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1.
JACC Cardiovasc Imaging ; 17(3): 235-245, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37943232

RESUMEN

BACKGROUND: Speckle tracking strain echocardiography allows one to visualize the timing of maximum regional strain and quantifies left ventricular-mechanical dispersion (LV-MD). Whether LV-MD and LV-global longitudinal strain (LV-GLS) provide similar or complementary information in mortality risk stratification in patients with severe aortic stenosis (SAS) remains unknown. OBJECTIVES: The authors hypothesized that LV mechanical dyssynchrony assessed by LV-MD is associated with an increased risk of mortality and provides additional prognostic information on top of LV-GLS in patients with SAS. METHODS: A total of 364 patients with SAS (aortic valve area indexed ≤0.6 cm2/m2 and/or aortic valve area ≤1 cm2), LV ejection fraction ≥50% and no or mild symptoms were enrolled. The endpoint was overall mortality. RESULTS: During a median follow-up period of 41 months, 149 patients died. After adjustment, LV-MD ≥68 ms was significantly associated with an increased risk of mortality (adjusted HR: 1.41; 95% CI: 1.01-1.96; P = 0.044). Adding LV-MD ≥68 ms to a multivariable Cox regression model including LV-GLS ≥-15% improved predictive performance in terms of overall mortality, with improved global model fit, reclassification, and better discrimination. Patients with both criteria had an important increase in mortality compared to patients with none or one criterion (adjusted HR: 2.02; 95% CI: 1.34-3.03; P = 0.001). Interobserver reproducibility of LV-MD was good with an intraclass correlation coefficient of 0.90 (95% CI: 0.72-0.97). CONCLUSIONS: LV-MD is a reproducible parameter independently associated with an increased risk of mortality in SAS. Increased LV-MD associated with depressed LV-GLS identifies a subgroup of patients with an increased mortality risk. Whether early aortic valve replacement improves the outcome of these patients deserves further studies.


Asunto(s)
Estenosis de la Válvula Aórtica , Disfunción Ventricular Izquierda , Humanos , Pronóstico , Función Ventricular Izquierda , Volumen Sistólico , Factores de Riesgo , Medición de Riesgo , Reproducibilidad de los Resultados , Estenosis de la Válvula Aórtica/complicaciones , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estudios Retrospectivos , Valor Predictivo de las Pruebas , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/etiología
3.
Heart Vessels ; 37(3): 426-433, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34402942

RESUMEN

PURPOSE: Because of its diagnostic and prognostic value, right ventricular strain assessed by speckle-tracking imaging (RVS) has been incorporated into echocardiographic guidelines. However, it suffers from limitations including the need of good image quality and of dedicated software with inter-vendor variability. We hypothesized that RV free wall longitudinal fractional shortening (LFS) could be used as a substitute to RVS, without suffering from the aforementioned limitations. METHODS: We aimed to establish in a series of non-selected consecutive patients in sinus rhythm the value of LFS, calculated as [-(TAPSE/RVdiastolic length)] and of several common echocardiographic and Doppler parameters to predict an abnormal RV function, defined as RVS > - 20.2%. RESULTS: Among 144 consecutive patients, poor image quality precluded the assessment of RVS and of LFS in 31 and 4 patients, respectively (P = 0.0018), resulting in a final study group of 113 patients. The intraclass correlation coefficients for inter- and intra-observer variability were 0.97 (95% CI 0.92; 0.98) and 0.93 (CI 0.92; 0.98) for LFS and RVS, respectively. Among all tested RV function indices, LFS best correlated with RVS (R 0.97, 95% CI 0.81; 0.91). Bland-Altman analysis for the comparison between LFS and RVS showed no systematic bias. The area under the ROC-curve of the various RV function indices to detect abnormal RVS was best for LFS (0.97, 95% CI 0.94-1), with sensitivity, specificity, negative and positive predictive value of 83%, 96%, 96%, and 83%, respectively. CONCLUSION: LFS performs reasonably well to predict abnormal RVS and is more often feasible than RVS.


