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1.
Heart Lung Circ ; 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37806911

RESUMO

AIMS: With improved diagnosis and treatments, a greater percentage of breast cancer patients are achieving long-term survival. Consequently, long-term cardiotoxicity secondary to chemotherapy has become more prevalent, warranting improved cardiac surveillance. We evaluated changes in left atrial (LA) strain in breast cancer patients immediately post anthracycline (AC) therapy to assess its utility as a marker of diastolic dysfunction. METHODS: This was a prospective cohort study of 128 consecutive human epidermal growth factor receptor 2 (HER2)-negative breast cancer patients who underwent transthoracic echocardiography prior to and immediately post AC treatment. Traditional left ventricular (LV) systolic and diastolic parameters and LA volumes were evaluated; additionally, LV global longitudinal strain (LV GLS) and LA phasic strain were measured. RESULTS: All patients had normal LV ejection fraction (>53%) post AC, though LV GLS was significantly reduced. Peak E and é velocities were reduced post AC, with no change in LA volumes. LA reservoir strain (LASRES 34.8% vs 31.5%, p<0.001) and conduit strain (LASCD 17.2% vs 14.4%, p<0.001) were significantly lower post AC and correlated modestly with LV diastolic parameters. Reduction in LA strain post AC was evident even in patients with preserved LV systolic and diastolic function. More patients demonstrated alteration in diastolic function (≥15% reduction in LASRES from baseline) (32%) compared to alteration in systolic function (≥15% reduction in LV GLS) (23%). CONCLUSIONS: LA strain is a promising marker of early diastolic dysfunction. We demonstrate its potential utility in surveillance of breast cancer patients treated with AC.

2.
Curr Opin Cardiol ; 29(5): 408-16, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24945489

RESUMO

PURPOSE OF REVIEW: Evaluation of left atrial volume is important, as it is a biomarker of cardiovascular disease and outcomes and correlates with diastolic dysfunction severity. Left atrial volume measurements by different imaging modalities, including 2D and 3D echocardiography (2DE and 3DE), cardiac magnetic resonance (CMR) and computed tomography (CT), are reviewed in regard to recent advances, methodology, prognostic value and limitations. RECENT FINDINGS: Left atrial volume assessments correlate well between the different imaging modalities; however, 2DE significantly underestimates left atrial measurements. Assessment of the left atrial minimum volume and left atrial phasic function derived volumetrically have reported superior predictive value for major adverse cardiovascular events and elevated left ventricular diastolic pressure compared with the left atrial maximum volume. SUMMARY: The different imaging modalities used to assess left atrial volumes are not interchangeable, particularly for serial measurements. Although 2DE underestimates left atrial volumes, most normative as well as predictive data have been obtained using this modality. Standardization, with established normative data and classification criteria, needs to be established for other imaging modalities, additionally incorporating assessment of left atrial minimum and phasic volumes. Despite the limitations of the more simplistic 2DE, its measurements are well defined with significant prognostic value. The incremental prognostic value of the more complex imaging techniques needs to be further validated.


Assuntos
Átrios do Coração/diagnóstico por imagem , Ecocardiografia , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Tamanho do Órgão , Tomografia Computadorizada por Raios X
3.
Echocardiography ; 31(8): 956-64, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24447093

