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1.
Rapid Commun Mass Spectrom ; 30(1): 29-44, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26661968

RESUMO

RATIONALE: Stable isotope ratios (δ(13)C and δ(15)N values) provide a unique perspective into the ecology of animals because the isotope ratio values of consumers reflect the values in food. Despite the value of stable isotopes in ecological studies, the lack of species-specific experimentally derived diet-tissue discrimination factors (DTDFs) and turnover rates limits their application at a broad scale. Furthermore, most aquatic feeding experiments use temperate, fast-growing fish species and few have considered medium- to large-sized adults with low growth rates from tropical ecosystems. METHODS: A controlled-diet stable isotope feeding trial was conducted over a 196-day period for the adult predatory reef fish leopard coralgrouper (Plectropomus leopardus). This study calculated δ(13)C and δ(15)N DTDFs and turnover rates in five tissues (liver, plasma, red blood cells (RBC), fin, and muscle) using a continuous flow isotope ratio mass spectrometer equipped with an elemental analyzer. In addition, the effect of chemical lipid extraction (LE) on stable isotope values was examined for each tissue. RESULTS: Turnover was mainly influenced by metabolism (as opposed to growth) with LE δ(15)N half-life values lowest in fin (37 days) and plasma (66 days), and highest in RBC (88 days) and muscle (126 days). The diet-tissue discrimination factors for δ(15)N values in all tissues (Δ(15)N: -0.15 to 1.84‰) were typically lower than commonly reported literature values. Lipid extraction altered both δ(15) N and δ(13)C values compared with untreated samples; however, for the δ(15)N values, the differences were small (mean δ(15)N(LE-Bulk) <0.46‰ in all tissues). CONCLUSIONS: This study informs future interpretation of stable isotope data for medium- to large-sized fish and demonstrates that DTDFs developed for temperate fish species, particularly for δ(15)N values, may not apply to tropical species. Sampling of muscle and/or RBC is recommended for a relatively long-term representation of feeding habits, while plasma and/or fin should be used for a more recent indication of diet.


Assuntos
Isótopos de Carbono/análise , Isótopos de Carbono/metabolismo , Isótopos de Nitrogênio/análise , Isótopos de Nitrogênio/metabolismo , Perciformes/metabolismo , Ração Animal , Animais , Dieta , Distribuição Tecidual
2.
J Fish Biol ; 88(3): 1149-74, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26806022

RESUMO

Two Australian endemic elasmobranchs, the Argus skate Dipturus polyommata and the eastern spotted gummy shark Mustelus walkeri, were collected from the by-catch of a prawn Melicertus plebejus trawl fishery off Queensland. Age and growth parameters were estimated from growth band counts in vertebral sections of 220 D. polyommata and 44 M. walkeri. Dipturus polyommata males and females had an observed maximum age of 10 years and reached maximum sizes of 369 and 371 mm total length (LT ), respectively. Mustelus walkeri lived longer, with the oldest female aged 16 years and measuring 1050 mm stretched total length (LST ), and oldest male aged 9 years and 805 mm LST . Dipturus polyommata grew relatively fast with a von Bertalanffy growth completion parameter of k = 0·208 year(-1) with males reaching maturity at 4·0 years (c. 278 mm LT ) and females at 5·1 years (c. 305 mm LT ). Mustelus walkeri grew more slowly with k = 0·033 year(-1) with males estimated to mature at 7-9 years (670-805 mm LST ) and females at 10-14 years (833-1012 mm LST ). Length at birth inferred from neonate D. polyommata was 89-111 mm LT while for M. walkeri it was estimated to be 273 LST based on the value of L0 from the von Bertalanffy growth model. Both species appeared to have continuous reproductive cycles and low fecundity with an average ovarian fecundity of eight follicles for D. polyommata and a litter size of five to seven pups for M. walkeri. Based on these life-history traits, D. polyommata is more resilient to fishing pressure than M. walkeri.


