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Background

Patients with atrial myocardial infarction (ATMI) have frequent cardiac and noncardiac complications. However, ATMI is uncommonly diagnosed because of its nonspecific ECG changes. Our objective was to analyze the ECG characteristics of ATMI in patients with inferior STEMI.

Hypothesis

Electrocardiographic P wave parameters can help in diagnosis of ATMI.

Methods

We evaluated 932 patients who underwent coronary angiography and recruited 39 patients with ATMI and 33 patients without ATMI with inferior STEMI for a retrospective study. Twelve‐lead ECGs were obtained to measure P‐wave parameters in diagnosis of ATMI. P‐wave parameters and PR‐segment displacement were compared in patients with and without ATMI.

Results

In inferior leads, PWD and PWDisp were significantly longer in the ATMI group than in the non‐ATMI group (limb lead II, 109.79 ±15.51 ms and 86.65 ±5.02 ms, respectively; P < 0.001; limb lead III, 108.31 ±12.51 ms and 85.27 ±7.47 ms, P < 0.001; aVF, 106.49 ±13.68 ms and 83.01 ±7.89 ms, P < 0.001; PWDisp, 41.67 ±10.72 ms and 25.18 ±5.17 ms, P < 0.001). By contrast, PWA was significantly lower in the ATMI group than in the non‐ATMI group (limb lead II, 0.96 ±0.18 mV and 1.39 ±0.22 mV, respectively; P < 0.001; limb lead III, 0.90 ±0.11 and 1.21 ±0.23, P < 0.001; aVF, 0.88 ±0.17 and 1.26 ±0.28, P < 0.001). PR‐segment displacement was found in 8 (20.5%) patients with ATMI. A PWD ≥95.5 ms in lead DII diagnosed ATMI with a higher sensitivity and specificity (90%, 94%) than did PWA or PWDisp.

Conclusions

This study suggests P‐wave parameters might be considered ECG findings in diagnosis of ATMI in patients with inferior STEMI.  相似文献   
904.
Ebstein's anomaly is often accompanied by either Wolff-Parkinson-White syndrome or atriofascicular Mahaim. These bypass tracts give rise to antidromic atrioventricular (AV) re-entrant tachycardias, in which the bypass tract serves as the anterograde limb of the circuit and the AV node as the retrograde limb of the reentrant circuit. Since the antidromic AV reentrant tachycardia over a Mahaim fibre has a typically left bundle braunch block (LBBB) morphology, it is easy to make a misdiagnosis of supraventricular tachycardia with functional LBBB or even of ventricular tachycardia particularly in the presence of negative concordance. Some electrocardiographic clues might prevent misdiagnosis of ventricular tachycardia and inadvertent ICD implantation.  相似文献   
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Although the thalamus is not considered primarily as a limbic structure, abundant evidence indicates the essential role of the thalamus as a modulator of limbic functions indirectly through the amygdala. The amygdala is a central component of the limbic system and serves an essential role in modulating the core processes including the memory, decision‐making, and emotional reactions. The amygdalothalamic pathway is the largest direct amygdalo‐diencephalic connection in the primates including the human brain. Given the crucial role of the amygdalothalamic tract (ATT) in memory function and diencephalic amnesia in stroke patients, diffusion tensor imaging may be helpful in better visualizing the surgical anatomy of this pathway noninvasively. To date, few diffusion‐weighted studies have focused on the amygdala, yet the fine neuronal connection of the amygdala and thalamus known as the ATT has yet to be elucidated. This study aimed to investigate the utility of high spatial resolution diffusion tensor tractography for mapping the trajectory of the ATT in the human brain. We studied 15 healthy right‐handed human subjects (12 men and 3 women with age range of 24–37 years old). Using a high‐resolution diffusion tensor tractography technique, for the first time, we were able to reconstruct and measure the trajectory of the ATT. We further revealed the close relationship of the ATT with the temporopontine tract and the fornix bilaterally in 15 healthy adult human brains.  相似文献   
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Background/aim The effects of systemic magnesium sulfate (MgSO4) on retina in preterm hypoxic-ischemic (HI) rat model are not known. Our aim was to investigate the effects of MgSO4 on retinal ganglion cell (RGC) count, retinal ganglion cell (RGC) apoptotic index, retinal vascular endothelial growth factor receptor-2 (VEGFR-2), and glial fibrillary acidic protein (GFAP) expressions in preterm HI rat model.Materials and methods Fifteen, postnatal day (PND) 7 rat pups were divided into 3 groups: 1. Sham-operated group, 2. HI group, and 3. MgSO4-treated HI group. The second and third groups underwent ischemia followed by exposure to hypoxia for 2 h (Vannucci model). The first and second groups received intraperitoneal saline and the third group received intraperitoneal MgSO4. On PND 10, eyes of the pups were evaluated for RGC count, apoptotic index, VEGFR-2, and GFAP expressions. Results In both HI and MgSO4-treated HI group, the mean total RGC counts were found to be significantly decreased. However, the mean total RGC count in the MgSO4-treated HI group was significantly higher than that of the HI group. The mean apoptotic index was found to be significantly increased in the HI group. Retinal VEGFR-2 and GFAP expressions were found to be significantly higher in the HI group.ConclusionsMagnesium sulfate preconditioning andtreatment in preterm HI rat model might diminish apoptosis, relatively preserve RGCs, and reduce retinal VEGFR-2 and GFAP expressions.  相似文献   
910.
Hydatid cyst is a zoonotic infestation caused by Echinococcus granulosus, and it is known that some parasites found in humans cause cancer in humans or some may have a protective effect against cancer. Cancer is one of the most serious health problems of today and it has been shown in some studies that parasites such as Echinococcus granulosus can have an inhibitory effect. The aim of this study was determined as whether Echinococcus granulosus has an inhibitory effect on exocrine pancreatic cancer with the help of the azaserine-rat model used in different cancer studies.  Material and Methods: During experimental process a total of 45 male Wistar rats used, 14-day-old male Wistar rats were divided into groups according to the experimental protocol, administered azaserine injection protocol or kept as a control group without azaserine injection. Animals are grouped as Group 1, Control Group (group not treated with Azaserine and not injected with protoscolex.) (E-A-) (n=7); Group 2, Group injected with (IP) Azaserine only (30mg/kg) (E-A+)  (n=8);Group 3, Group injected (IP) with protoscolex suspension of 1 cc only (E+A-) (n=15);Group 4, Group injected both Azaserine (IP) and protoscolex suspension (IP) (E+A+) (n=15). Atypical Acinar Cell Foci (AACF) load in the exocrine pancreas of each rat was measured quantitatively with the help of a video image analyzer and the AACF load was calculated with the help of a mathematical model. Results: Findings showed that the Atypical Acinar Cell Foci (AACF) burden was statistically significantly lower in the Azaserine+ protoscolex (Azaserine-injected-protoscolex-implanted) rat group compared to the other groups, suggesting that Echinococcosis in the azaserine-rat model could inhibit the development of precursor foci of neoplastic changes in the exocrine pancreas. Conclusion: The most significant aspect of our study is that it contributes new insights into the controversy that Echinococcosis suppresses pancreatic cancer.  相似文献   
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