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1.

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   
2.
Pulmonary thromboembolism (PTE) is an important cause of mortality/morbidity even today despite advancement in clinical understanding as well as diagnostic facilities. Clinical diagnosis of PTE is often challenging because of nonspecific sign/symptoms. Adherence to clinical decision-making protocols and appropriate use of diagnostic modalities like computed tomography pulmonary angiography can resolve the diagnostic dilemma in most cases and help in the overall management of PTE. This article deals with various concerns as well as controversies surrounding accurate diagnosis of PTE as on date.  相似文献   
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Early development of the fovea has been documented by histological studies over the past few decades. However, structural distortion due to sample processing and the paucity of high-quality post-mortem tissue has limited the effectiveness of this approach. With the continuous progress in high-resolution non-invasive imaging technology, most notably optical coherence tomography (OCT) and OCT angiography (OCT-A), in vivo visualization of the developing retina has become possible. Combining the information from histologic studies with this novel imaging information has provided a more complete and accurate picture of retinal development, and in particular the developing fovea.Advances in neonatal care have increased the survival rate of extremely premature infants. However, with enhanced survival there has been an attendant increase in retinal developmental complications. Several key abnormalities, including a thickening of the inner retina at the foveal center, a shallower foveal pit, a smaller foveal avascular zone, and delayed development of the photoreceptors have been described in preterm infants when compared to full-term infants. Notably these abnormalities, which are consistent with a partial arrest of foveal development, appear to persist into later childhood and adulthood in these eyes of individuals born prematurely. Understanding normal foveal development is vital to interpreting these pathologic findings associated with prematurity.In this review, we first discuss the various advanced imaging technologies that have been adapted for imaging the infant eye. We then review the key events and steps in the development of the normal structure of the fovea and contrast structural features in normal and preterm retina from infancy to childhood. Finally, we discuss the development of the perifoveal retinal microvasculature and highlight future opportunities to expand our understanding of the developing fovea.  相似文献   
5.
PurposeTo develop and evaluate an automated method to measure the foveal avascular zone (FAZ) area in healthy eyes on Heidelberg Spectralis Optical Coherence Tomography Angiography (HS-OCTA). This method is referred to as the modified Kanno-Saitama macro (mKSM) which is an evolution of the Kanno-Saitama macro (KSM) approach.MethodsThis cross-sectional study included 29 eyes of 25 healthy volunteers who underwent HS-OCTA at the macular area twice at the same time. Regardless of the quality of the images, all of them were included. Macular data on the superficial vascular plexus, intermediate capillary plexus (ICP) and deep capillary plexus were processed by mKSM. The FAZ area was measured twice automatically using the mKSM and KSM and twice manually by two independent examiners.ResultsFrom 174 images, KSM could not measure correctly 31% while mKSM could successfully measure all of them. Intrascan intraclass coefficient ranged from 0.948 to 0.993 for manual measurements and was 1 for mKSM method. Despite that the difference between human examiners is smaller than between human examiners and mKSM according to Bland-Altman plots, the scatterplots show a strong correlation between human and automatic measurements. The best results are obtained in ICP.ConclusionsWith mKSM, the automated determination of the FAZ area in HS-OCTA is feasible and less human-dependent. It solves the inability of KSM to measure the FAZ area in suboptimal quality images which are frequent in daily clinical practice. Therefore, the mKSM processing could contribute to our understanding of the three vascular plexuses.  相似文献   
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目的:分析视网膜大动脉瘤(RAM)的多模态眼底影像学特点及疾病特征。方法:回顾性研究。连续 纳入2003年5月至2020年1月在北京协和医院眼科确诊的RAM患者57例(58眼)。分析患者彩色眼底 照相、荧光素血管造影(FFA)、吲哚菁绿血管造影(ICGA)及光学相干断层扫描(OCT)的影像学特点, 并总结疾病特征。结果:纳入患者年龄为(69.0±9.3)岁,其中女性占75%,单眼发病患者占98%, 共发现瘤体65个。彩色眼底照示95%的瘤体位于颞侧动脉,32%位于动脉主干,29%位于视网膜动 脉分支处或动静脉交叉处。85%伴不同程度出血,86%伴硬性渗出。FFA的瘤体检出率为92%,动脉 期可呈圆点状或梭状强荧光,周围出血或硬性渗出遮蔽荧光,晚期荧光增强并出现渗漏。ICGA的瘤 体检出率为95%,可透过出血的遮蔽荧光见视网膜动脉壁上瘤体高荧光,造影晚期瘤体荧光仍较背 景荧光强。OCT的瘤体检出率为63%,可见RAM局部高隆起,病灶处可见圆形强反射瘤体腔壁。结论: RAM常见于老年女性。多模态影像学检查可从多角度显示RAM的瘤体形态、活动性以及伴随的出 血、渗出表现。其中,ICGA对于瘤体的检出率更高,显示RAM更为清晰。  相似文献   
9.
