Gary Shimizu

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To correlate left ventricular function and histologic features in patients with dilated cardiomyopathy, precise indexes of hemodynamics and semiquantitative histologic data were combined for multivariate analysis. Right endomyocardial biopsy was performed at the time of cardiac catheterization. Five hemodynamic indexes were used for functional assessment:(More)
BACKGROUND Left ventricular (LV) midwall geometry has been described conventionally as the sum of the chamber radius and half of the wall thickness; this convention is based on the assumption of uniform transmural thickening during systole. However, theoretical considerations and experimental data indicate that the inner half (inner shell) of the LV wall(More)
Right ventricular pacing alters left ventricular synchrony and loading conditions, each of which may independently influence left ventricular relaxation. Addition of a properly timed atrial contraction by using sequential atrioventricular (AV) pacing minimizes changes in left ventricular loading conditions, but ventricular asynchrony persists. To separate(More)
Observations that the inner (subendocardial) half of the left ventricular wall contributes more to total left ventricular wall thickening than the outer (subepicardial) half may have important implications in the analysis of myocardial fiber length transients. Accordingly, we measured endocardial and midwall shortening and lengthening rates in normal and(More)
Echocardiographic measurements of the left ventricle were used to define rates of circumferential fiber lengthening at the endocardium and midwall in 12 normal subjects and six patients with concentric left ventricular hypertrophy (wall thickness 11 to 16 mm). There was no difference in chamber size and systolic shortening in the two groups, but peak(More)
The study evaluated substrate cleavage product(s) generated by three botulinum neurotoxin serotype A (BoNT/A) medicinal drug products utilizing a novel and highly specific, light-chain activity, high-performance liquid chromatography (LCA-HPLC) method. Samples were reacted with a commercially available BoNT/A fluorescent substrate derived from the SNAP-25(More)
Left ventricular (LV) function was evaluated in 32 patients with dilated cardiomyopathy (DC) who underwent cardiac catheterization during the past 6 years (group 4), and the results were compared with the data of 30 normal subjects (group 1). The patients were divided into mildly (group 2, 12 patients) and severely symptomatic subgroups (group 3, 20(More)
OBJECTIVE To examine the basis for local wall motion abnormalities commonly seen in patients with ischemic heart disease, computer-controlled isolated muscle studies were carried out. METHODS Force patterns of physiologically sequenced contractions (PSCs) from rat left ventricular muscle preparations under well-oxygenated conditions and during periods of(More)
A precise assessment of left ventricular function was performed in 20 patients with hypertrophic nonobstructive cardiomyopathy to elucidate the basic pathophysiology, and the data were compared with those in 22 normal subjects. Whereas end-diastolic pressure was high in those with cardiomyopathy, a more accurate index of preload, end-diastolic stress, did(More)