Sandor Kovacs

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OBJECTIVES We determined whether caloric restriction (CR) has cardiac-specific effects that attenuate the established aging-associated impairments in diastolic function (DF). BACKGROUND Caloric restriction retards the aging process in small mammals; however, no information is available on the effects of long-term CR on human aging. In healthy individuals,(More)
The duration of diastole can be defined in terms of mechanical events. Mechanical diastolic duration (MDD) is comprised by the phases of early rapid filling (E wave), diastasis, and late atrial filling (A wave). The effect of heart rate (HR) on diastolic duration is predictable from kinematic modeling and known cellular physiology. To determine the(More)
Effects of regional diastolic pressure differences within the left ventricle on the measured transmitral pressure-flow relation were determined by simultaneous micromanometric left atrial (LAP) and left ventricular pressure (LVP) measurements, and Doppler echocardiograms in 11 anesthetized, closed-chest dogs. Intraventricular pressure recordings at sites(More)
A new parametrized diastolic filling (PDF) formalism for evaluation of holodiastolic (left and right) ventricular function via Doppler echocardiography is presented. It is motivated by the empiric observation that during diastole the heart behaves as a suction pump whose dynamics, in certain respects, are those of a damped harmonic oscillator. An expression(More)
Modeling methods have been employed to further characterize the physical and physiologic processes of filling and diastolic function. They have led to more detailed understanding of the effect of alteration of physiologic parameters on the Doppler E-wave contour as well as pulmonary vein flow. Depending on the modeling approach, different aspects of the(More)
The ability of a blood pool contrast agent to enhance MR coronary angiography was defined. The proximal coronary vessels of pigs were imaged before and after administration of Gd-DTPA bound covalently to bovine serum albumin (0.2 mmol/ kg). The contrast agent resulted in a reduction of the blood T1 value to 33+/-5 msec, as determined in vivo with a(More)
BACKGROUND Heart failure with preserved ejection fraction (HFPEF) involves failure of cardiovascular reserve in multiple domains. In HFPEF animal models, dietary sodium restriction improves ventricular and vascular stiffness and function. We hypothesized that the sodium-restricted dietary approaches to stop hypertension diet (DASH/SRD) would improve left(More)
Themain purpose of this note is to present a characterization of rational singularities in characteristic 0. The essence of the characterization is that it is enough to require less than the usual definition. Theorem 1. Let φ : Y → X be a morphism of varieties over C, and let ρ : X → Rφ∗ Y be the associated natural morphism. Assume that Y has rational(More)
PURPOSE To evaluate the single-incision technique for the placement of subcutaneous chest ports. Advantages, technical success, and complications were assessed. MATERIALS AND METHODS From March 2007 through May 2008, 161 consecutive chest ports were placed with a modified single-incision technique and sonographic and fluoroscopic guidance via the right(More)