RESUMO

BACKGROUND: Chronic kidney disease (CKD) is associated with increased cardiovascular morbidity and mortality; hence detection of early cardiovascular involvement in CKD is important to prevent future adverse cardiovascular events. Left atrial (LA) enlargement and dysfunction has been reported in end stage renal disease. However, there is a paucity of published data regarding the evaluation of LA function in CKD using noninvasive imaging parameters. In this study, we evaluated biplane LA volume as well as LA function (LA global systolic strain (GS) and strain rate [SR]) in stage 3 CKD patients (eGFR 30-59 mL/min per 1.73 m(2) ) to determine if LA function parameters are more significantly altered by the presence of CKD in addition to changes due to hypertension alone. METHODS: Thirty-three CKD patients (eGFR 30-59 mL/min per 1.73 m(2) ) with hypertension were compared to 33 normal controls and 34 hypertensive (HT) subjects with normal renal function; all participants underwent a detailed transthoracic echocardiogram. Indexed biplane LA volume (LAVI), LA segmental function, and GS and SR (systolic, early, and late diastole) derived from tissue Doppler imaging (TDI) were measured. Univariate predictors of LA strain were determined. Multiple logistic regression analysis was used to examine the effect of patient group (i.e. CKD) on GS and SR as well as LAVI. RESULTS: Left atrial volume indexed was significantly increased in both the HT and CKD with HT group compared to normal controls (28 ± 9 mL/m(2) vs. 28 ± 9 mL/m(2) vs. 23 ± 5 mL/m(2) , respectively, P = 0.02). However, LAVI was similar in the HT and CKD with HT group (28 ± 9 mL/m(2) vs. 28 ± 9 mL/m(2) ; P = NS). LA GS and SR were reduced in both the CKD with HT and HT group, compared to controls. However, a significantly lower LA GS was present in the CKD with HT group (Controls vs. HT vs. CKD with HT: 54.9 ± 14.5% vs. 34.5 ± 6.2% vs. 25.7 ± 9.3%, respectively; P = 0.001). To examine the effect of group, (i.e. presence of CKD) multiple logistic regression analysis was performed with univariate predictors including indexed left ventricular mass (LVMI), LV diastolic grade, LAVI, peak A-wave velocity, ß-blocker therapy, GS and SR; this demonstrated that CKD had an independent effect on LA GS and SR (systolic, early, and late diastole). GS demonstrated moderate correlation with systolic blood pressure (r = -0.5, P = 0.01), diastolic grade (r = -0.5, P = 0.01), E' velocity (r = 0.6, P = 0.0001), peak A velocity (r = -0.5, P = 0.004), and LAVI (r = -0.6, P = 0.002). CONCLUSIONS: Left atrial dysfunction is evident in stage 3 CKD with associated LA enlargement. This study demonstrates that LA GS and SR were reduced in the CKD group despite similar LAVI in the CKD with HT and HT group. Hence LA GS and SR may be a more sensitive noninvasive tool to detect cardiovascular involvement in CKD.


Assuntos
Ecocardiografia/métodos , Cardiopatias/complicações , Cardiopatias/diagnóstico por imagem , Cardiopatias/fisiopatologia , Insuficiência Renal Crônica/diagnóstico por imagem , Insuficiência Renal Crônica/fisiopatologia , Idoso , Função Atrial , Técnicas de Imagem por Elasticidade/métodos , Feminino , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Insuficiência Renal Crônica/complicações , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
4.
ESC Heart Fail ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38887181

RESUMO

AIMS: Anthracycline chemotherapy (AC) for breast cancer can cause cancer therapy-related cardiac dysfunction (CTRCD) with resultant heart failure, traditionally defined as a reduction in left ventricular (LV) ejection fraction on echocardiography. In recent years, global longitudinal systolic strain (GLS) has been used to identify subclinical cardiac dysfunction prior to development of overt CTRCD. Recent harmonized guidelines have incorporated GLS into definitions for CTRCD to identify cardiac dysfunction and inform decisions regarding cardioprotective strategies. METHODS AND RESULTS: We evaluated subclinical dysfunction in breast cancer patients treated with AC and determined the echocardiographic and patient factors associated with significant GLS changes. One hundred fourteen HER2 negative patients treated with AC were prospectively recruited and underwent serial echocardiograms (LVEF and LVGLS) at three time points (prior to AC, 3 months, and 1 year). CTRCD was defined as an asymptomatic reduction in LVEF of 10% or symptomatic drop of 5% to LVEF <53%. Subclinical LV dysfunction was defined as a reduction of ≥10% in GLS compared with baseline, recognizing that this cut off identified an 'at risk cohort' rather than patients with established CTRCD. No participant demonstrated CTRCD by reduction in LVEF. Forty-three patients (38%) demonstrated a ≥10% relative reduction in GLS at 12 months; 20/43 (47%) had a reduced absolute GLS to <16%, and were older, had hypertension, increased LV mass, lower baseline e' velocity and GLS. GLS ≥20.5% at baseline yielded a sensitivity of 79% and specificity of 87% for a normal GLS (i.e., ≥16%) at 1 year despite a ≥10% reduction from baseline. CONCLUSIONS: We present a stepwise evaluation for subclinical LV dysfunction using both a relative reduction in GLS combined with an absolute reduction in GLS. We believe our findings may re-stratify patients with a high baseline GLS into a lower risk group despite transient relative GLS decrements ≥10%.

