RESUMO
Near-infrared spectroscopy combined with vascular occlusion test (NIRS-VOT) is a reactive hyperemia technique for in vivo evaluation of skeletal muscle microvascular reactivity. Previous studies using NIRS-VOT have been shown to be able to detect impairments in microvascular function in high-risk cardiovascular disease populations, such as older individuals. It has been demonstrated that older individuals have slower reactive hyperemia compared with young individuals. Importantly, older individuals also show less desaturation during ischemia compared with young individuals. Based on these findings, it has been suggested that the slower reactive hyperemia observed in older individuals is explained by the lower desaturation during blood flow occlusion (reduced ischemic stimulus). This retrospective analysis compared reactive hyperemia in 36 young and 47 older tissue desaturation-matched individuals that underwent 5-min blood flow occlusion. Overall, we showed that older individuals have impaired reactive hyperemia compared with young when matching for the degree of desaturation and blood flow occlusion time. These findings provide evidence that lower tissue desaturation during ischemia is not a major determinant of impaired reactive hyperemia in older individuals.NEW & NOTEWORTHY Previous findings have suggested that aging-related impairment in skeletal muscle reactive hyperemia is majorly influenced by a lower degree of tissue desaturation during ischemia in older individuals compared with young individuals. In a retrospective analysis including 83 tissue desaturation-matched individuals, we show that the degree of tissue desaturation is not a major determinant of aging-related impairments in reactive hyperemia.
Assuntos
Envelhecimento , Hiperemia , Microcirculação , Músculo Esquelético , Fluxo Sanguíneo Regional , Espectroscopia de Luz Próxima ao Infravermelho , Hiperemia/fisiopatologia , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatologia , Humanos , Estudos Retrospectivos , Masculino , Envelhecimento/metabolismo , Envelhecimento/fisiologia , Idoso , Feminino , Adulto , Adulto Jovem , Pessoa de Meia-Idade , Fatores Etários , Isquemia/fisiopatologia , Isquemia/metabolismo , Oxigênio/sangue , Oxigênio/metabolismoRESUMO
Social determinants of health (SDOHs) are broadly defined as nonmedical factors that impact the outcomes of one's health. SDOHs have been increasingly recognized in the literature as profound and modifiable factors on the outcomes of vascular care in peripheral artery disease (PAD) and chronic limb-threatening ischemia (CLTI) despite surgical and technological advancements. In this paper, we briefly review the SDOH and its impact on the management and outcome of patients with CLTI. We highlight the importance of understanding how SDOH impacts our patient population so the vascular community may provide more effective, inclusive, and equitable care.
Assuntos
Isquemia Crônica Crítica de Membro , Disparidades em Assistência à Saúde , Doença Arterial Periférica , Determinantes Sociais da Saúde , Humanos , Fatores de Risco , Isquemia Crônica Crítica de Membro/cirurgia , Resultado do Tratamento , Doença Arterial Periférica/terapia , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/cirurgia , Disparidades nos Níveis de Saúde , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Medição de Risco , Isquemia/terapia , Isquemia/cirurgia , Isquemia/diagnóstico , Isquemia/diagnóstico por imagem , Isquemia/fisiopatologia , Doença CrônicaRESUMO
AIMS: The purpose of this study was to investigate the effect of PPRP (pure PRP) and LPRP (PRP with leukocytes) on recovery from limb ischemia and on expression of growth factors involved in angiogenesis, myogenesis and fibrogenesis. MATERIAL AND METHODS: PPRP and LPRP prepared by centrifugation were added to cultures of C2C12 and NIH3T3 cells (1 or 10% PRPs) to evaluate alterations in cell metabolism and expression of growth factors by MTT, ELISA and RT-qPCR, respectively. To evaluate in vivo regenerative effects, PRPs were injected into the ischemic limbs of BALB/c mice and muscle mass/strength and histomorphometry were evaluated after 30 days. KEY FINDINGS: Mice treated with PRPs after limb ischemia showed an increase in the size of myofibers and muscle strength, reduced fibrosis and adipocytes, and decreased capillary density and necrosis scores compared to untreated mice. In cell culture, serum deprivation reduced the viability of C2C12 and NIH3T3 cells to about 50%, but the addition of 1% PRPs completely recovered this loss. Both PRPs, downregulated most of the tested genes; however, angiogenic gene Vegfa in C2C12 and the fibrogenic genes Col1a1 and Col3a1 in NIH3T3 cells were upregulated by LPRP. SIGNIFICANCE: PPRP and LPRP had similar effects in regulation of genes involved in angiogenesis, myogenesis and fibrogenesis. However, the presence of leucocytes did not significantly affect regenerative activities of PRP in the ischemic limb.
