Spelling suggestions: "subject:"cardiac work"" "subject:"ardiac work""
1 |
Jogos de realidade virtual em indivíduos pós-acidente vascular cerebral: respostas fisiológicas agudas e sua reprodutibilidade / Virtual reality games for post-stroke subjects: acute physiological responses and their reproducibilitySousa, Julio Cesar Silva de 04 May 2017 (has links)
Os jogos de realidade virtual (JRV) são utilizados como estratégia complementar de reabilitação motora em indivíduos pós-acidente vascular cerebral (AVC). Porém, o impacto cardiovascular e metabólico desses jogos foi pouco investigado, o que é essencial para uma reabilitação completa. Com esse intuito, este estudo avaliou as respostas de frequência cardíaca (FC) e consumo de oxigênio (VO2) durante os JRV, comparando-as ao limiar anaeróbio (Lan) e ao ponto de compensação respiratória (PCR) e calculando o gasto energético (GE). Além disso, investigou-se as respostas da FC, pressão arterial (PA) e duplo produto (DP) no período pós-JRV e a reprodutibilidade de todas as respostas aos JRV. Para tanto, 12 indivíduos (84% homens, 56±12 anos) em fase crônica após um único AVC participaram, em ordem aleatória, de três sessões experimentais, sendo duas delas de JRV e uma controle. Nas sessões de JRV, os indivíduos foram submetidos a 4 blocos de jogos intercalados por 2 min de pausa; cada bloco foi composto por 3 min do jogo Tênis de Mesa, seguidos de 1 min de pausa e 4 min do jogo Boxe (Xbox360+Kinect). Na sessão controle, os indivíduos assistiram a um filme sentados por 38 min. A FC e o VO2 foram continuamente medidos durante as sessões, e a PA e FC foram medidas antes e aos 15 e 30 min após as intervenções. O GE foi calculado a partir do VO2. As respostas de FC e VO2 nos JRV tiveram boa reprodutibilidade (coeficiente de correlação intraclasse > 0,75 e baixo erro médio da medida). Os valores de FC medidos durante os JRV foram semelhantes ao Lan e significantemente inferiores ao PCR, com mais de 50% dos indivíduos apresentando FC abaixo do Lan em todos os JRV. O VO2 medido durante os JRV foi significantemente menor que o Lan e o PCR, com mais de 75% dos indivíduos com VO2 abaixo do Lan em todos os jogos. O GE médio da sessão de JRV foi de ? 4,6±0,1 kcal/min, totalizando 169±11 kcal. Após a sessão de JRV, a PA não se modificou, a FC e o DP permaneceram aumentados por 30 min. Conclui-se que, em indivíduos pós-AVC, a sessão de JRV proposta promoveu respostas fisiológicas reprodutíveis, que corresponderam a uma intensidade próxima e abaixo do Lan, gerando um GE médio de cerca de 4 kcal/min (3 METS) e mantendo o trabalho cardíaco aumentado por até 30 min após a sessão / Virtual reality games (VRG) has been used as a complementary strategy for motor rehabilitation in stroke survivors. However, the cardiovascular and metabolic impacts produced by these games has been poorly investigated, which is important for a complete rehabilitation. To investigate this impact, this study evaluated heart rate (HR) and oxygen consumption (VO2) responses during VRG, comparing these responses with anaerobic threshold (AT) and respiratory compensation point (RCP), and calculating the energy expenditure (EE). Furthermore, the responses of HR, blood pressure (BP) and rate pressure product (RPP) after the VRG session as well as the reproducibility of all the responses to VRG were evaluated. For that, 12 chronic post-stroke patients (84% men, 56±12 years) underwent, in random order, 3 experimental sessions: two composed by VRG and one control session. The VRG sessions were composed by 4 blocks of games interpolated by 2 min of rest, and each block was composed by 3 min of the table tennis game followed by 1 min of rest and 4 min of the boxing game (Xbox360+Kinect). In the control session, the subjects watched a film in the seating position for 38 min. HR and VO2 were continuously measured during the sessions, and HR and BP were also measured before and at 15 and 30 min after the interventions. EE was calculated from VO2. HR and VO2 responses to VRG showed good reproducibility (intraclass correlation index > 75% and low standard error of measurement). HR measured during the VRG was similar to AT and significantly lower than RCP, with more than 50% of the subjects presenting HR below AT in all the games. VO2 measured during the VRG was significantly lower than AT and RCP, with more than 75% of the subjects presenting VO2 below AT in all the games. VRG EE was ?4.6±0.1 kcal/min, totalizing 169±11 kcal. After the VRG session, BP did not change, while HR and RPP remained significantly increased up to 30 min. In conclusion, in post-stroke survivors, the proposed VRG session produced physiological responses that have good reproducibility and corresponded to an intensity near to and below the AT, generating a mean EE of 4 kcal/min (3 METs), and maintaining cardiac work elevated for at least 30 min after its end
