (FFR ≤ 0.80).
Results: The mean age of the subjects was 62.6 years. The numbers of the left anterior descending, left circumflex, and right coronary arteries were 130 (36.5%), 110 (30.9%), and 116 (32.6%), respectively. Usin...
Management of Complex Pulmonary Vein Stenosis at Altitude Combining Comprehensive Percutaneous Interventional Treatment with Sirolimus, Pulmonary Hypertension Medications and Intraluminal Imaging with Optical Coherence Tomography
Pulmonary vein stenosis (PVS) is a growing problem for the pediatric congenital heart population. Sirolimus has previously been shown to improve survival and slow down the progression of in-stent stenosis in patients with PVS. We evaluated patients before and after initiation of sirolimus to evaluate its effects on re-intervention and vessel patency utilizing Optical Coherence Tomography (OCT).
We performed a retrospective study, reviewing the charts of patients with PVS, who had been prescribed sirolimus between October 2020 and December 2021. OCT was performed in the pulmonary vein of interest as per our published protocol. Angiographic and OCT imaging was retrospectively reviewed. Statistical analysis was performed using Chi square and Wilcoxon signed-rank test to compare pre-and post-sirolimus data.
Ten patients had been started and followed on sirolimus. Median age at sirolimus initiation was 25 months with median weight of 10.6 kg and averag...
Prevalence and patterns of in-stent neoatherosclerosis in lower extremity artery disease
Background: In-stent restenosis (ISR) is responsible for a rapid decline of vessel patency after stenting. To date, little is known about the role of in-stent neoatherosclerosis (NA) in stent failure in lower limb arteries.
Aims: This study aimed to determine the prevalence and patterns of in-stent NA in patients with symptomatic ISR of the lower extremity vasculature using intravascular optical coherence tomography (OCT) imaging.
Methods: Patients underwent endovascular revascularisation for ISR including angiography and OCT imaging. NA was defined as the presence of at least 1 fibroatheroma or fibrocalcific plaque within the neointima of a stented segment.
Results: Using OCT, we imaged 24 symptomatic patients with lower extremity artery disease (LEAD), with a total of 30 ISR in the lower limbs, prior to their scheduled endovascular interventions. NA formation was observed in 23 (76.7%) lesions, while all stents with an implant duration >5 years (n=8) showed signs of NA...
Pericoronary adipose tissue radiomics from coronary CT angiography identifies vulnerable plaques characteristics in intravascular OCT
Pericoronary adipose tissue (PCAT) features on CT have been shown to reflect local inflammation, and signals increased cardiovascular risk. Our goal was to determine if PCAT radiomics extracted from coronary CT angiography (CCTA) images are associated with intravascular optical coherence tomography (IVOCT)-identified vulnerable plaque characteristics (e.g., microchannels [MC] and thin-cap fibroatheroma [TCFA]). CCTA and IVOCT images of 30 lesions from 25 patients were registered. Vessels with vulnerable plaques were identified from the registered IVOCT images. PCAT radiomics features were extracted from CCTA images for the lesion region of interest (PCAT-LOI) and the entire vessel (PCAT-Vessel). We extracted 1356 radiomics features, including intensity (first-order), shape, and texture features. Features were reduced using standard approaches (e.g., high feature correlation). Using stratified three-fold cross-validation with 1000 repeats, we determined the ability of PCAT radiomics ...
Intravascular imaging-guided treatment of severe coronary artery calcification with orbital atherectomy: A prospective single-centre registry
Introduction: Coronary artery calcification can lead to suboptimal results when performing coronary angioplasty with conventional techniques. The presence of severe coronary artery calcium increases the complications of percutaneous coronary intervention as it may impede stent delivery and optimal stent expansion. The purpose of this study was to determine the procedural success and safety of orbital atherectomy (OA) in calcified lesions.
Materials and methods: This was a prospective single-centre study regarding the utility of OA in the treatment of calcified coronaries. Intravascular ultrasound (IVUS) or optical coherence tomography (OCT) was used in all cases to characterise the severity of calcium pre-procedure, guide vessel sizing and assess procedural success. The primary endpoint was procedural success, defined by successful stent implantation following OA treatment. The secondary endpoint was in-hospital and 30-day major adverse cardiovascular event (MACE).