Assuntos
Membro Posterior/fisiopatologia , Isquemia/fisiopatologia , Plasma Rico em Plaquetas/metabolismo , Regeneração/fisiologia , Animais , Sobrevivência Celular , Regulação da Expressão Gênica , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/patologia , Células NIH 3T3RESUMO
Infection by COVID-19, being a respiratory disease caused by SARS-CoV-2, can predispose to arterial and venous thrombotic disease, in response to excessive inflammation, platelet activation, endothelial dysfunction, and venous stasis. During the COVID-19 pandemic period, the technological and resource availability for the care of these patients with thrombotic disease is critical, marking a factor of morbidity and poor prognosis in these cases. We describe a case of priapism in a patient with COVID-19, during the course of systemic inflammatory response syndrome and respiratory distress syndrome with a procoagulant state, seeking to relate the pathophysiological factors of ischemic priapism in patients with infection with SARS-Cov-2.
Assuntos
COVID-19/complicações , Isquemia/etiologia , Ereção Peniana , Pênis/irrigação sanguínea , Priapismo/etiologia , Adulto , COVID-19/diagnóstico , COVID-19/virologia , Evolução Fatal , Humanos , Isquemia/diagnóstico , Isquemia/fisiopatologia , Masculino , Priapismo/diagnóstico , Priapismo/fisiopatologia , Fluxo Sanguíneo RegionalRESUMO
The present study analyzed the effects of local ischemia during endurance exercise on neuromuscular fatigue (NMF). Nine cyclists performed, in a counterbalanced order, two separate 4-km cycling time trials (TT) with (ISCH) or without (CONTR) induced local ischemia. NMF was characterized by using isometric maximal voluntary contractions (IMVC), whereas central [voluntary activation (VA)] and peripheral fatigue [peak torque of potentiated twitch (TwPt)] of knee extensors were evaluated using electrically evoked contractions performed before (PRE) and 1 min after (POST) the TT. Electromyographic activity (EMG), power output (PO), oxygen uptake (VÌo2), and rating of perceived exertion (RPE) were also recorded. The decrease in IMVC (-15 ± 9% vs. -10 ± 8%, P = 0.66), VA (-4 ± 3% vs. -3 ± 3%, P = 0.46), and TwPt (-16 ± 7% vs. -19 ± 14%, P = 0.67) was similar in ISCH and CONTR. Endurance performance was drastically reduced in ISCH condition (512 ± 29 s) compared with CONTR (386 ± 17 s) (P < 0.001), which was accompanied by lower EMG, PO, and VÌo2 responses (all P < 0.05). RPE was greater in ISCH compared with CONTR (P < 0.05), but the rate of change was similar throughout the TT (8.19 ± 2.59 vs. 7.81 ± 2.01 RPE.% of total time-1, P > 0.05). These results indicate that similar end-exercise NMF levels were accompanied by impaired endurance performance in ISCH compared with CONTR. These novel findings suggest that the local reduced oxygen availability affected the afferent feedback signals to the central nervous system, ultimately increasing perceived effort and reducing muscle activity and exercise intensity to avoid surpassing a sensory tolerance limit before the finish line.