Assuntos
Tubarões/fisiologia , Rajidae/fisiologia , Animais , Austrália , Tamanho Corporal , Feminino , Fertilidade , Pesqueiros , Masculino , Queensland , Maturidade Sexual , Tubarões/crescimento & desenvolvimento , Rajidae/crescimento & desenvolvimento , Coluna Vertebral/anatomia & histologia
3.
J Fish Biol ; 86(5): 1567-86, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25846994

RESUMO

This study used stable-isotope analysis to define the nearshore regional residency and movements of the small-bodied Australian sharpnose shark Rhizoprionodon taylori. Plasma and muscle δ(13) C and δ(15) N of R. taylori were collected from across five embayments and compared with values of seagrass and plankton from each bay. Linear distances between adjacent bays ranged from 30 to 150 km. There was a positive geographic correlation between R. taylori tissue and environmental δ(13) C values. Populations with the highest tissue δ(15) N were collected from bays that had the highest environmental δ(15) N values. These results suggest that R. taylori did not forage more than 100 km away from their capture location within 6 months to 1 year. The successful application of isotope analysis to define R. taylori movement demonstrates that this technique may be used in addition to traditional methods to study the movement of sharks, even within similar habitats across regionally small spatial scales (<100 km).


Assuntos
Ecossistema , Atividade Motora , Tubarões/fisiologia , Animais , Teorema de Bayes , Baías , Isótopos de Carbono/análise , Isótopos de Nitrogênio/análise , Queensland
4.
J Fish Biol ; 84(5): 1340-53, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24702252

RESUMO

Estimates of life-history parameters were made for shark-like batoids of conservation concern Rhynchobatus spp. (Rhynchobatus australiae, Rhynchobatus laevis and Rhynchobatus palpebratus) and Glaucostegus typus using vertebral ageing. The sigmoid growth functions, Gompertz and logistic, best described the growth of Rhynchobatus spp. and G. typus, providing the best statistical fit and most biologically appropriate parameters. The two-parameter logistic was the preferred model for Rhynchobatus spp. with growth parameter estimates (both sexes combined) L(∞) = 2045 mm stretch total length, LST and k = 0·41 year⁻¹. The same model was also preferred for G. typus with growth parameter estimates (both sexes combined) L∞ = 2770 mm LST and k = 0·30 year⁻¹. Annual growth-band deposition could not be excluded in Rhynchobatus spp. using mark-recaptured individuals. Although morphologically similar G. typus and Rhynchobatus spp. have differing life histories, with G. typus longer lived, slower growing and attaining a larger maximum size.


Assuntos
Envelhecimento , Tamanho Corporal , Elasmobrânquios/crescimento & desenvolvimento , Animais , Conservação dos Recursos Naturais , Feminino , Modelos Logísticos , Masculino
5.
J Fish Biol ; 83(5): 1401-6, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24580674

RESUMO

Baseline, post-angling and maximum attainable blood lactate concentrations were measured for the fishery species redthroat emperor Lethrinus miniatus to gain insight into the condition of fish released following c. 30 s angling and <45 s air exposure. Mean ± S.D. baseline blood lactate was 1·5 ± 0·6 mmol l⁻¹, which increased and plateaued around 6 mmol l⁻¹ at 15-30 min post-angling. These values were significantly lower than those obtained from fish maximally exhausted with a prolonged chase and air exposure protocol following capture (10·9 ± 1·8 mmol l⁻¹), suggesting that L. miniatus is not maximally exhausted during standard angling practices.


