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991.
Kang H. Zheng Sotirios Tsimikas Tania Pawade Jeffrey Kroon William S.A. Jenkins Mhairi K. Doris Audrey C. White Nyanza K.L.M. Timmers Jesper Hjortnaes Maximillian A. Rogers Elena Aikawa Benoit J. Arsenault Joseph L. Witztum David E. Newby Marlys L. Koschinsky Zahi A. Fayad Erik S.G. Stroes S. Matthijs Boekholdt Marc R. Dweck 《Journal of the American College of Cardiology》2019,73(17):2150-2162
Background
Lipoprotein(a) [Lp(a)], a major carrier of oxidized phospholipids (OxPL), is associated with an increased incidence of aortic stenosis (AS). However, it remains unclear whether elevated Lp(a) and OxPL drive disease progression and are therefore targets for therapeutic intervention.Objectives
This study investigated whether Lp(a) and OxPL on apolipoprotein B-100 (OxPL-apoB) levels are associated with disease activity, disease progression, and clinical events in AS patients, along with the mechanisms underlying any associations.Methods
This study combined 2 prospective cohorts and measured Lp(a) and OxPL-apoB levels in patients with AS (Vmax >2.0 m/s), who underwent baseline 18F-sodium fluoride (18F-NaF) positron emission tomography (PET), repeat computed tomography calcium scoring, and repeat echocardiography. In vitro studies investigated the effects of Lp(a) and OxPL on valvular interstitial cells.Results
Overall, 145 patients were studied (68% men; age 70.3 ± 9.9 years). On baseline positron emission tomography, patients in the top Lp(a) tertile had increased valve calcification activity compared with those in lower tertiles (n = 79; 18F-NaF tissue-to-background ratio of the most diseased segment: 2.16 vs. 1.97; p = 0.043). During follow-up, patients in the top Lp(a) tertile had increased progression of valvular computed tomography calcium score (n = 51; 309 AU/year [interquartile range: 142 to 483 AU/year] vs. 93 AU/year [interquartile range: 56 to 296 AU/year; p = 0.015), faster hemodynamic progression on echocardiography (n = 129; 0.23 ± 0.20 m/s/year vs. 0.14 ± 0.20 m/s/year] p = 0.019), and increased risk for aortic valve replacement and death (n = 145; hazard ratio: 1.87; 95% CI: 1.13 to 3.08; p = 0.014), compared with lower tertiles. Similar results were noted with OxPL-apoB. In vitro, Lp(a) induced osteogenic differentiation of valvular interstitial cells, mediated by OxPL and inhibited with the E06 monoclonal antibody against OxPL.Conclusions
In patients with AS, Lp(a) and OxPL drive valve calcification and disease progression. These findings suggest lowering Lp(a) or inactivating OxPL may slow AS progression and provide a rationale for clinical trials to test this hypothesis. 相似文献992.
《JACC: Cardiovascular Interventions》2020,13(21):2528-2538
ObjectivesThe aim of this study was to assess coronary accessibility after transcatheter aortic valve replacement (TAVR)–in–TAVR using multidetector computed tomography.BackgroundExpanding TAVR to patients with longer life expectancy may involve more frequent bioprosthetic valve failure and need for redo TAVR. Coronary access after TAVR-in-TAVR may be challenging, particularly as the leaflets from the initial transcatheter heart valve (THV) will form a neo-skirt following TAVR-in-TAVR.MethodsIn 45 patients treated with different combinations of CoreValve and Evolut (CV/EV) THVs with supra-annular leaflet position and SAPIEN THVs with intra-annular leaflet position, post-TAVR-in-TAVR multidetector computed tomographic scans were analyzed to examine coronary accessibility.ResultsAfter TAVR-in-TAVR, the coronary arteries originated below the top of the neo-skirt in 90% of CV/EV-first cases compared with 67% of SAPIEN-first cases (p = 0.009). For these coronary arteries originating below the top of the neo-skirt, the distance between the THV and the aortic wall was <3 mm in 56% and 25% of CV/EV-first and SAPIEN-first cases, respectively (p = 0.035). Coronary access may be further complicated by THV-THV stent frame strut misalignment in 53% of CV/EV-in-CV/EV cases. The risk for technically impossible coronary access was 27% and 10% in CV/EV-first and SAPIEN-first cases, respectively (p = 0.121). Absence of THV interference with coronary accessibility can be expected in 8% and 33% of CV/EV-first and SAPIEN-first cases, respectively (p = 0.005).ConclusionsCoronary access after TAVR-in-TAVR may be challenging in a significant proportion of patients. THVs with intra-annular leaflet position or low commissural height and large open cells may be preferable in terms of coronary access after TAVR-in-TAVR. 相似文献
993.