Asunto(s)
Disfunción Ventricular Derecha , Ecocardiografía/métodos , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Curva ROC , Disfunción Ventricular Derecha/diagnóstico por imagen , Disfunción Ventricular Derecha/etiología , Función Ventricular Derecha
4.
J Econ Entomol ; 107(4): 1496-501, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25195441

RESUMEN

The emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a serious invasive pest of North American ash (Fraxinus spp.) that has caused devastating mortality since it was first identified in North America in 2002. In 2012, we conducted field trapping assays that tested the efficacy of purple prism and fluon-coated green multifunnel (Lindgren funnel) traps. Traps were baited with combinations of several lures that were previously shown to be attractive to A. planipennis: manuka oil--a sesquiterpene-rich oil, (3Z)-hexenol--a green leaf volatile, or (3Z)-dodecen-12-olide [= (3Z)-lactone], a sex pheromone. Eighty-nine blocks (trap lines) were tested throughout nine states along the outer edges of the currently known A. planipennis infestation in North America. Trap catch was highest on fluon-coated green multifunnel traps, and trap detections at sites with low A. planipennis population density ranged from 72 to 76% for all trap and lure types tested. (3Z)-hexenol and (3Z)-lactone baited traps functioned as well as (3Z)-hexenol and manuka oil-baited traps. Independent of the lure used, detection rates on green fluon-coated multifunnel traps were comparable with glued purple prism traps in areas with low A. planipennis population densities.


Asunto(s)
Escarabajos , Control de Insectos/instrumentación , Animales , Hexanoles , Aceites de Plantas , Politetrafluoroetileno , Densidad de Población
5.
J Econ Entomol ; 106(6): 2407-14, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24498741

RESUMEN

The current emerald ash borer survey trap used in the United States is a prism trap constructed from a stock purple corrugated plastic. In recent years, several colors (particularly shades of green and purple) have been shown to be more attractive to the emerald ash borer than this stock color. Our goal was to determine if plastics produced with these colors and incorporated into prism traps can improve and serve as a new alternative to plastics already in use for the emerald ash borer survey. The plastics were tested in moderate to heavily infested areas in Michigan in two initial studies to test their effectiveness at catching the emerald ash borer. Because results from studies performed in heavily infested sites may not always correspond with what is found along the edges of the infestation, we compared trap catch and detection rates (recording at least one catch on a trap over the course of the entire trapping season) of several trap types and colors at sites outside the core of the currently known emerald ash borer infestation in a nine-state detection tool comparison study. Two of the new plastics, a (Sabic) purple and a medium-dark (Sabic) green were incorporated into prism traps and tested alongside a standard purple prism trap and a green multifunnel trap. In areas with lower emerald ash borer density, the new purple (Sabic) corrugated plastic caught more beetles than the current purple prism trap, as well as more than the medium-dark green (Sabic) prism and green multifunnel traps. Sabic purple traps in the detection tools comparison study recorded a detection rate of 86% compared with 73, 66, and 58% for the standard purple, Sabic green, and green multifunnel traps, respectively. These detection rates were reduced to 80, 63, 55, and 46%, respectively, at low emerald ash borer density sites.


Asunto(s)
Escarabajos/fisiología , Fraxinus/crecimiento & desarrollo , Control de Insectos/métodos , Animales , Densidad de Población , Estados Unidos
6.
J Econ Entomol ; 106(6): 2415-23, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24498742

RESUMEN

Field assays were conducted in southeastern and south-central Michigan in 2011 and 2012 to optimize green and purple multifunnel (Lindgren funnel) traps for use as a survey tool for the emerald ash borer, Agrilus planipennis Fairmaire. Larger sized (12- and 16-unit) multifunnel traps caught more beetles than their smaller-sized (4- and 8-unit) counterparts. Green traps coated with untinted (white) fluon caught almost four times as many adult A. planipennis as Rain-X and tinted (green) fluon-coated traps and almost 33 times more beetles than untreated control traps. Purple multifunnel traps generally caught much lower numbers of A. planipennis adults than green traps, and trap catch on them was not affected by differences in the type of coating applied. However, trap coating was necessary as untreated control purple traps caught significantly less beetles than traps treated with Rain-X and untinted or tinted (purple) fluon. Proportions of male beetles captured were generally much higher on green traps than on purple traps, but sex ratios were not affected by trap coating. In 2012, a new shade of purple plastic, based on a better color match to an attractive purple paint than the previously used purple, was used for trapping assays. When multifunnel traps were treated with fluon, green traps caught more A. planipennis adults than both shades of purple and a prism trap that was manufactured based on the same color match. Trap catch was not affected by diluting the fluon concentration applied to traps to 50% (1:1 mixture in water). At 10%, trap catch was significantly lowered.


Asunto(s)
Escarabajos/fisiología , Fraxinus/crecimiento & desarrollo , Control de Insectos/métodos , Animales , Color , Michigan
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