Search Results (189)

Aim: Hostile aortic neck anatomy—characterized by short neck length, severe angulation, conical shape, and mural thrombus or calcifications—represents a major limitation to the durability and applicability of standard endovascular aneurysm repair (EVAR). In response to these challenges, newer endografts with improved conformability have been developed. This study aimed to evaluate the mid-term outcomes of EVAR using the GORE EXCLUDER Conformable AAA Endoprosthesis (CEXC) (W.L. Gore & Associates Inc., Flagstaff, AZ, USA) in patients with hostile neck anatomy, with specific attention to type III endoleak occurrence, aortic sac remodeling, and maintenance of distal sealing. Methods: A retrospective observational analysis was conducted on 50 consecutive patients treated with the CEXC endograft between October 2019 and September 2023. Patients included had either elective or urgent indications for EVAR and were evaluated preoperatively using CT angiography. Hostile neck criteria were defined according to the 2019 Delphi Consensus. Procedural variables, imaging follow-up, and clinical outcomes were collected. The primary endpoints were technical and clinical success, while secondary outcomes included endoleak rates, aneurysm sac evolution, and reintervention-free survival. Results: Technical success was achieved in 100% of cases, with a clinical success rate of 98%. No type Ia, Ib, or III endoleaks were observed at a median follow-up of 23 months. Sac shrinkage (>5 mm reduction) occurred in 70% of patients, and distal sealing was preserved in 100% of cases. One perioperative death occurred in an emergency setting, and no late reinterventions or aneurysm-related mortalities were reported. The use of intravascular ultrasound (IVUS) and floppy guidewires contributed to precise deployment and sealing in angulated anatomies. Conclusions: The CEXC endograft proved to be a safe and effective option for EVAR in patients with hostile aortic anatomy, ensuring durable proximal and distal sealing, promoting favorable sac remodeling, and preventing type III endoleaks. These findings support the use of CEXC in anatomically complex settings, as long as procedures are meticulously planned and guided by appropriate intraoperative imaging and deployment techniques. Full article

Intravascular aspiration thrombectomy catheters are widely used to treat stroke, pulmonary embolism, and deep venous thrombosis. However, their performance is frequently compromised by clot material becoming lodged within the catheter tip. To address this, we develop a novel ultrasound-enhanced aspiration catheter approach that generates cavitation within the tip to mechanically degrade clots, with a view to facilitate extraction. The design employs hollow cylindrical transducers that produce inwardly propagating cylindrical waves to generate sufficiently high pressures to perform histotripsy. This study investigates the feasibility of self-sensing cavitation detection by analyzing voltage signals across the transducer during treatment. Experiments were conducted for two transmit pulse lengths at varying driving voltages with water or clot in the lumen. Cavitation clouds within the lumen were assessed using 40 MHz ultrasound imaging. Changes in the signal envelope during the pulse body and ringdown phases occurred above the cavitation threshold, the latter being associated with more rapid wave damping in the presence of bubble clouds within the lumen. In the frequency domain, voltage-dependent cavitation signals—subharmonics, ultra-harmonics, and broadband—emerged alongside transmit pulses. This work demonstrates a highly sensitive, sensor-free method for detecting cavitation within the lumen, enabling feedback control to further improve histotripsy-assisted aspiration. Full article

Acute pulmonary embolism (APE) represents a significant cause of morbidity and mortality worldwide, requiring rapid and precise diagnosis and effective therapy strategies. Computed Tomography Pulmonary Angiography (CTPA) is currently the gold standard technique for diagnosing PE; however, it presents some disadvantages, including limited sensitivity in detecting sub-segmental emboli and contrast-related risks. Recent advancements in imaging technologies, including Dual-Energy Computed Tomography (DECT) and Photon Counting (PC), offer improved sensitivity and specificity for APE and perfusion abnormalities detection. Digital Dynamic Radiography (DDR) perfusion imaging represents a novel imaging that allows pulmonary perfusion assessment without contrast medium administration, able to detect anomalies at the patient’s bedside, representing a promising advancement, particularly for critically ill or contrast-allergic patients. In parallel, interventional radiology has become integral to APE management, particularly for high-risk and intermediate–high-risk patients, with evolving intravascular treatment techniques such as catheter-directed thrombolysis, mechanical thrombectomy, and thrombus aspiration. This narrative review provides an overview of the latest developments in APE diagnostic imaging and interventional radiology, contextualizing them within current guideline recommendations for endovascular treatment. Full article

