Sudden cardiac death athletes: a systematic review.

Previous events evidence that sudden cardiac death (SCD) in athletes is still a reality and it keeps challenging cardiologists. Considering the importance of SCD in athletes and the requisite for an update of this matter, we endeavored to describe SCD in athletes. The Medline (via PubMed) and SciELO databases were searched using the subject keywords "sudden death, athletes and mortality". The incidence of SCD is expected at one case for each 200,000 young athletes per year. Overall it is resulted of complex dealings of factors such as arrhythmogenic substrate, regulator and triggers factors. In great part of deaths caused by heart disease in athletes younger than 35 years old investigations evidence cardiac congenital abnormalities. Athletes above 35 years old possibly die due to impairments of coronary heart disease, frequently caused by atherosclerosis. Myocardial ischemia and myocardial infarction are responsible for the most cases of SCD above this age (80%). Pre-participatory athletes' evaluation helps to recognize situations that may put the athlete's life in risk including cardiovascular diseases. In summary, cardiologic examinations of athletes' pre-competition routine is an important way to minimize the risk of SCD.

Strain differences in baroceptor reflex in adult Wistar Kyoto rats.

OBJECTIVES: A subset of normotensive Sprague-Dawley rats show lower baroreflex sensitivity; however, no previous study investigated whether there are differences in baroreflex sensitivity within this subset. Our study compared baroreflex sensitivity among conscious rats of this specific subtype. METHODS: Male Wistar Kyoto (WKY) rats (16 weeks old) were studied. Cannulas were inserted into the abdominal aortic artery through the right femoral artery to measure mean arterial pressure (MAP) and heart rate (HR). Baroreflex gain was calculated as the ratio between change in HR and MAP variation (DeltaHR/DeltaMAP) in response to a depressor dose of sodium nitroprusside (SNP, 50 microg/kg, i.v.) and a pressor dose of phenylephrine (PE, 8 microg/kg, i.v.). Rats were divided into four groups: 1) low bradycardic baroreflex (LB), baroreflex gain (BG) between -1 and -2 bpm/mmHg tested with PE; 2) high bradycardic baroreflex (HB), BG < -2 bpm/mmHg tested with PE; 3) low tachycardic baroreflex (LT), BG between -1 and -2 bpm/mmHg tested with SNP and; 4) high tachycardic baroreflex (HT), BG < -2 bpm/mmHg tested with SNP. Significant differences were considered for p < 0.05. RESULTS: Approximately 37% of the rats showed a reduced bradycardic peak, bradycardic reflex and decreased bradycardic gain of baroreflex while roughly 23% had a decreased basal HR, tachycardic peak, tachycardic reflex and reduced sympathetic baroreflex gain. No significant alterations were noted with regard to basal MAP. CONCLUSION: There is variability regarding baroreflex sensitivity among WKY rats from the same laboratory.

Strain differences in baroceptor reflex in adult Wistar Kyoto rats

OBJECTIVES: A subset of normotensive Sprague-Dawley rats show lower baroreflex sensitivity; however, no previous study investigated whether there are differences in baroreflex sensitivity within this subset. Our study compared baroreflex sensitivity among conscious rats of this specific subtype. METHODS: Male Wistar Kyoto (WKY) rats (16 weeks old) were studied. Cannulas were inserted into the abdominal aortic artery through the right femoral artery to measure mean arterial pressure (MAP) and heart rate (HR). Baroreflex gain was calculated as the ratio between change in HR and MAP variation (ÄHR/ÄMAP) in response to a depressor dose of sodium nitroprusside (SNP, 50 µg/kg, i.v.) and a pressor dose of phenylephrine (PE, 8 µg/kg, i.v.). Rats were divided into four groups: 1) low bradycardic baroreflex (LB), baroreflex gain (BG) between -1 and -2 bpm/mmHg tested with PE; 2) high bradycardic baroreflex (HB), BG < -2 bpm/mmHg tested with PE; 3) low tachycardic baroreflex (LT), BG between -1 and -2 bpm/mmHg tested with SNP and; 4) high tachycardic baroreflex (HT), BG < -2 bpm/mmHg tested with SNP. Significant differences were considered for p < 0.05. RESULTS: Approximately 37 percent of the rats showed a reduced bradycardic peak, bradycardic reflex and decreased bradycardic gain of baroreflex while roughly 23 percent had a decreased basal HR, tachycardic peak, tachycardic reflex and reduced sympathetic baroreflex gain. No significant alterations were noted with regard to basal MAP. CONCLUSION: There is variability regarding baroreflex sensitivity among WKY rats from the same laboratory.

Intra-strain variations of baroreflex sensitivity in young Wistar-Kyoto rats.

PURPOSE: To compare baroreflex sensitivity among conscious rats of the same strain. METHODS: Male WKY rats (eight weeks old) were studied. Cannulas were inserted into the abdominal aortic artery through the right femoral artery to measure mean arterial pressure (MAP) and heart rate (HR). Baroreflex gain was calculated as the ratio between variation of HR in function of the MAP variation (?HR/?MAP) tested with a depressor dose of sodium nitroprusside (SNP, 50 microg/kg, iv) and with a pressor dose of phenylephrine (PE, 8 microg/kg, iv). We divided the rats into four groups: 1) Low bradycardic baroreflex (LB), BG between -1 and -2 bpm/mmHg tested with PE; 2) High bradycardic baroreflex (HB), BG < -2 bpm/mmHg tested with PE; 3) Low tachycardic baroreflex (LT), BG between -1 and -2 bpm/mmHg tested with SNP and; 4) High tachycardic baroreflex (HT), BG < -2 bpm/mmHg tested with SNP. Significant differences were considered for p < 0.05. RESULTS: Approximately 82% of the rats presented reduced bradycardic reflex while 22 showed attenuated tachycardic reflex. No alterations were noted regarding basal MAP and HR, tachycardic and bradycardic peak and HR range. CONCLUSIONS: There was alteration in baroreflex sensitivity among rats of the same strain. Care should be taken when interpreting studies employing WKY as a control for the SHR.

