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A mechanics–based analysis of data from three–dimensional speckle tracking echocardiography is proposed, aimed at investigating deformations in myocardium and at assessing shape and function of distinct strain lines corresponding to the principal strain lines of the cardiac tissue. The analysis is based on the application of a protocol of measurement of the endocardial and epicardial principal strain lines, which was already tested on simulated left ventricles. In contrast with similar studies, it is established that endocardial principal strain lines cannot be identified with any structural fibers, not even along the systolic phase and is suggested that it is due to the capacity of the endocardial surface to contrast the dilation of the left ventricle. A mechanics-based analysis of data from three-dimensional speckle tracking echocardiography is proposed, aimed at investigating deformations in myocardium and at assessing shape and function of distinct strain lines corresponding to the principal strain lines of the cardiac tissue. The analysis is based on the application of a protocol of measurement of the endocardial and epicardial principal strain lines, which was already tested on simulated left ventricles. In contrast with similar studies, it is established that endocardial principal strain lines cannot be identified with any structural fibers, not even along the systolic phase and is suggested that it is due to the capacity of the endocardial surface to contrast the dilation of the left ventricle.

d v w a AORTIC INSUFFICIENCY (AI) in patients after left ventricular assist device (LVAD) implantation is one of the nintended and potentially harmful consequences.1,2 Excessive LVAD flows, resulting in diminished and infrequent aortic valve (AV) opening, may facilitate AI progression and extend its duration to the systolic phase of the cardiac cycle.2,3 The igh temporal resolution of the echocardiographic M mode akes it very effective in monitoring the effects of LVAD speeds n AV function in real time. This case report describes the pathohysiology of AV leaflets akinesis and systolic aortic insufficiency n patients supported with continuous-flow LVAD and shows the rayscale and color M-mode AV surveillance in the perioperative ptimization of the LVAD setting.

The effect of collagen fibers on the mechanics and hemodynamics of a trileaflet aortic valve contained in a rigid aortic root is investigated in a numerical analysis of the systolic phase. Collagen fibers are known to reduce stresses in the leaflets during diastole, but their role during systole has not been investigated in detail yet. It is demonstrated that also during systole these fibers substantially reduce stresses in the leaflets and provide smoother opening and closing. Compared to isotropic leaflets, collagen reinforcement reduces the fluttering motion of the leaflets. Due to the exponential stress-strain behavior of collagen, the fibers have little influence on the initial phase of the valve opening, which occurs at low strains, and therefore have little impact on the transvalvular pressure drop.

The physiological assessment of a lesion is a key to quality of life and prognosis of a patient with moderate coronary stenosis. Blood flow in coronary arteries occurs primarily during diastole, it is evident especially in the LAD. The systolic phase lasts roughly 300 ms and its duration is almost

We report a case of flail mitral valve in an elderly man. Contrast enhanced images of the left ventricle were compared with transthoracic echocardiography. MSCT during systolic phase accurately identified the flail P2 cusp of posterior mitral valve leaflet. It can be performed non-invasively without requiring sophisticated software. Our case suggests that MSCT may have a role in preoperative assessment of coronary arteries and mitral valve apparatus before mitral valve surgery.

Pneumopericardium and hydropneumopericardium are rare conditions in which hemodynamic compromise is common. Loss of the M-mode and two-dimensional image coincident with the systolic phase of each cardiac cycle and swirling echogenic bubbles within the pericardial space produce a distinctive M-mode and two-dimensional echocardiographic appearance. This provides an additional method for prompt diagnosis.