Min Ku Chon

Background: The management of severe tricuspid regurgitation (TR) remains challenging. Although several promising transcatheter devices have been developed, procedural complexity and the need for special imaging techniques are hurdles to their widespread clinical application. Aims: The study aimed to evaluate the safety and efficacy of a novel atraumatic vertical spacer, Pivot‐Bridge, for severe TR. Methods: Patients with severe TR who were considered surgical candidates were enrolled. All procedures were guided by fluoroscopy and transthoracic echocardiography (TTE). Baseline characteristics, serious adverse events, and functional status were collected. TTE and cardiac computed tomography (CT) were serially performed for evaluation of TR and right ventricular (RV) remodeling. Results: Fifteen patients (68 ± 11 years old, 27% women) were enrolled. Procedural success was achieved in all patients (the mean procedural time of 47 ± 24 min). During the device implantation (median 5 days), no serious adverse events occurred. TR was reduced by one grade or more in all patients. In TTE, vena contracta width and effective regurgitant orifice area significantly decreased by Pivot‐Bridge (1.6 ± 0.8 to 0.8 ± 0.3 mm; p < 0.001 and 1.2 ± 0.5 to 0.6 ± 0.3 cm ² ; p < 0.001). RV end diastolic volume also significantly reduced at follow‐up CT (320.2 ± 93.7 to 294.4 ± 81.1 mm ³ ; p = 0.026). Ten patients underwent surgery with removal of the device, and five patients were stabilized by medical treatment, in whom the Pivot‐Bridge was removed percutaneously. Conclusions: The Pivot‐Bridge was safe and effective in patients with severe TR. TR reduction was observed in all patients without periprocedural complications or adverse cardiovascular events during device placement. Registration: ClinicalTrials.gov number: NCT05854095.

Polyurethane-based implantable devices (PUIDs) delivered via catheter are increasingly used in structural heart interventions; however, limited in vivo data exist regarding their long-term biostability and biological safety. This study evaluated a balloon-shaped implant made of Pellethane^®, a polyether-based polyurethane, designed as a three-dimensional intracardiac spacer and deployed via percutaneous femoral vein access. The device was chronically positioned adjacent to the tricuspid valve annulus in seven pigs for 24 weeks. Explanted devices and surrounding tissues were evaluated through material characterization (SEM, GPC, FT-IR, and ¹H-NMR) and histological analysis. SEM and FT-IR confirmed preserved surface morphology and chemical bonds, GPC showed stable molecular weight, and ¹H-NMR revealed intact urethane and ether linkages. Materials characterization revealed no evidence of hydrolytic or oxidative degradation, indicating structural stability of the devices. Histological analysis showed stable device positioning with minimal thrombosis or inflammatory response. Biocompatibility was confirmed via ISO 10993-1:2018 Standard (International Organization for Standardization (ISO): Geneva, Switzerland, 2018), and extractable substances were evaluated under exhaustive extraction conditions specified by ISO 10993-18:2020 (International Organization for Standardization (ISO): Geneva, Switzerland, 2020), with no toxicologically significant findings. These findings support the long-term biostability and biological safety of the PUIDs in dynamic cardiac environments, informing future design criteria for catheter-delivered cardiovascular devices.

Revascularization remains an important component of chronic coronary syndrome (CCS) management, particularly in patients with high-risk coronary anatomy, impaired left ventricular (LV) function, or persistent symptoms despite guideline-directed medical therapy. Evidence indicates that prognostic benefit is most pronounced in patients with left main disease, multivessel disease, proximal left anterior descending artery involvement, and severe LV systolic dysfunction. In other patients, revascularization primarily improves angina symptoms and quality of life. The choice between percutaneous coronary intervention (PCI) and coronary artery bypass grafting should be individualized according to coronary anatomy, clinical risk, comorbidities, and the likelihood of complete revascularization. Contemporary PCI increasingly incorporates coronary physiology and intravascular imaging to refine lesion selection and improve procedural outcomes. Long-term CCS management requires structured follow-up to detect disease progression, recurrent ischemia, revascularization failure, and cardiovascular complications. Routine surveillance testing is not recommended in asymptomatic patients after PCI. Instead, follow-up should be tailored to patient risk and clinical status. When complete revascularization fails, mechanisms such as stent thrombosis, in-stent restenosis, graft failure, and progression of untreated coronary disease should be identified; intravascular imaging has an important role in guiding repeat revascularization. Comprehensive CCS management should also address complications, including heart failure, ventricular arrhythmias, and secondary valvular disease, through a multidisciplinary, patient-centered approach.