Physiology-guided vs Angiography-guided Non-culprit Lesion Complete Revascularization for Acute MI & Multivessel Disease (COMPLETE-2)
COMPLETE-2 is a prospective, multi-centre, randomized controlled trial comparing a strategy of physiology-guided complete revascularization to angiography-guided complete revascularization in patients with acute ST-segment elevation myocardial infarction (STEMI) or non-ST-segment elevation myocardial infarction (NSTEMI) and multivessel coronary artery disease (CAD) who have undergone successful culprit lesion Percutaneous Coronary Intervention (PCI).
COMPLETE-2 OCT is a large scale, prospective, multi-centre, observational, imaging study of patients with STEMI or NSTEMI and multivessel CAD in a subset of eligible COMPLETE-2 patients.
Open-source, highly efficient, post-acquisition synchronization for 4D dual-contrast imaging of the mouse embryonic heart over development with optical coherence tomography
Dynamic imaging of the beating embryonic heart in 3D is critical for understanding cardiac development and defects. Optical coherence tomography (OCT) plays an important role in embryonic heart imaging with its unique imaging scale and label-free contrasts. In particular, 4D (3D + time) OCT imaging enabled biomechanical analysis of the developing heart in various animal models. While ultrafast OCT systems allow for direct volumetric imaging of the beating heart, the imaging speed remains limited, leading to an image quality inferior to that produced by post-acquisition synchronization. As OCT systems become increasingly available to a wide range of biomedical researchers, a more accessible 4D reconstruction method is required to enable the broader application of OCT in the dynamic, volumetric assessment of embryonic heartbeat. Here, we report an open-source, highly efficient, post-acquisition synchronization method for 4D cardiodynamic and hemodynamic imaging of the mouse embryonic ...
Optical coherence tomography characterization of spontaneous recanalized coronary thrombus – Single center experience
Introduction: Recanalized thrombus is an under diagnosed clinical entity. Aim was to investigate the utility of optical coherence tomography (OCT) in identifying spontaneously recanalized thrombi (SRCT) for management in clinical practice.
Methods: This was a retrospective study analyzing 2678 coronary angiograms over a 4-year period which included intravascular imaging guidance in 75.8% of the percutaneous coronary interventions (PCI). Angiographic suspicion of SRCT has hazy appearance seen in 34 patients.
Results: Eight patients (7 males and 1 female) were confirmed with SRCT on OCT and two underwent intravascular ultrasound (IVUS). Median age was 52 years (range 33-67 years). Based on clinical symptoms, diagnosis was STEMI-2, NSTEMI-1, unstable angina-3 and chronic stable angina-2. Angiographic patterns were veiled/hazy appearances in 3; braided in 2; pseudo dissection in 2; and near occlusion in 1 patient. OCT findings displayed multiple small cavities, signal-rich with hi...
Associations Between the Retinal/Choroidal Microvasculature and Carotid Plaque in Patients with CHD: An Optical Coherence Tomography Angiography Study
To investigate the associations between retinal/choroidal microvasculature and carotid plaque in patients with CHD assessed by optical coherence tomography angiography (OCTA).
This study included 127 CHD patients with and 79 without carotid plaque. Each patient had both OCTA taken and digitized to determine retinal/choroidal thickness, vessel density and flow area and carotid ultrasound for carotid plaque size and stability measurement. SCP, DCP, out retina and choriocapillaris vessel density, out retina and choriocapillaris flow area, and full retina thickness were analyzed in the fovea centered 6 × 6 mm area. The association between OCTA measurements and carotid plaque characteristics in patients with CHD were evaluated.
The duration of hypertension and DM was significantly longer in CHD patients with carotid plaque than that without (p < 0.001). The mean values for vessel density SCP and DCP (except fovea zone), and choriocapillaris na...
Determinants and long-term outcomes of largely uncovered struts in thin-struts drug-eluting stents assessed by optical coherence tomography
Uncovered struts are a determinant of stent failure. The impact of plaque composition and procedural factors on the occurrence, evolution, and outcomes of uncovered struts in a high-risk setting has not been investigated.
To investigate the determinants and long-term clinical impact of largely uncovered struts (LUS) in thin-struts drug-eluting stents (DES) implanted in complex lesions by intracoronary optical coherence tomography (OCT).
Ninety patients with multivessel disease undergoing staged complete revascularization were randomly assigned to bioabsorbable or durable polymer DES. OCT were serially performed during the index procedure, at 3- and 18-month follow-up, and analyzed by an independent core lab. Struts were defined uncovered by OCT if no tissue was visible above the struts. LUS were defined as ≥30% of uncovered struts at 3-month follow-up. Clinical outcomes were the occurrence of target vessel failure (TVF) and major adverse cardiac and...