Ioannis Kachrimanidis

Background: Mitral regurgitation (MR) is one of the most prevalent valvular heart diseases, with a rising global incidence. The 2025 European Society of Cardiology (ESC) guidelines introduced updated pathophysiological and morphological concepts for secondary MR, distinguishing ventricular and atrial mechanisms. Concurrent advances in cardiovascular imaging and therapeutic technologies have transformed the diagnostic and management landscape of MR. Methods: This review summarizes current evidence on the diagnosis and treatment of MR, with a focus on the updated ESC classification, multimodality cardiovascular imaging, minimally invasive surgical techniques, and contemporary transcatheter repair strategies. Recent literature was evaluated to highlight advances in anatomical assessment and individualized therapeutic approaches. Results: Multimodality imaging provides comprehensive evaluation of mitral valve anatomy, ventricular remodeling, and disease mechanisms, enabling accurate patient selection and procedural planning. Surgical management has evolved from conventional repair or replacement to minimally invasive approaches, including video-assisted right thoracotomy and robotic-assisted surgery, which have demonstrated favorable perioperative and clinical outcomes. In parallel, transcatheter interventions have expanded the therapeutic armamentarium for patients at high surgical risk or with complex anatomy. These include direct and indirect annuloplasty, transcatheter edge-to-edge repair, and emerging catheter-based repair technologies targeting specific structural abnormalities of the mitral valve apparatus. Conclusions: Contemporary management of MR requires an integrated understanding of disease pathophysiology, advanced imaging, and patient-specific anatomical characteristics. The combination of minimally invasive surgical techniques and rapidly evolving transcatheter interventions has broadened treatment options and supports a tailored, multidisciplinary approach to improve clinical outcomes and expand access to effective therapy for patients with severe MR.

Traditional cardiovascular assessment has historically focused on the isolated evaluation of either atrial or ventricular structure and function. However, the left atrioventricular coupling index (LACI) represents a paradigm shift by moving beyond single-chamber metrics to quantify the dynamic interaction between the left atrium and left ventricle. Defined as the ratio of left atrial end-diastolic volume to left ventricular end-diastolic volume, LACI integrates structural and functional aspects of cardiac performance. This comprehensive review examines the physiological basis of how the left atrium and ventricle operate as an integrated hemodynamic unit. We detail current measurement methodologies, including two- and three-dimensional echocardiography, cardiac computed tomography, and cardiac magnetic resonance imaging, which serves as the reference standard. Furthermore, the review explores the pathophysiological mechanisms driving atrioventricular uncoupling, specifically mechanical dysfunction, electromechanical desynchrony, and hemodynamic alterations. Extensive clinical evidence demonstrates LACI’s robust independent prognostic value across diverse cardiovascular conditions, such as heart failure, myocardial infarction, cardiomyopathies, and atrial fibrillation. Observational data suggest that LACI provides a promising prognostic value beyond established risk assessment tools by combining the assessment of both chambers’ interdependence. Finally, we outline future directions for clinical translation, highlighting the necessity for standardized measurement protocols, the integration of artificial intelligence, and the potential of LACI as a target for personalized therapeutic strategies.

Angiography remains the standard imaging modality during cardiac catheterization; however, this technique provides only a two-dimensional representation of the coronary lumen, which limits the assessment of vessel wall pathology. In comparison, intravascular imaging techniques, such as intravascular ultrasound (IVUS) and optical coherence tomography (OCT), provide high-resolution cross-sectional and two-dimensional reconstructions of the coronary arteries. Thus, these modalities complement angiographic findings, enable detailed evaluation of underlying pathology, and facilitate precise procedural guidance. Advancements in imaging technologies, including near-infrared spectroscopy and virtual histology intravascular ultrasound, further enhance lesion characterization and procedural planning. An increasing body of evidence from registries, randomized controlled trials, and meta-analyses supports the use of intravascular imaging-guided percutaneous coronary interventions, demonstrating improved procedural success rates and superior long-term clinical outcomes. In the context of acute coronary syndromes (ACS), OCT offers critical diagnostic insights that enhance accuracy and inform optimal treatment strategies. This review highlights the evolving role of OCT in the management of ACS and the favorable impact of this technique on patient outcomes.

