Implicancias de la inteligencia artificial en los métodos de imagen endovascular / Implications of Artificial Intelligence in Intravascular Imaging Methods

RESUMEN La angioplastia transluminal coronaria (ATC) es una de las principales estrategias de revascularización en pacientes con enfermedad coronaria aterosclerótica (ECA). Numerosos estudios respaldan la optimización de la ATC mediante métodos de imagen endovascular; sin embargo, estos métodos son subutilizados en la práctica clínica contemporánea y enfrentan desafíos en la interpretación de los datos obtenidos, por lo que la integración de la inteligencia artificial (IA) se vislumbra como una solución atractiva para promover y simplificar su uso. La IA se define como un programa computarizado que imita la capacidad del cerebro humano para recopilar y procesar datos. El aprendizaje de máquinas es una subdisciplina de la IA que implica la creación de algoritmos capaces de analizar grandes conjuntos de datos sin suposiciones previas, mientras que el aprendizaje profundo se centra en la construcción y entrenamiento de redes neuronales artificiales profundas y complejas. Así, se ha demostrado que la incorporación de sistemas de IA a los métodos de imagen endovascular incrementa la precisión de la ATC, disminuye el tiempo del procedimiento y la variabilidad interobservador en la interpretación de los datos obtenidos, promueve así una mayor adopción y facilita su utilización. El propósito de la presente revisión es destacar cómo los sistemas actuales basados en IA pueden desempeñar un papel fundamental en la interpretación de los datos generados por los métodos de imagen endovascular, lo que conduce a una mejora en la optimización de la ATC en pacientes con ECA.

ABSTRACT Percutaneous coronary intervention (PCI) is one of the primary revascularization strategies in patients with coronary artery disease (CAD). Several studies support the use of intravascular imaging methods to optimize PCI. However, these methods are underutilized in contemporary clinical practice and face challenges in data interpretation. Therefore, the incorporation of artificial intelligence (AI) is seen as an attractive solution to promote and simplify their use. AI can be defined as a computer program that mimics the human brain in its ability to collect and process data. Machine learning is a sub-discipline of AI that involves the creation of algorithms capable of analyzing large datasets without making prior assumptions, while deep learning focuses on the construction and training of deep and complex artificial neural networks. The incorporation of AI systems to intravascular imaging methods improves the accuracy of PCI, reduces procedure duration, and minimizes interobserver variability in data interpretation. This promotes their wider adoption and facilitates their use. The aim of this review is to highlight how current AI-based systems can play a key role in the interpretation of data generated by intravascular imaging methods and optimize PCI in patients with CAD.

2023 clinical research inventory in the field of coronary heart disease / 中国介入心脏病学杂志

This review summarizes the progress of significant clinical studies in the field of coronary heart disease in 2023.The authors search from top-class medical journals on the Web of Science website,using'heart''cardi*''myocardi*''coronary''arrhythmi*''valv*''hypertension'as keywords.Various original researches that are highly quoted and have much value for clinical guidance are finally screened out,mainly focusing on intravascular imaging,strategy of percutaneous coronary revascularization,in-stent restenosis,antiplatelet therapy,and lipid management.From optimizing technologies of diagnosis and treatment to developing new types of drugs,we hope the achievements could effectively reduce the global burden of coronary heart disease.

A study of the safety and efficacy of intravascular lithotripsy in the treatment of coronary artery calcification lesions / 中国介入心脏病学杂志

