55 research outputs found
Assessment of severity in aortic stenosis â Incremental value of endocardial function parameters compared to standard indexes
Several studies have reported that patients (pts) with severe aortic stenosis and similar pressure gradients or even similar aortic valve areas may have quite different symptomatic status and clinical outcomes suggesting that other factors might have a significant impact on the pathophysiology of this disease. Our purpose was to assess the severity of subendocardial wall dysfunction in symptomatic and asymptomatic pts with aortic stenosis using tissue Doppler imaging (TDI), strain rate imaging (SRI) and cyclic variation of integrated backscatter (IB). We studied 68 pts with aortic valvar stenosis and 46 subjects with no signs of heart disease. SRI/IB indexes were calculated in the apical four chambers views at endocardial level. Early diastolic endocardial strain rate showed the best correlation with transvalvar pressure gradients and valve areas. Compared with controls, symptomatic pts showed a more marked decrease in endocardial strain, strain rate and cyclic variation of IB. Receiver operating characteristic (ROC) curves suggested that the thresholds offering an adequate compromise between sensitivity and specificity for the prediction of symptoms were >/=60 mm Hg for the pressure gradient, less than 0.60 cm(2)/m(2) for aortic valve area, less than 20% for strain, less than 2.0 s(-1) for strain rate and less than 3.0 dB for cyclic variation. The combination of pressure gradient, aortic valve area and SRI/IB parameters resulted in an improvement of the overall performance for predicting the symptomatic state. Thus, SRI/IB parameters have an incremental value in differentiating symptomatic and asymptomatic pts with aortic stenosis compared with conventional hemodynamic parameters
Assessment of ascending aorta distensibility after successful coarctation repair by strain Doppler echocardiography
BACKGROUND: Increased arterial stiffness may participate in the genesis of hypertension and increase of left ventricular (LV) mass after surgical correction of coarctation of the aorta. The purpose of the current study was to assess the aortic elastic properties using Doppler tissue imaging and strain rate imaging in patients after coarctoplasty. METHODS: Echocardiography with Doppler tissue/strain rate imaging capabilities was performed in 26 adult normotensive patients who had successful repair of coarctation of the aorta in infancy and in 24 control subjects. Transesophageal aortic transverse sections were imaged at the level of the proximal and distal segments to the repair site. Doppler tissue imaging wall velocities during systole (S(w)), early relaxation (E(w)), and atrial systole (A(w)) and peak systolic strain (ps epsilon) were measured in both groups. Transthoracic ascending aorta (AAo) measurements were also obtained. RESULTS: In the patients with coarctoplasty, S(w) velocities and ps epsilon were significantly decreased in the proximal segments compared with control subjects. Both peak systolic blood pressure after exercise (P < .001) and pulse pressure after exercise (P < .001) were directly related to AAo wall strain. LV annular early diastolic velocity was significantly reduced compared with control subjects in patients with decreased AAo wall strain and exercise-induced hypertension (P < .001) and related to AAo wall velocity (P < .005) and strain (P < .001). In multiple linear regression analysis, only weight, study group, and AAo wall strain were correlated to LV mass index. CONCLUSIONS: Patients with coarctation of the aorta have reduced proximal aortic wall velocities and strain and increased stiffness even after successful repair. This amplifies stress-induced hypertension and increases LV burden
Adiponectin gene polymorphisms and their effect on the risk of myocardial infarction and type 2 diabetes: an association study in an Italian population.