5.
Nanomaterials (Basel) ; 14(11)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38869607

RESUMO

Perfluorododecyl iodide (I-PFC12) is of interest for area-selective deposition (ASD) applications as it exhibits intriguing properties such as ultralow surface energy, the ability to modify silicon's band gap, low surface friction, and suitability for micro-contact patterning. Traditional photolithography is struggling to reach the required critical dimensions. This study investigates the potential of using I-PFC12 as a way to produce contrast between the growth area and non-growth areas of a surface subsequent to extreme ultraviolet (EUV) exposure. Once exposed to EUV, the I-PFC12 molecule should degrade with the help of the photocatalytic substrate, allowing for the subsequent selective deposition of the hard mask. The stability of a vapor-deposited I-PFC12 self-assembled monolayer (SAM) was examined when exposed to ambient light for extended periods of time by using X-ray photoelectron spectroscopy (XPS). Two substrates, SiO2 and TiO2, are investigated to ascertain the suitability of using TiO2 as a photocatalytic active substrate. Following one month of exposure to light, the atomic concentrations showed a more substantial fluorine loss of 10.2% on the TiO2 in comparison to a 6.2% loss on the SiO2 substrate. This more pronounced defluorination seen on the TiO2 is attributed to its photocatalytic nature. Interestingly, different routes to degradation were observed for each substrate. Reference samples preserved in dark conditions with no light exposure for up to three months show little degradation on the SiO2 substrate, while no change is observed on the TiO2 substrate. The results reveal that the I-PFC12 SAM is an ideal candidate for resistless EUV lithography.

6.
ESC Heart Fail ; 2024 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-39129371

RESUMO

BACKGROUND: Cardiac amyloidosis (CA) is an under-recognized cause of heart failure. Left atrial (LA) myopathy contributes to a worse prognosis in heart failure and is a feature of transthyretin (ATTR) and light-chain (AL) CA. LA mechanical dispersion (LA-MD) is a novel marker of intra-atrial dyssynchrony implicated in LA myopathy and the future development of atrial fibrillation (AF). AIMS: This study aimed to determine the characteristics and prognostic value of LA myopathy in ATTR and AL cardiomyopathy through a comprehensive LA echocardiographic evaluation. METHODS: ATTR (n = 86) and AL (n = 86) CA patients were compared with hypertensive heart disease (HHT) patients (n = 58). Transthoracic echocardiographic measurements including LA strain and LA-MD were obtained with patient follow-up for mortality. RESULTS: ATTR and AL patients had a median follow-up of 66 months, with 26 mortality events. Left ventricular (LV) mass, diastolic function (average-e' and E/e'), LV global longitudinal strain, and LA volume and function (LA function index and strain) were more impaired in ATTR versus AL; these echocardiographic parameters were more impaired in both amyloid groups compared to HHT patients (P < 0.05). LA-MD was increased in ATTR versus AL [median 72.2 (inter-quartile range 55-88.9) vs. 54 (43.5-64.2), respectively, P < 0.001]. Multivariable logistic regression adjusted for age, presence of AF, LV mass, global and basal strain, and E/e' demonstrated that LA-MD was an independent determinant of ATTR CA (P = 0.014). On multivariable analysis, LA reservoir strain was independently associated with the presence of heart failure in the CA group (P < 0.001). LA minimum volume (cut-off ≥18 mL/m2) was a determinant of mortality in AL CA [Cox proportional hazard ratio (HR) 1.042 (1.003-1.082), P = 0.034 and Kaplan-Meier analysis, P = 0.016]. CONCLUSION: Characterizing LA myopathy has significant diagnostic and prognostic utility in CA. ATTR patients have increased atrial dyssynchrony, which may have implications for AF development. LA reservoir strain was associated with heart failure in CA, whilst LA minimum volume was a predictor of mortality in AL CA.

7.
Eur Heart J Open ; 3(3): oead040, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37143609

RESUMO

Aims: The prognosis of light-chain (AL) amyloidosis, a plasma cell dyscrasia, is largely determined by the presence of cardiac involvement. Conventional staging is achieved using cardiac biomarkers (high-sensitivity troponin, N-terminal pro-beta natriuretic peptide) and free light-chain difference (Mayo staging). We sought to evaluate the role of echocardiographic parameters as prognostic markers in AL amyloidosis and examine their utility compared with conventional staging. Methods and results: Seventy-five consecutive patients with AL amyloidosis reviewed at a referral amyloid clinic who underwent comprehensive echocardiographic assessment were retrospectively identified. The evaluated echocardiographic parameters included left ventricular (LV) ejection fraction, mass, diastolic function parameters, global longitudinal strain (GLS), and left atrial (LA) volume. Mortality was assessed through a review of clinical records. During a median follow-up of 51 months, 29/75 (39%) patients died. Patients who died had a larger LA volume (47 ± 12 vs. 35 ± 10 mL/m2, P < 0.001) and a higher E/e' (18 ± 10 vs. 14 ± 6, P = 0.026). Univariate clinical and echocardiographic predictors of survival included LA volume, E/e', e', LVGLS, and Mayo stage (at significance of P < 0.1). Left atrial volume and LVGLS were significant determinants of mortality when examined using clinical cut-offs, although E/e' was not. A composite echocardiographic risk score comprising LA volume and LVGLS provided similar prognostic performance to Mayo stage [area under the curve (AUC) 0.75, 95% confidence interval (CI) 0.64-0.85 vs. AUC 0.75, 95% CI 0.65-0.858, P = 0.91]. Conclusion: Left atrial volume and LVGLS were independent predictors of mortality in AL amyloidosis. A composite echocardiographic score combining LA volume and LVGLS has similar prognostic power to Mayo stage for all-cause mortality.