Assuntos
Comportamento Animal , Ácido Láctico/sangue , Perciformes/sangue , Estresse Fisiológico , Natação , Animais , Fadiga , Perciformes/fisiologia
6.
J Fish Biol ; 82(4): 1192-210, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23557299

RESUMO

This study examined the characteristics of a blacktip reef shark Carcharhinus melanopterus population in turbid coastal habitats through a multi-year fishery-independent sampling and tag-recapture programme. Results revealed a highly structured population comprised almost entirely of juveniles and adult females with individuals between 850 and 1050 mm total length effectively absent. Mature males were also rarely encountered with adult sex ratio highly biased towards females (female:male = 7:1). Mating scars were observed on adult females between December and April, and parturition was observed from December to March. Regression analysis showed that catch rates were significantly higher during the summer wet season between November and May. Recapture data suggested a highly resident population with a recapture rate of 21% and a mean recapture distance of 0·8 km. In addition, 33% of recaptured animals were captured multiple times, indicating long-term residency. Most recaptures were, however, of adults with few juveniles recaptured. Widespread sampling at the study site and in adjacent areas suggested that the population was highly localized to a specific bay. The bimodal and sex-segregated population structure observed here differs from previous reports for this species, and in combination with reproductive observations, suggests population structuring to facilitate reproductive and recruitment success. These data also highlight the potential ecosystem functions performed by coastal habitats in sustaining C. melanopterus populations.


Assuntos
Ecossistema , Razão de Masculinidade , Tubarões/fisiologia , Sistemas de Identificação Animal , Animais , Tamanho Corporal , Feminino , Masculino , Queensland , Estações do Ano
7.
J Fish Biol ; 82(3): 764-88, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23464543

RESUMO

Life-history characteristics of six tropical Lethrinus species sampled from the Great Barrier Reef World Heritage Area were compared. Two species groups were identified based on fork length (LF ): large species with maximum LF > 640 mm (longface emperor Lethrinus olivaceus, yellowlip emperor Lethrinus xanthochilus and spangled emperor Lethrinus nebulosus) and small species with maximum LF < 480 mm (Pacific yellowtail emperor Lethrinus atkinsoni, pink ear emperor Lethrinus lentjan and ornate emperor Lethrinus ornatus). Lifespan was not correlated with LF . Early growth for all species was rapid and similar during the first few years of life, but coefficients of the von Bertalanffy growth function varied considerably among species. Growth also differed between sexes for L. atkinsoni. Reproductive characteristics varied among species, with peak periods of spawning occurring in November to December for L. atkinsoni, July to August for L. nebulous, September to October for L. olivaceus and a protracted season for L. lentjan, although fewer samples were available for the last two species. Sex-specific LF and age distributions and gonad histology of L. lentjan were suggestive of a functional protogynous reproductive pattern, as observed in other lethrinids. Gonad histology indicated non-functional protogynous hermaphroditism for L. atkinsoni and L. nebulosus. The diversity of life histories among these closely related species emphasizes the difficulty in devising single management strategies appropriate for multi-species fisheries and illustrates the importance of understanding species-specific life histories to infer responses to exploitation.


Assuntos
Perciformes/fisiologia , Reprodução , Distribuição por Idade , Animais , Austrália , Tamanho Corporal , Feminino , Masculino , Perciformes/crescimento & desenvolvimento , Estações do Ano , Especificidade da Espécie
8.
Rev Fish Biol Fish ; 33(2): 475-499, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36404946

RESUMO

Shark depredation is a complex social-ecological issue that affects a range of fisheries worldwide. Increasing concern about the impacts of shark depredation, and how it intersects with the broader context of fisheries management, has driven recent research in this area, especially in Australia and the United States. This review synthesises these recent advances and provides strategic guidance for researchers aiming to characterise the occurrence of depredation, identify the shark species responsible, and test deterrent and management approaches to reduce its impacts. Specifically, the review covers the application of social science approaches, as well as advances in video camera and genetic methods for identifying depredating species. The practicalities and considerations for testing magnetic, electrical, and acoustic deterrent devices are discussed in light of recent research. Key concepts for the management of shark depredation are reviewed, with recommendations made to guide future research and policy development. Specific management responses to address shark depredation are lacking, and this review emphasizes that a "silver bullet" approach for mitigating depredation does not yet exist. Rather, future efforts to manage shark depredation must rely on a diverse range of integrated approaches involving those in the fishery (fishers, scientists and fishery managers), social scientists, educators, and other stakeholders.