Objective: While many studies have shown an association between the gene coding for adiponectin (ADIPOQ) and adiponectin levels, much more controversy surrounds its association with metabolic traits such as insulin resistance, obesity and type 2 diabetes. Furthermore, very few studies have looked into the relations between ADIPOQ variants and risk of cardiovascular disease. The present study assessed the influence of four common ADIPOQ Single Nucleotide Polymorphisms (SNPs), rs17300539 (-11391GâA), rs266729 (-11377CâG), rs2241766 (+45TâG) and rs1501299 (+276GâT) on the risk of myocardial infarction and type 2 diabetes. Methods and Results: A large genetic association case-control study was conducted in 2008 Italians, including patients with myocardial infarction, type 2 diabetes, or both, and a reference group of healthy controls. Homozygotes TT for the rs1501299 (+276) had half the risk of either myocardial infarction alone or in association with type 2 diabetes when compared to the carriers of the G allele (OR = 0.58, p =0.01, and OR = 0.55, p =0.006 respectively). SNPs rs17300539 (-11391), rs266729 (-11377) and rs2241766 (+45) showed no significant association with any of the three case groups. Conclusions: These results suggest that homozygotes TT for the adiponectin polymorphism rs1501299 (+276) are protected from the risk of myocardial infarction
Per lumina, per limina: percorsi nelle varianti a stampa di Andrea Zanzotto
Nell'articolo si presentano e commentano alcune (fino alla raccolta "Pasque") delle varianti a stampa individuate nell'opera poetica di Andrea Zanzotto. Si considerano le diverse edizioni delle raccolte poetiche e alcune plaquettes
Experimental investigation on the durability of a novel lightweight prefabricated reinforced-EPS based construction system
This paper investigates the durability of a low-cost construction system named HOMEDONE developed to realize affordable and also temporary housing solutions. The system is based on the assembly of 3D-reinforced EPS panels externally topped off with a multi-layer rendering system. Similar technologies showed durability issues, especially in hot climates, due to the thermal and hygrometric stresses of the thin finishing layers when coupled to thick EPS panels and exposed to extreme events. For this reason, in this work freezeâthaw and wet/drying-UV aging tests on HOMEDONE panels with different finishing systems have been carried out, monitoring macroscopic, microscopic (ATR-FT-IR analysis) and bond strength variations due to aging. Results have pointed out good mechanical properties of the system and only small color variations of the finishing layer due to UV cycles. Then, HOMEDONE can be considered as a durable option for affordable and temporary housing solutions
Evaluation of aortic wall mechanics in Marfan syndrome by transesophageal tissue Doppler echocardiography
Background: It has been described that the presence of aortic dilation is associated with an increased risk of aortic dissection in patients with Marfan disease. The aim of our study was to investigate the value of combined thoracic aorta dilation and decreased aortic elastic properties in assessing the severity of aortic disease in patients with Marfan syndrome.
Methods: Sixteen patients (pts) with Marfan syndrome (Beighton criteria) aged 13 to 45 years were studied with multiplane transesophageal echocardiography (TEE). 6/16 pts had surgery for aortic dissection. Tissue Doppler imaging (TDI, Toshiba corp.) during TEE was used for the quantification of aortic elastic properties. Eleven age-matched healthy subjects who had normal findings at TEE served as controls. The descending aorta was visualized in a TEE short axis view at the level of the left atrium. TDI tracing displayed accelerated expansion of the aortic wall followed by a slow deceleration, a plateau and then a rapid deceleration into diastole. Acceleration time (AT, msec), maximum wall expansion velocity (Vmax, cm/sec), and wall contraction velocities (cm/sec) were determined.
Results: Descending thoracic aorta dilation (>30mm) was present in 12/16 pts. Vmax values were significantly decreased compared to controls (p 40 mm had a sensitivity of 92%, specificity of 80% and positive predictive value of 77% for predicting aortic dissection.
