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101.
Bryce Alexander Gary Tse Manuel Martinez-Selles Adrian Baranchuk 《Current Cardiology Reviews》2021,17(1):68
Atrial conduction disorders result from impaired propagation of cardiac impulses from the sinoatrial node through the atrial conduction pathways. Disorders affecting interatrial conduction alter P-wave characteristics on the surface electrocardiogram. A variety of P-wave indices reflecting derangements in atrial conduction have been described and have been associated with an increased risk of atrial fibrillation (AF) and stroke. Interatrial block (IAB) is the most well-known of the different P-wave indices and is important clinically due to its ability to predict patients who are at risk of the development of AF and other supraventricular tachycardias. P-Wave Axis is a measure of the net direction of atrial depolarization and is determined by calculating the net vector of the P-wave electrical activation in the six limb-leads using the hexaxial reference system. It has been associated with stroke and it has been proposed that this variable be added to the existing CHA2DS2-VASc score to create a P2-CHA2DS2-VASc score to improve stroke prediction. P-Terminal Force in V1 is thought to be an epiphenomenon of advanced atrial fibrotic disease and has been shown to be associated with a higher risk of death, cardiac death, and congestive heart failure as well as an increased risk of AF. P-wave Dispersion is defined as the difference between the shortest and longest P-wave duration recorded on multiple concurrent surface ECG leads on a standard 12-lead ECG and has also been associated with the development of AF and AF recurrence. P-wave voltage in lead I (PVL1) is thought to be an electrocardiographic representation of cardiac conductive properties and, therefore, the extent of atrial fibrosis relative to myocardial mass. Reduced PVL1 has been demonstrated to be associated with new-onset AF in patients with coronary artery disease and may be useful for predicting AF. Recently a risk score (the MVP risk score) has been developed using IAB and PVL1 to predict atrial fibrillation and has shown a good predictive ability to determine patients at high risk of developing atrial fibrillation. The MVP risk score is currently undergoing validation in other populations. This section reviews the different P-wave indices in-depth, reflecting atrial conduction abnormalities. 相似文献
102.
Lee Kam-Ho Tse Man-Lap Donald Law Martin Cheng Andrew Kai-Chun Wong Ho-Yuen Frank Yu Man-Leung Li Yan-Lin Ho Yuen-Chi Chu Ferdinand Lam Wendy Wai-Man 《Abdominal imaging》2019,44(3):903-911
Abdominal Radiology - To develop and validate a scoring system using a combination of imaging and clinical parameters to predict 30-day mortality in ruptured HCC (rHCC) patients after transarterial... 相似文献
103.
Recent clinical and experimental studies have demonstrated that atrial fibrillation (AF) alters the electrical and mechanical remodeling of the atrium, which subsequently promote the maintenance and recurrence of AF. If atrial remodeling can be prevented with prompt and repeated cardioversion, the likelihood of AF recurrence may be reduced. Recent clinical studies have demonstrated that the strategies of transesophageal echocardiography facilitated early cardioversion and early repeated cardioversion may be clinically valuable in some patients who have persistent AF and recurrence of arrhythmia after the initial cardioversion. Furthermore, the use an implantable atrial defibrillator (IAD) for early repeated device-based cardioversion to maintain sinus rhythm appears to be safe and clinically feasible. Early cardioversion by IAD reduces AF burden, reverses atrial remodeling and prevents subsequent AF recurrence in selected patients without structural heart disease implanted with this device, indicating possible "sinus rhythm begets sinus rhythm". Despite encouraging initial observations, further long-term clinical studies in a larger patient population are needed to confirm this finding. Furthermore, whether the use of IAD in the fully automatic mode to provide immediate termination of AF episodes could intensify the potential beneficial effect and the clinical efficacy of this approach in patients with structural heart disease needs to be evaluated. 相似文献
104.
R S Chuck C R Cantor D B Tse 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(13):5021-5025
CD4 and T-cell antigen receptor (TCR) comodulate from the surface of human and murine T cells following exposure to monoclonal anti-CD4 or anti-TCR. This comodulation may occur because expression of CD4 and TCR is regulated by similar transmembrane signals or because CD4 and TCR are physically associated. To study multimolecular assemblies on the plasma membrane, we developed a flow cytometric method for detecting singlet-singlet energy transfer between fluorescein isothiocyanate (FITC)- and tetramethylrhodamine isothiocyanate (TRITC)-conjugated monoclonal antibodies as sensitized TRITC emission on intact, single cells. Using this procedure, we detected CD4-TCR complexes on the surface of the transformed human leukemia T cells, HPB-ALL, in the absence of stimulation. More than one CD4 were found in association with one TCR. CD4-TCR complexes were not in rapid equilibrium with free CD4 and free TCR, and they were not induced by the dye-labeled anti-CD4 or anti-TCR. 相似文献
105.