9.
J Fish Biol ; 80(4): 767-84, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22471798

RESUMO

An array of acoustic receivers deployed in Cleveland Bay, north Queensland, Australia, passively tracked 20 adult spottail sharks Carcharhinus sorrah over 2 years (2009-2010) to define patterns in movement and habitat use. Individuals were present in the study site for long periods, ranging from 8 to 408 days (mean = 185). Size and location of home ranges did not vary over time. A high level of segregation occurred among C. sorrah, with individuals using different types of habitat and showing strong attachment to specific regions. The depth of habitat individuals used varied between sexes. Males tended to use a narrow range of habitat depths within the study site (2·8-6·0 m), whereas females used shallower habitats (1·4-6·2 m) and displayed a seasonal shift in the depth of habitat used. Mean monthly habitat depth used varied by as much as 2 m for females, with individuals using shallower habitats during the winter months. Long-term presence and consistent home ranges suggest that Cleveland Bay provides important habitat for C. sorrah. By defining patterns in the use of nearshore habitats for C. sorrah, this study improves the understanding of the movement and habitat use of smaller-bodied coastal sharks and may help provide guidance for the management of their populations.


Assuntos
Ecossistema , Tubarões/fisiologia , Animais , Comportamento Animal , Feminino , Masculino , Queensland , Clima Tropical
10.
J Fish Biol ; 81(4): 1225-33, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22957866

RESUMO

Precaudal vertebral counts were used to distinguish between 237 morphologically similar Carcharhinus limbatus and Carcharhinus tilstoni and were congruent with differences in reproductive ecology between the species. In addition to differing lengths at maturity and adult body size, the two species had asynchronous parturition, were born at different sizes and the relative frequencies of neonates differed in two coastal nursery areas. Despite evidence that hybridization can occur, these differences suggest the species are largely reproductively isolated.


Assuntos
Ecologia , Reprodução/fisiologia , Tubarões/anatomia & histologia , Tubarões/fisiologia , Coluna Vertebral/anatomia & histologia , Animais , Austrália , Feminino , Masculino , Isolamento Reprodutivo , Especificidade da Espécie
11.
J Fish Biol ; 78(7): 2026-51, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21651548

RESUMO

The life histories of two globally endangered hammerhead sharks, Sphyrna lewini and Sphyrna mokarran, were examined using samples collected from a range of commercial fisheries operating along the east coast of Australia. The catch of S. lewini was heavily biased towards males, and there were significant differences in von Bertalanffy growth parameters (L(∞) and k) and maturity [stretched total length (L(ST)) and age (A) at which 50% are mature, L(ST50) and A(50)] between those caught in the tropics (L(∞) = 2119 mm, k = 0·163, L(ST50) = 1471 mm, A(50) = 5·7 years) and those caught in temperate waters (L(∞) = 3199 mm, k = 0·093, L(ST50) = 2043 mm, A(50) = 8·9 years). The best-fit estimates for a three-parameter von Bertalanffy growth curve fit to both sexes were L(∞) = 3312 mm, L(0) = 584 mm and k = 0·076. Males attained a maximum age of 21 years and grew to at least 2898 mm L(ST). The longevity, maximum length and maturity of females could not be estimated as mature animals could not be sourced from any fishery. Length at birth inferred from neonates with open umbilical scars was 465-563 mm L(ST). There was no significant difference in length and age at maturity of male and female S. mokarran, which reached 50% maturity at 2279 mm L(ST) and 8·3 years. Sphyrna mokarran grew at a similar rate to S. lewini and the best-fit estimates for a two-parameter von Bertalanffy equation fit to length-at-age data for sexes combined with an assumed mean length-at-birth of 700 mm were L(∞) = 4027 mm and k = 0·079. Females attained a maximum age of 39·1 years and grew to at least 4391 mm L(ST). The oldest male S. mokarran was 31·7 years old and 3691 mm L(ST). Validation of annual growth-band deposition in S. mokarran was achieved through a mark, tag and recapture study.


