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1.
J Med Entomol ; 50(1): 52-8, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23427652

RESUMEN

The Amazon rainforest and the Brazilian Cerrado both possess high phlebotomine diversity. The fragmentation of these habitats has resulted in the appearance of human cases of cutaneous leishmaniasis. In one altered area of mixed primary vegetation (forest and Cerrado) and its adjacent settlement in the northeast state of Maranhão, Brazil, evidence exists for the active transmission of cutaneous leishmaniasis. Accordingly, an entomological investigation was performed in both the forest and the settlement to compare the phlebotomine vector faunain each environment. The study was conducted from September 2009 to August 2010 in the municipality of Itapecuru Mirim in the state of Maranhão, Brazil. The phlebotomine species were captured using 24 light Center for Disease Control and Prevention traps that were placed in the forest and the settlement (peridomicile and intradomicile). The similarity between the phlebotomine compositions in the forest and those in the settlement was determined using a Principal Coordinate Analysis based on a dissimilarity matrix that was calculated using the Bray-Curtis index (relative abundance) and the Jaccard index (presence and absence of species). In total, 29 Lutzomyia species and one Brumptomyia species were collected. The phlebotomines were diverse and abundant in both the forest fragment (27 species, 4,606 specimens) and the settlement (22 species, 753 specimens). The most abundant species were L. infraspinosa (25%), L. davisi (21%), L. antunesi (21%), L. longipalpis (9%), L. saulensis (6%), L. flaviscutellata (5%), and L. wellcomei (4%). Some species were found strictly in the forest, other species were exclusive to the anthropic environment, and some species colonized both of the studied environments. The phlebotomines adaptation to these modified environments explains the autochthonous outbreak of cutaneous leishmaniasis.


Asunto(s)
Biodiversidad , Psychodidae , Animales , Brasil , Femenino , Vivienda , Humanos , Insectos Vectores , Leishmaniasis/transmisión , Masculino , Densidad de Población , Análisis de Componente Principal
2.
J Med Entomol ; 54(6): 1699-1703, 2017 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-28968803

RESUMEN

Numerous advantages over the standard incandescent lamp favor the use of light-emitting diodes (LEDs) as an alternative and inexpensive light source for sampling medically important insects in surveillance studies. Previously published studies examined the response of mosquitoes to different wavelengths, but data on anopheline mosquito LED attraction are limited. Center for Disease Control and Prevention-type light traps were modified by replacing the standard incandescent lamp with 5-mm LEDs, one emitting at 520 nm (green) and the other at 470 nm (blue). To test the influence of moon luminosity on LED catches, the experiments were conducted during the four lunar phases during each month of the study period. A total of 1,845 specimens representing eight anopheline species were collected. Anopheles (Nyssorhynchus) evansae (35.2%) was the most frequently collected, followed by An. (Nys.) triannulatus (21.9%), An. (Nys.) goeldii (12.9%), and An. (Nys.) argyritarsis (11.5%). The green LED was the most attractive light source, accounting for 43.3% of the individuals collected, followed by the blue (31.8%) and control (24.9%) lights. The LED traps were significantly more attractive than the control, independent of the lunar phase. Light trapping of anopheline mosquitoes was more efficient when the standard incandescent lamp was replaced with LEDs, regardless of the moon phase. The efficiency of LEDs improves light trapping results, and it is suggested that the use of LEDs as an attractant for anopheline mosquitoes should be taken into consideration when sampling anopheline mosquitoes.


Asunto(s)
Anopheles , Control de Mosquitos/instrumentación , Animales
3.
J Med Entomol ; 53(3): 634-638, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27026156

RESUMEN

A study to evaluate the use of light-emitting diodes (LEDs) as an attractant for phlebotomine sand flies at two animal pens in a livestock area in Brazil was performed. Light-suction traps were operated overnight with the following light sources: green, blue, and incandescent (control) lights. In total, 22 individual collections were made at each site and 44 with each trap type. In total, 2,542 specimens belonging to 14 phlebotomine species were collected. The most abundant species in the light traps were Nyssomyia whitmani, Evandromyia evandroi, Micropygomyia goiana, Lutzomyia longipalpis, and Bichromomyia flaviscutellata Taking the two sites together, the green-LED light was the most attractive, followed by the blue and incandescent lights, and the difference between the green-LED and the control was statistically significant. Most species were green-biased at both sites, but some species-specific differences were observed. However, even with these differences, the standard incandescent light was outcompeted by LEDs. The green-LED-biased response observed in the present study, together with numerous advantages in favor of LEDs, suggests that the green-LED light source can be used as an effective substitute for the currently used incandescent bulb in monitoring traps for phlebotomine sand flies in Brazil.


