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排序方式: 共有1741条查询结果,搜索用时 218 毫秒
71.
Hideyuki Kawashima Patrick W. Serruys Rodrigo Modolo Michele Pighi Rutao Wang Masafumi Ono Jean-Paul Aben Chun Chin Chang Hadewych Van Hauwermeiren Bill Brunnett Martijn Cox Liesbeth Rosseel Darren Mylotte Philippe Pibarot Willem J. Flameng Yoshinobu Onuma Osama Soliman 《JACC: Cardiovascular Interventions》2021,14(14):1523-1534
ObjectivesThis study aimed to validate a dedicated software for quantitative videodensitometric angiographic assessment of mitral regurgitation (QMR).BackgroundQuantitative videodensitometric aortography of aortic regurgitation using the time-density principle is a well-documented technique, but the angiographic assessment of mitral regurgitation (MR) remains at best semi-quantitative and operator dependent.MethodsFourteen sheep underwent surgical mitral valve replacement using 2 different prostheses. Pre-sacrifice left ventriculograms were used to assess MR fraction (MRF) using QMR and MR volume (MRV). In an independent core lab, the CAAS QMR 0.1 was used for QMR analysis. In vitro MRF and MRV were assessed in a mock circulation at a comparable cardiac output to the in vivo one by thermodilution. The correlations and agreements of in vitro and in vivo MRF, MRV, and interobserver reproducibility for QMR analysis were assessed using the averaged cardiac cycles (CCs).ResultsIn vivo derived MRF by QMR strongly correlated with in vitro derived MRF, regardless of the number of the CCs analyzed (best correlation: 3 CCs y = 0.446 + 0.994x; R = 0.784; p =0.002). The mean absolute difference between in vitro derived MRF and in vivo derived MRF from 3 CCs was 0.01 ± 4.2% on Bland-Altman analysis. In vitro MRV and in vivo MRV from 3 CCs were very strongly correlated (y = 0.196 + 1.255x; R = 0.839; p < 0.001). The mean absolute difference between in vitro MRV and in vivo MRV from 3 CCs was –1.4 ± 1.9 ml. There were very strong correlations of in vivo MRF between 2 independent analysts, regardless of the number of the CCs.ConclusionsIn vivo MRF using the novel software is feasible, accurate, and highly reproducible. These promising results have led us to initiate the first human feasibility study comprising patients undergoing percutaneous mitral valve edge-to-edge repair. 相似文献
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INTRODUCTIONInfective haemodialysis catheter-related right atrial thrombus (CRAT) is a complication of tunnelled catheter use. Management recommendations are based mainly on published case series prior to 2011. We report our institution’s recent experience in managing infective haemodialysis CRAT and correlate treatment with outcomes.METHODSWe conducted a retrospective analysis of haemodialysis CRAT cases diagnosed on transthoracic echocardiography between 1 January 2011 and 31 December 2017. Clinical outcomes, including mortality at 180 days post diagnosis and thrombus resolution, were traced from electronic medical records.RESULTSThere were 14 cases identified. The median age was 59 (range 47–88) years and 11 (78.6%) were male. Sepsis was the most common reason for hospitalisation (71.4%). Blood cultures identified Staphylococcus aureus in seven cases, of which two were methicillin-resistant. Three had coagulase-negative Staphylococcus. All cases received antibiotics with infectious disease physician input. Seven were treated with catheter removal alone, of which three died within 180 days. Both cases treated with catheter removal plus anticoagulation survived at 180 days. Of the two cases who had anticoagulation without catheter removal, one died within 180 days and the other did not have thrombus resolution. Three underwent surgical thrombus removal, of which two died postoperatively and the last required repeated operations and prolonged hospitalisation. Mortality at 180 days post diagnosis was 42.9%.CONCLUSIONCatheter removal and anticoagulation are modestly effective. Surgery is associated with poor outcomes. Despite contemporary management, infective haemodialysis CRAT still results in high mortality. Prospective studies are needed to identify the optimal management. 相似文献
73.
