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101.
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Siu CW Tse HF Lee K Chan HW Chen WH Yung C Lee S Lau CP 《Pacing and clinical electrophysiology : PACE》2007,30(1):50-55
OBJECTIVES: We investigated the accuracy and feasibility of a 2D echo-independent ultrasonic continuous wave Doppler cardiac output monitoring device (USCOM) operated by trained nurse for the atrio-ventricular interval (AVI) optimization in cardiac resynchronization therapy (CRT). BACKGROUND: CRT is of proven benefit in patients with advanced chronic heart failure and ventricular conduction delay. Appropriate AVI selection is critical to optimize hemodynamic in CRT. Currently, most non-invasive methods for AVI optimization are often complicated and labor-intensive. Methods: USCOM method, Ritter method, and aortic outflow cardiac output method were used to determine the optima AVI in 20 patients with CRT. The accuracy and time for measurement of each method were determined. RESULTS: The optimal AVI determined by USCOM method had good correlation with Ritter's method and aortic outflow estimated cardiac output method (r2= 0.78, P < 0.01 and r2= 0.73, P < 0.01, respectively). The optimal AVI determined USCOM method showed good agreement (within 10 msec range) with Ritter's method (85% patients) and aortic outflow estimated cardiac output method (80%). The mean time for determining AVI using USCOM method was shorter than that with aortic outflow method (7.1 +/- 0.7 min vs 12.7 +/- 1.1 min, P < 0.01), whereas the mean time was shortest for Ritter method (4.7 +/- 1.6 min vs 7.1 +/- 0.7 min, P < 0.01). CONCLUSION: USCOM device operated by trained nurse can provide a simple, accurate, and fast non-invasive method for the AVI optimization in CRT population. 相似文献
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Yun-Bi Ni MMSC Julia Y. S. Tsang PhD Siu Ki Chan FHKCPath Gary M. Tse FRCPC 《Annals of surgical oncology》2014,21(9):2928-2933
Background
Histologic grade, TNM stage, and Nottingham Prognostic Index are traditional prognostic tools for breast cancer. “IHC-molecular” classification of breast cancer can also identify patients at different recurrence risks and provides insight into cancer therapy. However, cancers in each group are heterogeneous. A model based on the comprehensive analysis of morphologic features and molecular subtype was constructed to predict recurrence and refine these traditional prognostic tools.Methods
Morphologic features including histologic grade, fibrotic focus, extensive intraductal component, lymphocytic infiltrate, lymphovascular invasion, tumor necrosis, tumor margin and TNM stage, and molecular subtypes approximated by immunohistochemistry were analyzed in 633 patients with invasive breast carcinoma (excluding those with HER2 targeted therapy). Significant independent predictors for recurrence included: high histologic grade (p = 0.004), presence of lymphovascular invasion (p = 0.004), fibrotic focus (p = 0.020), mild lymphocytic infiltrate (p = 0.013), high TNM stage (p < 0.001), and HER2-overexpressing (p = 0.004) and basal-like (p < 0.001) molecular subtypes. A morphologic-molecular recurrence predictive model based on these features was useful in recurrence prediction, independent of treatment modalities, and was able to refine the traditional prognostic tools of histologic grade, TNM stage, and Nottingham prognostic index, particularly for intermediate-risk groups, and to refine the luminal group molecular subtypes. Such findings were reproducible with a validation cohort.Conclusion
TNM stage, histologic grade, lymphovascular invasion, fibrotic focus, mild lymphocytic infiltrate, HER2-overexpressing and basal-like molecular subtypes were important independent recurrence risk factors for breast cancer. This morphologic-molecular model was robust in recurrence prediction and refined recurrence risk stratified by the traditional prognostic parameters, independent of treatment modalities. 相似文献105.
106.
Abby C. Lee Grant Castaneda Wei Tse Li Chengyu Chen Neil Shende Jaideep Chakladar Pam R. Taub Eric Y. Chang Weg M. Ongkeko 《Viruses》2021,13(6)
Patients with underlying cardiovascular conditions are particularly vulnerable to severe COVID-19. In this project, we aimed to characterize similarities in dysregulated immune pathways between COVID-19 patients and patients with cardiomyopathy, venous thromboembolism (VTE), or coronary artery disease (CAD). We hypothesized that these similarly dysregulated pathways may be critical to how cardiovascular diseases (CVDs) exacerbate COVID-19. To evaluate immune dysregulation in different diseases, we used four separate datasets, including RNA-sequencing data from human left ventricular cardiac muscle samples of patients with dilated or ischemic cardiomyopathy and healthy controls; RNA-sequencing data of whole blood samples from patients with single or recurrent event VTE and healthy controls; RNA-sequencing data of human peripheral blood mononuclear cells (PBMCs) from patients with and without obstructive CAD; and RNA-sequencing data of platelets from COVID-19 subjects and healthy controls. We found similar immune dysregulation profiles between patients with CVDs and COVID-19 patients. Interestingly, cardiomyopathy patients display the most similar immune landscape to COVID-19 patients. Additionally, COVID-19 patients experience greater upregulation of cytokine- and inflammasome-related genes than patients with CVDs. In all, patients with CVDs have a significant overlap of cytokine- and inflammasome-related gene expression profiles with that of COVID-19 patients, possibly explaining their greater vulnerability to severe COVID-19. 相似文献
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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
109.
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
110.
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