Assuntos
Espécies em Perigo de Extinção , Tubarões/fisiologia , Animais , Austrália , Tamanho Corporal , Feminino , Longevidade , Masculino , Reprodução , Fatores Sexuais , Maturidade Sexual , Tubarões/anatomia & histologia , Tubarões/crescimento & desenvolvimento
12.
Conserv Biol ; 24(5): 1212-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20337690

RESUMO

General consensus among scientists, commercial interests, and the public regarding the status of shark populations is leading to an increasing need for the scientific community to provide information to help guide effective management and conservation actions. Experience from other marine vertebrate taxa suggests that public, political, and media pressures will play an increasingly important part in setting research, management, and conservation priorities. We examined the potential implications of nonscientific influences on shark research. In particular, we considered whether lethal research sampling of sharks is justified. Although lethal sampling comes at a cost to a population, especially for threatened species, the conservation benefits from well-designed studies provide essential data that cannot be collected currently in any other way. Methods that enable nonlethal collection of life-history data on sharks are being developed (e.g., use of blood samples to detect maturity), but in the near future they will not provide widespread or significant benefits. Development of these techniques needs to continue, as does the way in which scientists coordinate their use of material collected during lethal sampling. For almost half of the known shark species there are insufficient data to determine their population status; thus, there is an ongoing need for further collection of scientific data to ensure all shark populations have a future. Shark populations will benefit most when decisions about the use of lethal sampling are made on the basis of scientific evidence that is free from individual, political, public, and media pressures.


Assuntos
Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Tubarões/fisiologia , Manejo de Espécimes/métodos , Manejo de Espécimes/veterinária , Animais , Dinâmica Populacional , Pesquisa , Especificidade da Espécie
13.
PLoS One ; 15(2): e0228280, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32107488

RESUMO

Stingrays are thought to play important ecological roles in coral reef ecosystems. However, little is known about juvenile stingray movement patterns and habitat use in coral reefs. This study used active acoustic telemetry to determine fine-scale diel movement patterns and habitat use of juvenile cowtail stingrays (Pastinachus ater) in a coral reef flat environment. Seven cowtail stingrays (4 males and 3 females) were manually tracked between April and December 2016. Each individual was tracked over 2 days, generating a total of 14 active tracks ranging from 4.91 to 9 h. Specimens moved at an average speed of 2.44 m min-1 ± 0.87 SE, with minimum distances travelled ranging from 546 to 1446 m. Tracking data showed that juvenile cowtail stingrays move in response to tidal cycles, moving faster and in straighter pathways during incoming and outgoing tides. Juvenile cowtail stingrays also showed a strong affinity to sand flat areas and mangrove edge areas. These areas provide food resources and potential refuges for juvenile rays to avoid predators. Coral reef flats were identified as secondary refuge for juveniles during the lowest tides. Future research is necessary to fully unveil the major drivers of juvenile cowtail stingray seasonal and ontogenetic movement patterns and habitat use within coral reef flat environments. This information is important to establish a full understanding of juvenile cowtail stingray ecology, but could also improve management and conservation policies.


Assuntos
Recifes de Corais , Rajidae/fisiologia , Animais , Comportamento Animal , Feminino , Masculino , Estações do Ano , Rajidae/crescimento & desenvolvimento
14.
Sci Rep ; 9(1): 9254, 2019 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-31239504

RESUMO

The elasmobranch bycatch of the Gulf of Papua Prawn Fishery is investigated in detail for the first time. Fisheries observers collected data on the elasmobranch bycatch from a total of 403 trawl sets (1,273 hrs) in the Gulf of Papua. A total of 40 species of elasmobranchs were recorded ranging in size from a 12 cm disc width stingray to a 350 cm total length sawfish. High mortality rates were recorded (>80%), attributed to the long trawl durations (up to 4 hours). The future inclusion of bycatch reduction devices would likely reduce the number of larger elasmobranchs being caught, based on evidence from the prawn trawl fisheries of northern Australia, and is being investigated by the PNG National Fisheries Authority. Differences in catch compositions were detected across the management zones as well as between the two monsoonal seasons (SE Monsoon and NW Monsoon). Increased monitoring and additional research is required and management plans should address the elasmobranch bycatch and in particular their high mortality rate.