Asunto(s)
Control de Insectos/métodos , Psychodidae/fisiología , Animales , Brasil , Control de Insectos/instrumentación , Luz , Ganado/crecimiento & desarrollo , Ganado/parasitología , Psychodidae/efectos de la radiación
4.
J Med Entomol ; 53(5): 1163-1168, 2016 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-27343177

RESUMEN

This study investigates Culicoides infestation in peridomestic environments in two villages in Maranhão, one with hot and humid climate and the other with semihumid climate. We evaluated the composition, richness, abundance, and seasonality of species. We captured insects using CDC light traps installed in animal shelters once a month, from 6 pm to 6 am, for 24 mo (May 2012 to April 2014). In this study, 17 species were found. Of these, 10 occurred simultaneously in two areas; six were found only in hot and humid area, while one occurred only in the semihumid area. Species richness was higher in the hot and humid climate (16 species) than in the semihumid (11 species). The rank of abundance was uneven across areas: C. foxi, C. insignis, C. filariferus, C. ignacioi, and C. flavivenula were dominant in the hot and humid area, and C. ignacioi, C. foxi, C. filariferus, C. insignis, and C. boliviensis in the semihumid. Midges were more abundant in the rainy season in both areas. This result reveals a diversified fauna of midges, with variable abundance of rank according to the area, prevailing in the rainy season and in the Amazon area. It also highlights the need for health monitoring in order to contain the infestation by these insects in peridomestic environments, taking into account that some species can be effective vectors of arboviruses in the Amazon and northeastern Maranhão.

5.
J Mol Biol ; 297(1): 135-46, 2000 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-10704312

RESUMEN

The aldehyde oxidoreductase (MOD) isolated from the sulfate reducer Desulfovibrio desulfuricans (ATCC 27774) is a member of the xanthine oxidase family of molybdenum-containing enzymes. It has substrate specificity similar to that of the homologous enzyme from Desulfovibrio gigas (MOP) and the primary sequences from both enzymes show 68 % identity. The enzyme was crystallized in space group P6(1)22, with unit cell dimensions of a=b=156.4 A and c=177.1 A, and diffraction data were obtained to beyond 2.8 A. The crystal structure was solved by Patterson search techniques using the coordinates of the D. gigas enzyme. The overall fold of the D. desulfuricans enzyme is very similar to MOP and the few differences are mapped to exposed regions of the molecule. This is reflected in the electrostatic potential surfaces of both homologous enzymes, one exception being the surface potential in a region identifiable as the putative docking site of the physiological electron acceptor. Other essential features of the MOP structure, such as residues of the active-site cavity, are basically conserved in MOD. Two mutations are located in the pocket bearing a chain of catalytically relevant water molecules. As deduced from this work, both these enzymes are very closely related in terms of their sequences as well as 3D structures. The comparison allowed confirmation and establishment of features that are essential for their function; namely, conserved residues in the active-site, catalytically relevant water molecules and recognition of the physiological electron acceptor docking site.


Asunto(s)
Aldehído Oxidorreductasas/química , Aldehído Oxidorreductasas/genética , Desulfovibrio/enzimología , Aldehído Oxidorreductasas/metabolismo , Secuencia de Aminoácidos , Sitios de Unión , Secuencia Conservada , Cristalización , Cristalografía por Rayos X , Nucleótidos de Citosina/metabolismo , Desulfovibrio/genética , Dimerización , Enlace de Hidrógeno , Proteínas Hierro-Azufre/química , Proteínas Hierro-Azufre/genética , Proteínas Hierro-Azufre/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Mutación/genética , Oxidación-Reducción , Estructura Secundaria de Proteína , Pterinas/metabolismo , Alineación de Secuencia , Electricidad Estática , Relación Estructura-Actividad , Agua/metabolismo
6.
Rev Soc Bras Med Trop ; 33(5): 443-50, 2000.
Artículo en Portugués | MEDLINE | ID: mdl-11064581

RESUMEN

The Anophelae species of the municipal district of Pinheiro, Maranhão State, Brazil, were studied, considering their variety, relative abundance, seasonal fluctuation, preference by the peri and intra domiciles as well as the hours of hematophagism. The females were captured using human bait, on a monthly basis from May/1998 to April/1999, from 6 p.m. to 6 a.m. A total of 1,321 specimens of 10 species were captured, all belonging to the subgenus Nyssorhynchus. The most frequent species were A. argyritarsis (62%), A. darlingi (21.7%), A. albitarsis (4.5%), A. galvaoi (4.0%), A. triannulatus (3.1%) and A. evansae (2.8%). The species A. nuneztovari, A. braziliensis, A. rondoni and A. strodei together represented 1.9%. The anophelines occurred all year round, with no significant difference in the number of specimens captured between the rainy (51.7%) and dry season (48.3%). The frequency of the females in the peridomicile was significantly higher (p < 0.01) (82%), than in the intradomicile (18%), preferring to suck blood at dusk and in the first hours of the night.