|
2 |
Jogos de realidade virtual em indivíduos pós-acidente vascular cerebral: respostas fisiológicas agudas e sua reprodutibilidade / Virtual reality games for post-stroke subjects: acute physiological responses and their reproducibilityJulio Cesar Silva de Sousa 04 May 2017 (has links)
Os jogos de realidade virtual (JRV) são utilizados como estratégia complementar de reabilitação motora em indivíduos pós-acidente vascular cerebral (AVC). Porém, o impacto cardiovascular e metabólico desses jogos foi pouco investigado, o que é essencial para uma reabilitação completa. Com esse intuito, este estudo avaliou as respostas de frequência cardíaca (FC) e consumo de oxigênio (VO2) durante os JRV, comparando-as ao limiar anaeróbio (Lan) e ao ponto de compensação respiratória (PCR) e calculando o gasto energético (GE). Além disso, investigou-se as respostas da FC, pressão arterial (PA) e duplo produto (DP) no período pós-JRV e a reprodutibilidade de todas as respostas aos JRV. Para tanto, 12 indivíduos (84% homens, 56±12 anos) em fase crônica após um único AVC participaram, em ordem aleatória, de três sessões experimentais, sendo duas delas de JRV e uma controle. Nas sessões de JRV, os indivíduos foram submetidos a 4 blocos de jogos intercalados por 2 min de pausa; cada bloco foi composto por 3 min do jogo Tênis de Mesa, seguidos de 1 min de pausa e 4 min do jogo Boxe (Xbox360+Kinect). Na sessão controle, os indivíduos assistiram a um filme sentados por 38 min. A FC e o VO2 foram continuamente medidos durante as sessões, e a PA e FC foram medidas antes e aos 15 e 30 min após as intervenções. O GE foi calculado a partir do VO2. As respostas de FC e VO2 nos JRV tiveram boa reprodutibilidade (coeficiente de correlação intraclasse > 0,75 e baixo erro médio da medida). Os valores de FC medidos durante os JRV foram semelhantes ao Lan e significantemente inferiores ao PCR, com mais de 50% dos indivíduos apresentando FC abaixo do Lan em todos os JRV. O VO2 medido durante os JRV foi significantemente menor que o Lan e o PCR, com mais de 75% dos indivíduos com VO2 abaixo do Lan em todos os jogos. O GE médio da sessão de JRV foi de ? 4,6±0,1 kcal/min, totalizando 169±11 kcal. Após a sessão de JRV, a PA não se modificou, a FC e o DP permaneceram aumentados por 30 min. Conclui-se que, em indivíduos pós-AVC, a sessão de JRV proposta promoveu respostas fisiológicas reprodutíveis, que corresponderam a uma intensidade próxima e abaixo do Lan, gerando um GE médio de cerca de 4 kcal/min (3 METS) e mantendo o trabalho cardíaco aumentado por até 30 min após a sessão / Virtual reality games (VRG) has been used as a complementary strategy for motor rehabilitation in stroke survivors. However, the cardiovascular and metabolic impacts produced by these games has been poorly investigated, which is important for a complete rehabilitation. To investigate this impact, this study evaluated heart rate (HR) and oxygen consumption (VO2) responses during VRG, comparing these responses with anaerobic threshold (AT) and respiratory compensation point (RCP), and calculating the energy expenditure (EE). Furthermore, the responses of HR, blood pressure (BP) and rate pressure product (RPP) after the VRG session as well as the reproducibility of all the responses to VRG were evaluated. For that, 12 chronic post-stroke patients (84% men, 56±12 years) underwent, in random order, 3 experimental sessions: two composed by VRG and one control session. The VRG sessions were composed by 4 blocks of games interpolated by 2 min of rest, and each block was composed by 3 min of the table tennis game followed by 1 min of rest and 4 min of the boxing game (Xbox360+Kinect). In the control session, the subjects watched a film in the seating position for 38 min. HR and VO2 were continuously measured during the sessions, and HR and BP were also measured before and at 15 and 30 min after the interventions. EE was calculated from VO2. HR and VO2 responses to VRG showed good reproducibility (intraclass correlation index > 75% and low standard error of measurement). HR measured during the VRG was similar to AT and significantly lower than RCP, with more than 50% of the subjects presenting HR below AT in all the games. VO2 measured during the VRG was significantly lower than AT and RCP, with more than 75% of the subjects presenting VO2 below AT in all the games. VRG EE was ?4.6±0.1 kcal/min, totalizing 169±11 kcal. After the VRG session, BP did not change, while HR and RPP remained significantly increased up to 30 min. In conclusion, in post-stroke survivors, the proposed VRG session produced physiological responses that have good reproducibility and corresponded to an intensity near to and below the AT, generating a mean EE of 4 kcal/min (3 METs), and maintaining cardiac work elevated for at least 30 min after its end
