Validation of methods for effective orifice area measurement of prosthetic valves by two-dimensional and Doppler echocardiography following transcatheter self-expanding aortic valve implantation.

BACKGROUND: The effective orifice area (EOA) is utilized to characterize the hemodynamic performance of the transcatheter heart valve (THV). However, there is no consensus on EOA measurement of self-expanding THV. We aimed to compare two echocardiographic methods for EOA measurement following transcatheter self-expanding aortic valve implantation. METHODS: EOA was calculated according to the continuity equation. Two methods were constructed. In Method 1 and Method 2, the left ventricular outflow tract diameter (LVOTd) was measured at the entry of the prosthesis (from trailing-to-leading edge) and proximal to the prosthetic valve leaflets (from trailing-to- leading edge), respectively. The velocity-time integral (VTI) of the LVOT (VTILVOT) was recorded by pulsed-wave Doppler (PW) from apical windows. The region of the PW sampling should match that of the LVOTd measurement with precise localization. The mean transvalvular pressure gradient (MG) and VTI of THV was measured by Continuous wave Doppler. RESULTS: A total of 113 consecutive patients were recruited. The mean age was 77.2 ± 5.5 years, and 72 patients (63.7%) were male. EOA1 with the use of Method 1 was larger than EOA2 (1.56 ± 0.39 cm2 vs. 1.48 ± 0.41 cm2, P = 0.001). MG correlated better with the indexed EOA1 (EOAI1) (r = -0.701, P < 0.001) than EOAI2 (r = -0.645, P < 0.001). According to EOAI (EOAI ≤ 0.65 cm2/m2, respectively), the proportion of sever prosthesis-patient mismatch with the use of EOA1 was lower than EOA2 (12.4% vs. 21.2%, P < 0.05). Compared with EOA2, EOA1 had lower interobserver and intra-observer variability (intra: 0.5% ± 17% vs. 3.8% ± 22%, P < 0.001; inter: 1.0% ± 9% vs. 3.5% ± 11%, P < 0.001). CONCLUSIONS: For transcatheter self-expanding valve EOA measurement, LVOTd should be measured in the entry of the prosthesis stent (from trailing-to-leading edge), and VTILVOT should match that of the LVOTd measurement with precise localization.

Assessment of the morphology and mechanical function of the left atrial appendage by real-time three-dimensional transesophageal echocardiography.

BACKGROUND: The left atrial appendage (LAA) is an important source of thrombus formation. We investigated the feasibility of the recently developed real-time three-dimensional transesophageal echocardiography (RT3D-TEE) method in assessment of the morphology and function of the LAA. METHODS: Ninety-six consecutive patients (58 males with a mean age of (43.4 ± 12.5) years) who were referred for 2-dimensional (2D) transesophageal echocardiography (TEE) underwent additional RT3D-TEE. LAA morphology was visualized in multiple views. Orifice size, depth, volumes and ejection fraction (EF) of the LAA, were measured. RESULTS: All the patients underwent RT3D-TEE examination without complications. Ninety-two patients (95.8%) had adequate images for visualization and quantitative analysis of the LAA. The LAA exhibited great variability with respect to relative dimensions and morphology. LAA orifice area was (3.8 ± 1.2) cm(2) with a diameter of (2.4 ± 0.9) cm × (1.4 ± 0.6) cm. The mean depth of the LAA was (2.9 ± 0.7) cm. End-diastolic volume (EDV-LAA), end-systolic volume (ESV-LAA) and EF of the LAA were (6.2 ± 3.7) ml, (4.1 ± 2.8) ml, and 0.35 ± 0.16, respectively. EDV-LAA, ESV-LAA and the orifice area of the LAA in patients with atrial fibrillation (AF) were larger than those without AF, whereas the EF was smaller in the AF patients. CONCLUSIONS: Defining LAA morphology and quantitative analysis of the size and function of the LAA with superior quality and resolution of images using RT3D-TEE is feasible. This technique may be an ideal tool for guidance of the LAA occlusion procedure. Determination of LAA volumes and volume-derived EF by RT3D-TEE provides new insights into the analysis of LAA function.

Relative Factors of Glucose Metabolism Disorders in Newborn Infants / 实用儿科临床杂志

Objective To investigate the relative risk factors of glucose metabolism disorder in newborn infants.Methods Clinical information of 791 newborns suffered from glucose metabolism disorders who had been hospitalized in NICU from Jan.2004 to May 2007 were analyzed retrospectively.Four hundred and thirty-nine cases presented with hypoglycemia,275 cases presented with hyperglycemia,and 77 cases presented with both hypoglycemia and hyperglycemia.Data of risk factors were processed with both ?2 test and multiple Logistic regression analysis.Results The statistic analysis showed that low birth weight[258 cases(58.77%)],asphyxia[217 cases(49.43%)],acidosis[146 cases(33.26%)],hypothermia[128 cases(29.16%)],maternal gestational hypertension[83 cases(18.91%)],pneumonia[63 cases(14.35%)],anomaly of placenta[35 cases(7.97%)],maternal diabetes[17 cases(3.87%)] and septicaemia[10 cases(2.28%)]were significant hypoglycemia risk factors(according to the level of morbidity).Pneumonia[98 cases(35.64%)],asphyxia[129 cases(27.23%)],hypoxemia[61 cases(22.18%)]and septicaemia[24 cases(8.73%)]were significant hyperglycemia risk factors.Acidosis[33 cases(42.86%)],pneumonia[27 cases(35.06%)]and maternal diabetes[6 cases(7.79%)] were significant risk factors for neonates with both hypoglycemia and hyperglycemia.Conclusion Dynamic monitoring of blood glucose concentration and reasonable adjustment is recommended for neonates with risk factors to lower morbility and mortality.