Asunto(s)
Anopheles/clasificación , Fenómenos de Retorno al Lugar Habitual , Animales , Brasil , Enfermedades Endémicas , Humanos , Malaria/epidemiología , Densidad de Población
7.
Rev Soc Bras Med Trop ; 30(2): 107-11, 1997.
Artículo en Portugués | MEDLINE | ID: mdl-9148332

RESUMEN

Seven species belonging the subgenus Nyssorhyncus were found. Anopheles (N.) darlingi, the principal vector of human malaria, was the most abundant (53.1%) followed by A. (N.) evansae (21.0%, A. (N.) triannulatus (17.4%) e A. (N.) nuñeztovari (4.8%). The others, A. (N.) argyritarsis. A. (N.) oswaldoi and A. (N.) rangeli, were less frequently found, representing only 3.7% of the total sample. The anophelines were most frequent in both the extra (51.7%) and peridomiciles (45.7%). The intradomicile was visited by some specimens of the A. (N.) darlingi and A. (N.) evansae (active in both the rain and dry seasons, especially in the former, when the malaria reached high levels of transmission.


Asunto(s)
Anopheles/clasificación , Animales , Anopheles/fisiología , Brasil , Conducta Alimentaria , Humanos , Densidad de Población , Estaciones del Año
8.
Rev Soc Bras Med Trop ; 32(3): 247-53, 1999.
Artículo en Portugués | MEDLINE | ID: mdl-10380563

RESUMEN

This study lists 32 species of sand flies, 1 of them belonging to the genus Brumptomyia and 31 to the genus Lutzomyia, distributed among the following subgenera: Psychodopygus (6), Nyssomyia (5), Pressatia (3), Evandromyia (2), Psathyromyia (2), Sciopemyia (2), Lutzomyia (1), Micropygomyia (1), Viannamyia (1), and the groups Oswaldoi (5) and Migonei (3). The sand flies were captured in the wild (forest) and in peridomicile (pigpen, hen house and stable) and intradomicile (bedroom) areas from 06:00 PM to 06:00 AM, once a month, for 4 years on the Island of São Luis, Maranhão. All species sampled were present in the forest. Among them, 16 were found in the peridomicile, while 11 were found inside the houses. A total of 22,581 specimens were captured, 65.1% of them in the peridomicile, 17.5% in the forest and 17.4% in the intradomicile. The most common species was Lutzomyia longipalpis (66.4% of the captured specimens), followed by Lutzomyia whitmani (24%) and Lutzomyia evandroi (5.9%). The remaining 29 species represented 3.7% of the total sample.


Asunto(s)
Psychodidae , Animales , Brasil , Psychodidae/clasificación , Salud Rural
9.
Rev Soc Bras Med Trop ; 33(1): 11-9, 2000.
Artículo en Portugués | MEDLINE | ID: mdl-10881113

RESUMEN

In this study the diversity of the species and relative abundance of the sand flies in the Amazonian community of Lagoas, in Buriticupu, Maranhão State, was determined. The study consisted of adult sandflies captured with CD light-traps, Shannon-trap and manual aspiration tube, between 18 PM and 6 AM, once a month, from December/95 to January/97, in a forest fragment and in the domestic environment (peri and intra). In all, 9,393 specimens were captured (4,302 males and 5,140 females) distributed among 38 species (1 Brumptomyia and 37 Lutzomyia). The diversity and abundance of species was higher in the forest, followed by the peri and intra. The predominance in the wild ambient is a consequence of the potentialities found in the remaining fragments of the forest which have survived the lumber yard exploitation and agricultural activities. In the forest environment Lutzomyia whitmani (64.9%), L. migonei (27%) and L. serrana (3.6%) were the most frequent species. In the peri and intra domicile L. evandroi predominated (55.4% and 97.9%). The species, L. whitmani (33.4%) and L. migonei (6.4%), were important in the peri domicile. The peridomestic habit of 7.7% of the sand flies showed the greatest epidemiologic importance, due to the existence of patients with leishmaniasis ulcers, who believe they were infected near their habitations.