Objective To evaluate the safety and efficacy of intravascular lithotripsy(IVL)in the treatment of coronary artery calcification lesions.Methods A total of 53 patients who underwent endovascular imaging guided treatment of coronary artery calcified lesions with either IVL or cutting balloon(CB)at the Affiliated Hospital of Jining Medical College from January 2023 to July 2023 were retrospectively analysed(IVL:n=18,CB:n=35)were retrospectively analysed to compare the technique,clinical success rate,major adverse cardiovascular events(MACE)and readmission for cardiovascular events in patients followed during hospitalisation and 1 month after the procedure.Results Clinical success rates were identical in the IVL and CB groups(100.0％vs.100.0％,P＞0.999),the minimum lumen area of lesions was similar in the VL and CB groups[(1.7±0.4)mm2 vs.(1.7±0.5 mm2),P=0.628].And there was a statistically significant difference in the overall mean lesion length between the IVL and CB groups[(28.4±9.6)mm vs.(20.9±8.6)mm,P=0.008].During the procedure,there were no complications such as aneurysm,thrombus,or emergency vessel closure.There was a statistically significant difference in the overall mean value of residual stenosis between the IVL and CB groups[(1.7±1.7)％vs.(6.9±2.0)％,P=0.049].There were no MACE in either group during hospitalisation or at the one-month follow-up(0 vs.0,P＞0.999),and 3 patients in the CB group were readmitted for angina pectoris(0 vs.8.6％,P=0.543),with no significant difference in readmission rates between the two groups.Conclusions The technique of intravascular lithotripsy is safe and effective in the treatment of coronary artery calcification lesions.

Multimodal intravascular photoacoustic and ultrasound imaging

The rupture of atherosclerotic plaques is the leading cause of death in developed countries. Early identification of vulnerable plaque is the essential step in preventing acute coronary events. Intravascular photoacoustic (IVPA) technology is able to visualize chemical composition of atherosclerotic plaque with high specificity and sensitivity. Integrated with intravascular ultrasound (IVUS) imaging, this multimodal intravascular IVPA/IVUS imaging technology is able to provide both structural and chemical compositions of arterial walls for detecting and characterizing atherosclerotic plaques. In this paper, we present representative multimodal IVPA/IVUS imaging systems and discuss current scientific innovations, potential limitations, and prospective improvements for characterization of coronary atherosclerosis.

Tomografía de coherencia óptica: Bases y aplicaciones de una nueva técnica de imagen intravascular

La angiografía es la técnica de referencia para el diagnóstico de la enfermedad arte rial coronaria. Sin embargo, la mayoría de los síndromes coronarios agudos involucran lesiones angiográficamente no significativas. Es también la técnica de elección para guiar la implantación de prótesis endovasculares y su seguimiento. La tomografía de coherencia óptica es una técnica de imagen interferométrica que penetra en los tejidos alrededor de 2-3 mm y ofrece una alta resolución axial. Es capaz de distinguir diferentes tipos de tejido, como fibroso, lipídico, necrótico o calcificado, reconoce características de las placas de ateroma que se han asociado con progresión rápida de la lesión y eventos clínicos adversos, como la delgada capa de fibroateroma, el espesor de la capa fibrosa, la infiltración de macrófagos y la formación de trombos. En la actualidad, existe un creciente interés en el valor de la tomografía de coherencia óptica en el área de intervención coronaria, donde la técnica ofrece ventajas significativas sobre las técnicas intravasculares de diagnóstico convencionales, como la ecografía intravascular. Su alta resolución permite reconocer las complicaciones periprocedimiento, como microdisección, malaposición e hiperplasia neointimal, haciendo de esta herramienta una de las técnicas más prometedoras en el diagnóstico intravascular.

Coronary angiography is the reference technique for the diagnosis of coronary disease. However, the majority of acute coronary syndromes involve angiographically non- significant lesions. It is also the technique of choice for guiding the implantation of endovascular prostheses and their later monitoring. Optical coherence tomography is an interferometric imaging technique that penetrates tissue approximately 2-3 mm and provides axial and lateral resolution. It is able to distinguish different tissue types, such as fibrous, lipid-rich, necrotic, or calcified tissue. Optical coherence tomography is able to recognize a variety of features of athe- rosclerotic plaques that have been associated with rapid lesion progression and clinical events, such as thin cap fibroatheroma, fibrous cap thickness, dense macrophage infiltration, and thrombus formation. Currently, there is growing interest in the value of optical coherence tomography in the area of coronary intervention, where the technique offers significant advantages over more widespread intravascular diagnostic techniques such as intravascular ultrasound. Its higher resolution permits to recognize periprocedural complications, such as microdissection of the coronary artery, stent malapposition, and neointimal hiperplasia, making this tool one of the most promising techniques in the intravascular diagnosis.