Percutaneous Coronary Intervention (PCI) has advanced significantly with the incorporation of imaging and physiology assessment techniques. Fractional Flow Reserve (FFR) and Non-Hyperemic Pressure indices (NHPIs) provide information regarding the functional significance of coronary lesions, while Intravascular Ultrasound (IVUS) and Optical Coherence Tomography (OCT) enhance anatomical characterization and guide stent implantation. This review explores the implementation of physiology- and imaging-guided strategies in clinical practice, comparing their efficacy and limitations. Novel technologies now allow for physiology estimation without hyperemic agents, and hybrid techniques, such as OCT-derived FFR, are increasingly integrated into clinical practice. These approaches offer the combined advantages of functional assessment and detailed anatomical imaging. Full article

Optical Coherence Tomography (OCT) has evolved from a breakthrough ophthalmologic imaging tool into a cornerstone technology in interventional cardiology. After its initial applications in retinal imaging in the early 1990s, OCT was subsequently envisioned for cardiovascular use. In 1995, its ability to visualize atherosclerotic plaques was demonstrated in an in vitro study, and the following year marked the acquisition of the first in vivo OCT image of a human coronary artery. A major milestone followed in 2000, with the first intracoronary imaging in a living patient using time-domain OCT. However, the real inflection point came in 2006 with the advent of frequency-domain OCT, which dramatically improved acquisition speed and image quality, enabling safe and routine imaging in the catheterization lab. With the advent of high-resolution, second-generation frequency-domain systems, OCT has become clinically practical and widely adopted in catheterization laboratories. OCT progressively entered interventional cardiology, first proving its safety and feasibility, then demonstrating superiority over angiography alone in guiding percutaneous coronary interventions and improving outcomes. Today, it plays a central role not only in clinical practice but also in cardiovascular research, enabling precise assessment of plaque biology and response to therapy. With the advent of artificial intelligence and hybrid imaging systems, OCT is now evolving into a true precision-medicine tool—one that not only guides today’s therapies but also opens new frontiers for discovery, with vast potential still waiting to be explored. Tracing its historical evolution from ophthalmology to cardiology, this narrative review highlights the key technological milestones, clinical insights, and future perspectives that position OCT as an indispensable modality in contemporary interventional cardiology. As a guiding thread, the myth of Prometheus is used to symbolize the evolution of OCT—from its illuminating beginnings in ophthalmology to its transformative role in cardiology—as a metaphor for how light, innovation, and knowledge can reveal what was once hidden and redefine clinical practice. Full article

Optical Coherence Tomography (OCT) is a further light-based intravascular imaging modality and provides a high-resolution, cross-sectional view of coronary arteries. It has a useful anatomic and increasingly physiological evaluation in light of coronary artery disease (CAD). This review provides a critical examination of the increased application of the OCT in assessing coronary artery physiology, beyond its initial mainstay application in anatomical imaging. OCT provides precise information on plaque morphology, which can help identify vulnerable plaques, and is most important in informing percutaneous coronary interventions (PCIs), including implanting a stent and optimizing it. The combination of OCT and functional measurements, such as optical flow ratio and OCT-based fractional flow reserve (OCT-FFR), permits a more complete assessment of coronary stenoses, which may provide increased diagnostic accuracy and better revascularization decision-making. The recent developments in OCT technology have also enhanced the accuracy in the measurement of coronary functions. The innovations may support the optimal treatment of patients as they provide more personalized and individualized treatment options; however, it is critical to recognize the limitations of OCT and distinguish between the hypothetical advantages and empirical outcomes. This review evaluates the existing uses, technological solutions, and future trends in OCT-based physiological imaging and evaluation, and explains how such an advancement will be beneficial in the treatment of CAD and gives a fair representation concerning other imaging applications. Full article

