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81.
The clinical value of the estimation of systolic pulmonary artery pressure, based on Doppler assessment of peak tricuspid regurgitant velocity using transoesophageal echocardiography, is unclear. We studied 109 patients to evaluate the feasibility of obtaining adequate Doppler recordings, and compared Doppler estimates with values measured using a pulmonary artery catheter in a subset of 33 patients. Tricuspid regurgitation was evaluated at the mid‐oesophageal level at 0–120° using Doppler echocardiography. A Doppler signal was defined as adequate if there was a ≤ 20° alignment and a full envelope. Doppler estimates of systolic pulmonary artery pressure within 10 mmHg and 15% of the value recorded with the pulmonary artery catheter were considered to be in sufficient agreement. Adequate Doppler signals were obtained in 64/109 (59%) patients before and 54/103 (52%) after surgery. Doppler estimates by transoesophageal echocardiography were within 10 mmHg and 15% of values recorded with the pulmonary artery catheter in 28/33 (75%) patients and 22/31 (55%) patients, respectively. In 7 (21%) patients, the echocardiographic Doppler measurement exceeded the measured systolic pulmonary artery pressure by more than 30%. Our study indicates that estimation of the systolic pulmonary artery pressure using transoesophageal Doppler echocardiography is not a reliable and clinically useful method in anaesthetised patients undergoing mechanical ventilation.  相似文献   
82.
While belatacept has shown favorable short‐ and midterm results in kidney transplant recipients, only projections exist regarding its potential impact on long‐term outcome. Therefore, we performed a retrospective case‐match analysis of the 14 belatacept patients originally enrolled in the phase II multicenter trial at our center. Fifty six cyclosporine (CyA)‐treated patients were matched according to age at transplantation, first/retransplant, and donor type. Ten years after kidney transplantation, kidney function remained superior in belatacept‐treated patients compared with the CyA control group. Moreover, none of the belatacept‐treated patients had donor‐specific antibodies ≥10 years post‐transplantation compared with 38.5% of tested CyA‐treated subject (0/10 vs. 5/13; P = 0.045). Notably, however, patient and graft survival was virtually identical in both groups (71.4% vs. 71.3%; P = 0.976). In the present single‐center study population, patients treated with belatacept demonstrated a patient and graft survival at 10 years post‐transplant which was comparable to that of similarly selected CNI‐treated patients. Larger studies with sufficient statistical power are necessary to definitively determine long‐term graft survival with belatacept.  相似文献   
83.

Objective

Increasing evidence doubts the benign nature of metabolically healthy obesity (MHO). An investigation of the association of MHO and other obesity phenotypes with electrocardiographic left ventricular hypertrophy (ECG-LVH), a risk factor for cardiovascular disease (CVD), can give insight into the pathophysiological basis for increased risk of CVD linked to these phenotypes.

Methods

This analysis included 3997 participants (58.7?±?13.6?years; 51.8% women) without CVD from the NHANES-III. Metabolic syndrome was defined according to the Adult Treatment Panel III. Obesity was defined as body mass index ≥30?kg/m2. Multivariable logistic regression was used to examine the cross-sectional association between 4 obesity phenotypes (metabolically healthy non-obese (MHNO) (reference), metabolically unhealthy non-obese (MUNO), MHO and metabolically unhealthy obese (MUO) with Cornell voltage ECG-LVH.

Results

There was an incremental increase in the prevalence of ECG-LVH across obesity phenotypes with the highest prevalence in the MUO followed by MHO, MUNO and then MHNO (ECG-LVH?=?6.45%, 5%, 4.71%, and 1.69%, respectively, trend p-value?<?0.001). Also, there was incremental increase in the strength of associations with ECG-LVH across obesity phenotypes with higher odds of ECG-LVH in the MUO (OR (95% CI): 4.12 (2.30–7.39) followed by MUNO (OR (95% CI): 2.62 (1.45–4.73) then MHO (OR (95% CI): 2.45 (1.11–5.43) compared to MHNO. The MHO association with ECG-LVH was stronger in men than women (OR (95% CI): 5.55 (1.49–20.70) vs. 1.94 (0.71–5.24) respectively; interaction p-value?=?0.04).

