RESUMO
OBJECTIVE: To study vascular reactivity according to the analysis of blood flow and peripheral vascular resistance at rest and during mental stress in pregnant women with mitral stenosis. METHODS: Twenty two women with mitral stenosis, 13 of whom were pregnant (PS) and 9 were non-pregnant (MIS), and 9 healthy pregnant women (NP) were studied. During gestation, 9 out of the 13 patients of the PS group required a beta-blocker (PSB) and the remaining 4 progressed without medication (PSWB). Plethysmography at rest and during mental stress analyzed muscle blood flow, peripheral vascular resistance (PVR), mean arterial pressure (MAP) and heart rate (HR) during gestation and puerperium. RESULTS: During gestation of PSWB, muscle blood flow and HR were higher in 1.6% and 20.5% (p = 0.05), and PVR and MAP were lower in 19.3% and 4.4%, respectively, in comparison to the puerperium; during mental stress, the muscle blood flow increased by 55.9%, HR decreased by 30.2% and PVR and MAP were similar. In PSB, muscle blood muscle blood flow and HR were greater in 5.9% and 14.9% (p= 0.001) and MAP and PVR were lower in 10.3% and 9.1%, respectively, when compared to the puerperium. During mental stress, muscle blood flow and MAP increased by 69.8% and 174.1%, respectively. HR was similar and PVR decreased by 53.7%. The comparative study showed that in the NP group the muscle blood flow was higher, PVR was lower, and MAP and HR were similar in relation to the PS group, and that the PS, NP, MIS groups had a similar response to mental stress. CONCLUSIONS: Vascular reactivity in pregnant women with mitral stenosis was preserved and the analysis of measurements showed lower values of muscle blood flow and higher values of PVR when compared to those of healthy pregnant women.
Assuntos
Vasos Sanguíneos/fisiopatologia , Estenose da Valva Mitral/fisiopatologia , Músculos/irrigação sanguínea , Complicações Cardiovasculares na Gravidez/fisiopatologia , Estresse Psicológico/fisiopatologia , Adolescente , Adulto , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Vasos Sanguíneos/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Estenose da Valva Mitral/metabolismo , Gravidez , Complicações Cardiovasculares na Gravidez/metabolismo , Estudos Prospectivos , Fluxo Sanguíneo Regional , Estresse Psicológico/metabolismo , Resistência VascularRESUMO
OBJETIVO: Estudar a reatividade vascular mediante a análise do fluxo sangüíneo e da resistência vascular periférica em repouso e estresse mental na gravidez de mulheres com estenose mitral. MÉTODOS: Foram estudadas 22 mulheres portadoras de estenose mitral, 13 grávidas (GE) e 9 não-grávidas (EM), e 9 gestantes saudáveis voluntárias (GN). Na gestação, 9 (GEB) das 13 do GE necessitaram de betabloqueador e 4 restantes (GESB) evoluíram sem medicação. A plestimografia em repouso e sob estresse mental analisou o fluxo sangüíneo muscular, resistência vascular periférica (RVP), pressão arterial média (PAM) e freqüência cardíaca (FC) na gestação e no puerpério. RESULTADOS: Na gestação do GESB, os valores do fluxo sangüíneo muscular e da FC foram maiores em 1,6 por cento e 20,5 por cento (p = 0,05), e os da RVP e da PAM foram menores em 19,3 por cento e 4,4 por cento, respectivamente, em comparação ao puerpério; no estresse mental, o fluxo sangüíneo muscular aumentou em 55,9 por cento, a FC reduziu em 30,2 por cento e houve semelhança da RVP e PAM. No GEB, os valores do fluxo e da FC foram maiores em 5,9 por cento e 14,9 por cento (p = 0,001) e os da PAM e da RVP menores em 10,3 por cento e 9,1 por cento, respectivamente, quando comparados ao puerpério; no estresse mental o fluxo e a PAM aumentaram em 69,8 por cento e 174,1 por cento, respectivamente, a FC foi semelhante e a RVP reduziu em 53,7 por cento. O estudo comparativo mostrou que no grupo GN o fluxo sangüíneo muscular foi maior, a RVP menor e houve semelhança na PAM e FC em relação ao grupo GE e que os grupos GE, GN, EM apresentaram semelhança na resposta ao estresse mental. CONCLUSÕES: A reatividade vascular na gestação de mulheres com estenose mitral foi preservada e a análise das medidas mostrou valores menores de fluxo sangüíneo muscular e maiores da RVP quando comparados às gestantes saudáveis.
Assuntos
Adolescente , Adulto , Feminino , Humanos , Gravidez , Vasos Sanguíneos/fisiopatologia , Estenose da Valva Mitral/fisiopatologia , Músculos/irrigação sanguínea , Complicações Cardiovasculares na Gravidez/fisiopatologia , Estresse Psicológico/fisiopatologia , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Vasos Sanguíneos/metabolismo , Estudos de Casos e Controles , Estenose da Valva Mitral/metabolismo , Estudos Prospectivos , Complicações Cardiovasculares na Gravidez/metabolismo , Fluxo Sanguíneo Regional , Estresse Psicológico/metabolismo , Resistência VascularRESUMO
The distribution of prostaglandin-E2 (PGE2) and prostaglandin-F2 alpha (PGF2 alpha) was studied in subcellular fractions isolated from homogenates of human atrial fresh tissue by differential centrifugation. Right and left atrial samples were excised from the same heart of six patients with mitral valve disease at the time of open heart surgery. The atrial fractions investigated were mitochondrial (8,500 g pellet), microsomal (100,000 g pellet) and cytosol soluble (100,000 g supernatant) fractions. After extraction of prostaglandins from the three atrial fractions and separation of PGE from PGF series by chromatography on silicic acid column, these prostaglandins were measured by radioimmunoassay. The results showed that PGE2 and PGF2 alpha were located mainly in the soluble cytosolic fraction of right and left atrial tissue (p < 0.001). Furthermore, the prostaglandins levels were higher in left than in right atria of these patients (p < 0.001). The relation between prostaglandins heart generation in response to elevated work load of mitral valve disease is discussed.
Assuntos
Dinoprosta/metabolismo , Dinoprostona/metabolismo , Insuficiência da Valva Mitral/metabolismo , Estenose da Valva Mitral/metabolismo , Ocitócicos/metabolismo , Adulto , Dinoprosta/análise , Dinoprostona/análise , Feminino , Átrios do Coração/química , Átrios do Coração/metabolismo , Humanos , Masculino , Valva Mitral/química , Ocitócicos/análise , Frações SubcelularesRESUMO
The distribution of prostaglandin-E2 (PGE2) and prostaglandin-F2alpha (PGF2alpha) was studied in subcellular fractions isolated from homogenates of human atrial fresh tissue by differential centrifugation. Right and left atrial samples were excised from the same heart of six patients with mitral valve disease at the time of open heart surgery. The atrial fractions investigated were mitochondrial (8,500 g pellet), microsomal (100,000 g pellet) and cytosol soluble (100,000 g supernatant) fractions. After extraction of prostaglandins from the three atrial fractions and separation of PGE from PGF series by chromatography on silicic acid column, these prostaglandins were measured by radioimmunoassay. The results, showed that PGE2 and PGF2alpha were located mainly in the soluble cytosolic fraction of right and left atrial tissue (p<0.001). Furthermore, the prostaglandins levels were higher in left than in right atria of these patients (p<0.001). The relation between prostaglandins heart generation in response to elevated work load of mitral valve disease is discussed.