Abnormal left ventricular diastolic filling in chronic thromboembolic pulmonary hypertension: true diastolic dysfunction or left ventricular underfilling?

OBJECTIVES: The purpose of this study was to investigate the cause of abnormal left ventricular (LV) Doppler diastolic filling characteristics in chronic thromboembolic pulmonary hypertension (CTEPH). BACKGROUND: In CTEPH, LV diastolic function often appears abnormal. It is unclear whether this "impaired relaxation" (E相似文献   

Synthetic polymannose as a drug carrier: synthesis,toxicity and anti-fungal activity of polymannose-amphotericin B conjugates

Polymannose (PM) having a weight-average molar mass (M_w) of 30–53 kDa was synthesized by the polycondensation of mannose using phosphorous acid as the catalyst and characterized by various techniques such as NMR, IR, GPC and polarimetry. 2D NMR results confirmed the presence of (1 → 6)-linked α-D-mannose residues as backbone with O-3 and O-2 substituted linear or branched chains in PM. Amphotericin B (AmB) was conjugated to periodate-oxidized PM through Schiff’s linkages at 20 wt% concentration. The AmB-PM conjugates were highly soluble in phosphate buffered saline (180–250 mg/mL), exhibited negligible hemolytic potential to human erythrocytes even at a concentration of 200 μg/mL (equivalent to ~40 μg/mL AmB) and were non-toxic to human embryonic kidney (HEK293T) cells even at a concentration of 250 μg/mL (equivalent to ~50 μg/mL AmB). The minimum inhibitory concentration of the AmB-PM conjugates against C. albicans, C. parapsilosis and C. neoformans was in the range of 0.5–1.0 μg/mL. Mannose receptors are widely expressed on myeloid cells such as macrophages, neutrophils, and dendritic cells. Therefore, apart from treating fungal infections, AmB-PM conjugates also may have therapeutic potential for the treatment of macrophage-associated diseases such as leishmaniasis where mannose receptors are overexpressed.     

Echocardiographic evaluation of iatrogenic atrial septal defect after catheter-based mitral valve clip insertion

The geometries and sizes of persistent iatrogenic atrial septal defects (IASDs) after transseptal puncture during catheter-based mitral valve clip insertion (MVCI) have not been detailed. In this study, 11 IASDs were investigated in 10 patients who underwent MVCI using a guide catheter (24Fr proximally and 22Fr at the atrial septum). The diameters of the long and short axes and the area at maximum and minimum during a cardiac cycle were measured after MVCI using real-time 3-dimensional (RT3D) transesophageal echocardiography (TEE). A circular shape was assumed on 2-dimensional TEE, resulting in an area calculation of π × (dimension/2)(2). The anatomic geometries of IASDs were visualized in a 3-dimensional en face view of the atrial septum. Furthermore, 1 month after MVCI, IASDs were evaluated using echocardiography. The IASDs had a variety of irregular geometries. The mean long-axis diameter was 1.0 ± 0.24 cm, the mean short-axis diameter was 0.51 ± 0.22 cm, and the mean area was 0.40 ± 0.24 cm(2) on RT3D TEE. The diameters and area changed significantly between the maximal and minimal values during the cardiac cycle. Importantly, 2-dimensional TEE underestimated the maximal diameters of IASDs (0.54 ± 0.17 vs 1.0 ± 0.24 cm by RT3D TEE, p <0.01) and the maximal areas of IASDs (0.25 ± 0.15 vs 0.40 ± 0.23 cm(2) by RT3D TEE, p <0.05). One month after MVCI, the smallest and the second smallest IASDs had closed, and the other 9 remained open. In conclusion, RT3D TEE is useful to assess the irregular geometries of IASDs created during MVCI.     

Morphologic features of carcinoid heart disease as assessed by three-dimensional transesophageal echocardiography

Background: Carcinoid heart disease (CHD) is a rare cause of valvular heart disease and carries a poor prognosis. CHD has a unique morphology and echocardiographic features that predominantly involve right‐sided valvular structures. The diagnosis of CHD is usually made by two‐dimensional transthoracic echocardiography (TTE). With the superior spatial resolution of real time three‐dimensional transesophageal echocardiography (3DTEE), structural changes that occur in patients with CHD‐associated valvular heart disease can be examined in greater detail. We undertook this study to examine the incremental value of 3DTEE in the diagnosis of CHD. Methods: A total of four patients with CHD underwent TTE, transesophageal echocardiography (TEE), and 3DTEE as part of their routine clinical evaluation. Results: TTE and TEE for all four patients revealed thickened, fibrosed, retracted, and malcoapted tricuspid leaflets with wide‐open tricuspid valve regurgitation. 3DTEE en face imaging of the tricuspid valve demonstrated the characteristic morphologic features of CHD more clearly in all four patients. Conclusions: 3DTEE provides substantial incremental value over TTE in the assessment of characteristic CHD pathology and thus enhances the echocardiographic diagnosis of CHD. (Echocardiography 2010;27:1098‐1105)     

Comparison between MDCT and Grayscale IVUS in a Quantitative Analysis of Coronary Lumen in Segments with or without Atherosclerotic Plaques

Background

The diagnostic accuracy of 64-slice MDCT in comparison with IVUS has been poorly described and is mainly restricted to reports analyzing segments with documented atherosclerotic plaques.

Objectives

We compared 64-slice multidetector computed tomography (MDCT) with gray scale intravascular ultrasound (IVUS) for the evaluation of coronary lumen dimensions in the context of a comprehensive analysis, including segments with absent or mild disease.

Methods

The 64-slice MDCT was performed within 72 h before the IVUS imaging, which was obtained for at least one coronary, regardless of the presence of luminal stenosis at angiography. A total of 21 patients were included, with 70 imaged vessels (total length 114.6 ± 38.3 mm per patient). A coronary plaque was diagnosed in segments with plaque burden > 40%.

Results

At patient, vessel, and segment levels, average lumen area, minimal lumen area, and minimal lumen diameter were highly correlated between IVUS and 64-slice MDCT (p < 0.01). However, 64-slice MDCT tended to underestimate the lumen size with a relatively wide dispersion of the differences. The comparison between 64-slice MDCT and IVUS lumen measurements was not substantially affected by the presence or absence of an underlying plaque. In addition, 64-slice MDCT showed good global accuracy for the detection of IVUS parameters associated with flow-limiting lesions.

Conclusions

In a comprehensive, multi-territory, and whole-artery analysis, the assessment of coronary lumen by 64-slice MDCT compared with coronary IVUS showed a good overall diagnostic ability, regardless of the presence or absence of underlying atherosclerotic plaques.