Imaging and quantifying valvular heart disease using magnetic resonance techniques.

Echocardiography remains the cornerstone of noninvasive valvular heart disease evaluation. There are instances where MRI can be of use. Aside from the obvious advantage where limited acoustic windows are present, cardiac magnetic resonance (CMR) allows for imaging in any desired plane, and advantage can be taken of the ability to align with any regurgitant or stenotic flow jet.

Immune activation is associated with reduced skeletal muscle mass and physical function in chronic heart failure.

Background: Chronic heart failure is characterized by immune activation and increased circulating levels of cytokines. Whether humoral factors contribute to the peripheral manifestations of the heart failure syndrome, such as muscle atrophy and reduced physical work capacity, however, is not clear.

Methods: We measured circulating cytokines (tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6)), their soluble receptors (sTNF-alpha RII, IL-6sR), markers of immune activation (C-reactive protein (CRP)), muscle mass, aerobic capacity and muscle strength in 10 patients with heart failure (mean +/- S.

Resistance training increases total daily energy expenditure in disabled older women with coronary heart disease.

Physical activity energy expenditure (PAEE) is a determinant of prognosis and fitness in older patients with coronary heart disease (CHD). PAEE and total energy expenditure (TEE) are closely related to fatness, physical function, and metabolic risk in older individuals. The goal of this study was to assess effects of resistance training on PAEE, TEE, and fitness in older women with chronic CHD and physical activity limitations (N = 51, mean age: 72 + 5 yr).

Regional differences in the force-frequency relation of human left ventricular myocardium in mitral regurgitation: implications for ventricular shape.

Sphericalization of the left ventricular (LV) chamber shape in patients with mitral regurgitation (MR) contributes to increased LV wall stress and energy consumption. On the basis of previous observations, we hypothesized the existence of regional differences in the force-frequency relation (FFR) within the LV that may contribute to its shape. Accordingly, in the present study, we assessed regional variation in the FFR in patients undergoing surgery for chronic, nonischemic MR with class II-III heart failure symptoms and related our findings to the in vivo LV shape.

Skeletal muscle myofibrillar protein metabolism in heart failure: relationship to immune activation and functional capacity.

Chronic heart failure is characterized by changes in skeletal muscle that contribute to physical disability. Most studies to date have investigated defects in skeletal muscle oxidative capacity. In contrast, less is known about how heart failure affects myofibrillar protein metabolism.

Development of whole-body and skeletal muscle insulin resistance after one day of hindlimb suspension.

Hindlimb suspension (HS) of rats is a model of simulated weightlessness and induces dynamic alterations in insulin action. In the present study, the effect of acute (1-day) HS on whole-body glucose tolerance and insulin action on skeletal muscle glucose transport was assessed in juvenile, female Sprague-Dawley rats. Compared to weight-bearing control rats, 1-day HS animals displayed significantly decreased glucose tolerance and diminished whole-body insulin sensitivity.

Enhanced insulin action on glucose transport and insulin signaling in 7-day unweighted rat soleus muscle.

Hindlimb suspension (HS), a model of simulated weightlessness, enhances insulin action on glucose transport in unweighted rat soleus muscle. In the present study, we tested the hypothesis that these changes in glucose transport in 3- and 7-day HS soleus of juvenile, female Sprague-Dawley rats were due to increased functionality of insulin signaling factors, including insulin receptor (IR), IR substrate-1 (IRS-1), phosphatidylinositol 3-kinase (PI3-kinase), and Akt. Insulin-stimulated (2 mU/ml) glucose transport was significantly (P < 0.

Left ventricular systolic torsion and exercise in normal hearts.

This study examines the use of a novel 2-dimensional echocardiographic technique to measure left ventricular (LV) systolic torsion or twist in normal human hearts during maximal exercise. The effects of dynamic exercise on LV twist have not previously been determined. LV twist was measured in 25 healthy human control patients before and after maximal treadmill exercise.

Management of Mitral Regurgitation Due to Mitral Prolapse.

Notable advances have been made in the treatment of mitral regurgitation, especially the advances resulting from prolapse of the mitral valve with or without a flail leaflet. Prosthetic mitral valve replacement results in a high incidence of postoperative left ventricular systolic dysfunction. Recognition of the importance of the subvalvular apparatus for preserving contractile function has fostered development of new repair techniques that preserve native valve tissue and reduce or eliminate postoperative systolic dysfunction and the need for anticoagulation.

Differential half-maximal effects of human insulin and its analogs for in situ glucose transport and protein synthesis in rat soleus muscle.

Analogs of human insulin have been used to discriminate between responses of metabolic and mitogenic (growth-related) pathways. This study compared the stimulatory effects of human insulin (HI) and 2 analogs (X2, B-Asp(9), B-Glu(27) and H2, A-His(8),B-His(4),B-Glu(10), B-His(27)) on glucose uptake and protein synthesis in rat soleus muscle in situ. Glucose uptake, estimated by intramuscular (IM) injection of 2-deoxy[1,2-3H]glucose with or without insulin, was maximally increased at 10(-6) mol/L for HI and X2 and 10(-7) mol/L for H2.

Effects of resistance training on physical function in older disabled women with coronary heart disease.

We studied whether disabled older women with coronary heart disease can perform resistance training at an intensity sufficient to improve measured and self-reported physical function [n = 30, 70.6 +/- 4.5 (SD) yr].

Determinants of disability in older coronary patients.

Background: Patient-reported physical function is a major component of disability determinations and an important contributor to health-related quality of life. Prior studies of coronary disability have shown a surprisingly poor correlation between real-life activity profile and exercise capacity measured on the treadmill. The goal of the current investigation was to evaluate the relative importance of medical factors, sex, fitness-related measures, and psychologic factors as determinants of patient-reported physical function score in older persons with established coronary heart disease (CHD).

Echocardiographic Assessment of Dynamic Changes in Left Ventricular Shape.

Changes in resting left ventricular shape have been related to underlying left ventricular dysfunction and may precede detectable hemodynamic abnormalities. The significance of dynamic changes in left ventricular shape has only recently been examined. In patients with systolic left ventricular dysfunction, dynamic changes in heart shape correlate strongly with exercise duration.