15.
Sci Rep ; 7: 46061, 2017 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-28429742

RESUMO

Conservation and management of migratory species can be complex and challenging. International agreements such as the Convention on Migratory Species (CMS) provide policy frameworks, but assessments and management can be hampered by lack of data and tractable mechanisms to integrate disparate datasets. An assessment of scalloped (Sphyrna lewini) and great (Sphyrna mokarran) hammerhead population structure and connectivity across northern Australia, Indonesia and Papua New Guinea (PNG) was conducted to inform management responses to CMS and Convention on International Trade in Endangered Species listings of these species. An Integrated Assessment Framework (IAF) was devised to systematically incorporate data across jurisdictions and create a regional synopsis, and amalgamated a suite of data from the Australasian region. Scalloped hammerhead populations are segregated by sex and size, with Australian populations dominated by juveniles and small adult males, while Indonesian and PNG populations included large adult females. The IAF process introduced genetic and tagging data to produce conceptual models of stock structure and movement. Several hypotheses were produced to explain stock structure and movement patterns, but more data are needed to identify the most likely hypothesis. This study demonstrates a process for assessing migratory species connectivity and highlights priority areas for hammerhead management and research.

16.
J Am Coll Cardiol ; 13(2): 283-8, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2521500

RESUMO

Among 3,548 patients undergoing a percutaneous transluminal coronary angioplasty procedure, 714 had multilesion angioplasty (1,550 lesions) in a single session. Acute occlusion occurred in 22 patients (3.1%) and 29 lesions (1.9%). The patients were classified into a group undergoing multivessel angioplasty (348 patients, 785 lesions) and a group undergoing multilesion single vessel angioplasty (366 patients, 765 lesions). The rate of acute occlusion was similar in both patient groups. The multivessel angioplasty group had a 2.9% rate per patient (n = 10) and a 1.7% rate per vessel; the multilesion single vessel group had a 3.3% rate per patient (n = 12) and a 2.1% rate per lesion. Five of the 10 patients from the multivessel group with acute occlusion, but only 1 of the 12 patients with occlusion in the single vessel multilesion group, required emergency open heart surgery. No patient in either group died as a consequence of coronary angioplasty. Occlusion occurred during angioplasty in 15 of the 22 patients, and 1 to 24 h after angioplasty in 7 of 22 patients. In the group with multivessel angioplasty, acute occlusion during the procedure was mainly linked with hypotension during the second vessel dilation, whereas in this group with delayed vessel closure and in the multilesion single vessel group, existence of intimal tearing constituted the most important factor for acute occlusion (12 of 16 patients). Closure of vessel per major coronary system was evenly distributed in the multivessel group, whereas significantly more left circumflex vessels closed in the single vessel multilesion group (6.1% versus 1.3% in the left anterior descending coronary artery and 1.1% in the right coronary artery; p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Angioplastia com Balão , Doença das Coronárias/terapia , Doença Aguda , Adulto , Idoso , Angioplastia com Balão/efeitos adversos , Doença das Coronárias/patologia , Vasos Coronários/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva
17.
J Am Coll Cardiol ; 24(1): 74-80, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8006285