Conclusion: Our results show that this combined 2D/TDI method is highly predictive for the development of aortic dissection in Marfan syndrome and should suggest aggressive treatment
Assessment of aortic wall mechanics in Marfan syndrome by transesophageal echocardiography and tissue Doppler imaging
Background. It has been described that aortic elastic properties are abnormal in patients with Marfan syndrome irrespective of the aortic diameter. The aim of our study was to investigate the potential value of transesophageal echocardiography combined with tissue Doppler imaging for the assessment of elastic properties of the thoracic aorta in patients with Marfan disease. Methods. Twentyone patients (pts) with Marfan syndrome (Gent criteria) aged 13 to 52 years were studied with multiplane transesophageal echocardiography (TEE). 7/21 pts had surgery for aortic dissection. Sixteen age- and gender-matched healthy subjects who had normal findings at TEE served as controls. The ascending and descending aorta were visualized in a TEE short axis view. Standard formulas and tissue Doppler imaging (TDI, Toshiba corp.) during TEE were used for the quantification of aortic elastic properties. Distensibility, stiffness index, and pulse wave velocity were calculated using M-mode data. TDI tracing displayed accelerated expansion of the aortic wall followed by a slow deceleration, a plateau and then a rapid deceleration into diastole. Acceleration time (AT, msec), maximum wall expansion velocity (Vmax, cm/sec), wall contraction E and A velocities (cm/sec), and peak systolic wall strain (e, %) were determined. Results. Ascending and descending thoracic aorta dilation (>40mm and >30mm) was present in 11/21 and 12/21 pts, respectively. Marfan patients had a lower distensibility and a higher stiffness index both in patients with dilated (p<.001) and normal aortas (p<.05). Highly significant differences were obtained between both groups for Vmax (2.8±1.6 vs 6.7±1.8 cm/sec, p<.0001), AT (68±7 vs 89±5msec, p<.0001) and strain (7.6±1.3% vs 24±2.9%, p<.0001). The indices derived from TDI were significantly decreased compared to controls both in patients with dilated (p<.0001) and normal aortas (p<.001). Significant and independent predictors of aortic dilatation were systolic blood pressure (F=19.2, p<.005), aortic stiffness index (F=21.3, p<.005), Vmax (F=31.2, p<.005), and strain (F=33.6, p<.005). Decreased aortic strain, Vmax and stiffness index were predictive of aortic dissection (Odds ratio = 3.9, p <.0001, 3.5, p <.0001, and 1.5, p<.005, respectively). Conclusion. Our results show that in Marfan syndrome elastic properties of the thoracic aorta are significantly different from normal controls, even in the absence of vessel dilatation. TDI assessment of aortic wall mechanics in Marfan patients is more accurate than standard M-mode measurements and is predictive of aortic dilatation and dissectio
Transesophageal echocardiography with tissue Doppler imaging in the assessment of global and regional systolic and diastolic right ventricular function in atrial septal defects.
Background. Evaluation of global and regional right ventricular (RV) systolic and diastolic function in atrial septal defects (ASD) is still a challenging post-surgical clinical problem, especially in adult patients (pts) We investigated whether high frame rate tissue Doppler imaging (TDI, Toshiba corp.) may provide quantitative assessment of RV function in ASD pts.
Methods. Twenty-three pts with ostium secundum ASD, aged 25±9 years, were studied with transesophageal echocardiography. Twelve pts underwent corrective surgery. 11 subjects with no signs of heart disease were used as a control group. ASD pts were classified in 3 groups according to 2D/color Doppler defect and shunt size (group â1â large, group â2â medium, group â3â small). Peak mean systolic (Sw) and diastolic (Ew, Aw) wall velocities were acquired from the 4-chamber view in the myocardia [septum (IVS) and free wall (FW)]. TDI wall velocities during systole (Sa), early relaxation (Ea) and atrial systole (Aa) were also measured in the tricuspid annulus. Satisfactory TDI data could be obtained in all pts at end expiration, independent of quality of RV wall motion.
Results. Compared to controls, group â1â pts had lower mean FW velocities (Sw= 5.5±1.9 vs 8.3±2.1 cm/s â p<0.005 â; Ew=5.8±1.9 vs 9.4±2.2 cm/s â p< 0.001 â; Aw=3.5±1.4 vs 3.6±1.8 cm/s â p=NS â) and lower annulus velocities both in systole and diastole (Sa =5.3±1.3 vs 8.9±1.3 cm/s â p<0.001 â ; Ea = 6.2±2.4 vs 13.3±2.4 cm/s â p< 0.001 â ; Aa = 7.8±2.2 vs 7.1±2.3 cm/s â p=NS â ). Also, group â1â pts had lower mean FW Sw and Ew velocities compared to IVS wall velocities (p < 0.005). Group â2â pts had preserved systolic velocities but decreased regional and annular early diastolic velocities suggesting impaired relaxation (Ea/Aa 0.87±0.28 vs 1.64±0.31 â p<0.0001 â ). Group â3â pts had preserved systolic and diastolic velocities.
Conclusion. Thus, TDI is useful in evaluating systolic and diastolic RV abnormalities, could corroborate the need of surgery in pts with volume overload, and may aid in monitoring RV function during post-surgical followup
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