A feasibility study in 3.0 T MR imaging using an improved intravascular coil / 中华放射学杂志

Objective The study was to investigate the feasibility of using an intravascular Loopless Monopole Antenna (ILMA) for 3.0 T MR imaging of water bath and deep-seated arterial walls of experimental animal.Methods A novel intravascular loopless monopole antenna (ILMA) was developed,including a non-shield loach guide-wire and a matching circuit.The non-shield loach guide-wire is used as a receive antenna,with the diameter of 0.019 in( 1 in =2.54 cm) and length of 23.11 in.During the MR scanning,the ILMA was used as a receive-only probe,while body coil was used to transmit the RF pulses.Utilizing the coil in water bath and in-vivo animal experiment,we measured signal-to-noise ratio (SNR) and contrast-to-noise ratio(CNR) of artery wall using the same scanning parameter compared with phased-array coil.Results In the study,the developed novel ILMA conduced to improved SNR of imaging and much higher space resolution( 313 μm).First,the feasibility of acquiring the wall images was demonstrated on phantoms.The SNRs map generated by the matlab software showed that in comparison with the phased-array coil,ILMA generated higher SNR of the phantom wall when using the same sequences,parameters,and slices (86.8 ±0.8 vs.9.9 ±0.1,P ＜0.01 ).When imaging the aorta wall with the ILMA and phased-array coil,the SNRs of the arterial wall with the ILMA is 60.4 ±20.9,61.3 ±22.5,59.8 ±20.4,32.3 ±22.6 (T1WI),51.2 ±21.6,49.8 ± 15.5,50.4 ± 17.2,22.4 ± 18.3 (T2WI),the CNRs of the aorta wall with theILMA is 19.8±8.1,18.9±9.2,19.6±11.8,20.7 ± 13.3(T1WI),17.7±6.4,18.6±6.9,17.2 ± 6.4,17.2 ± 6.4 ( T2 WI),compared with phased-array coil,t values SNR:6.36,3.84,3.51,6.92(T1 WI),3.47,4.89,6.35,4.21 (T2WI),CNR:3.56,3.97,-0.71,4.74 (T1WI),3.99,3.01,4.27,5.03(T2 WI,P ＜ 0.05 ),respectively.Conclusion The study demonstrates the capability of using an MR ILMA to generate 3.0 T MR in-vivo experiments,the developed novel ILMA conduces to increased SNR compared with the conventional phased-array coil.

Uso da tomografia de coerência ótica intracoronariana para caracterização precisa da aterosclerose / Uso de la tomografía de coherencia óptica intracoronaria para caracterización precisa de la aterosclerosis / Use of optical coherence tomography for accurate characterization of atherosclerosis

A Tomografia de Coerência Ótica (TCO) é uma nova tecnologia de imagem baseada em interferometria de baixa coerência que utiliza a dispersão de luz quase-infravermelha como uma fonte de sinal para fornecer imagens transversais vasculares com definição muito superior à de qualquer outra modalidade disponível. Com uma resolução espacial de até 10μm, a TCO fornece uma resolução 20 vezes maior do que o ultrassom intravascular (USIV), a modalidade atualmente mais utilizada para obter imagens intra-coronárias. A TCO tem uma capacidade de fornecer um entendimento das várias fases da doença aterosclerótica e a resposta vascular ao tratamento. Estudos tem mostrado a capacidade da TCO em detectar estruturas arteriais e ajudar na determinação de diferentes constituintes histológicos. Sua capacidade de distinguir diferentes graus de alterações ateroscleróticas e os vários tipos de placas, quando comparada à histologia, tem sido recentemente demonstrada com correlações inter e intra-observador aceitáveis para esses achados. A TCO fornece uma resolução endovascular excepcional em tempo real in vivo, que tem sido explorada para avaliar as estruturas vasculares e a resposta ao uso do equipamento. Embora a profundidade permaneça uma limitação para a caracterização de placa além de 2 mm através da TCO, uma resolução próxima à histológica pode ser obtida dentro do primeiro milímetro da parede do vaso, permitindo uma avaliação extraordinária das características e espessura da capa fibrosa. Além disso, a avaliação da cobertura de neoíntima, padrões de tecido para-haste e aposição de stent podem agora ser escrutinizados para hastes individuais na escala de mícrons, a assim chamada análise em nível de haste. A TCO levou a imagem intravascular ao nível de mícron na análise vascular in vivo e espera-se que breve se torne uma ferramenta valiosa e indispensável para cardiologistas em aplicações clínicas e de pesquisa.