RESUMO

OBJECTIVES: We attempted to develop a statistical model to facilitate risk stratification for long-term outcome after elective coronary angioplasty. BACKGROUND: Our understanding of factors related to long-term outcome after coronary angioplasty is limited. Adequate assessment of risk indexes could potentially lead to more appropriate use of percutaneous revascularization. METHODS: We studied 5,000 consecutive patients and assessed 19 clinical and anatomic variables as predictors of long-term event-free survival. Events were defined as death of any cause, myocardial infarction, bypass surgery or repeat percutaneous transluminal coronary angioplasty. Cox proportional hazards models were used to develop an equation for predicting event-free survival in a subset of 4,000 patients. The equation was validated with the remaining 1,000 patients. Variables that were significantly associated with an adverse outcome in the multivariate model included age > 60 years, extent of disease, Canadian Cardiovascular Society functional class, previous coronary angioplasty, male gender, history of diabetes mellitus, history of hypertension and history of congestive heart failure. RESULTS: The statistical model was used to develop a simplified scoring system, and the patients were assigned to three risk subgroups. Event-free survival curves for the three groups were significantly different (p = 0.0001). High risk patients had worse outcomes for each of the end points compared with low and moderate risk patients (p < 0.02). CONCLUSIONS: We demonstrated that clinical and anatomic variables can be used to risk-stratify long-term outcome after angioplasty, that a simplified scoring system can be used for risk stratification and that high risk patients have a low event-free survival.


Assuntos
Angioplastia Coronária com Balão/estatística & dados numéricos , Idoso , Angioplastia Coronária com Balão/mortalidade , Doença das Coronárias/mortalidade , Doença das Coronárias/terapia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Análise Multivariada , Ohio/epidemiologia , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
18.
J Am Coll Cardiol ; 24(1): 46-54, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8006282

RESUMO

OBJECTIVES: To determine whether excision of complex, ulcerated plaque improves the risk of patients with unstable angina to the level of those with stable angina, the results of directional coronary atherectomy were compared in patients with these two syndromes. BACKGROUND: The procedural results of angioplasty in the setting of unstable angina are not as favorable as those observed for chronic stable angina, presumably because thrombus-associated plaque augments the risk of abrupt closure. METHODS: Two hundred eighty-seven consecutive patients who had undergone directional atherectomy for a single new stenosis were studied. Seventy-seven patients had stable angina (Group I); 110 patients had progressively worsening angina in the absence of rest or postinfarction angina (Group II); and 100 patients had rest or postinfarction angina, or both (Group III). RESULTS: Major ischemic complications (death, Q wave infarction, emergency bypass surgery) occurred more frequently in Group III (1.3% [Group I] vs. 0.9% [Group II] vs. 7% [Group III], p = 0.036). This difference was largely due to a higher incidence of emergency surgery in Group III (1.3% [Group I] vs. 0% [Group II] vs. 5% [Group III], p = 0.05). Clinical follow-up was obtained in 97% of successful procedures for a mean follow-up period of 22 months (range 9 to 52) and revealed a higher incidence of hospital admission for angina (p = 0.05) and a trend toward more bypass surgery (p = 0.09) and myocardial infarction (p = 0.16) in Group III. There was no difference in repeat percutaneous interventions among the three groups (range 19% to 24%, p = 0.75). CONCLUSIONS: These results show that the definition of unstable angina is important in determining the immediate outcome of directional atherectomy. In the absence of rest or postinfarction angina, the immediate results are not significantly different from those obtained in stable angina. Our results also suggest that both the immediate and short-term outcome in unstable angina are not greatly influenced by atherectomy but more so by the pathophysiology of unstable angina, which increases the complications of percutaneous interventions.


Assuntos
Angina Instável/cirurgia , Aterectomia Coronária , Análise de Variância , Angina Pectoris/complicações , Angina Pectoris/diagnóstico por imagem , Angina Pectoris/mortalidade , Angina Pectoris/cirurgia , Angina Instável/complicações , Angina Instável/diagnóstico por imagem , Angina Instável/mortalidade , Aterectomia Coronária/instrumentação , Aterectomia Coronária/métodos , Aterectomia Coronária/estatística & dados numéricos , Distribuição de Qui-Quadrado , Angiografia Coronária , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Ohio/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Recidiva , Análise de Sobrevida , Resultado do Tratamento
19.
J Am Coll Cardiol ; 26(4): 955-60, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7560623