Coronary artery disease is one of the leading causes of death worldwide and represents a major health burden in Korea. Chronic coronary syndrome (CCS) encompasses the long-term and heterogeneous clinical manifestations of ischemic heart disease, ranging from obstructive epicardial disease to non-obstructive and microvascular disease. This pathophysiological heterogeneity necessitates individualized diagnostic and therapeutic strategies to prevent progression from CCS to acute coronary syndrome. Since the publication of recent CCS guidelines, new evidence has emerged regarding optimal diagnostic strategies, physiological and intravascular imaging-based assessments, and medical therapy. In addition, contemporary CCS management increasingly emphasizes multidisciplinary integration, including cardiovascular prevention, non-invasive imaging-guided decision-making, and patient-centered revascularization strategies. However, the implementation of these principles in real-world Korean clinical practice remains unclear, highlighting the need for localized, evidence-based guidance for Korean patients with CCS. This expert consensus provides a comprehensive, stepwise framework for the diagnosis, treatment, and long-term management of CCS by integrating the latest international evidence with Korean clinical data and practice patterns.

Lee SH, et al. J Cardiovasc Interv. 2026 ;5:e34. https://doi.org/10.54912/jci.2026.0019

Lee JM, et al. J Cardiovasc Interv. 2026 ;5:e33. https://doi.org/10.54912/jci.2026.0018

Kim SH, et al. Korean Circ J. 2026 ;56:e66. https://doi.org/10.4070/kcj.2025.0266

Polyurethane-based implantable devices(PUIDs) delivered via catheter are increasingly used in structural heart interventions; however, limited in vivo data exist regarding their long-term biostability and biological safety. This study evaluated a balloon-shaped implant made of Pellethane^®, a polyether-based polyurethane, designed as a three-dimensional intracardiac spacer and deployed via percutaneous femoral vein access. The device was chronically positioned adjacent to the tricuspid valve annulus in seven pigs for 24 weeks. Explanted devices and surrounding tissues were evaluated through material characterization (SEM, GPC, FT-IR, and ¹H-NMR) and histological analysis. SEM and FT-IR confirmed preserved surface morphology and chemical bonds, GPC showed stable molecular weight, and ¹H-NMR revealed intact urethane and ether linkages. Materials characterization revealed no evidence of hydrolytic or oxidative degradation, indicating structural stability of the devices. Histological analysis showed stable device positioning with minimal thrombosis or inflammatory response. Biocompatibility was confirmed via ISO 10993-1:2018 Standard, and extractable substances were evaluated under aggressive extraction conditions specified by ISO 10993-18:2020, with no toxicologically significant findings. These findings support the long-term biostability and biological safety of the PUIDs in dynamic cardiac environments, informing future design criteria for catheter-delivered cardiovascular devices.

Radiofrequency ablation (RFA) is a pivotal therapeutic technique for various medical conditions, including cardiovascular disease and oncological conditions such as liver and lung cancer. The energy-controlled mode in RFA procedures allows for uniform energy delivery but is less safe compared to the temperature-controlled mode. Therefore, it is necessary to develop a protocol that ensures safety while efficiently delivering energy in the temperature-controlled mode. In this study, we compared lesion formation using the gradual-temperature-rise mode to the fixed-temperature mode. We evaluated the lesion size, energy, cumulative time efficiency, and procedural safety in both in vitro and in vivo experiments with porcine myocardial tissue. Three experimental groups (n = 6) were compared to assess the effect of gradual-temperature-rise and fixed-temperature ablation modes. Five experimental groups (n = 6) were used to determine the optimal temperature turn-up time. The gradual-temperature-rise mode ablated larger lesions (10.48 ± 0.56 mm) compared to the 75 °C (7.67 ± 0.37 mm) and 85 °C (8.05 ± 0.36 mm) fixed-temperature groups (p = 0.002). The optimal turn-up time for efficient lesion formation was found to be between 120 and 180 s. The in vivo experiments validated the safety and efficacy of the optimized gradual-temperature-rise mode. Therefore, using the gradual-temperature-rise mode of temperature-controlled RFA enhances lesion formation, energy transfer, and safety, making it a promising approach for clinical application in cardiac ablation procedures.

Kim EK, et al. Korean Circ J. 2024 Oct;55:e1. https://doi.org/10.4070/kcj.2024.0147