Recent advances in three-dimensional (3D) ultra-high-density mapping systems have uncovered previously unknown mechanisms underlying various arrhythmias. This clinical review, titled "3D Mapping Quest," focuses on the recently uncovered mechanisms of four types of arrhythmias. (1) To elucidate the precise mechanisms underlying atrial fibrillation (AF), ultra-high-density mapping with adequate spatial and temporal resolution is essential. Various mapping systems have been employed to investigate the chaotic activation during AF. The question remains: Is the AF driver characterized by focal activation or rotational activation? A novel mapping strategy is expected to provide the answer. (2) In atrioventricular nodal reentrant tachycardia (AVNRTs), 3D mapping revealed that the pivot point of activation at the lower end of a functional block line extending vertically downward from the His-bundle area, or a fractionated potential observed during AVNRT, can be targeted for slow pathway ablation. Either approach may prevent unnecessary radiofrequency applications while maintaining the success rate. (3) In premature ventricular contractions originating from the left ventricular summit, 3D mapping has enabled precise identification of the optimal endocardial ablation sites. By performing long-duration ablation at these optimal endocardial sites, the ablation outcomes have improved. (4) In scar-related reentrant ventricular tachycardia (VT), substrate mapping focusing on wavefront discontinuity has allowed for the identification of specific ablation targets within the broad scar. High-density VT activation mapping has revealed the complexity of the circuit structure, such as the 3D VT circuit. The VT circuit delineation on the cardiac surface is conceptualized as a cross-section of a hyperboloid model. Thus, it is anticipated that integrating histological and electrophysiological insights with advanced ultra-high-density mapping technologies will further facilitate a comprehensive understanding of the mechanisms.

The association between the clinical significance and prognostic impact of catheter-based micro-axial ventricular assist device Impella (Abiomed, Danvers, MA, USA) support and age has not been sufficiently investigated.

Current guidelines strongly recommend the application of primary percutaneous coronary intervention (PCI) in patients with acute myocardial infarction; however, information on its efficacy in super-old patients aged >90 years is inadequate. We compared the efficacy of primary PCI and its clinical outcomes in super-old patients with those of old patients in a super-aging society.

Immunoglobulin light-chain (AL) amyloidosis is a lethal condition resulting from misfolded immunoglobulin ALs produced by clonal CD38-positive plasma cells. Treatment with daratumumab, an anti-human CD38 monoclonal antibody, led to higher frequencies of complete hematologic response and better clinical outcomes compared with conventional treatment. This study sought to evaluate the survival benefit of daratumumab-containing regimens in patients with AL cardiac amyloidosis.

Digital therapeutics (DTx) represent an innovative approach to healthcare, leveraging software applications (apps) delivered through digital devices to treat medical conditions. This review focuses on three DTx apps approved in Japan, targeting nicotine dependence, hypertension, and insomnia. CureApp SC, the DTx system for nicotine dependence, comprises a patient smartphone app, an Internet of Things device for exhaled carbon monoxide measurement, and a Web-based physician app. A clinical trial demonstrated significantly higher rates of continuous abstinence in the intervention group than in the controls (63.9 % vs. 50.5 %, p = 0.001) at 24 weeks, with effects persisting through 52 weeks. For hypertension management, CureApp HT focuses on lifestyle modifications with daily home blood pressure monitoring. The HERB-DH1 trial showed a significant reduction in 24-h systolic blood pressure (between-group difference, -2.4 mmHg; p = 0.024) and morning home blood pressure (between-group difference, -4.3 mmHg; p < 0.001) in the intervention group compared with those in the controls. This hypertension DTx app also exhibits potential lifetime cost-effectiveness. Regarding insomnia management, SUSMED MedCBT-i supports physician-delivered cognitive behavioral therapy for insomnia. In a randomized controlled trial, Athens Insomnia Scale scores significantly improved in the intervention group compared with those in the controls (between-group difference, -3.4 point; p < 0.001) at 8 weeks. These DTx apps represent a significant advancement in managing chronic conditions, offering scalable and accessible methods for delivering evidence-based interventions. They also address the challenges in implementing lifestyle modifications and behavioral therapies in traditional healthcare settings. As DTx become more integrated into routine clinical practice, ongoing research is crucial to evaluate their long-term efficacy, safety, and cost-effectiveness. The success of these initial DTx apps in Japan paves the way for more comprehensive digital health solutions, potentially improving individual patient outcomes and contributing to larger-scale public health improvements in managing chronic conditions.

Tafamidis is used as disease-modifying treatment for patients with wild-type transthyretin cardiac amyloidosis (ATTRwt CA). However, the effects of tafamidis on exercise tolerance are unclear.