8.
Front Cardiovasc Med ; 10: 1183485, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37465456

RESUMO

Aims: Differentiating phenotypes of cardiac "hypertrophy" characterised by increased wall thickness on echocardiography is essential for management and prognostication. Transthoracic echocardiography is the most commonly used screening test for this purpose. We sought to identify echocardiographic markers that distinguish infiltrative and storage disorders that present with increased left ventricular (LV) wall thickness, namely, cardiac amyloidosis (CA) and Anderson-Fabry disease (AFD), from hypertensive heart disease (HHT). Methods: Patients were retrospectively recruited from Westmead Hospital, Sydney, and Princess Alexandra Hospital, Brisbane. LV structural, systolic, and diastolic function parameters, as well as global (LVGLS) and segmental longitudinal strains, were assessed. Previously reported echocardiographic parameters including relative apical sparing ratio (RAS), LV ejection fraction-to-strain ratio (EFSR), mass-to-strain ratio (MSR) and amyloidosis index (AMYLI) score (relative wall thickness × E/e') were evaluated. Results: A total of 209 patients {120 CA [58 transthyretin amyloidosis (ATTR) and 62 light-chain (AL) amyloidosis], 31 AFD and 58 HHT patients; mean age 64.1 ± 13.7 years, 75% male} comprised the study cohort. Echocardiographic measurements differed across the three groups, The LV mass index was higher in both CA {median 126.6 [interquartile range (IQR) 106.4-157.9 g/m2]} and AFD [median 134 (IQR 108.8-152.2 g/m2)] vs. HHT [median 92.7 (IQR 79.6-102.3 g/m2), p < 0.05]. LVGLS was lowest in CA [median 12.29 (IQR 10.33-15.56%)] followed by AFD [median 16.92 (IQR 14.14-18.78%)] then HHT [median 18.56 (IQR 17.51-19.97%), p < 0.05]. Diastolic function measurements including average e' and E/e' were most impaired in CA and least impaired in AFD. Indexed left atrial volume was highest in CA. EFSR and MSR differentiated secondary (CA + AFD) from HHT [receiver operating curve-area under the curve (ROC-AUC) of 0.80 and 0.91, respectively]. RAS and AMYLI score differentiated CA from AFD (ROC-AUC of 0.79 and 0.80, respectively). A linear discriminant analysis with stepwise variable selection using linear combinations of LV mass index, average e', LVGLS and basal strain correctly classified 79% of all cases. Conclusion: Simple echocardiographic parameters differentiate between different "hypertrophic" cardiac phenotypes. These have potential utility as a screening tool to guide further confirmatory testing.

9.
ACS Appl Mater Interfaces ; 15(4): 6079-6091, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36649199

RESUMO

The rush for better-performing electronics, and manufacturing processes that heavily rely on "top-down" patterning techniques, is making the integration of "self-aligned" fabrication methods, such as area-selective deposition (ASD), a critical objective for continued device scaling. The fully self-aligned via (FSAV) scheme is broadly proposed as a "killer application" to determine whether ASD can shift from an R&D process to high-volume manufacturing. Nevertheless, the lack of a suitable low-κ deposition process has prevented the realization of FSAV by dielectric-on-dielectric ASD. This is primarily due to the high temperature and/or strong oxidizers employed during low-κ dielectric deposition and their unsuitability in the presence of organic masks, such as self-assembled monolayers (SAMs), used to prevent material nucleation during ASD. In this work, AlOx and Al-silicate atomic layer deposition (ALD) processes are studied to provide suitable materials for ASD-enabled FSAV. Dimethylaluminum isopropoxide and H2O are utilized to deposit the metal oxide, whereas Al-silicate is grown by adding 2,2-dimethoxy-1,6-diaza-2-silacyclooctane (DMDAcO) pulses to the AlOx ALD cycle. The selectivity of such processes is demonstrated on 50 nm Cu/SiO2 structures, using octadecanethiol-derived SAMs to inhibit material nucleation on the metal lines. Scanning and transmission electron microscopies are employed to assess the quality of the ASD processes and investigate the mechanisms behind defect generation on a nongrowth surface. X-ray photoelectron spectroscopy measurements show the high purity of the AlOx film, whereas DMDAcO-ligand incorporation into the Al-silicate matrix is observed. Planar capacitor structures are used to assess the electrical properties of both ASD films, revealing that the silicate film exhibits a relatively low κ-value (5.3 ± 0.2), with a high acceleration field factor (32.4 ± 1.4) and a dielectric breakdown voltage of 6.0 ± 0.3 V at 100 °C.