James L. Cox Andrei Churyla Olga N. Kislitsina S. Chris Malaisrie Patrick M. McCarthy 《Journal of cardiovascular electrophysiology》2020,31(8):2118-2127
In the 1980s when surgery was first introduced for the treatment of atrial fibrillation (AF), one would often hear comments like “Every little old grandmother has AF. Why on earth would you operate on someone like that?”. 相似文献
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《JACC: Cardiovascular Imaging》2014,7(8):749-758
ObjectivesThis study sought to examine left atrial (LA) mechanics and the prognostic impact of patients with echocardiographic findings of E/A ratio ≤0.75, deceleration time (DcT) of mitral E-wave >140 ms, but E/ε′ ≥10.BackgroundTraditional diastolic dysfunction (DD) grading system could not classify every patient into a specific group. We considered the group of patients with E/A ≤0.75, DcT >140 ms, but E/ε′ ≥10 (proposed new DD grade) as a new group in the DD grading system.MethodsA total of 1,362 consecutive patients were stratified according to the new DD grading system, and the LA volumes, strain, and strain rates were measured by 2-dimensional speckle-tracking analysis. All patients were followed up to determine cardiac death and major adverse cardiac events.ResultsAn E/A ≤0.75, DcT >140 ms, but E/ε′ ≥10 was observed in 227 patients (17%). LA volumes in patients with the new DD grade were between those of the impaired relaxation group and the pseudonormal group. LA strain of the new DD grade was similar to that of the pseudonormal group, whereas LA booster function was preserved as in the impaired relaxation group. During a mean follow-up of 3.0 ± 1.1 years, 25 patients had cardiac death and 61 had major adverse cardiac events. Event-free survival for major adverse cardiac events of the new DD grade was worse than that of the impaired relaxation group but similar to that of the pseudonormal group.ConclusionsThe new DD grade is frequently observed and has a prognosis similar to that of the pseudonormal group but significantly worse than that of the impaired relaxation group. However, LA booster function was maintained at the expense of LA volume enlargement. Thus, the new grade should be a distinct entity for routine DD grading. 相似文献
78.
《JACC: Cardiovascular Interventions》2014,7(9):1036-1044
ObjectivesThis dual-center study sought to demonstrate the utility and safety of intracardiac echocardiography (ICE) in providing adequate imaging guidance as an alternative to transesophageal echocardiography (TEE) during Amplatzer Cardiac Plug device implantation.BackgroundOver 90% of intracardiac thrombi in atrial fibrillation originate from the left atrial appendage (LAA). Patients with contraindications to anticoagulation are potential candidates for LAA percutaneous occlusion. TEE is typically used to guide implantation.MethodsICE-guided percutaneous LAA closure was performed in 121 patients to evaluate the following tasks typically achieved by TEE: assessment of the LAA dimension for device sizing; guidance of transseptal puncture; verification of the delivery sheath position; confirmation of location and stability of the device before and after release and continuous monitoring to detect procedural complications. In 51 consecutive patients, we compared the measurements obtained by ICE and fluoroscopy to choose the size of the device.ResultsThe device was successfully implanted in 117 patients, yielding a technical success rate of 96.7%. Procedural success was achieved in 113 cases (93.4%). Four major adverse events (3 cardiac tamponades and 1 in-hospital transient ischemic attack) occurred. There was significant correlation in the measurements for device sizing assessed by angiography and ICE (r = 0.94, p < 0.0001).ConclusionsICE imaging was able to perform the tasks typically provided by TEE during implantation of the Amplatzer Cardiac Plug device for LAA occlusion. Therefore, we provide evidence that the use of ICE offered accurate measurements of LAA dimension in order to select the correct device sizes. 相似文献
79.
《Journal of the Saudi Heart Association》2014,26(2):73-79
BackgroundRight ventricular (RV) dysfunction is associated with poor prognosis in patients with heart failure (HF). Echocardiographic assessment of RV systolic function is challenging. The ability to visualize the right atrium (RA) allows a quantitative, highly reproducible assessment of RA volume.ObjectiveThe aim is to study the relationship between the right atrial volume index (RAVI) and prognosis in patients with chronic systolic HF.Methods120 patients with chronic systolic HF and left ventricular ejection fraction (LVEF) <40% were enrolled. The RA volume was calculated by Simpson’s method using single-plane RA area and indexed to body surface area (RAVI). RV systolic assessment was done using the RV fractional area change (RVFAC), and peak systolic velocity (Satri) using tissue Doppler imaging at the tricuspid annulus. The primary endpoint was death, urgent transplantation, or acute HF episode requiring hospital admission during a follow-up of 1 year.ResultsFollow up was complete for 117 of 120 patients. Fifty-two patients reached the primary endpoint. The mean RAVI was higher in patients with adverse events (45.5 ± 15 ml/m2 versus 25.2 ± 11 ml/m2, p < 0.001), and increased with worsening LVEF, RVFAC, Satri (Spearman’s r = −0.46, r = −0.45, r = −0.59, p < 0.001 for all). RAVI was not correlated with estimates of RV diastolic dysfunction. The cut-off threshold for RAVI to predict the primary endpoint using receiver-operating characteristic curve was 29 ml/m2 (area under the curve was 0.89%, 95% confidence interval: 0.82–0.95) with a sensitivity of 92%, and a specificity of 75%. NYHA > 2 (OR = 2.1, p < 0.01), and RAVI (OR = 1.6, p < 0.05) were found to be independent predictors of adverse outcome.ConclusionIn patients with chronic systolic HF, RAVI is an independent predictor of adverse outcome with a threshold value of 29 ml/m2. 相似文献