Among patients with aortic stenosis, ventricular remodeling by hypertrophy can limit the augmentation of flow with exertion, even after valve intervention. However, the effect of hypertrophy on quality of life (QoL) improvement has not been studied. We aimed to determine the effect of ventricular hypertrophy on QoL outcomes after transcatheter aortic valve replacement (TAVR).

Residual mitral regurgitation (MR) immediately after mitral valve (MV) repair is a risk factor for late reintervention. This study aimed to determine the feasibility of color 3-dimensional intraoperative transesophageal echocardiography (3D-IOTEE) for clarifying the mechanism of residual MR and its impact on the conversion rate to MV replacement (MVR).

This paper aims to review the research progress in repairing injury caused by acute myocardial infarction, focusing on myocardial regeneration, cardiomyocyte apoptosis, and fibrosis. The goal is to investigate the current research trends and challenges in the field of myocardial injury repair.

Diet modification is a mainstay for the successful management of metabolic syndrome and potentially may reduce the risk of cardiovascular disease. Accurate estimation of essential nutrients in daily meals is currently challenging to quantify. HAKARIUM (AstraZeneca Co., Ltd., Osaka, Japan) is a recently introduced artificial intelligence (AI)-based application that can estimate each nutrient component through photographs, although its applicability to real-world practice remains unknown.

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have revolutionized the therapeutic scenario of heart failure, demonstrating favorable effects on mortality and quality of life. Previous studies have yielded conflicting data regarding the effects on ventricular arrhythmias.

Despite strong recommendations in the latest guidelines for implementing guideline-directed medical therapy (GDMT) before discharge, there is a lack of data on the clinical characteristics and outcomes of older patients with heart failure (HF). Therefore, this study aimed to investigate the clinical characteristics and outcomes of patients with HF in a super-aging society during the GDMT era.

The PARALLEL-HF trial showed that treatment with sacubitril/valsartan resulted in more symptomatic hypotension versus enalapril in Japanese patients with heart failure (HF) and reduced ejection fraction, similar to PARADIGM-HF. Use of sacubitril/valsartan in these patients may be limited by concerns regarding hypotension.

An escalation strategy from intra-aortic balloon pump (IABP) to Impella (AbioMed, Danvers, MA, USA) is proposed in patients with cardiogenic shock (CS) refractory to IABP therapy, but its clinical data are lacking. This study aimed to elucidate the clinical characteristics and short-term outcomes in patients undergoing IABP-Impella escalation.

The posterior left atrium (LAPW) is an important substrate for initiation and maintenance of atrial fibrillation (AF). While it has been proposed as a potential target for preventing recurrence of atrial tachyarrhythmias, it remains unclear whether electrical silence of LAPW offers additional benefits over pulmonary vein isolation (PVI) alone. We conducted a systematic review of PubMed, Medline, Embase, and Cochrane databases and identified 21 eligible studies, encompassing 1514 patients assigned to PVI + posterior wall isolation (PWI) group and 1629 patients assigned to PVI group. Over a median follow-up of 12 months, adjunctive PWI significantly improved the atrial tachyarrhythmia-free survival by 14 % in comparison to PVI alone [relative risk (RR): 1.14, 95 % confidence interval (CI): 1.04 to 1.25, p = 0.004]. This improvement was mainly attributed to a pronounced benefit for patients with persistent AF. In addition, patients undergoing PVI + PWI had a longer procedure time [weighted mean difference (WMD): 23.85, 95 % CI: 12.68 to 35.01, p < 0.001], ablation time (WMD: 9.27, 95 % CI: 5.19 to 13.54, p < 0.001), and a nearly negligible increase in fluoroscopic exposure (WMD: 2.69, 95 % CI: -0.23 to 5.62, p = 0.071). There was no increased risk of procedure-related complications between these approaches (RR: 1.06, 95 % CI: 0.71 to 1.57, p = 0.787). Compared with PVI alone, PWI adjunctive to PVI exhibited a higher procedure success of sinus rhythm maintenance in persistent AF during an index catheter ablation. Meanwhile, elongated procedure time and ablation time did not compromise the safety of extensive ablation strategy with additional PWI.

Goreisan, a Japanese herbal medicine, possesses aquaretic properties to regulate body fluid homeostasis and may therefore be effective as a complement to standard therapy in improving outcomes in patients with heart failure (HF).

The region of adipose deposition is an important determinant in the outcomes of patients with heart failure (HF). However, the impact of regional adiposity on HF patients undergoing cardiac resynchronization therapy (CRT) remains unclear.