RESUMO

OBJECTIVES: This study sought to evaluate the short-term results and long-term outcome of percutaneous revascularization of ostial saphenous vein graft stenoses in a large patient series. BACKGROUND: Previous studies have demonstrated that the results of balloon angioplasty for native coronary ostial stenoses are significantly worse than those for nonostial lesions. However, it is controversial whether interventions in patients with ostial saphenous vein grafts carry a similar prognosis. METHODS: We identified 68 consecutive patients with ostial (group I) and 72 consecutive patients with proximal, nonostial (group II) saphenous vein graft stenoses who underwent percutaneous angioplasty or directional atherectomy for a single new stenosis at the Cleveland Clinic between 1986 and 1992. RESULTS: Success was achieved in 61 patients (89.7%) in group I and 64 (88.9%) in group II (p = 0.88). There were no differences in major procedural complications (death, Q wave infarction and bypass surgery) between the two groups. At a mean (+/- SD) follow-up of 23 +/- 17 months, 36 patients (64%) in group I had one or more adverse events (death, infarction, repeat coronary revascularization or cardiac-related hospital admission) compared with 34 patients (58%) in group II (p = 0.87). Twenty-eight patients (50%) were angina free in group I compared with 33 (56%) in group II (p = 0.65). During the follow-up period in group I, 7 patients died (13%), 10 had a myocardial infarction (18%), 11 had repeat bypass surgery (20%), 8 had repeat percutaneous interventions (14%), and 30 had one or more cardiac-related hospital admissions (54%). The incidence of these events was similar in group II except for a slightly higher incidence of myocardial infarction: 6 patients died (10%), 3 had a myocardial infarction (5%), 12 had repeat bypass surgery (20%), 12 had repeat percutaneous interventions (20%), and 26 had one or more cardiac-related hospital admissions (44%). CONCLUSIONS: Unlike ostial native coronary disease, the clinical, procedural and follow-up profile of ostial saphenous vein graft revascularization is not significantly worse than proximal nonostial disease. This finding may be related to the overall suboptimal results of percutaneous revascularization in saphenous vein grafts compared with native coronary arteries or to the unfavorable intrinsic properties of ostial native coronary arteries compared with ostial vein grafts.


Assuntos
Angioplastia Coronária com Balão , Aterectomia Coronária , Ponte de Artéria Coronária , Oclusão de Enxerto Vascular/terapia , Veia Safena/transplante , Estudos de Casos e Controles , Feminino , Seguimentos , Oclusão de Enxerto Vascular/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento
20.
J Am Coll Cardiol ; 5(6): 1377-81, 1985 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3889098

RESUMO

Thirty-one consecutive patients undergoing intravenous blurred mask digital subtraction right ventriculography were submitted to first pass radionuclide angiography. Second order mask resubtraction of end-diastolic and end-systolic right ventricular digital image frames was executed using preinjection end-diastolic and end-systolic frames to rid the digital subtraction images of mis-registration artifact. End-diastolic and end-systolic perimeters were drawn manually by two independent observers with a light pen. Ejection fractions calculated from the integrated videodensitometric counts within these perimeters correlated well with those derived from the first pass radionuclide right ventriculogram (r = 0.84) and the interobserver correlation was acceptable (r = 0.91). Interobserver differences occurred more frequently in patients with atrial fibrillation and in those whose tricuspid valve planes were difficult to discern on the digital subtraction right ventriculograms. These results suggest that videodensitometric analysis of digital subtraction right ventriculograms is an accurate method of determining right ventricular ejection fraction and may find wide clinical applicability.


Assuntos
Absorciometria de Fóton/métodos , Débito Cardíaco , Ventrículos do Coração/diagnóstico por imagem , Volume Sistólico , Adulto , Idoso , Computadores , Feminino , Cardiopatias/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Ácido Pentético , Cintilografia , Técnica de Subtração , Tecnécio , Pentetato de Tecnécio Tc 99m , Tecnologia Radiológica , Gravação de Videoteipe
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