Asunto(s)
Insectos Vectores/clasificación , Psychodidae/clasificación , Animales , Brasil , Distribución de Chi-Cuadrado , Ecosistema , Femenino , Masculino , Densidad de Población , Árboles
10.
Rev Soc Bras Med Trop ; 31(3): 279-88, 1998.
Artículo en Portugués | MEDLINE | ID: mdl-9612019

RESUMEN

A comparative study on children aged 0-15 years, with American tegumentary leishmaniasis (ATL), in the endemic regions of Buriticupu (MA) and Corte de Pedra (BA), whereby 214 cases were detected between 1982 and 1993, 78 (36.4%) of them originated from Corte de Pedra and 136 (63.6%) from Buriticupu. In Corte de Pedra, most cases were observed in patients aged between 0-5 years. Twenty nine (37.2%) cases; 62% of those were male. In the Buriticupu region, 88 (64.7%) cases occurred in patients of 11-15 years of age, where in 73.8% consisted of male. In both researched regions, brunetts were predominant, with a ratio of 65.4% in Corte de Pedra and 75% in Buriticupu. Twenty six (33.3%) children in the village of Corte de Pedra were farmers, predominantly male (57.7%), generating statistical significance (chi 2 = 11.21). Twenty one (80.8%) farmers were aged 11-15 years. Thirty seven and a half per cent of the children from Buriticupu were students, however, 41 (30.2%) were farmers, representing 39 (44.3%) cases; all of them male. Both in Buriticupu and Corte de Pedra, the unique wound was predominant, corresponding to 57.7% and 53.7%, respectively. The wounding time stood out from one to three months, with 45 (69.2%) cases in Corte de Pedra and 73 (61%) in Buriticupu (chi 2 = 11.82). As to the wound locations, it has been observed that they were most constantly present on the lower limbs, with 77.2% in Corte de Pedra and 58.9% in Buriticupu (chi 2 = 27.9). The cutaneous case mostly found in Corte de Pedra was the ulcerous one (91%). IDRM was positive in 61 (78.2%) children originated from Corte de Pedra, wherein no statistical difference was detected between age ratio and positivity of the test (chi 2 = 0.0669).


Asunto(s)
Leishmaniasis Cutánea/epidemiología , Adolescente , Brasil/epidemiología , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino
11.
Cad Saude Publica ; 17(1): 221-7, 2001.
Artículo en Portugués | MEDLINE | ID: mdl-11241945

RESUMEN

This article presents the hourly and seasonal distribution of the Lutzomyia longipalpis sand fly captured on São Luís Island, Maranhão State. A total of 11,200 specimens were captured during monthly use of CDC light traps indoors and in animal sheds, between 6:00 PM and 6:00 AM, in 1996 and 1997. The sand fly behaved as an annual species, with a high frequency year-round, while it was most abundant during the rainy season (57.2%) as compared to the dry season (42.8%). The highest frequencies during the rainy season occurred in January and April and in the dry season in July and November. The species was found all night long, mainly between 6:00 PM and 10:00 PM in animal sheds and between 8:00 PM and 2:00 AM indoors.


Asunto(s)
Insectos Vectores/fisiología , Psychodidae/fisiología , Estaciones del Año , Animales , Brasil , Femenino , Vivienda , Humedad , Masculino , Temperatura , Factores de Tiempo
12.
Cad Saude Publica ; 16(1): 265-70, 2000.
Artículo en Portugués | MEDLINE | ID: mdl-10738174

RESUMEN

This paper analyzes the wealth of species, relative abundance, seasonal fluctuation, and nocturnal activity of sandflies. The field survey was conducted in a "capoeira" (secondary forest) area in the county of Paço do Lumiar, Maranhão, where cutaneous and transmission of visceral leishmaniasis frequently occurs. Sandflies were captured by CDC-type light traps from 6:00 PM to 6:00 AM, once a month, from March 1997 to February 1998. A total of 489 specimens were collected (251 males and 238 females), distributed among 10 species: Lutzomyia antunesi (45.19%), Lutzomyia whitmani (29.4%), Lutzomyia longipalpis (7.56%), Lutzomyia sordelli (6.34%), Lutzomyia flaviscutellata (4.5%), Brumptomyia avellari (4.09%), Lutzomyia evandroi (1.85%), Lutzomyia umbratilis (0.61%), Lutzomyia corossoniensis (0.41%), and Lutzomyia trispinosa (0.41%). The sandflies were present year round, with higher abundance during the rainy season. They were present in all intervals studied, with the highest frequency between 12:00 PM and 1:00 AM (31%).


