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991.
The relative concentration of autoradiographic grains was measured over the atrioventricular node of the adult rat heart 2 h after the intravenous injection of [3H]-leucine and 20 h after the induction of left ventricular cardiac hypertrophy by constriction of the abdominal aorta. In comparison with control tissues, the grain counts in equal area samples show a 32% greater concentration in the hypertrophying hearts. The results indicate a significantly increased rate of incorporation of amino acid into the proteins of nodal tissues accompanying early hypertrophic changes.  相似文献   
992.
We describe a 66-year-old female who presented with recurrent acute pulmonary edema and uncontrolled hypertension. She was diagnosed with left renal artery stenosis and treated with angioplasty and stent placement. Her clinical status improved initially but symptoms recurred within 4 months. Further evaluation documented renal artery in-stent restenosis, which was successfully treated with cutting balloon angioplasty followed by brachytherapy. The feasibility of renal artery brachytherapy and short-term follow-up is presented.  相似文献   
993.
OBJECTIVE—To determine the sensitivity and specificity of our transthoracic echocardiographic technique using high frequency (7.5 MHz) transducers for identification of the presence and type of coronary artery disease in patients with Kawasaki disease.
DESIGN—The results of the prospective echocardiographic study in each of seven segments of the four major coronary arteries were compared with the selective coronary angiograms.
SETTING—Kitasato University Hospital.
SUBJECTS—60 patients with Kawasaki disease, ranging in age from 8.0 months to 22 years (median, 6.0 years).
RESULTS—Adequate echocardiographic images were obtained in 397 (95%) of 420 coronary segments. Coronary angiography showed the presence of coronary aneurysms in 87 segments and stenosis or occlusion in 28. The overall sensitivity and specificity of cross sectional echocardiography for correctly identifying coronary aneurysms were 95% and 99%, respectively; for correctly identifying coronary stenosis or occlusion the values were 85% and 98% for the right coronary artery, and 80% and 97% for the left anterior descending coronary artery. Agreement on the presence or absence of coronary aneurysms and obstructive lesions on echocardiograms between the two observers was 1.0 and 0.98, respectively.
CONCLUSIONS—Echocardiography may provide a non-invasive means of identifying the presence and type of coronary artery disease in patients with Kawasaki disease.


Keywords: Kawasaki disease; coronary artery aneurysm; coronary artery stenosis; echocardiography  相似文献   
994.

Objectives

This study sought to describe the current practices and compare outcomes according to the use of balloon aortic valvuloplasty (BAV) or not during transcatheter aortic valve replacement (TAVR).

Background

Since its development, aortic valve pre-dilatation has been an essential step of TAVR procedures. However, the feasibility of TAVR without systematic BAV has been described.

Methods

TAVR performed in 48 centers across France between January 2013 and December 2015 were prospectively included in the FRANCE TAVI (Registry of Aortic Valve Bioprostheses Established by Catheter) registry. We compared outcomes according to BAV during the TAVR procedure.

Results

A total of 5,784 patients have been included in our analysis, corresponding to 2,579 (44.6%) with BAV avoidance and 3,205 (55.4%) patients with BAV performed. We observed a progressive decline in the use of BAV over time (78% of procedures in 2013 and 49% in the last trimester of 2015). Avoidance of BAV was associated with similar device implantation success (97.3% vs. 97.6%; p = 0.40). TAVR procedures without BAV were quicker (fluoroscopy 17.2 ± 9.1 vs. 18.5 ± 8.8 min; p < 0.01) and used lower amounts of contrast (131.5 ± 61.6 vs. 141.6 ± 61.5; p < 0.01) and radiation (608.9 ± 576.3 vs. 667.0 ± 631.3; p < 0.01). The rates of moderate to severe aortic regurgitation were lower with avoidance of BAV (8.3% vs. 12.2%; p < 0.01) and tamponade rates (1.5% vs. 2.3%; p = 0.04).

Conclusions

We confirmed that TAVR without BAV is frequently performed in France with good procedural results. This procedure is associated with procedural simplification and lower rates of residual aortic regurgitation.  相似文献   
995.

Introduction and objectives

Left atrial dysfunction in aortic stenosis may precede atrial enlargement and predict the occurrence of atrial fibrillation (AF). To test this hypothesis, we assessed left atrial function and determined its impact on the incidence of AF after aortic valve replacement.