Spontaneous coronary artery dissection (SCAD) is an increasingly recognized, non-atherosclerotic cause of acute coronary syndrome (ACS), particularly in younger women. This comprehensive review outlines SCAD’s unique pathophysiology, which is linked to underlying arteriopathies like fibromuscular dysplasia, and highlights the critical role of advanced intravascular imaging for accurate diagnosis. A fundamental shift in management is detailed, with evidence favoring a conservative strategy for stable patients due to high rates of spontaneous vessel healing, reserving technically challenging invasive interventions for high-risk cases. Importantly, this review also addresses long-term outcomes, noting significant rates of recurrence and Major Adverse Cardiac Events (MACE), a high prevalence of persistent chest pain, and the central role of beta-blocker therapy in secondary prevention. Ultimately, SCAD requires a departure from standard ACS protocols towards a personalized approach that emphasizes accurate diagnosis, cautious initial management, and vigilant long-term follow-up. Full article

The right heart–pulmonary circulation unit (RH-PCU) constitutes an integrated anatomo-functional system characterized by high-volume blood flow, low intravascular pressure, and minimal pulmonary vascular resistance. The RH-PCU dysfunction is a challenge for clinicians, as it can result from numerous pathological conditions, each with different clinical presentations. The pathophysiological changes underlying the hemodynamic alterations in the pressure and volume affecting the right ventricle can lead the patient to present with the primary symptom: dyspnea. We review the clinical presentation, the laboratory test, and the role of multimodality imaging in the evaluation of the disfunction of the RHPCU, including echocardiography, stress echocardiography, computed tomography, magnetic resonance imaging, nuclear imaging, and invasive pressure measurement through catheterization. We therefore aimed to describe the various diagnostic options available to clinicians, evaluating their effectiveness and limitations of use. Full article

Coronary artery disease (CAD) is the third leading cause of disability and death globally. Intravascular ultrasound (IVUS) is the most commonly used imaging modality for the characterization of vulnerable plaques. The development of novel intravascular imaging and therapy devices requires dedicated open systems (e.g., for pulse sequences for imaging or thrombolysis), which are not currently available. This paper presents the development of a novel multifunctional FPGA-based pulser/receiver system for intravascular ultrasound imaging and therapy research. The open platform consists of a host PC with a Matlab-based software interface, an FPGA board, and a proprietary analog front-end board with state-of-the-art electronics for highly flexible transmission and reception schemes. The main features of the system include the capability to convert arbitrary waveforms into tristate bipolar pulses by using the PWM technique and by the direct acquisition of raw radiofrequency (RF) echo data. The results of a multicycle excitation pulse applied to a custom 550 kHz therapy transducer for acoustic characterization and a pulse-echo experiment conducted with a high-voltage, short-pulse excitation for a 19.48 MHz transducer are reported. Testing results show that the proposed system can be easily controlled to match the frequency and bandwidth required for different IVUS transducers across a broad class of applications. Full article