Asunto(s)
Insectos Vectores/clasificación , Leishmaniasis Cutánea/transmisión , Psychodidae/clasificación , Animales , Brasil , Femenino , Masculino , Densidad de Población , Dinámica Poblacional , Estaciones del Año
13.
Cad Saude Publica ; 15(3): 477-86, 1999.
Artículo en Portugués | MEDLINE | ID: mdl-10502143

RESUMEN

Dengue and Aedes aegypti are widespread in the State of Maranhão. During 1995, 87 of the 136 of the State's counties, including 176 towns and 480,687 households, were studied, of which 30 counties (34. 4%), 118 towns (67.0%) and 10,357 households (2.1%) were positive for Aedes aegypti. The positive counties are distributed as follow: 3 on São Luís Island, 7 in the Amazonia of Maranhão, 12 in the southern zone of the cerrados or savannas, and 5 in the mixed forest/savanna/palm grove zone. One positive county for Ae. aegypti was located in each of the following: alluvial fields, forest/palm grove, and sand dune/shoals areas. The Ae. aegypti-positive household rates were higher in the Amazonia of Maranhão (3.5%) and on São Luís Island (2.5%), because they are the most heavily traveled migratory and trade routes between Maranhão and neighboring states and are also the State's main economic centers. Household infestation rates for Ae. aegypti and reported dengue case rates were higher during the rainy season, showing the importance of rain in forming prime breeding sites for Aedes and spreading dengue.


Asunto(s)
Aedes , Dengue/epidemiología , Insectos Vectores , Animales , Brasil/epidemiología , Humedad , Características de la Residencia
14.
Cad Saude Publica ; 15(3): 623-30, 1999.
Artículo en Portugués | MEDLINE | ID: mdl-10502159

RESUMEN

This article presents a list of ten sandfly species from the genus Lutzomyia França, 1924 found in the counties of Aldeias Altas, Capinzal do Norte, Caxias, Codó, Coelho Neto, Timbiras, Timon and Tuntum in northeastern Maranhão, Brazil. Presence of sandflies was associated with cases of visceral and cutaneous leishmaniasis. Some 377 specimens were captured indoors with CDC light traps and 1491 specimens in the peridomicile. The species were: Lutzomyia cortelezii, Lutzomyia evandroi, Lutzomyia goiana, Lutzomyia intermedia, Lutzomyia lenti, Lutzomyia longipalpis, Lutzomyia longipennis, Lutzomyia squamiventris, Lutzomyia termitophila and Lutzomyia whitmani. The most abundant species was L. longipalpis (67. 4% and 70.2%) followed by L. whitmani (31.0% and 24.7%). L. longipalpis was captured both indoors and outdoors in all the months studied.


Asunto(s)
Enfermedades Endémicas , Insectos Vectores , Psychodidae/clasificación , Animales , Brasil/epidemiología , Leishmaniasis Cutánea/epidemiología , Leishmaniasis Visceral/epidemiología , Estaciones del Año
15.
Rev Saude Publica ; 33(6): 535-41, 1999 12.
Artículo en Portugués | MEDLINE | ID: mdl-10689368

RESUMEN

INTRODUCTION: The study of the seasonal fluctuation, nocturnal activity, relative abundance and the richness of Anopheles species in anthropic environment is essential to the understanding of the their bioecology and to the surveillance program of malaria control. METHODS: The Anopheles species were studied from 6 P.M. to 6 A.M., once a month, for one year, from October 1996 to September 1997, in the municipal district of Raposa, of the São Luís island, Maranhão state. The basic method was the capture of female specimens on human baits in peri and intradomicile sites by means of aspiration tube and guided luminous focus. RESULTS: A total of 1.407 specimens were collected and distributed as follow: Anopheles aquasalis (82% of the sample), Anopheles galvaoi (10,2%), Anopheles albitarsis (6,4%), Anopheles evansae, Anopheles nuneztovari, and Anopheles triannulatus davisi (the last three represented together 1, 4%). The anophelines occurred all year round, mainly in the rainy period, being more frequent in the intra (75,3%) than in the peridomicile site (24,7%), showing a clear preference to suck blood in the evening. CONCLUSION: The behavioural variation of Anopheles shows that the different species are becoming adapted to closeness to human habitations, in the rural zone of the São Luis island.


Asunto(s)
Anopheles/fisiología , Ecosistema , Insectos Vectores/fisiología , Malaria/transmisión , Animales , Anopheles/clasificación , Conducta Animal , Brasil/epidemiología , Enfermedades Endémicas , Femenino , Humanos , Malaria/epidemiología , Periodicidad , Estaciones del Año
16.
Rev Port Cardiol ; 8(4): 313-21, 1989 Apr.
Artículo en Portugués | MEDLINE | ID: mdl-2698705