Purpose
Previous epidemiological studies on egg consumption and the risk of gastrointestinal (GI) neoplasms suggest a positive association; however, data are limited and the evidence remains controversial. This study aims to investigate and quantify the potential dose–response relationship with an evaluation of cancer site-specific differences.Methods
Relevant studies were identified after the literature search via electronic databases until January 2014. Subgroup analysis for serving portions was performed using two standardized classification methods: (1) less than 3, or 3 or more eggs per week; (2) less than 3, 3–5, or more than 5 eggs per week. Method two excludes studies that only reported consumption frequency. Pooled adjusted odds ratios (ORs) comparing highest and lowest categories of dietary pattern scores were calculated using a random-effects model.Results
Thirty-seven case–control and seven cohort studies were included for meta-analysis, which contained a total of 424,867 participants and 18,852 GI neoplasm cases. The combined odds ratio (OR) was calculated to 1.15 (95 % CI 1.09–1.22; p value heterogeneity <0.001), showing only a slight increase in risk. The correlation was stronger for colon cancers 1.29 (95 % CI 1.14–1.46; p value heterogeneity <0.22). Dose–response analysis revealed similar results with stratification methods, and the ORs for an intake of <3 and ≥3 eggs per week were 1.14 (95 % CI 1.07–1.22; p value heterogeneity = 0.38) and 1.25 (95 % CI 1.14–1.38; p value heterogeneity = 0.25), respectively. With method 2, the ORs for an intake of <3, 3–5, and >5 eggs per week were 1.13 (95 % CI 1.06–1.21; p value heterogeneity = 0.25), 1.14 (95 % CI 1.01–1.29; p value heterogeneity = 0.06), and 1.19 (95 % CI 1.01–1.39; p value heterogeneity <0.001), respectively.Conclusion
This study provides evidence that egg consumption is associated with a positive dose–response association with the development of GI neoplasms. 相似文献106.
107.
108.
Jehangir J. Appoo Leonard W. Tse Zlatko I. Pozeg Jason K. Wong Stuart J. Hutchison Alex J. Gregory Eric J. Herget 《The Canadian journal of cardiology》2014
Thoracic endovascular aortic repair, a minimally invasive technique is replacing the maximally invasive gold standard of thoracotomy and replacement of the descending thoracic aorta. With experience, indications have expanded to encroach on the arch and even ascending aorta. This review highlights the current state of technology, discusses controversies, and takes the perspective of a forward-thinking review to describe novel, innovative techniques that might make the entire thoracic aorta amenable to minimally invasive repair. 相似文献
109.
Kui Kai Lau Yuen Kwun Wong Yap Hang Chan Kay Cheong Teo Koon Ho Chan Leonard Sheung Wai Li Raymond Tak Fai Cheung Chung Wah Siu Shu Leong Ho Hung Fat Tse 《Atherosclerosis》2014
Background
Visit-to-visit blood pressure variability (BPV) is a simple surrogate marker for the development of atherosclerotic diseases, cardiovascular and all-cause mortality. Nevertheless, the relative prognostic value of BPV in comparison with other established vascular assessments remain uncertain.Methods
We prospectively followed-up 656 high-risk patients with diabetes or established cardiovascular or cerebrovascular diseases for the occurrence of major adverse cardiovascular events (MACEs). Baseline brachial endothelial function, carotid intima-media thickness (IMT) and plaque burden, ankle-brachial index and arterial stiffness were determined. Visit-to-visit BPV were recorded during a mean 18 ± 9 outpatient clinic visits.Results
After a mean 81 ± 12 month's follow-up, 123 patients (19%) developed MACEs. Patients who developed a MACE had significantly higher systolic BPV, more severe endothelial function, arterial stiffness and systemic atherosclerotic burden compared to patients who did not develop a MACE (all P < 0.01). BPV significantly correlated with all of the vascular assessments (P < 0.01). A high carotid IMT had the greatest prognostic value in predicting development of a MACE (area under receiver operating characteristic curve (AUC) 0.69 ± 0.03, P < 0.01). A high BPV also had moderate prognostic value in prediction of MACE (AUC 0.65 ± 0.03, P < 0.01). After adjustment of confounding factors, a high BPV remained a significant independent predictor of MACE (hazards ratio 1.67, 95% confidence interval 1.14-2.43, P < 0.01).Conclusions
Compared with established surrogate markers of atherosclerosis, visit-to-visit BPV provides similar prognostic information and may represent a new and simple marker for adverse outcomes in patients with vascular diseases. 相似文献110.
Yap-Hang Chan Kai-Hang Yiu Kui-Kai Lau Yuen-Fung Yiu Sheung-Wai Li Tai-Hing Lam Chu-Pak Lau Chung-Wah Siu Hung-Fat Tse 《Atherosclerosis》2014