Chikaya Omichi

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In the present study, clinical findings of 15 patients with cardiac sarcoidosis presenting as dilated cardiomyopathy were compared with those of 30 consecutive patients with idiopathic dilated cardiomyopathy. The sarcoidosis patients had different clinical features, including female predominance, a high incidence of grave conduction disturbance and abnormal(More)
A 60-year-old man with a long history of epilepsy was referred for cardiologic evaluation. An earlier diagnosis of epilepsy was made on the basis of his clinical manifestation of tonic-clonic seizure. Electroencephalography (EEG) demonstrated paroxysmal slow waves in response to intermittent photic stimulation. However, electrocardiography (ECG) revealed(More)
In the heart, membrane voltage (Vm) and intracellular Ca (Cai) are bidirectionally coupled, so that ionic membrane currents regulate Cai cycling and Cai affects ionic currents regulating action potential duration (APD). Although Cai reliably and consistently tracks Vm at normal heart rates, it is possible that at very rapid rates, sarcoplasmic reticulum Cai(More)
OBJECTIVES The study examined the activations in the pulmonary veins (PVs) and the vein of Marshall (VOM) during atrial fibrillation (AF) in dogs with congestive heart failure (CHF). BACKGROUND The patterns of activation within the PVs and the VOM during AF in CHF are unclear. METHODS We induced CHF in nine dogs by rapid ventricular pacing. The patterns(More)
It has been suggested from frequency analysis that cardiac fibrillation is driven by stable intramural reentry, with wavebreak occurring due to failure of 1:1 propagation. We tested this hypothesis with a combined experimental and theoretical approach. Optical mapping was performed on epicardial, endocardial, and transmural cut surfaces of fibrillating(More)
INTRODUCTION We previously reported that there is a high incidence of sudden cardiac death (SCD) in dogs with myocardial infarction (MI), complete AV block (CAVB), and nerve growth factor (NGF) infusion to the left stellate ganglion (LSG). Whether or not QT interval prolongation underlines the mechanism of SCD was unclear. METHODS AND RESULTS We analyzed(More)
Whether or not the excitation-contraction (E-C) uncoupler diacetyl monoxime (DAM) and cytochalacin D (Cyto D) alter the ventricular fibrillation (VF) activation patterns is unclear. We recorded single cell action potentials and performed optical mapping in isolated perfused swine right ventricles (RV) at different concentrations of DAM and Cyto D.(More)
UNLABELLED Radiofrequency (RF) catheter ablation of supraventricular tachycardias (SVT) has been shown to result in local parasympathetic denervation. The purpose of this study was to estimate the correlation between RF cumulative energy and parasympathetic denervation at three different ablation sites. METHODS 45 patients who underwent RF ablation of 36(More)
The effects of acute amiodarone infusion on dynamics of ventricular fibrillation (VF) are unclear. Six isolated swine right ventricles (RVs) were studied in vitro. Activation patterns during VF were mapped optically, whereas action potentials were recorded with a glass microelectrode. At baseline, VF was associated with frequent spontaneous wave breaks.(More)