Methods

A total of 149 severe aortic stenosis patients (74 ± 8.6 years, 51% men) with no prior AF were assessed using speckle-tracking echocardiography. Left atrial function was evaluated using peak atrial longitudinal strain (PALS), peak atrial contraction strain (PACS), and phasic left atrial volumes. The occurrence of AF was monitored in 114 patients from surgery until hospital discharge.

Results

In multiple linear regression, PALS and PACS were inversely correlated with left atrial dilation, left ventricular hypertrophy, and diastolic function. Atrial fibrillation occurred in 36 patients within a median time of 3 days [interquartile range, 1-4] after aortic valve replacement. In multiple Cox regression, PALS and PACS were independently associated with the incidence of AF (HR, 0.946; 95%CI, 0.910-0.983; P = .005 and HR, 0.932; 95%CI, 0.883-0.984; P = .011, respectively), even after further adjustment for left atrial dimensions. Both reduced PALS and PACS were associated with the incidence of AF in patients with nondilated left atria (P value for the interaction of PALS with left atrial dimensions = .013).

Conclusions

In severe aortic stenosis, left atrial dysfunction predicted the incidence of postoperative AF independently of left atrial dilation, suggesting that speckle-tracking echocardiography before surgery may help in risk stratification, particularly in patients with nondilated left atria.Full English text available from: www.revespcardiol.org/en  相似文献   
996.
Two cases of free-floating left atrial ball thrombi (FLABT) in association with mitral stenosis were observed by transesophageal echocardiography (TEE). Our report describes the relation between body position and thrombi kinetics. Both cases demonstrated similar kinetics. In the supine and right lateral decubitus positions, the thrombi recoiled from and sometimes became entrapped within the mitral valve. In the sitting and left lateral decubitus positions, the thrombi appeared to be nearly fixed and did not contact with the mitral valve. Our results indicate that the latter two positions prevent thrombi disintegration and incarceration into the mitral valve. Finally, TEE is an extremely useful tool for assessing the safest position for individuals with FLABT.  相似文献   
997.
Purpose  This prospective study was designed to find the incidence of symptomatic anastomotic stenosis after elective laparoscopic sigmoidectomy for diverticular disease. Methods  Sixty-eight patients who underwent elective laparoscopic sigmoidectomy with double-stapling colorectal anastomosis between November 1998 and June 2007 were included. Follow-up after hospitalization was performed by using sequential rectoscopy for all patients. Symptomatic patients with anastomotic stricture were treated. Results  No patient died postoperatively and no patient had anastomotic leak or abdominal septic complication. Twenty-two patients (32 percent) had postoperative symptoms that suggested anastomotic stenosis; 12 of them (17.6 percent) eventually needed dilatation of their anastomosis (median diameter of the stenosis: 7 mm) a mean time of 176 days postoperatively. Eight patients had only one session, three patients had two sessions, and one patient had three sessions. There were no complications and all patients were symptom-free after dilatation. Age, sex, obesity, hypertension, diabetes, and vascular preservation had no influence on the risk of anastomotic stenosis. Conclusions  Incidence of symptomatic anastomotic stenosis after elective laparoscopic sigmoidectomy is high (17.6 percent). No risk factor could be identified. Endoscopic dilatations were successful without complication in all cases. Regular rigid rectoscopy definitely should be part of the postoperative follow-up in symptomatic patients.  相似文献   
998.
AIMS: Left atrial appendage thrombi are believed to be the source of embolism in patients with rheumatic mitral stenosis in atrial fibrillation. There are a few studies which search the effects of left atrial appendage dysfunction in patients with mitral stenosis in sinus rhythm. METHODS AND RESULTS: Left atrial appendage function and flow patterns in 41 patients with rheumatic mitral stenosis in sinus rhythm and 11 healthy subjects were studied by transoesophageal echocardiography. Left atrial appendage flow profiles were recorded within the proximal third of the appendage. The left atrial appendage ejection fraction was expressed as (maximal area of appendage minimal area of appendage)/maximal area of appendage. In addition, two-dimensional imaging was used to determine the presence of spontaneous echocardiographic contrast and thrombus formation. Patients with mitral stenosis in sinus rhythm had significantly decreased left atrial appendage emptying and filling velocities compared to controls (0.40+/-0.15m/s vs 0.82+/-0.19 m/s and 0.42+/-0.21 m/s vs 0.68+/-0.28, respectively, P<0.001 and P<0.05). Compared with the control subjects, patients with mitral stenosis had significantly greater maximal area of the appendage and had reduced left atrial appendage ejection fraction (5.3+/-2.2 cm(2) vs 2.4+/-0.5 cm(2) and 50+/-16% vs 70+/-7%, respectively, P<0.001 and P<0.05). Of the patients with mitral stenosis in sinus rhythm, seven patients had spontaneous echocardiographic contrast and one of these had left atrial appendage thrombus. Compared with patients without spontaneous echocardiographic contrast, patients with spontaneous echocardiographic contrast had decreased left atrial appendage ejection fraction (33+/-21% vs 54+/-13%,P <0.01). One of the patients with mitral stenosis had central retinal artery occlusion, but thrombus was not observed in left atrial appendage. CONCLUSION: The study found that left atrial appendage dysfunction may occur in patients with mitral stenosis in sinus rhythm.  相似文献   
999.
OBJECTIVE—To assess the relation between coronary vasomotor effects of NG-monomethyl-L-arginine (LNMMA) administration and coronary stenosis morphology, length, and severity in patients with stable angina.DESIGN—In 28 patients (24 male, four female) with coronary artery disease and chronic stable angina, intracoronary normal saline and 4 µmol/min LNMMA were infused for four minutes each, followed by an intracoronary bolus of 250 µg glyceryl trinitrate. Coronary stenoses were classified as concentric (smooth), eccentric (smooth), or complicated (irregular). The diameters of these stenoses and their adjacent reference proximal segments were measured by quantitative angiography.RESULTS—During LNMMA infusion a significantly larger proportion of complicated stenoses than concentric and eccentric stenoses constricted by ? 5% (p < 0.01) and the magnitude of vasoconstriction was greater in complicated than in concentric and eccentric stenoses (p < 0.05). For complicated stenoses the magnitude of constriction (in mm) with reference to normal saline was greater than that of the concentric and eccentric stenoses (p < 0.05), whereas concentric and eccentric stenoses constricted similarly. Irrespective of the type of morphology, there was a correlation (p < 0.05) between both the severity and the length of stenoses and the magnitude of vasoconstriction to LNMMA. A similar proportion of concentric, eccentric, and complicated stenoses showed ? 5% increase in diameter with glyceryl trinitrate, and the magnitude of the response was similar in the three groups.CONCLUSIONS—In patients with coronary artery disease, the response to LNMMA is greater when stenosis morphology is complex, indicating greater nitric oxide activity. This provides further evidence that plaques with complex morphology are in an active state.  相似文献   
1000.