10.
J Phys Chem Lett ; 13(34): 8130-8133, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36000826

RESUMO

HfO2 is investigated for its suitability to act as an oxygen and moisture barrier to prevent Cu oxidation in redistribution layers (RDLs) in 3D packaging technologies. HfO2 barriers of varying thicknesses were deposited via atomic layer deposition (ALD) on Cu surfaces and then stressed by (i) high temperature stress and (ii) humidity and thermal stress for 1000 h to ascertain the optimal thickness to prevent oxidation of the Cu. The thickness of the ALD HfO2 film was monitored by ellipsometry, while the extent of Cu oxidation was monitored by focus ion beam prepared SEM cross sections. It is found that ∼9 nm of HfO2 is sufficient to prevent Cu oxidation.

11.
Amyloid ; 29(2): 128-136, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35188014

RESUMO

BACKGROUND: Cardiac involvement in AL amyloidosis portends a poor prognosis. 2D-speckle tracking echocardiography (2D-STE) strain can identify subclinical cardiac involvement. This study performed multilayer and multiplanar 2D-STE myocardial strain analysis. METHODS: We compared 75 AL amyloidosis patients to 49 hypertensive patients and 49 healthy controls. Longitudinal strain was obtained from epicardial, mid-myocardial and endocardial layers; segmental strain was measured from mid-myocardial basal, mid and apical segments. RESULTS: Global longitudinal strain was reduced in epicardial (-14.3 ± -4.0% vs. -17.4 ± 2.2% vs. -17.5 ± -2.0%, p < .001), mid-myocardial (-16.3 ± -4.5% vs. -19.7 ± 2.5% vs. -19.7 ± -2.2%, p < .001) and endocardial layers (-18.7 ± -4.9% vs. -22.2 ± 3.0% vs. -22.3 ± -2.6%, p < .001) in amyloid patients compared to hypertensive and healthy controls. Segmental strain confirmed significant reduction in basal (-11.2 ± -3.9% vs. -17.6 ± 2.7% vs. -20.9 ± -3.4%, p < .001) and mid (-14.8 ± -4.3% vs. -19.2 ± 2.5% vs. -19.6 ± -2.2%, p < .001) LV segments in the AL amyloid group. Receiver operating curve analysis demonstrated that an optimal cut-off of -16% for basal segmental strain better differentiated AL amyloid from hypertensive group (sensitivity 96%, specificity 70%, AUC 0.93), compared to relative apical sparing (AUC of 0.85). CONCLUSION: Strain demonstrated myocardial involvement in all layers in AL amyloidosis, with reduced basal segmental longitudinal strain a likely marker of early disease.


Assuntos
Amiloidose , Amiloidose de Cadeia Leve de Imunoglobulina , Amiloidose/diagnóstico por imagem , Ecocardiografia , Humanos , Amiloidose de Cadeia Leve de Imunoglobulina/diagnóstico por imagem , Miocárdio , Função Ventricular Esquerda
12.
J Cardiovasc Dev Dis ; 9(1)2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-35050221

RESUMO

Fabry disease (FD) is an X-linked disorder with α-galactosidase A deficiency. Males (>30 years) and females (>40 years) often present with cardiac manifestations, predominantly left ventricular hypertrophy (LVH). The aim of this study was to evaluate electrocardiographic (ECG) characteristics within FD patients to identify gender related differences, and to additionally explore the association of ECG parameters with structural and functional alterations on transthoracic echocardiography (TTE). Retrospective cross-sectional analysis of 45 FD patients with contemporaneous ECG and TTE was performed and compared to age and gender matched healthy controls. FD patients demonstrated alterations in several ECG parameters particularly in males, including prolonged P-wave duration (91 vs. 81 ms, p = 0.022), prolonged QRS duration (96 vs. 84 ms, p < 0.001), increased R-wave amplitude in lead I (8.1 vs. 5.7 mV, p = 0.047), increased Sokolow-Lyon index (25 vs. 19 mV, p = 0.002) and were more likely to meet LVH criteria (31% vs. 7%, p = 0.006). FD patients with impaired basal longitudinal strain (LS) on TTE were more likely to meet LVH criteria (41% vs. 0%, p = 0.018). Those with more advanced FD (increased LV wall thickness on TTE) were more likely to meet LVH criteria but additionally demonstrated prolonged ventricular depolarization (QRS duration 101 vs. 88 ms, p = 0.044). Therefore, alterations on ECG demonstrating delayed atrial activation, delayed ventricular depolarization and evidence of LVH were more often seen in male FD patients. Impaired basal LS, a TTE marker of early cardiac involvement, correlated with ECG abnormalities. Increased LV wall thickness on TTE, a marker of more advanced FD, was associated with more severe ECG abnormalities.

