The Pivot Mandu is an innovative device featuring a leak-tight adjustable 3D balloon spacer, incorporating inner mesh support, an outer e-PTFE layer, and a compliant balloon in the middle layer with a specialized detachable system. To assess its feasibility, proof of concept was rigorously evaluated through bench testing and survival porcine animal experiments. The results demonstrated successful remote inflation of the balloon system, with the balloon spacer exhibiting sustained patent and functional integrity over an extended observation period of up to 6 months. A noteworthy feature of the newly designed 3D balloon spacer is its capability for easy size adjustment during procedures, enhancing its adaptability and practicality in clinical settings. This three-layered 3D balloon spacer, with its established long-term patency, exhibits highly encouraging outcomes that hold promise in overcoming the current limitations of spacer devices for heart valve diseases. Given the compelling results from preclinical investigations, the translation of the Pivot Mandu into human trials is strongly warranted.

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.

Background: Current treatments for hypertrophic obstructive cardiomyopathy (HOCM), including medication, surgery, and alcohol septal ablation (ASA), have limitations in terms of efficacy and safety. To address these challenges, we developed the trans-coronary intra-septal radiofrequency ablation (TIRA) device. Methods: This first-in-human trial was conducted to assess the efficacy and safety of the TIRA device. Moreover, evaluations were conducted before the procedure and at 3, 6, and 12 months post-procedure using computed tomography, magnetic resonance imaging, echocardiography, and the 6 min walk distance (6MWD) test. Results: Four patients were enrolled, and follow-up imaging at 3, 6, and 12 months showed a reduction in the interventricular septal (IVS) thickness (baseline mean: 22.6 mm; 12-month mean: 18.9 mm) and a decrease in the LVOT pressure gradient at 12 months (resting baseline mean: 84.64 mmHg; resting 12-month mean: 43.56 mmHg; Valsalva baseline mean: 129.96 mmHg; Valsalva 12-month mean: 108.16 mmHg). However, reductions in the IVS thickness on echocardiography and improvements in 6MWD were observed in only two patients. Conclusions: No significant adverse events, such as arrhythmias or vascular injuries, were reported. These findings suggest that the TIRA device may be a safe and effective option for treating HOCM. However, further studies are required to confirm these results.

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.

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.