RESUMEN

Radioisotopic cardiac studies became, on the last decade, one of the more useful non-invasive methods for the diagnostic evaluation and follow-up of patients with heart disease. Such a contribution of nuclear cardiology is specially noticeable on ischemic heart disease: radionuclide angiography (RNA) allows quantification of left and right ventricular dysfunction, and therefore stands as an ideal technique for the prognostic approach of congestive heart failure. As to diagnosis, RNA is useful in the analysis of regional wall motion abnormalities of ischemic heart disease and detection of ventricular aneurysms. Clinical examples are given of these specific situations. In dilated cardiomyopathies RNA gives not only a measure of ventricular dysfunction, but also a diagnostic information, often definitive, of the diffuse involvement of all left ventricle, and commonly of the right ventricle. Ischemic heart disease, on the other hand, displays different degrees of segmental wall motion impairment together with areas of normal contractility. These aspects are documented with cases of our Registry. Also discussed is the inotropic stimulation technique for the evaluation of the functional reserve of left ventricle in patients with severe rest L.V. dysfunction. Focus is given to the clinical value of isotopic studies for the quantification of valvular regurgitations and pre-operative serial studies in order to define an optimum surgical timing. An attempt is done to grade the practical importance of the different exams of Nuclear Cardiology on the diagnostic and prognostic evaluation on heart disease patients, with a cost benefit relation perspective and comparing with other methods, classic of recent ones, available for the management of patients with heart failure.


Asunto(s)
Cardiomiopatía Dilatada/diagnóstico por imagen , Enfermedad Coronaria/diagnóstico por imagen , Insuficiencia Cardíaca/diagnóstico por imagen , Cardiomiopatía Dilatada/fisiopatología , Enfermedad Coronaria/fisiopatología , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/fisiopatología , Enfermedades de las Válvulas Cardíacas/diagnóstico por imagen , Enfermedades de las Válvulas Cardíacas/fisiopatología , Prótesis Valvulares Cardíacas , Humanos , Angiografía por Radionúclidos/métodos , Volumen Sistólico
17.
Rev Port Cardiol ; 9(1): 41-9, 1990 Jan.
Artículo en Portugués | MEDLINE | ID: mdl-2328137

RESUMEN

AIMS: To study by equilibrium radionuclide angiography (ERNA) the cardiac inotropic reserve after a myocardial infarction, and to evaluate its prognostic value. DESIGN: Patients in a chronic status of a myocardial infarction were studied by ERNA at a basal state and after stimulation with epinephrine, in the same session. Left ventricle (LV) functional abnormalities, global and regional, were evaluated. A 3-to-5 years follow-up was done. PATIENTS AND METHODS: Twenty five patients with a post myocardial infarction were included: 19 with an anterior infarction, 2 with an inferior and 4 with a combined one. All patients had LV dysfunction evaluated by Echocardiogram at hospital discharge. Global and regional LV function were studied by ERNA before and after inotropic stimulation, using increasing doses of epinephrine from 4.8 to 12 micrograms/minute. Heart rate and blood pressure were monitored. ERNA acquisition were done on left oblique best-septal and lateral views, over 400 cardiac cycles, using a Gama-camera GE 400AC. Three groups of patients were considered, according with the change of LV global ejection fraction: increments greater than 2%--group A (positive response); changes between +2% and -2% - group B; decreases greater than 2%--group C (negative response). During a 3 to 5 years follow-up, the incidence of major cardiac events was analysed: cardiovascular mortality, angina, left ventricle failure, myocardial reinfarction and coronary artery by-pass graft surgery. RESULTS: LV global function-Inotropic stimulation was done with an average perfusion time of 30.8 minutes, with total doses of epinephrine between 176 and 660 ng. No significant changes of heart rate (5%) or blood pressure (5.3%) occurred. Basal LV global ejection fraction (EF) was 29.2%. Only 2 patients had a normal LV ejection fraction; 14 patients had a severe LV dysfunction (EF less than 30%) and 9 had a moderate reduction of ejection fraction (EF between 30% and 45%). From the 14 patients with EF less than 30%, twelve had an involvement of the LV anterior wall. After stimulation EF value ineditreased in 9 and decreased in one patient. From the 11 patients with EF greater than 30%, 6 experienced a increase of EF and 3 decreased of EF after stimulation. REGIONAL WALL MOTION: Group A--15 patients--75 segments. In this group 39 segments were related to necrotic ECG localization, and 79% of them contributed to EF increase after stimulation. Forty-one segments were not involved by necrosis, and 78% had a positive contribution to EF increase. Six patients had all LV segments contributing to the EF increase after stimulation. The other 9 patients, had 13 segments not responding to stimulation (EF increments greater than 2%): 5 of them were segments related to ECG site of infarction. Group B--6 patients--30 segments. Five patients had 9 segments with a positive contribution to EF after inotropic stimulation.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Epinefrina/farmacología , Contracción Miocárdica/efectos de los fármacos , Infarto del Miocardio/fisiopatología , Adulto , Anciano , Enfermedad Crónica , Enfermedad Coronaria/fisiopatología , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estimulación Química , Volumen Sistólico/efectos de los fármacos
18.
Rev Port Cardiol ; 20 Suppl 5: V-79-96; discussion V-97-8, 2001 May.
Artículo en Portugués | MEDLINE | ID: mdl-11515305