13.
Eur J Echocardiogr ; 12(12): 945-52, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21965152

RESUMO

AIMS: The efficacy of anthracyclines is undermined by potential life-threatening cardiotoxicity. Cardiotoxicity is dependent upon several factors and the timing to its development is variable. Moreover, as adjuvant therapy with trastuzumab often follows, a close monitoring of cardiac function in those treated with anthracyclines is mandatory. Left ventricular ejection fraction (LVEF) by echocardiography is currently used for monitoring cardiotoxicity; however, LVEF has numerous limitations. Two-dimensional strain imaging may provide a more sensitive measure of altered LV systolic function, so the aim of the present study was to compare LVEF and LV systolic strain before and after anthracyclines. METHODS AND RESULTS: Fifty-two women with histologically confirmed breast cancer were prospectively studied. Echocardiographic LVEF (by Simpson's method), global and regional peak longitudinal, radial, and circumferential 2D systolic strain were measured 1 week before and 1 week after chemotherapy. Global and regional longitudinal LV systolic strain was significantly reduced after treatment; global longitudinal strain decreased from -17.7 to -16.3% (P < 0.01) with 48% of global measurements reduced by >10%. Global and regional radial LV systolic strain after treatment was also significantly reduced; global radial strain dropped from 40.5 to 34.5% (P < 0.01) with 59% of global measurements reduced by >10%. In contrast, no reduction in LVEF >10% after chemotherapy was observed. CONCLUSION: Reduced LV systolic strain immediately after anthracycline treatment may indicate early impairment of myocardial function before detectable change in LVEF.


Assuntos
Antraciclinas/efeitos adversos , Ventrículos do Coração/diagnóstico por imagem , Miocárdio , Disfunção Ventricular Esquerda/induzido quimicamente , Análise de Variância , Feminino , Ventrículos do Coração/efeitos dos fármacos , Humanos , Pessoa de Meia-Idade , Volume Sistólico/efeitos dos fármacos , Sístole , Ultrassonografia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular Esquerda/efeitos dos fármacos
14.
J Am Soc Echocardiogr ; 34(4): 405-413.e2, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33242609

RESUMO

BACKGROUND: Cardiac involvement in Anderson-Fabry disease (AFD) is associated with increased left ventricular (LV) wall thickness. The aim of this study was to evaluate if two-dimensional global and regional strain in patients with AFD can identify early myocardial involvement (when LV wall thickness and function are normal). Additionally, the association of altered strain with adverse cardiovascular events was evaluated. METHODS: In a retrospective cross-sectional study, 43 patients with AFD, before enzyme replacement therapy (mean age, 44 ± 12 years; 58.1% men), were compared with age- and gender-matched healthy control subjects. The mean follow-up duration among patients with AFD for major adverse cardiovascular events (MACE) was 82 months. RESULTS: LV ejection fraction was similar between groups (patients with AFD vs control subjects, 61 ± 8% vs 61 ± 6%; P = .89). However, global longitudinal strain (LS) was impaired in patients with AFD compared with control subjects (-16.5 ± 3.8% vs -20.2 ± 1.7%, P < .001), with greater impairment in patients with AFD with increased LV wall thickness (-15.4 ± 3.9% vs -18.7 ± 2.3%, P < .006). Additionally, LS was most impaired in the basal segments in patients with AFD (-14.8 ± 3.7% vs -20.3 ± 1.1%, P < .001). MACE occurred in 19 of 43 patients (four women, 15 men), and Kaplan-Meier analysis demonstrated that MACE were associated with impaired basal LS. CONCLUSIONS: In patients with AFD, altered basal LS is present even in those with normal LV wall thickness and is associated with MACE. Therefore, basal LS should be considered when screening for cardiac involvement in AFD, particularly in female patients with AFD with normal LV wall thickness.


Assuntos
Doença de Fabry , Disfunção Ventricular Esquerda , Adulto , Estudos Transversais , Doença de Fabry/complicações , Doença de Fabry/diagnóstico , Feminino , Humanos , Masculino , Miocárdio , Estudos Retrospectivos , Função Ventricular Esquerda
15.
Heart Lung Circ ; 19(7): 406-12, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20630352