《Indian heart journal》2021,73(5):549-554
ObjectiveRobotically assisted PCI offers a great alternative to S–PCI. This has gained even more relevance during the COVID-19 pandemic era however safety of R–PCI compared to S–PCI has not been studied well. This study explores the safety and efficacy of robotically assisted PCI (R–PCI) compared to standard PCI (S–PCI) for the treatment of coronary artery disease (CAD).MethodsPubMed, Scopus, Ovid, and Google scholar databases were searched for studies comparing R–PCI to S–PCI. Outcomes included clinical success, procedure time, fluoroscopy time, contrast use and radiation exposure.ResultsTheauthors included 5 studies comprising 1555 patients in this meta-analysis. Clinical success was comparable in both arms (p = 0.91). Procedure time was significantly longer in R–PCI group (risk ratio: 5.52, 95% confidence interval: 1.85 to 9.91, p = 0.003). Compared to S–PCI, patients in R–PCI group had lower contrast use (meandifference: −19.88, 95% confidence interval: −21.43 to −18.33, p < 0.001), fluoroscopy time (mean difference:-1.82, 95% confidence interval: −3.64 to −0.00, p = 0.05) and radiation exposure (mean difference:-457.8, 95% confidence interval: −707.14 to −208.14, p < 0.001).ConclusionR–PCI can achieve similar success as S–PCI at the expense of longer procedural times. However, radiation exposure and contrast exposure were lower in the R–PCI arm.  相似文献   
10.
BackgroundCompared with invasive fractional flow reserve (FFR), coronary CT angiography (cCTA) is limited in detecting hemodynamically relevant lesions. cCTA-based FFR (CT-FFR) is an approach to overcome this insufficiency by use of computational fluid dynamics. Applying recent innovations in computer science, a machine learning (ML) method for CT-FFR derivation was introduced and showed improved diagnostic performance compared to cCTA alone. We sought to investigate the influence of stenosis location in the coronary artery system on the performance of ML-CT-FFR in a large, multicenter cohort.MethodsThree hundred and thirty patients (75.2% male, median age 63 years) with 502 coronary artery stenoses were included in this substudy of the MACHINE (Machine Learning Based CT Angiography Derived FFR: A Multi-Center Registry) registry. Correlation of ML-CT-FFR with the invasive reference standard FFR was assessed and pooled diagnostic performance of ML-CT-FFR and cCTA was determined separately for the following stenosis locations: RCA, LAD, LCX, proximal, middle, and distal vessel segments.ResultsML-CT-FFR correlated well with invasive FFR across the different stenosis locations. Per-lesion analysis revealed improved diagnostic accuracy of ML-CT-FFR compared with conventional cCTA for stenoses in the RCA (71.8% [95% confidence interval, 63.0%–79.5%] vs. 54.8% [45.7%–63.8%]), LAD (79.3 [73.9–84.0] vs. 59.6 [53.5–65.6]), LCX (84.1 [76.0–90.3] vs. 63.7 [54.1–72.6]), proximal (81.5 [74.6–87.1] vs. 63.8 [55.9–71.2]), middle (81.2 [75.7–85.9] vs. 59.4 [53.0–65.6]) and distal stenosis location (67.4 [57.0–76.6] vs. 51.6 [41.1–62.0]).ConclusionIn a multicenter cohort with high disease prevalence, ML-CT-FFR offered improved diagnostic performance over cCTA for detecting hemodynamically relevant stenoses regardless of their location.  相似文献   
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