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Introduction

Left ventricular (LV) dysfunction is estimated to occur in 10%–25% of the general intensive care unit (ICU) population and is frequently seen as regional wall motion abnormalities (RWMAs). Although RWMA is mostly attributed to myocardial ischemia or infarction, some studies have suggested that nonischemic RWMA might also be prevalent. We sought to establish that RWMA can be seen in critically ill patients with normal coronary arteries and to explore reasons for RWMA in this population.

Methods

In this retrospective study, data from the hospital angiography register and the ICU register were collated between 2012 and 2019. Patients were identified who underwent angiography in conjunction with their ICU stay and had RWMA on echocardiography. Patients were divided into either those with non-obstructed or those with obstructed coronary arteries. Cardiac magnetic resonance imaging (cMRI) examinations were reviewed if they had been performed on patients with non-obstructed coronaries.

Results

We identified 53 patients with RWMA and non-obstructed coronary arteries and 204 patients with RWMA and obstructed coronary arteries. Patients with non-obstructed coronary arteries were more often female, younger, and had fewer cardiovascular risk factors. They less commonly had ST elevation, but more frequently had T-wave inversion or serious arrhythmias. Troponin levels were higher in patients with obstructed coronary arteries, but NT-proBNP was similar between the groups. There were no differences in risk-adjusted 90-day mortality between patients with non-obstructed versus obstructed coronary arteries (OR 1.21, [95% CI 0.56–2.64], p = .628). In those with non-obstructed coronary arteries, follow-up echocardiography was available for 38 patients, of whom 30 showed normalization of cardiac function. Of the 14 patients with non-obstructed coronary arteries on whom cMRI was performed, 7 had a tentative diagnosis of Takotsubo syndrome or myocardial stunning; 4 had a myocardial infarction (preexisting in 3 cases); 1 patient had acute myocarditis; 1 patient had post-myocarditis; and 1 patient was diagnosed with dilated cardiomyopathy.