Coronary plaque vulnerability, more than luminal stenosis, drives acute coronary syndromes. Optical coherence tomography (OCT), intravascular ultrasound (IVUS), and coronary computed tomography angiography (CCTA) visualize plaque morphology in vivo, but manual interpretation is time-consuming and operator-dependent. We performed a narrative literature survey of artificial intelligence (AI) applications—focusing on machine learning (ML) architectures—for automated coronary plaque segmentation and risk characterization across OCT, IVUS, and CCTA. Recent ML models achieve expert-level lumen and plaque segmentation, reliably detecting features linked to vulnerability such as a lipid-rich necrotic core, calcification, positive remodelling, and a napkin-ring sign. Integrative radiomic and multimodal frameworks further improve prognostic stratification for major adverse cardiac events. Nonetheless, progress is constrained by small, single-centre datasets, heterogeneous validation metrics, and limited model interpretability. AI-enhanced plaque assessment offers rapid, reproducible, and comprehensive coronary imaging analysis. Future work should prioritize large multicentre repositories, explainable architectures, and prospective outcome-oriented validation to enable routine clinical adoption. Full article

Coronary chronic total occlusions (CTOs) are diagnosed in a significant portion of patients undergoing coronary angiography and represent one of the most complex scenarios in contemporary percutaneous coronary interventions (PCI). This review systematically examines how adjunctive imaging modalities’—intravascular ultrasound (IVUS), optical coherence tomography (OCT), and coronary computed tomography angiography (CCTA)—co-registration enhances the precision and success rates of CTO-PCI during the procedure. The strategic integration of these technologies enables the development of patient-specific intervention strategies tailored to individual vascular architecture and lesion characteristics. This personalized approach marks a transition from standardized protocols to precision interventional cardiology, potentially optimizing procedural success rates while minimizing complications. Full article

Background: Although contemporary stent technology has significantly evolved, a substantial number of patients present with stent failure (SF), the clinical expression of which is either in-stent restenosis (ISR) or stent thrombosis (ST). Methods: In this observational, single-center study, we aimed to compare the clinical characteristics, clinical presentation, angiographic findings and subsequent management of patients who underwent percutaneous coronary intervention (PCI) for SF, either ISR or ST, with patients who had PCI for de novo lesions. Results: Over a period of two years (September 2022–October 2024), 1120 patients underwent PCI, of whom 9% had SF. Of the 101 SF cases, the majority (76 cases, 75%) had ISR, while the rest (25 cases, 25%) had ST. Regarding baseline characteristics, patients who underwent PCI for SF had a higher incidence of diabetes mellitus (53% vs. 29%; p < 0.001), dyslipidemia (88% vs. 50%; p < 0.001) as well as prior coronary artery bypass grafting surgery (7.9% vs. 3.7%; p = 0.043), while they were less likely to be current smokers (33% vs. 52%; p < 0.001). SF PCI patients presented more frequently with unstable angina (17% vs. 8.9%; p = 0.010). A new stent was implanted in less than half of SF cases (i.e., stent implantation, 44% vs. 91%; p < 0.001). On the other hand, in the clinical setting of SF, drug-coated balloons (44% vs. 5.3%; p < 0.001) and plain balloon angioplasty (8.9% vs. 0.7%; p < 0.001) was applied more frequently compared with de novo lesions. Furthermore, the usage of cutting/scoring balloons and lithotripsy was significantly higher in the SF group (8.9% vs. 0.4% and 12% vs. 3%, respectively; p < 0.001 for both). Intracoronary imaging guidance was more commonly used in the SF group (33% vs. 13%; p < 0.001). Stent malapposition (44%) and neoatherosclerosis (67%) were the most common mechanisms of ST and ISR, respectively, as identified by intravascular imaging modalities. Finally, the success rates were comparable (96% vs. 98%; p = 0.150) between the two groups. Conclusions: Approximately one of ten patients underwent PCI because of the failure of a previously implanted stent. Use of intracoronary imaging is significantly higher in the clinical context of SF. While DES implantation remains the standard of practice for de novo lesions, DCBs are a popular alternative, especially for ISR cases. Interventional cardiologists who are involved in the treatment of SF cases should be familiar with interpreting intravascular imaging to guide the use of the adjunctive device required to ensure that optimal procedural results in SF cases are obtained. Full article

