Deterioration of cardiac contractility during congestive heart failure (CHF) is believed to involve decreased function of individual cardiomyocytes and may include reductions in contraction magnitude and/or kinetics. We examined the progression of in vivo and in vitro alterations in contractile function in CHF mice and investigated underlying alterations in Ca(2+) homeostasis. Following inducti...

Clinical assessment of myocardial ischemia based on visually-assessed wall motion scoring from echocardiography is semiquantitative, operator dependent, and heavily weighted by operator experience and expertise. Cardiac motion estimation methods such as tissue Doppler imaging, used to assess myocardial muscle velocity, provides quantitative parameters such as the strain-rate and strain derived ...

A TFEPI-CSPAMM sequence is introduced, which is optimized with respect to acquisition speed and image quality. The sequence is used in a stress study, where a short breath-hold duration is crucial, and tested for reproducibility of deformation parameters extracted by HARP for repeated measurements.

A beagle dog treated with saline as a control animal in a preclinical study was euthanized due to sudden systemic deterioration. On histopathological examination, contraction band necrosis of myocardial cells was observed widely in the left ventricular wall, including the papillary muscle and apex, and observed slightly in the ventricular septum and left atrium. In the brain, necrosis was obser...

Myocardial stunning and hibernation have been subjects of intense laboratory and clinical investigations to elucidate mechanisms responsible for contractile dysfunction after transient ischemia or chronic hypoperfusion. Considerable evidence has implicated the generation of oxygen-derived free radicals and derangements in myocardial energy metabolism and excitation-contraction coupling as major...

SUMMARY Although the circulatory changes in various thyroid states are well known, the alterations of myocardial contractility of hypothyroidism and hyperthyroidism have remained controversial. The changes in the length of the ejection time (ET) and isovolumic contraction time (ICT) are used as indicative of alterations in inotropic state of the myocardium. Isovolumic contraction time, ejection...