Conclusion

RWMA can be seen to occur in critically ill patients in the absence of coronary artery obstruction. Several conditions can cause regional hypokinesia, and cMRI is useful to evaluate the underlying etiology.  相似文献   
3.
BackgroundFoot orthoses (FOs) are used to manage foot pathologies such as plantar fasciopathy. 3D printed custom-made FOs are increasingly being manufactured. Although these 3D-printed FOs look like traditionally heat-moulded FOs, there are few studies comparing FOs made using these two different manufacturing processes.Research questionHow effective are 3D-printed FOs (3D-Print) compared to traditionally-made (Traditional) or no FOs (Control), in changing biomechanical parameters of flat-footed individuals with unilateral plantar fasciopathy?MethodsThirteen participants with unilateral plantar fasciopathy walked with shoes under three conditions: Control, 3D-print, and Traditional. 2 × 3 repeated measures analysis of variance (ANOVAs) with Bonferroni post-hoc tests were used to compare discrete kinematic and kinetic variables between limbs and conditions. Waveform analyses were also conducted using statistical parametric mapping (SPM).ResultsThere was a significant condition main effect for arch height drop (p = 0.01; ηp2 =0.54). There was 0.87 mm (95% CI [−1.84, −0.20]) less arch height drop in 3D-print compared to Traditional. The SPM analyses revealed condition main effects on ankle moment (p < 0.001) and ankle power (p < 0.001). There were significant differences between control condition and both 3D-print and Traditional conditions. For ankle moment and power, there were no differences between 3D-print and Traditional conditions.Significance3D-printed FOs are more effective in reducing arch height drop, whist both FOs lowered ankle plantarflexion moment and power compared to no FOs. The results support the use of 3D-printed FOs as being equally effective as traditionally-made FOs in changing lower limb biomechanics for a population of flat-footed individuals with unilateral plantar fasciopathy.  相似文献   
4.
目的:通过活体大蒜(garlic)及离体蒜苗(garlic sprout)挥发物对当归(Angelica sinensis)的化感效应,探索大蒜挥发性物质对连作当归存在的化感效应,为当归大蒜间作模式缓解连作当归胁迫提供一定的理论依据。方法:试验通过对当归各生长指标及叶片保护酶系统的测定分析,讨论当归在活体大蒜及离体蒜苗挥发物的影响作用下对连作胁迫、无连作胁迫环境的适应性及抗性生长发育机制。结果:整体分析,连作胁迫条件下离体蒜苗对当归幼苗化感效应处理(DC2)下的当归生长指标、叶片保护酶活性较当归单作(CK1)整体提高17. 51%,48. 34%;连作茬口种植活体蒜苗与当归间作处理(LC2)下的当归生长指标、叶片保护酶活性较当归单作(CK2)整体提高16. 63%,36. 65%;即离体蒜苗挥发物较活体大蒜缓解当归连作胁迫作用更显著。结论:无论有无连作障碍胁迫,适当浓度的活体大蒜及离体蒜苗挥发物对当归生长指标及叶片保护酶活性均表现为明显的化感促进作用,其化感促进作用在有连作胁迫条件下表现更显著,因而间作大蒜对当归连作障碍胁迫有一定的缓解作用。  相似文献   
5.
目的探讨衰减伪影对冠心病患者门控心肌灌注显像(GMPI)图像质量及灌注结果的影响。资料与方法回顾性分析2020年3月—2021年3月在郑州大学第一附属医院核医学科经冠状动脉造影证实且于造影前后1周行GMPI的99例冠心病患者的图像,定性及半定量分析衰减校正前后GMPI图像结果,比较衰减校正前后左心室各壁段平均放射性计数及灌注结果的差异,进一步分析衰减校正前后灌注结果不一致部分的受检者的节段性室壁运动及增厚情况。结果与衰减校正前比较,衰减校正后左心室间隔、下后壁及侧壁的平均放射性计数较高(Z=-7.302、-8.014、-3.991,P均<0.001),心尖部较低(Z=-8.021,P<0.001)。其中女性衰减校正后前壁平均放射性计数减低(Z=-2.314,P=0.021)。男性衰减校正前后下后壁放射性计数差值明显高于女性(t=-8.408,P<0.05)。衰减校正后44%(44/99)的左前降支及37%(37/99)的右冠状动脉分支供血区域显像结果发生改变,结合超声心动图及GMPI结果显示其中85%(35/41)的左前降支及81%(29/36)的右冠状动脉分支供血区域室壁运动及室壁增厚率均正常。结论衰减伪影对GMPI的图像质量和灌注结果有较大影响,结合室壁运动和增厚情况等有助于鉴别衰减伪影,提高诊断准确度与特异度。  相似文献   
6.
Fluorine‐19 (19F) MRI of injected perfluorocarbon emulsions (PFCs) allows for the non‐invasive quantification of inflammation and cell tracking, but suffers from a low signal‐to‐noise ratio and extended scan time. To address this limitation, we tested the hypotheses that a 19F MRI pulse sequence that combines a specific undersampling regime with signal averaging has both increased sensitivity and robustness against motion artifacts compared with a non‐averaged fully sampled pulse sequence, when both datasets are reconstructed with compressed sensing. As a proof of principle, numerical simulations and phantom experiments were performed on selected variable ranges to characterize the point spread function of undersampling patterns, as well as the vulnerability to noise of undersampling and reconstruction parameters with paired numbers of x signal averages and acceleration factor x (NAx ‐AFx ). The numerical simulations demonstrated that a probability density function that uses 25% of the samples to fully sample the k‐space central area allowed for an optimal balance between limited blurring and artifact incoherence. At all investigated noise levels, the Dice similarity coefficient (DSC) strongly depended on the regularization parameters and acceleration factor. In phantoms, the motion robustness of an NA8‐AF8 undersampling pattern versus NA1‐AF1 was evaluated with simulated and real motion patterns. Differences were assessed with the DSC, which was consistently higher for the NA8‐AF8 compared with the NA1‐AF1 strategy, for both simulated and real cyclic motion patterns (P < 0.001). Both strategies were validated in vivo in mice (n = 2) injected with perfluoropolyether. Here, the images displayed a sharper delineation of the liver with the NA8‐AF8 strategy than with the NA1‐AF1 strategy. In conclusion, we validated the hypotheses that in 19F MRI the combination of undersampling and averaging improves both the sensitivity and the robustness against motion artifacts.  相似文献   
7.
