Kazunori Moritani

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Left atrial function was evaluated in patients with and without remote myocardial infarction. The simultaneous left atrial pressure recording and left atrial and left ventricular cineangiograms were obtained with a catheter-tip micromanometer. The pressure-volume curve of the left atrium was composed of an A-loop and a V-loop. The ratio of active atrial(More)
We tested whether acute pressure overloading of the left ventricle (LV) had spatially different effects on repolarization, thereby causing arrhythmias. The effects of gadolinium (Gd3+), a nonspecific blocker of stretch-activated channels were also examined. In anesthetized dogs, 5 s clamping of the ascending aorta (AC), separated by 5-min intervals, was(More)
The effects of the activation sequence on ventricular repolarization and its spatial gradient were examined in anesthetized open-chest dogs. Unipolar and bipolar electrograms were recorded from 47 epicardial sites on the anterior left ventricular wall using a mapping electrode. The local QT interval (QT) and the activation time (AT) at each site were(More)
We examined the responses of epicardial (Epi) and endocardial (Endo) layers to ATP-sensitive K+ (KATP) channel modulators during regional ischemia in anesthetized dogs. Five-minute occlusion of the left anterior descending coronary artery was repeated at 30-min interval. Monophasic action potentials (MAPs) and extracellular K+ concentrations ([K+]o) were(More)
We tested 5-hydroxydecanoate (5-HD), a specific blocker of ATP-sensitive potassium channels (IK.ATP), to determine if it mitigates electrophysiologic changes produced by regional myocardial ischemiain vivo. A sequence of 5-minute occlusion of the distal LAD and 30-minute reperfusion was repeated while recording the monophasic action potential (MAP) and(More)
Relations between left atrial contraction and left atrial early filling were studied in eight subjects with atypical chest pain from simultaneous left atrial pressure recordings and left atrial cineangiograms. The left atrial ejection phase was defined as the interval from the onset of the sharp systolic rise in left atrial pressure (a point) to the point(More)
Left atrial function in patients with hypertensive heart disease was compared with that in control subjects. In patients with hypertensive heart disease, the time constant of left ventricular relaxation was significantly greater than that in controls (54 +/- 18 vs 31 +/- 16 msec; p less than 0.01). The ratio of left ventricular filling volume before atrial(More)
This study observed the left function in determining filling dynamics of the left ventricle in patients with myocardial infarction. The study consisted of eight control subjects and ten patients with myocardial infarction. The left ventricular filling volume is considered to be composed of the left atrial passive emptying, active emptying, and conduit(More)
BACKGROUND Plasma brain natriuretic peptide (BNP) levels are useful marker to guide medical treatment in patients with congestive heart failure (CHF). We tested the hypothesis that the plasma BNP concentration would be a useful marker of beta-blocker therapy for CHF. METHODS AND RESULTS Eighty-four patients with New York Heart Association class II-IV CHF(More)
Coronary angiography of both right and left coronary arteries, using the Sones technique, was performed during the attack of total spastic obstruction in 11 patients with clinically documented history of variant angina. None of the patients had more than 70% stenosis of organic atherosclerosis in any coronary artery and none had a history of myocardial(More)