Gulser Esen Besli Cigdem Ulukaya Durakbasa Sema Yildirim Murat Acar Busra Cakir 《Pediatrics international》2015,57(6):1169-1171
Aortic dissection is extremely rare in children. Although it usually presents with severe chest pain, atypical clinical presentations mimicking various illnesses may cause misdiagnosis. In this report, the case of a 14‐year‐old boy with symptoms suggestive of acute abdomen, which was finally diagnosed as aortic dissection, is discussed. 相似文献
994.
Sekijima Y Hashimoto T Koshihara H Kawachi Y Otsuka F Ikeda S 《Modern rheumatology / the Japan Rheumatism Association》2005,15(5):361-363
We report a patient with hereditary angioedema (HAE) presenting with skin edema and abdominal pain. Laboratory examination
showed reduced levels of CH50, C2, C4, and C1 inhibitor (C1-INH). Abdominal computed tomography (CT) showed marked mesenteric
edema and wall thickening of the duodenum and transverse colon. Acute abdominal pain is common in HAE and is difficult to
distinguish from surgical emergency. Massive mesenteric edema on CT is a rare, but specific, sign suggesting HAE. 相似文献
995.
Knuuti J Takala TO Någren K Sipilä H Turpeinen AK Uusitupa MI Nuutila P 《Diabetologia》2001,44(2):184-187
Abstract
Aims/hypothesis. Fatty acids are an important source of energy in the myocardium. Abnormal myocardial fatty acid metabolism could contribute
to the deterioration of cardiac function frequently observed in patients with Type II (non-insulin-dependent) diabetes mellitus.
In our previous study, myocardial total uptake of non-esterified fatty acid (NEFA) was measured in patients with impaired
glucose tolerance and found to be normal. This study aimed to investigate the subsequent metabolic steps and β-oxidation of NEFA. Methods. A total of 6 men with impaired fasting glucose (age 50 ± 2 years, BMI 29 ± 1 kg/m2, means ± SEM) and 6 healthy men (50 ± 1 years, 25 ± 1 kg/m2) were studied in the fasting state. Myocardial blood flow was measured with [15O]H2O and positron emission tomography and myocardial NEFA metabolism with [11C]palmitic acid. Results. Myocardial blood flow was normal and not different between the impaired glucose tolerance and the control group (78 ± 6 vs
73 ± 13 ml/100 g/min, NS). The [11C]palmitic acid uptake indices were similar between the groups (10.4 ± 0.5 vs 11.2 ± 0.8 ml/100 g/min, respectively, NS).
The clearance of [11C]-palmitate from the myocardium, an index of NEFA β-oxidation, was similar between the groups (half-times of activity 17.6 ± 1.6 vs 19.5 ± 2.3 min, respectively, NS) Conclusion/interpretation. The results indicate that myocardial NEFA uptake and β-oxidation are not altered in patients with IGT. Thus, it is not likely that altered NEFA metabolism contributes to the deterioration
of the cardiac function in patients with IGT or Type II diabetes. [Diabetologia (2001) 44: 184–187]
Received: 9 June 2000 and in revised form: 25 September 2000 相似文献
996.