BackgroundOur study purpose was to determine if primary osteochondral allograft (OCA) transplant surgeries for large (>4 cm2) single-surface, multisurface, or bipolar articular defects in the knee would be associated with significant gains in knee range of motion (ROM) at ≥1-year follow-up when compared to preoperative ROM.MethodsPatients were prospectively enrolled into a dedicated registry to follow outcomes after OCA with or without meniscal allograft transplantation using Missouri Osteochondral Preservation System (MOPS)-preserved allografts. Patients were included if they had surgery to repair at least one osteochondral defect, and when at least one year of ROM data and Visual Analog Scale pain scores were available. Data on complications and reoperations, patient-reported outcome measures, compliance with rehabilitation, revisions, or failures were recorded.ResultsFor patients who met inclusion criteria after OCA surgery (n = 75), overall ROM increased from 127.8 ± 17 degrees preoperatively, to 130.5 ± 14 post-operatively. Non-compliance was the largest factor contributing to postoperative ROM lag or loss. Knee manipulation/lysis of adhesion rates were comparable to rates in TKA and ACL procedures (2.96–4.54% for ACL/TKA, 4% for OCAs in the present study).ConclusionResults suggest that OCA with or without meniscal allograft transplantation in the knee using high-viability grafts, advanced graft cutting and implantation techniques, and procedure-specific rehabilitation protocols can result in consistently successful outcomes in a high percentage (92%) of selected patients. Most patients (95%) can expect to regain, or improve, to “full” functional range of motion (130°) at 1 year after surgery such that highly functional activities can be performed.Level of Evidence: Cohort study; Level III.  相似文献   
8.
PurposeTo investigate the safety and effectiveness of primary conservative therapy for patients with symptomatic isolated mesenteric artery dissection (IMAD) with a severely compressed true lumen and/or a large dissecting aneurysm.Materials and MethodsA total of 35 consecutive patients (all men; median age, 53 y) with symptomatic IMAD with a severely compressed true lumen and/or a large dissecting aneurysm but without intestinal necrosis or arterial rupture who were treated with primary conservative therapy between November 2018 and February 2020 were assessed. A severely compressed true lumen was defined as luminal stenosis > 70%. A large dissecting aneurysm was defined as dissecting aneurysm diameter ≥ 1.5 times larger than the normal mesenteric artery diameter.ResultsThere was a strong positive relationship among abdominal pain, degree of luminal stenosis, and length of dissection (R = 0.811; P < .001). Conservative treatment was successful in all patients. Abdominal pain was eliminated within 4.7 d ± 4.8 (range, 2–31 d) in all patients, within 3.6 d ± 1.2 (range, 2–6) in the 31 patients with minor or moderate abdominal pain, and within 13.3 d ± 11.9 (range, 6–31 d) in the 4 patients with severe abdominal pain. Complete or partial remodeling of the mesenteric artery was achieved in 6 (17.1%) and 29 (82.9%) patients, respectively, during 8.6 mo ± 4.3 of follow-up.ConclusionsPrimary conservative therapy can be used safely and effectively in patients with symptomatic IMAD with a severely compressed true lumen and/or a large dissecting aneurysm but without intestinal necrosis or arterial rupture.  相似文献   
9.
BackgroundSpine posture, range of motion (ROM) and movement asymmetry can contribute to low back pain (LBP). These variables may have greater impact in populations required to perform repetitive spine movements, such as dancers; however, there is limited evidence to support this.Research questionWhat is the influence of dance and LBP on spinal kinematics?MethodsIn this cross-sectional study, multi-segment spinal kinematics were examined in 60 female participants, including dancers (n = 21) and non-dancers (n = 39) with LBP (n = 33) and without LBP (n = 27). A nine-camera motion analysis system sampling at 100 Hz was used to assess standing posture, as well as ROM and movement asymmetry for side bend and trunk rotation tasks. A two-way ANOVA was performed for each of the outcome variables to detect any differences between dancers and non-dancers, or individuals with and without LBP.ResultsCompared to non-dancers, dancers displayed a flatter upper lumbar angle when standing (p < 0.01, ηp2 = 0.15), and achieved greater frontal plane ROM for the upper lumbar (p = 0.04, ηp2 = 0.08) and lower thoracic (p = 0.02, ηp2 = 0.09) segments. There were no differences between dancers and non-dancers for transverse plane ROM (p > 0.05) or movement asymmetry (p > 0.05). There was no main effect for LBP symptoms on any kinematic measures, and no interaction effect for dance group and LBP on spinal kinematics (p > 0.05).SignificanceFemale dancers displayed a flatter spine posture and increased spine ROM compared to non-dancers for a select number of spine segments and movement tasks. However, the overall number of differences was small, and no relationship was observed between LBP and spinal kinematics. This suggests that these simple, static posture, ROM, and asymmetry measures often used in clinical practice can provide only limited generalisable information about the impact of dance or LBP on spinal kinematics.  相似文献   
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