Intravascular imaging (IVI) has emerged as a pivotal tool in percutaneous coronary intervention (PCI), offering superior visualization of coronary anatomy compared with conventional angiography. This literature review synthesizes the latest evidence from randomized trials and meta-analyses published since 2022, assessing the comparative efficacy of IVI modalities—including intravascular ultrasound (IVUS) and optical coherence tomography (OCT)—in complex coronary lesions. Multiple landmark trials, such as RENOVATE-COMPLEX PCI, ILUMIEN IV, OCTOBER, and OCTIVUS, demonstrated that IVI-guided PCI significantly improves procedural outcomes, stent optimization, and clinical endpoints such as target-vessel failure, myocardial infarction, and stent thrombosis. OCT was shown to be particularly beneficial in bifurcation and left main interventions, while IVUS consistently improved outcomes in long lesions and complex anatomies. Despite some trials not meeting their primary clinical endpoints, substudy findings and pooled analyses support a shift toward routine IVI use in anatomically complex cases. Consequently, updated guidelines now recommend IVI as a Class I indication in select patient populations. These findings underscore the need for broader clinical adoption and training in IVI techniques to enhance PCI outcomes. Full article

Chronic total occlusions (CTOs), defined as complete coronary artery blockages persisting for over three months, are frequently encountered in up to 25% of coronary angiograms. Although percutaneous coronary intervention (PCI) for CTO remains technically challenging, advancements in guidewires, microcatheters, re-entry devices, and intravascular imaging, along with the expertise of specialized operators, have significantly improved procedural success rates, now exceeding 90% in expert centers. While recent evidence, such as the SYNTAX II study, emphasizes the importance of complete revascularization, over half of CTO cases continue to be managed conservatively with optimal medical therapy (OMT), partly due to the limited high-quality randomized evidence supporting revascularization. Observational studies have demonstrated that successful CTO-PCI is associated with improved angina relief, quality of life, left ventricular function, and possibly long-term survival. Extended observational follow-up, such as the Korean and Canadian registries, suggests long-term reductions in cardiac and all-cause mortality with CTO revascularization. However, randomized controlled trials (RCTs) have primarily shown symptomatic benefit, with no consistent reduction in major adverse cardiac events (MACE) or mortality, likely due to limited sample sizes, short follow-up, and treatment crossovers. Various strategies, including the hybrid algorithm, guide CTO interventions by balancing antegrade and retrograde techniques based on lesion complexity. Imaging modalities such as coronary CT angiography and intravascular ultrasound play a pivotal role in planning and optimizing these procedures. Future innovations, such as real-time fusion imaging of CCTA with coronary angiography, may enhance lesion visualization and guidewire navigation. While current guidelines recommend CTO-PCI in selected symptomatic patients with demonstrable ischemia or viable myocardium, the decision should be individualized, incorporating anatomical feasibility, comorbidities, patient preferences, and input from a multidisciplinary Heart Team. Looking ahead, adequately powered RCTs with extended follow-up are essential to determine the long-term clinical impact of CTO-PCI on hard outcomes such as mortality and myocardial infarction. Full article

Cardiac allograft vasculopathy (CAV) is a leading cause of allograft dysfunction and failure. CAV prevention, early detection, and management are essential to increasing allograft survival. In this comprehensive review, we discuss various invasive and non-invasive modalities that are being utilized for CAV detection. Invasive coronary angiography provides a visualization of vascular anatomy but is limited in detecting the microvasculature and diffuse and early structural changes. The addition of intracoronary assessment techniques, including intravascular ultrasound, optical coherence tomography, and coronary flow reserve assessment, offer(s) superior sensitivity in identifying CAV. Non-invasive imaging modalities, such as cardiac magnetic resonance imaging, computed tomography angiography, and positron emission tomography, provide complementary insights into CAV with myocardial perfusion and allograft function while reducing procedural risks. Our aim is to guide clinicians in selecting appropriate imaging strategies tailored to individual recipients, to improve detection, monitoring, and outcomes in CAV. Full article