RESUMEN

The concept of left ventricular aneurysm has been a subject of controversy and it's not yet completely settled. This has some implications on the patients selection for surgery and explains the various non-invasive methods so far developed for the clinical assessment of patients with ventricular aneurysms. Seventy-one patients with ischemic heart disease, 65 with recent myocardial infarction, were studied by equilibrium radionuclide angiography (ERNA) in order to define left ventricular wall motion abnormalities. One hundred ERNA were undertaken, through the usual erytrocites in vivo labelling technic, employing a GE 400 T Gama-Camera GP. Image acquisition was through 400 cardiac cycles, on LAO (30 and 60 degrees) and left lateral. PAGE protocol was employed. Fourier transform was used in the present work to obtain phase and amplitude images, which actually became the main criteria to define aneurysmatic areas. Global ejection fraction, regional wall motion and regional ejection fraction were other parameters investigated. Wall motion abnormalities have been identified in all the 65 patients having suffered a myocardial infarction. Extensive areas of akinesia or localized dyskinesia were present in 40 patients (16.5%), while remainder 25 had just localized hypoakinesia. Phase image enabled the selection of LV areas of contraction delay in 19 of the 40 patients with extensive wall motion abnormalities (Group I). In such Group I we could identify an LV area with contrasting colour, defining the aneurysmatic LV portion. In the order 21 patients with extensive akinesia, no significant changes of colour were present on ventricular phase image (Group II) meaning absence of aneurysm. No phase disturbances were seen in the remainder 25 patients with MI (Group III) and the 6 patients with CAD without MI had normal phase images (Group IV). The percentage of akinetic segments was 39.1 and 35.4 in Group I and II, respectively (p = .53) while it was significantly lower in Group III 17.9%; p < .0001). LV ejection fraction was statistically different in the four groups considered (I = 30.0% +/- 3.7; II = 39.9% +/- 2.9; III = 49.0% +/- 2.5; IV = 62.0% +/- 3.2). The degree of phase delay in aneurysmatic zones was quantified by the phase histogram. Average value of phase for the left ventricle was 129.7 +/- 8.4 degrees, and for the aneurysm it was 238.0 +/- 5.0 with an average phase delay of 104.8 +/- 4.1 degrees. The association of phase and amplitude images and the measurements of phase and amplitude values on the histograms allowed the distinction of akinetic aneurysm (phase delay and low amplitude) from the dyskinetic aneurysms (phase delay and high amplitude). Half of the isotopic diagnosis of aneurysms have been confirmed by classic contrast angiography, and a third of then have undergone surgery. The two dyskinetic aneurysms that have been submitted to aneurysmectomy had pos-operative improvement of LV function. On summary, phase and amplitude analysis by the Fourier method, which is independent of LV geometry, showed that LV regions with high phase values are associated with severe regional wall motion abnormalities and low ejections fractions. The definition of the sequence and amplitude of ventricular contraction allows the distinction of akinetic and dyskinetic aneurysms, anticipating the method as a valid contribution for the screening of patients likely to benefit from aneurysmectomy.


Asunto(s)
Análisis de Fourier , Imagen de Acumulación Sanguínea de Compuerta , Aneurisma Cardíaco/diagnóstico por imagen , Ventrículos Cardíacos , Infarto del Miocardio/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Aneurisma Cardíaco/etiología , Humanos , Masculino , Persona de Mediana Edad
19.
Rev Port Cardiol ; 8(1): 19-26, 1989 Jan.
Artículo en Portugués | MEDLINE | ID: mdl-2631811