Assuntos
Desempenho Atlético/fisiologia , Isquemia/fisiopatologia , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiopatologia , Adulto , Ciclismo/fisiologia , Exercício Físico/fisiologia , Humanos , Contração Isométrica/fisiologia , Articulação do Joelho/fisiologia , Articulação do Joelho/fisiopatologia , Masculino , Músculo Esquelético/fisiologiaRESUMO
Abstract Aim: In the process of aging, there is a decrease on muscle strength and cognitive function. Resistance training combined with blood flow restriction (BFRRT) has been shown capable of maintaining or improve aspects of physical health. However, the effects of BFRRT the cognitive function of the elderly are not clear. This study aimed to describe the design of a randomized controlled clinical trial, that will investigate the effects of BFRRT on cognitive function, physical performance and physiological and morphological aspects in elderly women. Methods: Forty participants will be randomized into one of the following groups: low load resistance training, blood flow restriction resistance training, moderate load resistance training or Control. All intervention groups will complete 16 weeks of resistance training, three times week (45 minutes each), with training consisting of four exercises for the upper and lower body, including three sets of ten repetitions each. No exercise will be performed by the Control group. Cognitive function will be the primary outcome of the study. Secondary outcomes will include body composition, muscle strength, functional capacity, double-task, level of physical activity, static and dynamic balance, brain activity, BDNF neurotrophic factor, anxiety, depression and sleep state). Conclusion: This project will contribute to the existing knowledge and will have a social impact regarding the use of physical exercise as a non-pharmacological tool for the mental and physical health older individuals. Trial Registration: Brazilian Registry of Clinical Trials number RBR-7BC8ZP.
Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Cognição , Treinamento Resistido , Isquemia/fisiopatologiaRESUMO
INTRODUCCIÓN: Los ratones SR-B1 KO/ApoER6 1h/h que son alimentados con una dieta rica en grasas saturadas, desarrollan enfermedad coronaria aterosclerótica severa, complicaciones isquémicas e insuficiencia cardíaca, con alta mortalidad. Los estudios con este modelo se han enfocado fundamentalmente en la enfermedad coronaria y menos en el remodelado cardíaco. El OBJETIVO del trabajo ha sido caracterizar el remodelado miocárdico, evaluar la evolución temporal de la función ventricular izquierda y la sobrevida asociada a enfermedad cardíaca por ateromatosis. MÉTODO: Ratones homocigotos SR-B1 KO/ApoER6 1h/h fueron alimentados por 8 semanas con dieta aterogénica o dieta normal y se comparó la sobrevida en ambos grupos. A las 4 semanas se realizó un ecocardiograma bidimensional. En los ratones eutanasiados se evaluó en la pared cardíaca fibrosis miocárdica y tamaño de los cardiomiocitos por morfometría, apoptosis con técnica de TUNEL e infiltración por células inflamatorias mononucleares (ED1) por inmunohistoquímica. RESULTADOS: En el grupo que recibió dieta aterogénica la sobrevida se redujo en 46,7% (p < 0.001), debido a muerte súbita y a falla cardíaca progresiva. En este grupo, a las 4 semanas se observó dilatación de cavidades izquierdas y disminución de la fracción de eyección del ventrículo izquierdo en comparación con el grupo control (79,3 ± 1,3% vs 66 ± 3,7%, p<0,01). También se observó aumento de la masa cardíaca relativa de 2.1 veces (p<0,001) y del peso pulmonar relativo en 80% (p<0,001), sin cambios en las dimensiones de los cardiomiocitos. En el miocardio de los ratones que recibieron dieta aterogénica hubo un aumento de la fibrosis cardíaca de 7.9 veces (p < 0.01) y del número de cardiomiocitos apoptóticos en 55.9 veces (p < 0.01), junto a un aumento del número de células inflamatorias mononucleares ED1. CONCLUSIONES: En el modelo de falla cardíaca severa de etiología isquémica con alta mortalidad en el ratón homocigoto SR-B1 KO/ApoER6 1h/h sometido a una dieta aterogénica, con falla cardíaca izquierda por disfunción sistólica, el remodelado patológico del miocardio está dado fundamentalmente por apoptosis y fibrosis. También se observa un aumento discreto de macrófagos en la pared cardíaca. Es posible que el edema parietal también pueda ser un mecanismo de remodelado relevante en este modelo.
