RESUMEN
The aim of this study was to assess cardiorespiratory coupling (CRC) in type 2 diabetes mellitus patients (T2DM) and apparently healthy individuals, in order to test the hypothesis that this method can provide additional knowledge to the information obtained through the heart rate variability (HRV). A cross-sectional study was conducted in T2DM patients(T2DMG=32) and health controls (CON=32). For CRC analysis, the electrocardiogram, arterial pressure, and thoracic respiratory movement were recorded at rest in supine position and during active standing. Beat-to-beat series of heart period and systolic arterial pressure were analyzed with the respiratory movement signal via a traditional non-causal approach, such as squared coherence function. In this sample of T2DM, no differences in HRV were observed when compared to the CON, but the T2DMG showed a reduction in resting CRC. We conclude that in CRC in T2DM, reflected by the squared coherence may already be compromised even before HRV changes.
Asunto(s)
Enfermedades del Sistema Nervioso Autónomo , Diabetes Mellitus Tipo 2 , Cardiopatías , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Estudios Transversales , Corazón , Sistema Nervioso Autónomo , Enfermedades del Sistema Nervioso Autónomo/diagnóstico , Enfermedades del Sistema Nervioso Autónomo/etiología , Frecuencia Cardíaca/fisiologíaRESUMEN
BACKGROUND: Cardiopulmonary exercise testing (CPET) is the gold standard for analyzing cardiorespiratory fitness and integrating physiological responses. However, the presence of chronic diseases may compromise cerebral hemodynamic responses during CPET. In addition, the acute response of cerebral oxygenation during incremental CPET may identify abnormal behavior and ensure greater safety for patients with cardiovascular, respiratory, and metabolic diseases. OBJECTIVE: To summarize the cerebral oxygenation acute response during CPET of patients with cardiovascular, metabolic, or respiratory diseases. METHODS: From inception to 23rd September 2022, five databases (PubMed, SCOPUS, Web of Science, Embase and CINAHAL) were searched for cross-sectional studies performing incremental CPET and measuring the cerebral oxygenation acute response in cardiovascular, metabolic, or respiratory diseases compared with healthy individuals. The Downs and Black tool assessed the risk of bias of the studies. RESULTS: We included seven studies with 428 participants (305 men and 123 women), aged 43 to 70 years. Of these, 101 had heart failure NYHA II and III; 77 idiopathic dilated cardiomyopathy; 33 valvular disease; 25 coronary heart disease; 22 pulmonary arterial hypertension; 15 had severe obstructive sleep apnea (OSA) and 166 were apparently healthy. There was no eligible article with metabolic disease. There was a lower magnitude increase in cerebral oxygenation of cardiovascular patients compared with the healthy individuals during the CPET. Furthermore, pulmonary arterial hypertension patients presented increased cerebral oxygen extraction, differently to those with severe OSA. CONCLUSION: Considering the heterogeneity of the included studies, patients with cardiovascular disease may suffer from reduced cerebral oxygen supply, and individuals with OSA presented lower brain oxygen extraction during the CPET. Future studies should aim for strategies to improve cerebral oxygenation to ensure greater safety at CPET of cardiovascular and OSA patients. An acute response pattern for metabolic and other respiratory diseases was not established.
Asunto(s)
Hipertensión Arterial Pulmonar , Apnea Obstructiva del Sueño , Masculino , Humanos , Femenino , Prueba de Esfuerzo , Estudios Transversales , Tolerancia al Ejercicio/fisiología , Hipoxia , Oxígeno , Consumo de Oxígeno/fisiologíaRESUMEN
Exposure of biological tissue to photobiomodulation therapy (PBMT) seems to increase the oxygen availability and mitochondrial electrochemical activity. With the advancement of new technologies, such as near-infrared spectroscopy (NIRS), information can be obtained about the balance between oxygen utilization and delivery by assessing local oxy- ([O2Hb]) and deoxy-myohemoglobin ([HHb]) concentrations, both measured in micromolars (µM). Consequently, NIRS can be used to study ("in vivo") PBMT effects on the oxidative system, including oxygen availability. Thus, the main objective of the present study was to use NIRS to investigate the acute effects of PBMT by light-emitting diode (LED) on the oxygen delivery and utilization in humans. Twelve healthy young participants were treated with a LED device (850 nm, 50 mW, 2 J) and placebo applied over the proximal third of the flexor carpi ulnaris muscle of the left or right forearm selected in a random order. The LED was applied in direct contact with skin and the device was switched on for 40 s in 4 different interventions (I1, I2, I3 and I4) with a 3-min interval between interventions. The placebo condition was considered as the period before the first PBMT. The NIRS device was used to evaluate the relative changes in [O2Hb] and [HHb] before and after placebo and interventions. We found that PBMT statistically increased the [O2Hb] in 0.39 µM. These results demonstrate the potential of PBMT to increase oxygen availability.
Asunto(s)
Hemoglobinas/metabolismo , Terapia por Luz de Baja Intensidad , Espectroscopía Infrarroja Corta , Adulto , Humanos , Masculino , Músculo Esquelético/fisiología , Oxihemoglobinas/metabolismo , PlacebosRESUMEN
Uma das principais doenças do sistema cardiovascular é conhecida como Doença Arterial Coronariana (DAC) e é a causa mais comum de morte nos países desenvolvidos e em desenvolvimento em todo o mundo. Existem alguns fatores de risco diretamente relacionados com a progressão e as complicações da aterosclerose e a associação entre estes fatores modificáveis ou não, tem efeito cumulativo; portanto, quanto maior o número e intensidade de aparecimento, maior a incidência de DAC...