Myocardial beta adrenoceptor density in primary and secondary left ventricular hypertrophy 总被引:3,自引:0,他引:3
Choudhury L.; Rosen S. D.; Lefroy D. C.; Nihoyannopoulos P.; Oakley C. M.; Camici P. G. 《European heart journal》1996,17(11):1703-1709
OBJECTIVES: Myocardial ß-adrenoceptor density has been found tobe reduced in hypertrophic cardiomyopathy, even when systolicfunction is preserved. Our purpose in the current study wasto investigate whether ß-adrenoceptor down-regulationwas unique to hypertrophic cardiomyopathy, or is also presentin secondary myocardial hypertrophy. METHODS: Myocardial ß-adrenoceptor density was measured in11 patients with hypertrophic cardiomyopathy, eight patientswith left ventricular hypertrophy secondary to arterial hypertensionor aortic valve disease and 18 normal control subjects, usingpositron emission tomography with 11C-CGP-12177 as the myocardialß-adrenoceptor ligand. RESULTS: Reflecting the natural incidence of the conditions, the ageof the hypertrophic cardiomyopathy patients was 37 (10) [mean(SD), range 2051] years and that of the secondary hypertrophypatients 64 (18), [range 2680] years; P<0.01. Thecontrols' ages were 50 (13), [range 2165] years; however,since ß-adrenoceptor density is known to be influencedby age, the controls' data was split into groups matched tothe hypertrophic cardiomyopathy and secondary hypertrophy patientsets. For the hypertrophic cardiomyopathy patients, mean leftventricular ß-adrenoceptor was 7.70 (186) pmol . g1compared to 10.17 (244) pmol . g1 for a matched set of15 controls; P<0.01. In secondary left ventricular hypertrophy,ß-adrenoceptor was 6.35 (1.70) pmol . g1 comparedto 9.16 (2.00)pmol . g1 for a matched set of 10 controls;P<0.01. Plasma noradrenaline was 5.5 (2.2)nmol . 11in hypertrophic cardiomyopathy and 2.5 (1.0)nmol. 11for the matched controls; P<0.01. The results for adrenalinewere 2.2 (1.1) vs 0.4 (0.3) nmol . 11 respectively; P<0.001.For the secondary hypertrophy patients, the corresponding figureswere 2.5 (1.2) vs 2.5 (1.0) nmol . 11 for noradrenalinefor patients and controls respectively (P=ns); and for adrenaline0.2 (0.1) and 0.3 (0.2) nmol . 11 respectively, P=ns.On multiple regression analysis, no relationships could be demonstratedamongst plasma catecholamines, ß-adrenoceptor, myocardialblood flow and echocardiographic E/A ratio and fractional shortening. CONCLUSION: Myocardial ß-adrenoceptor density appears to be comparablydecreased in both primary and secondary left ventricular hypertrophyin the presence of preserved left ventricular systolic function. 相似文献
997.
998.
《Journal of the American College of Cardiology》2020,75(15):1844-1856
Acute ischemic stroke is the leading cause of disability and among the leading causes of mortality worldwide. Intravenous tissue plasminogen activator has been a cornerstone for treatment of acute ischemic stroke for more than 20 years; however, its use is limited due to a narrow therapeutic window, several contraindications, and low efficacy to recanalize the artery in large vessel occlusion. Recently, the addition of endovascular mechanical thrombectomy of large artery occlusion has revolutionized the stroke treatment for most disabling strokes. The paper reviews updates to the thrombolytic treatment as well as catheter-based treatment, and results from recent trials in the selection of patients in an extended time window using perfusion imaging. 相似文献
999.
Evaluation of treatment response using integrated 18F‐labeled choline positron emission tomography/magnetic resonance imaging in adolescents with intracranial non‐germinomatous germ cell tumours 下载免费PDF全文
1000.
目的观察肺动脉栓塞(PAE)在多层螺旋CT(MSCT)强化下扫描及后处理图象中的特征,评价其对肺动脉栓塞的诊断价值。方法35例可疑PAE病人均行MSCT强化扫描,并进行多平面重建(MPR)、最大密度投影(MIP)、容积再现(VR)及仿真内窥镜(VE)后处理。结果35例受检者主干肺动脉至段肺动脉的显示率为100%;对亚段及5级肺动脉的显示率为80.23%。在35例中32例可见到不同部位、不同类型和形态的充盈缺损,并有不同种类的间接征象。3例未见肺动脉内充盈缺损,其中2例各有1种间接征象。结论多层螺旋CT扫描及重建后处理是肺动脉栓塞的快速、有效、安全、简便可行的诊断方法。 相似文献