Abstract: SR-B1 KO/ApoER6 1h/h mice fed a high saturated fat diet develop severe coronary atheromatosis, and cardiac failure with a high mortality rate. Cardiac remodeling under these conditions has not been well studied. AIM: To evaluate the time course of left ventricular function, cardiac remodeling and survival associated to the administration of an atherogenic diet. METHOD: Homozygote SR-B1 KO/ApoER6 1h/h mice received an atherogenic diet for 8 weeks. Mice receiving a normal diet served as controls. Survival rate, myocardial fibrosis, cardiomyocyte size, apoptosis and infiltration by inflammatory or mononuclear cells were compared between groups. A TUNEL technique was used to evaluate apoptosis. RESULTS: A 46.7% survival reduction compared to controls was observed in the experimental group (p<0.01), due to left ventricular and atrial dilatation associated to a decrease in ejection fraction (79,3 ± 1,3% vs 66 ± 3,7%, p<0,01, respectively). Also, an increased cardiac weight, 2.6 times greater was observed in the experimental group, compared to controls. Mice receiving the atherogenic diet showed an 80% increased lung weight. There was no evident change in cardiomyocytes, but there was more (7.9 times) cardiac fibrosis (p<0.01) and 55.9 times more apoptotic cells. (p<0.01), along with a greater number of inflammatory cells and ED1 mononuclear cells. CONCLUSION: Mice receiving an atherogenic diet develop heart failure and reduced survival rate. This is associated with cardiac remodeling with underlying apoptosis an ventricular wall fibrosis. It is posible that wall edema might contribute to the observed cardiac remodeling.
Assuntos
Animais , Camundongos , Remodelação Ventricular , Dieta Aterogênica , Insuficiência Cardíaca/etiologia , Hiperlipidemias/patologia , Isquemia/etiologia , Fibrose , Análise de Sobrevida , Função Ventricular Esquerda , Apoptose , Camundongos Knockout , Disfunção Ventricular , Modelos Animais de Doenças , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/patologia , Isquemia/fisiopatologia , Isquemia/mortalidade , Isquemia/patologiaRESUMO
The ablation of renal nerves, by destroying both the sympathetic and afferent fibers, has been shown to be effective in lowering blood pressure in resistant hypertensive patients. However, experimental studies have reported that the removal of sympathetic fibers may lead to side effects, such as the impairment of compensatory cardiorenal responses during a hemodynamic challenge. In the present study, we evaluated the effects of the selective removal of renal afferent fibers on arterial hypertension, renal sympathetic nerve activity, and renal changes in a model of renovascular hypertension. After 4 weeks of clipping the left renal artery, afferent renal denervation (ARD) was performed by exposing the left renal nerve to a 33 mM capsaicin solution for 15 min. After 2 weeks of ARD, we found reduced MAP (~ 18%) and sympathoexcitation to both the ischemic and contralateral kidneys in the hypertensive group. Moreover, a reduction in reactive oxygen species was observed in the ischemic (76%) and contralateral (27%) kidneys in the 2K1C group. In addition, ARD normalized renal function markers and proteinuria and podocin in the contralateral kidney. Taken altogether, we show that the selective removal of afferent fibers is an effective method to reduce MAP and improve renal changes without compromising the function of renal sympathetic fibers in the 2K1C model. Renal afferent nerves may be a new target in neurogenic hypertension and renal dysfunction.
