Publications by authors named "Kentaro Ozu"

Unlabelled: New cardiac implantable electronic devices (CIEDs), such as leadless pacemakers and subcutaneous implantable cardioverter defibrillators (S-ICDs), are being used in patients with adult congenital heart disease. The selection of CIEDs often requires careful consideration due to technical challenges posed by a unique heart structure. A 27-year-old man following a surgical tetralogy of Fallot (TOF) repair developed non-sustained ventricular tachycardia, sick sinus syndrome, and complete atrioventricular block.

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  • Atrial cardiomyopathy (AtCM) is gaining attention for its association with serious cardiovascular issues like atrial tachyarrhythmia and strokes, but little is known about its long-term effects since it's a relatively new concept.
  • A case study of a 78-year-old man revealed he had end-stage AtCM, diagnosed after decades of battling atrial fibrillation and several related complications, including cardiogenic embolism and ineffective heart ablation treatments.
  • Despite ongoing treatment, the patient faced worsening symptoms and complications, emphasizing the importance of monitoring and managing the progression of AtCM.
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  • The study investigates how changes in pacing cycle length (PCL) affect the electrical properties of the left atrium during atrial fibrillation ablation, using a high-resolution mapping system.
  • Atrial mapping was conducted on 48 patients, revealing that a shorter PCL (300 ms) increased the low-voltage area (LVA) and prolonged activation time, suggesting significant shifts in electrical activity.
  • The findings highlight the importance of considering PCL-dependent changes when evaluating LVA and slow conduction areas as potential substrates for atrial fibrillation, indicating their assessments may not be fully valid without this context.
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An 87-year-old man developed delayed cardiac tamponade 55 min after leadless pacemaker implantation and recurrent pericardial effusion 20 days later. Electrocardiogram-gated enhanced cardiac computed tomography revealed that the leadless pacemaker tines on the lateral side had penetrated the right ventricular free wall. He underwent off-pump hemostatic surgery.

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Background: The clinical significance of left atrial local electrogram fractionation after restoration of sinus rhythm in patients with atrial fibrillation (AF) has not been elucidated.

Methods: We evaluated ultrahigh-resolution maps of the left atrium (LA) during RA pacing acquired after pulmonary vein isolation in 40 patients with AF. The association between low-voltage area (LVA, <0.

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Introduction: Persistent left superior vena cava (PLSVC) is one of the major sources of triggers and drivers of atrial fibrillation (AF). There has been no established PLSVC ablation procedure to eliminate the arrhythmogenicity along the entire length of PLSVC.

Methods And Results: A 70-year-old woman with a history of two previous catheter ablations for AF, mitral valvuloplasty, and an unroofed coronary sinus-type atrial septal defect closure underwent the redo AF ablations.

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  • There has been observed electromagnetic interference (EMI) between implantable left ventricular assist devices and cardiac implantable electronic devices.
  • A new case highlighted EMI between a percutaneous ventricular assist device and an implantable cardioverter-defibrillator, confirmed through ex vivo simulation testing.
  • The level of EMI might vary based on the distance between the two types of devices.
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Biatrial tachycardia via Bachmann's bundle, interatrial septum, and left atrial anterior wall can be treated by left atrial anterolateral linear ablation without left atrial appendage isolation, even under mitral isthmus block.

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• Intra-isthmus reentry is a variant of cavotricuspid isthmus-dependent atrial flutter. • Intra-isthmus reentry circuit can involve the rotational activation around the coronary sinus ostium. • Ultrahigh-resolution mapping can help delineate the complete intra-isthmus reentry circuit.

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  • - Nifekalant effectively reduced intra-superior vena cava fibrillation.
  • - This type of fibrillation complicated the assessment of superior vena cava isolation.
  • - The success of Nifekalant in this context highlights its potential in managing specific cardiac rhythms during medical evaluations.
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Subcutaneous implantable cardioverter-defibrillators (S-ICDs) are susceptible to T-wave oversensing (TWOS) caused by high rate-dependent QRS-T morphology changes. We experienced an inappropriate S-ICD shock due to TWOS, which could not be predicted by routine exercise testing. A newly available high-pass filter might be effective for avoiding this.

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Pulmonary arterial hypertension (PAH) is known to develop as a consequence of multiple genetic and/or non-genetic factors. A 27-year-old woman with chronic hepatitis C virus (HCV) infection developed severe PAH after interferon (IFN) therapy. Although most of the reported clinical courses of IFN-induced PAH are poor despite the discontinuation of IFN, the present patient was successfully treated with a triple combination therapy.

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Pheochromocytoma crisis is a feared and potentially lethal complication associated with excess release of catecholamine from the tumor, which might lead to multiple organ failure (MOF). The definitive treatment for pheochromocytoma is surgical resection. To safely proceed with surgery, hemodynamic stabilization in the acute phase is indispensable, but it might be extremely challenging in case of pheochromocytoma crisis with MOF even if the sufficient pharmacological drugs would be administered.

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Background: Identification of patients with chronic heart failure (CHF) at a risk for sudden cardiac death (SCD) is an important objective. Early repolarization pattern (ERP) is associated with ventricular fibrillation in patients without structural heart diseases. Moreover, ERP was reported to be associated with SCD in patients with old myocardial infarction in a case-control study.

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