RESUMO

AIMS: Even in 'healthy' individuals, ageing alters left ventricular diastolic function with a decrease in early diastolic filling. There is a paucity of data with regards to right ventricular (RV) parameters with normal ageing. We sought to determine the effect of ageing on RV size and function in a group of 'healthy' individuals. METHODS AND RESULTS: We retrospectively analysed echocardiograms from 60 healthy volunteers in three age groups (20-80 years) from a departmental database. RV area and volume were measured from the apical 4-chamber view and indexed to body surface area. Pulsed-wave tissue Doppler Imaging (TDI) was used to obtain right ventricular lateral annular systolic and diastolic velocities. Using Colour Doppler Tissue Imaging (CDTI), mean peak segmental velocities in systole (S') and in diastole (E', and A') were measured from the annular and mid-segments of the lateral RV. There was no change observed in RV area, volume or ejection fraction with increasing age. RV systolic function evaluated by RVEF and S' velocity were also unchanged with ageing. There was a significant decrease in CDTI and pulsed-wave TDI E' velocity with age (p<0.05) with a corresponding increase in A' velocity. CONCLUSION: Normal ageing leads to impaired RV relaxation with a reduction in E' velocity and amplification of the atrial component (A') without a change in overall RV volume or systolic function.


Assuntos
Envelhecimento/fisiologia , Ecocardiografia Doppler de Pulso , Ventrículos do Coração/diagnóstico por imagem , Função Ventricular Direita/fisiologia , Adulto , Idoso , Estudos Transversais , Feminino , Ventrículos do Coração/anatomia & histologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
Sci Total Environ ; 651(Pt 2): 2845-2856, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30463137

RESUMO

CuO nanostructured thin films supported on silicon with 6.5 cm2 area (geometric area greater than the studies reported in the literature) were synthesized by a chemical bath deposition technique. The electrodes were characterized by MEV, XRD, XPS, contact angle, cyclic voltammetry and electrochemical impedance spectroscopy analyses. To evaluate the photoelectrochemical properties of the CuO films, photocurrent-voltage measurements were performed using linear voltammetry. The catalytic activities of CuO nanostructures were evaluated by monitoring photodegradation of Mitoxantrone (MTX) under UV-A light irradiation. The method of photoelectrocatalysis (PEC), applying a voltage of 1.5 V and assisted by adding H2O2, was undertaken. To the best of our knowledge, no studies on the degradation of anticancer agents using PEC process have been found in the literature. For comparison purposes, experiments were performed under the same conditions by assisted photocatalysis (PC) with H2O2 and direct photolysis. CuO deposits consist of a needle-like morphology. The presence of CuO in the tenorite phase was evidenced by XRD and the XPS spectra showed the presence of copper(II) oxide. The increase in current under illumination shows that CuO exhibits photoactivity. The PEC system showed a 75% level of MTX degradation, while the level achieved using PC was 50%. Under UV-A light alone only 3% removal was obtained after 180 min. Up to 10 by-products were identified by chromatography-mass spectrometry (LC-MS) with m/z values ranging between 521 and 285 and a plausible degradation route has been proposed. It is worth mentioning that 9 by-products identified in this work, were not found in the literature in other studies of degradation or products generated as metabolites. The toxicity tests of MTX before and after PEC treatment with Artemia Salina and Allium cepa showed a decrease in the acute toxicity of the medium as the antineoplastic was degraded.


Assuntos
Antineoplásicos/química , Cobre/química , Mitoxantrona/química , Nanoestruturas/química , Processos Fotoquímicos , Antineoplásicos/análise , Antineoplásicos/toxicidade , Peróxido de Hidrogênio/química , Mitoxantrona/análise , Mitoxantrona/toxicidade , Modelos Químicos
17.
Am Heart J ; 156(6): 1056-64, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19032999

RESUMO

Left atrial (LA) volume has recently been identified as a potential biomarker for cardiac and cerebrovascular disease. However, evidence regarding the prognostic implications of LA volume still remains unclear. Evaluation of LA size and function using traditional and more recent echocardiographic parameters is potentially feasible in the routine clinical setting. This review article discusses the conventional and newer echocardiographic parameters used to evaluate LA size and function. Conventional parameters include the assessment of phasic atrial activity using atrial volume measurements, transmitral Doppler peak A velocity, atrial fraction, and the atrial ejection force. Newer parameters include Doppler tissue imaging (DTI) including segmental atrial function assessment using color DTI, strain, and strain rate. In addition, an overview of the implications and clinical relevance of the findings of an enlarged left atrium, from currently available literature, is presented.