Assuntos
Vias Aferentes/fisiopatologia , Hipertensão Renovascular/fisiopatologia , Isquemia/fisiopatologia , Nefropatias/fisiopatologia , Rim/fisiopatologia , Animais , Barorreflexo/fisiologia , Pressão Sanguínea/fisiologia , Masculino , Núcleo Hipotalâmico Paraventricular/fisiopatologia , Ratos , Ratos Wistar , Sistema Nervoso Simpático/fisiopatologiaRESUMO
Hepatic artery dissection is an infrequent vascular complication that can arise after orthotopic liver transplant. Most patients with this complication are diagnosed during the intraoperative period or the first days after liver transplant, with an association shown with living-donor liver transplant. In this study, we discuss a rare case of an extrahepatic artery dissection that was successfully managed through surgical excision and arterial revascularization that was diagnosed 4 years after orthotopic liver transplant. Furthermore, we hypothesize on the potential causes of its occurrence.
Assuntos
Artéria Hepática/lesões , Isquemia/etiologia , Transplante de Fígado/efeitos adversos , Lesões do Sistema Vascular/etiologia , Adulto , Anastomose Cirúrgica , Artéria Hepática/diagnóstico por imagem , Artéria Hepática/fisiopatologia , Artéria Hepática/cirurgia , Humanos , Isquemia/diagnóstico por imagem , Isquemia/fisiopatologia , Isquemia/cirurgia , Circulação Hepática , Masculino , Pessoa de Meia-Idade , Reoperação , Fatores de Tempo , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares , Lesões do Sistema Vascular/diagnóstico por imagem , Lesões do Sistema Vascular/fisiopatologia , Lesões do Sistema Vascular/cirurgiaRESUMO
BACKGROUND: To evaluate the rates of limb salvage, survival, and perioperative mortality in patients with acute limb ischemia (ALI) submitted to endovascular revascularization with pharmacomechanical thrombectomy (PMT) and catheter-directed thrombolysis (CDT). METHODS: This was a retrospective consecutive cohort study of patients with ALI who were submitted to endovascular treatment with PMT or fibrinolysis at the Division of Vascular and Endovascular Surgery, Hospital do Servidor Público Estadual (São Paulo, Brazil), between July 2015 and December 2018. The limb salvage rate and survival rate at 720 days were analyzed in both the PMT (group 1) and CDT treatment (group 2), as well as the perioperative mortality rate (PMR) at 30 days after surgery. RESULTS: One hundred twelve patients were admitted to the emergency department with ALI between July 2015 and December 2018. Seventeen patients diagnosed with Rutherford III irreversible ALI and 46 patients submitted to open surgery were excluded. Thus, 49 patients were submitted to endovascular surgery; 18 (36.7%) were classified into group 1, and 31 (63.3%) were classified into group 2. The clinical data were equal between the 2 groups, but there was a higher prevalence of thrombophilia in group 1 (3 cases; P < 0.001). The limb salvage rate and the overall survival rate at 720 days were similar between groups 1 and 2 (87.8% vs. 89.7%, P = 0.78 and 84.7% vs. 69.2%, P = 0.82, respectively). There was no statistical difference regarding secondary patency rates at 720 days between groups 1 and 2 (group 1, 81.9% and group 2, 78.8%; P = 0.66). The PMR was 16.7% (8 patients) within the first 30 days. Group 2 had a higher overall mortality rate (OMR) (6 patients, 19.3%, P = 0.03). Regarding the PMT group, there was a higher rate of complications such as myoglobinuria, hematuria, acute renal failure, and death in the subgroup of patients in whom there were performed more than 150 cycles/sec during the surgery (P < 0.001). CONCLUSIONS: In the present study, the PMT and CDT endovascular procedures had similar limb salvage, overall survival, and secondary patency rates. However, the OMR was higher in the CDT group. Another important finding was related to the number of cycles/sec performed in the PMT group, in whom patients with more than 150 cycles/sec have presented with higher rates of hematuria, myoglobinuria, acute renal failure, and death.