|
3 |
Effects of Leonotis leonurus aqueous extract on the isolated perfused rat heartKhan, Fatima January 2007 (has links)
Doctor Pharmaceuticae - DPharm / An aqueous extract prepared from the leaves and smaller stems of Leonotis leonurus
was used to investigate the potential effects on certain cardiovascular parameters,
such as left ventricular systolic pressure, end-diastolic pressure, developed pressure,
heart rate, cardiac work and coronary perfusion pressure in isolated rat hearts. Hearts
were perfused at constant flow for 3min using the modified Langendorf! perfused
model of the heart. Effects of adrenaline and digoxin solutions on the isolated heart
were compared to that of the plant extract. Adrenaline produced both positive
inotropic and chronotropic effects. Adrenaline increased (p<O.Ol) the left ventricular
systolic pressure and hence the left ventricular developed pressure by 40.6% and
43.9% at peak, and 24.3% and 31.9%, after 3min, respectively. Simultaneously, the
heart rate and the cardiac work were increased (p<0.01) by 22.5% and 89.4% at peak,
and 24.6% and 63%, after 3rnin, respectively. There were no significant effects on the
left ventricular diastolic pressure and the coronary perfusion pressure. Digoxin
solution (2.5ng/ml) significantly (p<O.Ol) increased the left ventricular systolic
pressure by 5.1% after 3min and the left ventricular diastolic pressure by 9.7% at peak
and 5.3% after 3min. The heart rate was significantly (p<O.OI) decreased by 3.7% at
peak. The cardiac work was increased by 4.5% after 3rnin. Digoxin did not
significantly affect the left end diastolic pressure and the coronary perfusion pressure.
The extract of Leonons leonurus at O.lmg/ml increased (p<O.OI) the left ventricular
systolic pressure and hence the left ventricular diastolic pressure by 9.7% and 10.7%
at peak, and 5.4% and 5.5% after 3rnin, respectively. The cardiac work was increased
(p<O.Ol) by 10.1% at peak. Leonotis leonurus (0.1mg/ml) did not significantly affect
the left ventricular end diastolic pressure, the heart rate and the coronary perfusion
pressure. At 0.5mg/ml, the left ventricular systolic pressure and hence the left
ventricular diastolic pressure were increased (p<0.01) by 14.8% and 15.4% at peak
and 7.4% and 7.8% after 3rnin, respectively with a corresponding decrease (p<O.OI)
in the coronary perfusion pressure of 8.5% at peak and 4.4% after 3rnin. The cardiac
work was increased (p<O.OI) by 13.6% at peak and 5.2% after 3rnin. The extract at
1.0mg/ml increased (p<O.Ol) the left ventricular systolic pressure and hence the left
ventricular diastolic pressure by 25.4% and 29.4% at Peak, and 23.1% and 26.3%
after 3rnin, respectively. The heart rate was reduced (p<O.OI) by 34.7% at peak and
28.3% after 3min. The cardiac work and the coronary perfusion pressure were
decreased (p<O.OI) by 15.9% and 12.1% at Peak and 3.3% and 11.4% after 3rnin.
However, at 2.0mg/ml, the left ventricular systolic pressure and the left ventricular
diastolic pressure were increased (p<O.OI) by 14.9% at peak. The left ventricular
diastolic pressure was decreased (p<O.OI)by 9.8% over the 3rnin. The heart rate was
drastically decreased (p<O.OI) by 42.7% after 3rnin. The cardiac work was reduced
(p<O.Ol) by 48.8% over the 3min period. Also, the coronary perfusion pressure was
decreased (p<0.01) by 16.9% at peak.
Thus, Leonatis leonurus produced both positive inotropic and negative chronotropic
effects after 3min perfusion, accompanied by a decreased coronary perfusion
pressure. Thus, it appears that the extract seemed to contain certain constituents
associated with positive inotropic and negative chronotropic agents as wel! as
constituents associated with coronary vasodilation. However, at the higher
concentration, it seemed to contain some constituents associated with toxic effects on
the isolated heart.
Therefore, further studies are needed to isolate the various constituents and examine
their possible pharmacological effects on the heart individually before it could be
considered safe to recommend this plant for its use in the treatment of cardiovascular
disease.
|
Page generated in 0.0309 seconds