Assuntos
Função do Átrio Esquerdo/fisiologia , Cardiomegalia/diagnóstico por imagem , Ecocardiografia , Átrios do Coração/diagnóstico por imagem , Fatores Etários , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/mortalidade , Fibrilação Atrial/fisiopatologia , Velocidade do Fluxo Sanguíneo/fisiologia , Volume Cardíaco/fisiologia , Cardiomegalia/mortalidade , Cardiomegalia/fisiopatologia , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/mortalidade , Doença das Coronárias/fisiopatologia , Ecocardiografia Doppler em Cores , Átrios do Coração/fisiopatologia , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Humanos , Contração Miocárdica , Prognóstico , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/fisiopatologia , Análise de Sobrevida
18.
Am J Cardiol ; 102(6): 784-9, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18774007

RESUMO

Myocardial velocities have prognostic implications, and transmitral E wave to mitral annular early diastolic tissue velocity ratio (E/Em) is utilized to estimate left ventricular (LV) end-diastolic pressure (EDP). There are no reference values for 2-dimensional (2D) speckle tracking myocardial velocities (S2D, E2D, A2D), and it is unknown if they are comparable with color tissue Doppler imaging (TDI). Predictors of E/E2D ratios are unknown and E/E2D has not been validated with LVEDP. The myocardial velocities of 142 subjects were measured by TDI and 2D speckle tracking. Mean E/Em and E/E2D were calculated as transmitral E wave to mean 6 basal early diastolic myocardial velocities using TDI and 2D speckle tracking respectively, and compared with LVEDP during catheterizations (n = 20). Mean E2D was lower but mean S2D and A2D were higher than TDI (all p <0.001). When TDI sample volume was tracked throughout the cardiac cycle, this directional difference was no longer apparent with S2D, E2D, and A2D higher than TDI (all p <0.05). Age, systolic blood pressure, LV ejection fraction, and mean S2D were independent correlates of E/E2D. Receiver-operator characteristic analysis showed E/E2D (p = 0.03), not E/Em, identified elevated LVEDP (> or =12 mm Hg). E/E2D of 11.6 had 83% sensitivity and 70% specificity to predict elevated LVEDP. In conclusion, TDI and 2D speckle tracking myocardial velocities are not comparable due to angle independency and ability for tissue tracking with the latter. LV systolic function, age, and afterload are independent correlates of E/E2D. Only E/E2D identifies elevated LVEDP, and an E/E2D of 11.6 has the optimal sensitivity and specificity.


Assuntos
Velocidade do Fluxo Sanguíneo , Circulação Coronária , Ecocardiografia/métodos , Fatores Etários , Idoso , Pressão Sanguínea , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Volume Sistólico , Sístole , Ultrassonografia Doppler em Cores , Ultrassonografia Doppler de Pulso
19.
Eur J Echocardiogr ; 9(1): 12-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17241819

RESUMO

AIMS: There is little known about segmental atrial function in patients with atrial arrhythmias. We evaluated segmental atrial contractility using colour Doppler tissue imaging (CDTI) in patients with chronic atrial fibrillation (CAF) who were successfully restored and maintained in sinus rhythm (SR). METHODS AND RESULTS: We compared the segmental atrial contractility in 39 CAF patients who were successfully cardioverted and maintained in SR for 6 months. Follow up echocardiograms were performed at baseline, 1 week, 1 month and 6 months and compared to a normal age matched cohort (n = 34). Using CDTI, mean peak velocities of atrial contraction were measured from annular, mid and superior segments of lateral and septal walls of the left atrium and right atrium in the apical four-chamber view. Segmental velocities from the posterior and anterior walls of the left atrium were measured from the apical two-chamber view. Segmental left atrial velocities improved over time in the CAF group, with the majority of the recovery occurring in the first month, but failed to normalise even at 6 months. In comparison, the right atrial velocities in the AF group had normalised at 1 month. CONCLUSION: Patients with CAF have persistent segmental left atrial dysfunction even 6 months after restoration and maintenance of SR, though right atrial velocities appear to normalise. This differential recovery indicates that left atrial function remains subnormal in patients with CAF despite maintenance of SR, suggesting underlying atrial myopathy or fibrosis as a consequence of CAF.


Assuntos
Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/terapia , Função do Átrio Esquerdo , Ecocardiografia Doppler em Cores , Cardioversão Elétrica , Idoso , Análise de Variância , Fibrilação Atrial/fisiopatologia , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Doença Crônica , Feminino , Humanos , Modelos Lineares , Masculino
20.
Cardiovasc Diagn Ther ; 8(1): 29-46, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29541609

RESUMO

The left atrium has an important role in modulating left ventricular filling and is an important biomarker of cardiovascular disease and adverse cardiovascular outcomes. While previously left atrial (LA) size was utilised, the role of LA function as a biomarker is increasingly being evaluated, both independently and also in combination with LA size. Strain analysis has been utilised for evaluation of LA function and can be measured throughout the cardiac cycle, thereby enabling the evaluation of LA reservoir, conduit and contractile function. Strain evaluates myocardial deformation while strain rate examines the rate of change in strain. This review will focus on the various types of strain analysis for evaluation of LA function, alterations in LA strain in physiological and pathologic states that alter LA function and finally evaluate its utility as a prognostic marker.

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