Introduction and objectives

Current therapeutic options for severe aortic stenosis (AS) include transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR). Our aim was to describe the prognosis of patients with severe AS after the decision to perform an intervention, to study the variables influencing their prognosis, and to describe the determinants of waiting time > 2 months.

Methods

Subanalysis of the IDEAS (Influence of the Severe Aortic Stenosis Diagnosis) registry in patients indicated for TAVI or SAVR.

Results

Of 726 patients with severe AS diagnosed in January 2014, the decision to perform an intervention was made in 300, who were included in the present study. The mean age was 74.0 ± 9.7 years. A total of 258 (86.0%) underwent an intervention: 59 TAVI and 199 SAVR. At the end of the year, 42 patients (14.0%) with an indication for an intervention did not receive it, either because they remained on the waiting list (34 patients) or died while waiting for the procedure (8 patients). Of the patients who died while on the waiting list, half did so in the first 100 days. The mean waiting time was 2.9 ± 1.6 for TAVI and 3.5 ± 0.2 months for SAVR (P = .03). The independent predictors of mortality were male sex (HR, 2.6; 95%CI, 1.1-6.0), moderate-severe mitral regurgitation (HR, 2.6; 95%CI, 1.5-4.5), reduced mobility (HR, 4.6; 95%CI, 1.7-12.6), and nonintervention (HR, 2.3; 95%CI, 1.02-5.03).

Conclusions

Patients with severe aortic stenosis awaiting therapeutic procedures have a high mortality risk. Some clinical indicators predict a worse prognosis and suggest the need for early intervention.  相似文献   
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