RESUMEN

OBJECTIVE: To study the evolution of left ventricular (LV) function in the 1st year after acute myocardial infarction (MI) and to define its prognostic significance. DESIGN: Patients recovering from acute MI submitted to evaluation of LV function by equilibrium radionuclide angiography (RNA) at the time of discharge, three months later and at 12 months of follow-up. PATIENTS AND METHODS: 93 patients suffering an acute transmural MI were submitted to equilibrium RNA. Studies were taken at time of discharge, 3 and 12 months of follow-up. 19 patients had just the 1st study; in 14 the one year follow-up study was not performed. The other 60 include the group submitted to 1 year follow-up. We used the technic of labelled erytrocites in vivo, with acquisition of the blood pool gated with EKG in left lateral. PAGE protocol from GE has been used for processing of images. RESULTS: Mean global ejection fraction (EF) was 20.6 +/- 8.5% for anterior MI with LV failure and 40.2 +/- 14.5% for those without failure; in inferior MI it was 49.9 +/- 12.3% and for combined MI 30.3 +/- 9.5%. The differences between these values are statistically significant. For the 56 patients in which the 1st and 2nd examination were taken we found no significant differences between the mean values for global EF in the 4 groups previously considered. Conversely, we couldn't find a significant difference between the mean EF in the 4 groups, when we compared the values of early (1st and 2nd examinations) test with those of 12 months follow-up. 10 patients (10.8%) died in the 1 year follow-up. All had global EF lower than normal: 33% of deaths in the group with EF less than 20%; 14% in the subset with EF between 20 and 30%; 8% in the sub-group with EF between 30 and 45%. As far as regional motion is concerned we noticed that changes include both the necrotic and the spared areas. We didn't found significant differences between the contribution of necrotic and viable myocardium to the positive or negative variation of global EF, in the 4 groups of infarction considered. Apical segment seems to have an important contribution for global EF changes, both in anterior and inferior MI. CONCLUSION: In this group of patients with acute MI, followed for 12 months, we noticed a higher degree of LV dysfunction in the group of anterior MI. The values of LVEF measured early after the acute attach, usually at hospital discharge are stable along the follow-up, unless major cardiac episodes develop. All the deaths along the one year follow-up had LV dysfunction with EF below 45%. Prognostic "quod vitam" worsened while EF decreased, with a death rate of 33% in the sub-group with global EF less than 20%, and 28% considering those with EF below 30%. In relation with regional motion we found that changes may be elicited both in the necrotic and spared segments. We emphasize the contribution of the apical area to the changes in global EF.


Asunto(s)
Imagen de Acumulación Sanguínea de Compuerta , Infarto del Miocardio/fisiopatología , Volumen Sistólico , Adulto , Anciano , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/mortalidad
20.
Rev Port Cardiol ; 8(2): 95-101, 1989 Feb.
Artículo en Portugués | MEDLINE | ID: mdl-2631839

RESUMEN

OBJECTIVE OF THE STUDY: To compare ischemic changes (I) detected by Holter ECG (H ECG) to the myocardial perfusion defects found in 201 TI myocardial perfusion scintigraphy. DESIGN: 201 TI exercise test was made during the performance of a 24 hours H ECG. The validation of ST segment changes detected by H ECG during the exercise test was made on basis of reversible myocardial perfusion defects (RPD) detected on 201 TL and a relation between ST segment changes detected during the remaining 24 hours recording period and 201 TI (TI) RPD was established. SETTING: The patients (pt) included in the study have come from Cardiology and Heart Surgery Clinics of a Central teaching hospital. MATERIAL AND METHODS: 20 pt with a high coronary artery disease prevalence have been submitted to a two lead (V5 and aVF) 24 hour H ECG during which they have performed a symptom limited bicycle exercise test followed by an injection of 201 TI with acquisition 5 minutes later. Ischemic episodes detected on H ECG were quantified and their relation with heart rate and symptoms was established. As far as 201 TI studies are concerned the fixed and reversible perfusion defects as well as their location were evaluated. RESULTS: 1. H ECG: 6 pt (30%) presented ST changes on H ECG during the exercise test and a total of 9 pt (45%) had ST changes during exercise and during the remaining period of H ECG. 2. TI: 19 pt presented perfusion defects images (fixed in 7, reversible in 14, both kinds of defects in 7). 3. H ECG validation: H ECG during exercise presented I in 6 out of 14 pt with RPD on TI (sensitivity = 43%). Six of these 8 pt, with negative H and positive TI, had a chronic myocardial infarction. All the 6 pt with negative TI had negative H ECG (specificity = 100%). 4. H ECG TI comparison: 7 (50%) of the 14 pt with RPD had ST changes on 24 hrs H ECG. Seven of 11 pt with negative H ECG had RPD in TI. Two pt with negative TI had positive H ECG. These 2 pt had during H ECG a higher heart rate (HR) than the HR recorded during the exercise test. CONCLUSIONS: 1. In pt with known CAD, TI has a high sensitivity and specificity to show perfusion defects. 2. Considering TI as gold standard, H ECG showed to be a useful method to detect I in the studied population (sens. = 43%; spec. = 100%). 3. H ECG revealed to be an important diagnostic tool in detecting additional I episodes beyond the ones recorded during TI exercise test.


Asunto(s)
Enfermedad Coronaria/diagnóstico , Electrocardiografía Ambulatoria , Radioisótopos de Talio , Adulto , Anciano , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/fisiopatología , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cintigrafía
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