Conclusions

Obesity phenotypes including MHO are associated with ECG-LVH, thus further questioning the concept of benign obesity.  相似文献   
84.
ObjectivesThis study aimed to validate a dedicated software for quantitative videodensitometric angiographic assessment of mitral regurgitation (QMR).BackgroundQuantitative videodensitometric aortography of aortic regurgitation using the time-density principle is a well-documented technique, but the angiographic assessment of mitral regurgitation (MR) remains at best semi-quantitative and operator dependent.MethodsFourteen sheep underwent surgical mitral valve replacement using 2 different prostheses. Pre-sacrifice left ventriculograms were used to assess MR fraction (MRF) using QMR and MR volume (MRV). In an independent core lab, the CAAS QMR 0.1 was used for QMR analysis. In vitro MRF and MRV were assessed in a mock circulation at a comparable cardiac output to the in vivo one by thermodilution. The correlations and agreements of in vitro and in vivo MRF, MRV, and interobserver reproducibility for QMR analysis were assessed using the averaged cardiac cycles (CCs).ResultsIn vivo derived MRF by QMR strongly correlated with in vitro derived MRF, regardless of the number of the CCs analyzed (best correlation: 3 CCs y = 0.446 + 0.994x; R = 0.784; p =0.002). The mean absolute difference between in vitro derived MRF and in vivo derived MRF from 3 CCs was 0.01 ± 4.2% on Bland-Altman analysis. In vitro MRV and in vivo MRV from 3 CCs were very strongly correlated (y = 0.196 + 1.255x; R = 0.839; p < 0.001). The mean absolute difference between in vitro MRV and in vivo MRV from 3 CCs was –1.4 ± 1.9 ml. There were very strong correlations of in vivo MRF between 2 independent analysts, regardless of the number of the CCs.ConclusionsIn vivo MRF using the novel software is feasible, accurate, and highly reproducible. These promising results have led us to initiate the first human feasibility study comprising patients undergoing percutaneous mitral valve edge-to-edge repair.  相似文献   
85.

Background

Patch electrocardiographic (ECG) monitors permit extended noninvasive ambulatory monitoring. To guide use of these devices, information is needed about their performance. We sought to determine in a large general population sample the acceptability of patch ECG monitors, the yield of arrhythmia detection, and the consistency of findings in participants monitored twice.

Methods

In the Multi-Ethnic Study of Atherosclerosis, 1122 participants completed one or two monitoring episodes using the Zio Patch XT, a single-channel ECG patch monitor capable of recording for 14?days. Recordings were analyzed for atrial fibrillation (AF), atrial flutter, atrioventricular block, pauses, and supraventricular and ventricular ectopy.

Results

The mean(SD) age at the time of monitoring was 75(8) years, 52% were men, and 15% had a prior history of clinically-recognized AF/flutter. The median monitoring duration was 13.8?days. Among 804 participants with no prior clinical history of AF/flutter and at least 12?days of monitoring on a single device, AF/flutter was detected in 32 (4.0%); in 38% of these, AF/flutter was first detected during days 3 through 12 of monitoring. In participants monitored twice, findings from the two devices showed excellent agreement for supraventricular and ventricular ectopic beats per hour, but only fair agreement for high-grade atrioventricular block and pauses of >3?s duration.

Conclusions

In a general population of older individuals, new diagnoses of AF/flutter were made in 4.0% of participants without a prior history. A single monitoring episode accurately estimated rates of supraventricular and ventricular ectopy.  相似文献   
86.
[Purpose] This study investigated the intra-rater, inter-rater and test-retest reliability of the sideways step test (SST), its correlation with other indicators of stroke-specific impairment, and the cut-off count best discriminating subjects with stroke from their healthy counterparts. [Subjects and Methods] Forty-three subjects with chronic stroke and 41 healthy subjects older than 50 years participated in this study. The SST was administered along with the Fugl-Meyer motor assessment for the lower extremities (FMA-LE), the five-times sit to stand (5TSTS) test, the Berg Balance Scale (BBS), the movement velocity (MVL) by the limits of stability (LOS) test, the ten-metre walk (10mW) test, the timed “Up and Go” (TUG) test and the Activities-specific Balance Confidence (ABC) scale. [Results] The SST showed good to excellent intra-rater, inter-rater and test-retest reliability. The SST counts correlated with 5TSTS times, 10mW times, TUG times, and the FMA-LE and BBS scores. SST counts of 11 for the paretic leg and 14 for the non-paretic leg were found to distinguish the healthy adults from subjects with stroke. [Conclusion] The sideways step test is a reliable clinical test, which correlates with the functional strength, gait speed, and functional balance of people with chronic stroke.Key words: Balance, Stroke, Rehabilitation  相似文献   
87.
88.

Objective

This study aimed to evaluate stress patterns generated within implant-supported mandibular overdentures retained by two different attachment types: ball and socket and locator attachments.

Materials and methods

Commercial CAD/CAM and finite element analysis software packages were utilized to construct two 3D finite element models for the two attachment types. Unilateral masticatory compressive loads of 50, 100, and 150 N were applied vertically to the overdentures, parallel to the longitudinal axes of the implants. Loads were directed toward the central fossa in the molar region of each overdenture, that linear static analysis was carried out to find the generated stresses and deformation on each part of the studied model.

Results

According to FEA results the ball attachment neck is highly stressed in comparison to the locator one. On the other hand mucosa and cortical bone received less stresses under ball and socket attachment.

Conclusions

Locator and ball and socket attachments induce equivalent stresses on bone surrounding implants. Locator attachment performance was superior to that of the ball and socket attachment in the implants, nylon caps, and overdenture. Locator attachments are highly recommended and can increase the interval between successive maintenance sessions.  相似文献   
89.
90.
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