Transcatheter aortic valve implantation (TAVI) has transformed the treatment of aortic valve stenosis, offering a less invasive alternative to surgical valve replacement, particularly in elderly and high-risk populations. As TAVI expands into younger, lower-risk patients, the choice of transcatheter heart valve has become increasingly important to optimize both immediate and long-term outcomes. Currently, Self-Expandable Valves (SEVs) and Balloon-Expandable Valves (BEVs) are the two most widely used platforms, each characterized by distinct design features, implantation techniques, and hemodynamic profiles. While no definitive evidence supports the overall superiority of one valve type over the other, accumulating clinical data highlight specific advantages and limitations depending on anatomical and procedural contexts. This review aims to present and critically discuss the current evidence, clinical considerations, and evolving concerns surrounding the use of SEVs versus BEVs, with a particular focus on challenging scenarios such as valve-in-valve procedures and long-term valve strategy planning.

Transcatheter aortic valve implantation (TAVI) has emerged as a transformative therapy for patients with severe aortic stenosis (AS) across all surgical risk groups. However, periprocedural cerebrovascular events (CVEs), including overt stroke and silent cerebral embolism, remain significant complications. As a result, the use of embolic protection devices (EPDs) during TAVI has been proposed to mitigate this risk. Our aim was to provide a comprehensive review of the current evidence on the efficacy, safety, and clinical utility of embolic protection devices in TAVI procedures. According to the existing literature, EPDs are effective in capturing embolic debris during TAVI and are associated with a reduction in silent cerebral lesions as detected by diffusion-weighted MRI. While some RCTs and meta-analyses demonstrate a potential benefit in reducing disabling stroke, evidence for a consistent reduction in overall stroke or mortality remains inconclusive. Subgroup analyses suggest the greatest benefit in patients at elevated stroke risk, while current-generation EPDs demonstrate high technical success and an acceptable safety profile. Subsequently, EPDs represent a promising adjunct to TAVI, particularly in high-risk populations. However, routine use in all patients is not yet supported by consistent clinical evidence. Further large-scale trials and long-term outcome data are needed to clarify their role in improving neurological outcomes and to guide selective patient application.

Pulmonary embolism (PE) remains a major cardiovascular emergency associated with significant morbidity and mortality. Despite advances in risk stratification models, accurately predicting which intermediate-high-risk patients will deteriorate remains challenging. Systemic thrombolysis, while effective in high-risk PE, is not a viable option for a significant proportion of patients due to contraindications, and its efficacy in the intermediate-high-risk group remains inconclusive. Drawing parallels from acute myocardial infarction and stroke, where percutaneous interventions have revolutionized treatment, interventional therapies are emerging as a promising alternative for PE management. However, challenges persist regarding optimal patient selection, procedural timing, and balancing efficacy with safety. The establishment of pulmonary embolism response teams (PERTs) has played a crucial role in streamlining decision-making and facilitating access to advanced therapies. As novel catheter-based techniques continue to evolve, the field of PE management is undergoing a paradigm shift, mirroring the transformation seen in acute coronary and cerebrovascular care, positioning interventional approaches at the forefront of therapy.

Transcatheter aortic valve implantation (TAVI) has emerged as a revolutionary therapeutic modality for the management of severe aortic stenosis (AS), particularly in patients who are at high or prohibitive risk for surgical aortic valve replacement (SAVR). Over the past decade, extensive clinical evidence has expanded the indications for TAVI to include intermediate- and low-risk populations, which usually represent a population of younger age, in which the most common complications of TAVI, including paravalvular leak (PVL) and pacemaker implantation, should be avoided. This review focuses on the incidence and predictors of PVL in various types of TAVI implantation, its clinical implication, and the prevention strategies to tackle this complication.

Acute coronary syndrome (ACS) represents the most severe manifestation of coronary artery disease. Intravascular imaging, both intravascular ultrasound (IVUS) and optical coherence tomography (OCT), have played crucial roles for the impressive reduction in mortality of ACS. Intravascular imaging is useful for the detection of atherosclerotic mechanism (plaque rupture, calcified nodules, or plaque erosions) and for the evaluation of nonatherosclerotic and nonobstructive types of ACS. In addition, IVUS and OCT play a crucial role in the optimization of the PCI. The aim of the current review is to present the role of intravascular imaging in identifying the mechanisms of ACS and its prognostic role in future events, to review the current guidelines suggesting intravascular imaging use in ACS, to summarize its role in PCI in patients with ACS, and to compare IVUS and OCT.