Optical coherence tomography (OCT) is a novel imaging technology based on low-coherence interferometry that uses scattering of near-infrared light as a signal source to provide vascular cross-sectional imaging with definition far superior to any other available modality. With spatial resolution of up to 10μm, OCT provides 20-fold higher resolution than intravascular ultrasound (IVUS), currently the most used modality for intra-coronary imaging. OCT has the capacity to provide invaluable insight into the various phases of atherosclerotic disease and vascular response to therapeutics. Studies have shown the ability of OCT to detect arterial structures and assist in the determination of different histological constituents. Its capacity to distinguish different grades of atherosclerotic changes and the various types of plaques, as compared to histology, has recently been demonstrated with acceptable intra-observer and inter-observer correlations for these findings. OCT provides unrivaled real-time in vivo endovascular resolution, which has been exploited to assess the vascular structures and response to device deployment. While depth remains a limitation for OCT plaque characterization beyond 2-mm, near-histological resolution can be achieved within the first millimeter of the vessel wall allowing unique assessment of fibrous cap characteristics and thickness. In addition, assessment of neointimal coverage, para-strut tissue patterns and stent apposition can now be scrutinized for individual struts on the micron scale, the so-called strut-level analysis. OCT has propelled intravascular imaging into micron-level in vivo vascular analysis and is expected to soon become a valuable and indispensable tool for the cardiologists on both clinical and research applications.

La Tomografía de Coherencia Óptica (TCO) es una nueva tecnología de imagen basada en interferometría de baja coherencia que utiliza la dispersión de luz casi infrarroja como una fuente de señal para suministrar imágenes transversales vasculares con definición muy superior a la de cualquier otra modalidad disponible. Con una resolución espacial de hasta 10 μm, la TCO ofrece una resolución 20 veces mayor que la ecografía intravascular (EIV), la modalidad actualmente más utilizada para obtener imágenes intracoronarias. La TCO tiene capacidad de suministrar comprensión de las varias fases de la enfermedad aterosclerótica y la respuesta vascular al tratamiento. Estudios han mostrado la capacidad de la TCO para detectar estructuras arteriales y ayudar en la determinación de diferentes constituyentes histológicos. Su capacidad para distinguir diferentes grados de alteraciones ateroscleróticas y los varios tipos de placas, cuando se la compara con la histología, ha sido demostrada recientemente con correlaciones inter e intra observador aceptables para esos hallazgos. La TCO ofrece una resolución endovascular excepcional en tiempo real in vivo, que se ha explorado para evaluar las estructuras vasculares y la respuesta al auso del equipamiento. Aunque la profundida continúe siendo una limitación para la caracterización de placa más allá de 2 mm a través de la TCO, una resolución próxima a la histológica puede obtenerse dentro del primer milímetro de la pared del vaso, permitiendo una evaluación extraordnaria de las característica y espesor de la capa fibrosa. Además de ello, la evaluación de la cobertura de neoíntima, patrones de tejido para vástago y aposición de stent pueden ahora ser escrutados para vástagos individuales en la escala de micrones, el llamado análisis a nivel de vástago.