Circulation. Cardiovascular imaging
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Circ Cardiovasc Imaging · Sep 2011
Comparative StudyEvaluation of the left atrial appendage with real-time 3-dimensional transesophageal echocardiography: implications for catheter-based left atrial appendage closure.
Precise knowledge of left atrial appendage (LAA) orifice size is crucial for correct sizing of LAA closure devices. The aim of the present study was to determine the performance of real-time 3D transesophageal echocardiography (RT3DTEE) for LAA orifice size assessment, compared with 2D transesophageal echocardiography (2DTEE), and to investigate the impact of atrial fibrillation (AF) on LAA orifice size. ⋯ RT3DTEE is more accurate than 2DTEE for the assessment of LAA orifice size. A progressive increase in LAA orifice area is observed with increasing frequency of AF.
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Circ Cardiovasc Imaging · Sep 2011
Comparative StudyEchocardiographic indices do not reliably track changes in left-sided filling pressure in healthy subjects or patients with heart failure with preserved ejection fraction.
In select patient populations, Doppler echocardiographic indices may be used to estimate left-sided filling pressures. It is not known, however, whether changes in these indices track changes in left-sided filling pressures within individual healthy subjects or patients with heart failure with preserved ejection fraction (HFpEF). This knowledge is important because it would support, or refute, the serial use of these indices to estimate changes in filling pressures associated with the titration of medical therapy in patients with heart failure. ⋯ Within individual subjects the noninvasive indices E/e' and E/Vp do not reliably track changes in left-sided filling pressures as these pressures vary, precluding the use of these techniques in research studies with healthy volunteers or the titration of medical therapy in patients with HFpEF.
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Circ Cardiovasc Imaging · Sep 2011
Comparative StudyDual manganese-enhanced and delayed gadolinium-enhanced MRI detects myocardial border zone injury in a pig ischemia-reperfusion model.
Gadolinium (Gd)-based delayed-enhancement MRI (DEMRI) identifies nonviable myocardium but is nonspecific and may overestimate nonviable territory. Manganese (Mn(2+))-enhanced MRI (MEMRI) denotes specific Mn(2+) uptake into viable cardiomyocytes. We performed a dual-contrast myocardial assessment in a porcine ischemia-reperfusion (IR) model to test the hypothesis that combined DEMRI and MEMRI identifies viable infarct border zone (BZ) myocardium in vivo. ⋯ The dual-contrast MEMRI-DEMRI detects BZ viability within DEMRI infarct zones. This approach may identify injured, at-risk myocardium in ischemic cardiomyopathy.
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Circ Cardiovasc Imaging · Jul 2011
Mechanisms of acute mitral regurgitation in patients with takotsubo cardiomyopathy: an echocardiographic study.
Recent studies have suggested acute mitral regurgitation (MR) as a potentially serious complication of takotsubo cardiomyopathy (TTC); however, the mechanism of acute MR in TTC remains unclear. The aim of this study was to elucidate the mechanisms of acute MR in patients with TTC. ⋯ SAM and tethering of the mitral valve are independent mechanisms with differing pathophysiology that can lead to acute MR in patients with TTC.