A hipotermia como estratégia protetora de encefalopatia hipóxico-isquêmica em recém-nascidos com asfixia perinatal / Hypothermy as a protective strategy in asphyxiated newborns after hypoxic-ischemic encephalopathy

INTRODUÇÃO: a encefalopatia hipóxico isquêmica neonatal é uma doença devastadora para o cérebro do recém-nascido. Nas últimas duas décadas, as pesquisas experimentais trouxeram grande avanço nos conhecimentos fisiopatológicos. Para a integridade neuronal, é necessária energia suficiente para a célula manter o equilíbrio iônico. A hipotermia tem sido estudada como um método com alto grau de neuroproteção na hipóxia-isquemia (HI). OBJETIVO: verificar a potencialidade terapêutica da hipotermia como tratamento da encefalopatia hipóxico-isquêmica em recém-nascidos. MÉTODO: foram consultadas as bases de dados do Medline, Lilacs, Scielo e JCR-ISI. As consultas incluíram artigos registrados entre 1993 e 2008 no idioma Português, Inglês e Espanhol. DISCUSSÃO: encefalopatia hipóxico- isquêmica neonatal é complicação imediata à asfixia grave e pode causar graus variados de dano cerebral. As características do dano hipóxico isquêmico indicam que existe um período intermediário, em que é possível intervir interrompendo a cadeia de eventos que levam a destruição celular definitiva. Com a finalidade de proteger o cérebro dos insultos isquêmicos, utilizam-se drogas e diferentes procedimentos, tais como manitol, removedores de radicais livres, antagonistas de receptores opiáceos, supressores de metabolismo e hipotermia para minimizar as lesões. CONCLUSÃO: o resfriamento cerebral é a conduta terapêutica promissora em reduzir danos cerebrais em recém-nascidos.(AU)

INTRODUCTION: The nutritional needs and particularly, the energetic metabolism in childhood is a controversy in the literature. OBJECTIVE: To characterize the energetic spent at rest in children with sepsis. METHOD: The database of Medline and SciELO was consulted. We used as search strategy the words: newborn and energy spent or sepsis in all fields. RESULTS: In the case of sepsis , the child presents immaturity of the enzymatic system, which limits the production of some aminoacids, such as cystein (cistationase enzyme deficit in preterm), taurine, gutamine and nucleotides as coline e inositol. This fact turns those nutrients conditionally essential for children. CONCLUSION: Many concepts for adults are used in childohood, which is not correct and may cause several consequences to the health of children.(AU)

A hipotermia como estratégia protetora de encefalopatia hipóxico-isquêmica em recém-nascidos com asfixia perinatal / Hypothermy as a protective strategy in asphyxiated newborns after hypoxic-ischemic encephalopathy

INTRODUÇÃO: a encefalopatia hipóxico isquêmica neonatal é uma doença devastadora para o cérebro do recém-nascido. Nas últimas duas décadas, as pesquisas experimentais trouxeram grande avanço nos conhecimentos fisiopatológicos. Para a integridade neuronal, é necessária energia suficiente para a célula manter o equilíbrio iônico. A hipotermia tem sido estudada como um método com alto grau de neuroproteção na hipóxia-isquemia (HI). OBJETIVO: verificar a potencialidade terapêutica da hipotermia como tratamento da encefalopatia hipóxico-isquêmica em recém-nascidos. MÉTODO: foram consultadas as bases de dados do Medline, Lilacs, Scielo e JCR-ISI. As consultas incluíram artigos registrados entre 1993 e 2008 no idioma Português, Inglês e Espanhol. DISCUSSÃO: encefalopatia hipóxico- isquêmica neonatal é complicação imediata à asfixia grave e pode causar graus variados de dano cerebral. As características do dano hipóxico isquêmico indicam que existe um período intermediário, em que é possível intervir interrompendo a cadeia de eventos que levam a destruição celular definitiva. Com a finalidade de proteger o cérebro dos insultos isquêmicos, utilizam-se drogas e diferentes procedimentos, tais como manitol, removedores de radicais livres, antagonistas de receptores opiáceos, supressores de metabolismo e hipotermia para minimizar as lesões. CONCLUSÃO: o resfriamento cerebral é a conduta terapêutica promissora em reduzir danos cerebrais em recém-nascidos.

INTRODUCTION: The nutritional needs and particularly, the energetic metabolism in childhood is a controversy in the literature. OBJECTIVE: To characterize the energetic spent at rest in children with sepsis. METHOD: The database of Medline and SciELO was consulted. We used as search strategy the words: newborn and energy spent or sepsis in all fields. RESULTS: In the case of sepsis , the child presents immaturity of the enzymatic system, which limits the production of some aminoacids, such as cystein (cistationase enzyme deficit in preterm), taurine, gutamine and nucleotides as coline e inositol. This fact turns those nutrients conditionally essential for children. CONCLUSION: Many concepts for adults are used in childohood, which is not correct and may cause several consequences to the health of children.