Muscle Oxygenation of the Paretic and Nonparetic Legs During and After Arterial Occlusion in Chronic Stroke.

Oxygen delivery and demand are reduced in the paretic leg post-stroke, reflecting decreased vascular function and reduced muscle quantity and quality. However, it is unknown how muscle oxygenation, the balance between muscle oxygen delivery and utilization, is altered in chronic stroke during and after occlusion-induced ischemia. OBJECTIVES: The objective was to determine muscle oxygen consumption rate, microvascular responsiveness and reactive hyperemia in the paretic and nonparetic legs during and after arterial occlusion post-stroke. MATERIALS AND METHODS: Muscle oxygen saturation was measured with near-infrared spectroscopy on the vastus lateralis of each leg during 3-minute arterial occlusion and recovery (3 min). Muscle oxygen consumption was derived from the desaturation slope during ischemia, microvascular responsiveness was derived from the resaturation slope after ischemia and reactive hyperemia was derived from the area under the curve above baseline after ischemia. RESULTS: Eleven subjects (91% male; 32.2±6.1 months post-stroke; age 62.9±13.6 years) with a hemiparetic gait pattern participated. There was no significant between-leg muscle oxygenation difference at rest (paretic: 64.9±16.6%; nonparetic: 70.6±15.6%, p = 0.13). Muscle oxygen consumption in the paretic leg (-0.53±0.24%/s) was significantly reduced compared to the nonparetic leg (-0.70±0.36%/s; p = 0.03). Microvascular responsiveness was significantly reduced in the paretic leg compared to the nonparetic leg (paretic: 4.6±1.8%/s; nonparetic: 5.7±1.6%/s, p = 0.04). Reactive hyperemia was not significantly different between legs (paretic:4384±2341%·s; nonparetic: 3040±2216%·s, p = 0.07). CONCLUSION: Muscle oxygen consumption and microvascular responsiveness are impaired in the paretic compared to the nonparetic leg, suggesting both reduced skeletal muscle aerobic function and reduced ability to maximally perfuse muscle tissue.

Kinesiologists in Clinical Exercise Interventional Research for Stroke and Coronary Artery Disease: A Scoping Review.

Background: Kinesiology contributions to research and implementation of programs for cardiovascular disease have not been documented. This scoping review assesses kinesiology affiliates participation in exercise interventional research. Methods: The review followed the Preferred Reporting Items for Systematic review and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) Checklist. Eligible studies included individuals diagnosed with coronary artery (CAD) or heart disease (CHD) or stroke participating in exercise interventions supervised or designed by a kinesiologist affiliate (exercise physiologist, kinesiologist, exercise trainer, exercise therapist). Results: The search in MEDLINE, Embase, Scopus, PsychINFO, SPORTDiscus, and CINAHL yielded 219 studies, including 13,874 participants (5,242 CAD, 4,526 CHD, and 4,106 post-stroke). Randomized controlled trials were the most common study design (52%). Kinesiologists were involved in 70% of the studies and supervised 23%. Forty percent did not specify the supervisor. Kinesiologists are involved in prevention and rehabilitation exercise studies that look to improve feasibility of practice, aerobic fitness, muscle and body composition, functional capacity, gait, neurological, psychosocial, and cardiovascular outcomes. Conclusions: Documentation of kinesiology contributions to research for patients with cardiovascular disease may enhance their acceptance in research and care for people with impaired cardiovascular health.

Kinesiology affiliates frequently implement and supervise clinical exercise interventions in stroke, CAD, and CHD populationsKinesiology affiliates make contributions to high-quality evidence generating research and patient careClinical exercise intervention supervisors are often kinesiology affiliates but are not identified in 40% of research reports.

Muscle oxygenation of the paretic and nonparetic legs during and after exercise in chronic stroke: Implications for mobility.

BACKGROUND: Oxygen delivery and demand are reduced in the paretic leg of individuals after stroke. However, it is unknown how muscle oxygenation, the balance between delivery and utilization of oxygen at the muscle, is altered post-stroke during aerobic exercise and how it relates to mobility. OBJECTIVE: To monitor muscle oxygenation changes between the paretic and nonparetic legs of individuals after stroke during treadmill exercise and the 6-minute walk test and analyze the association with mobility. DESIGN: Cross-sectional study. SETTING: Cardiac rehabilitation program. PATIENTS: Eleven male participants were enrolled in the study. Ten men (30.8 ± 4.1 months post-stroke; age 63.9 ± 13.9 years) with hemiparetic gait pattern finished the study. METHODS OR INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Muscle oxygenation was measured with near-infrared spectroscopy placed on the vastus lateralis of each leg during treadmill exercise at the first ventilatory threshold and during a 6-minute walk test. RESULTS: The desaturation slope during treadmill exercise was significantly steeper (p = .047) in the paretic (-0.7 ± 0.6%/s) compared to the nonparetic leg (-0.3 ± 0.2%/s). There was no other significant difference between legs. The 6-minute walk test distance was not correlated with 6-minute walk test muscle oxygenation in either leg (paretic: r = 0.20, p = 0.590; nonparetic: r = 0.42, p = .232). CONCLUSIONS: At the onset of treadmill exercise, the paretic leg was unable to effectively match the oxygen demand and extraction of the nonparetic leg, suggesting the need for an immediate cardiovascular warmup prior to initiating moderate intensity exercise in this population. Because the exercise desaturation rate is thought to indicate increased anaerobic metabolism and lactate production, efforts to delay rapid desaturation could improve the sustainability of activities of daily living and exercise.

Update on Current Evidence for the Diagnosis and Management of Nonfunctioning Pituitary Neuroendocrine Tumors.

Pituitary neuroendocrine tumors (PitNETs) are the third most frequently diagnosed intracranial tumors, with nonfunctioning PitNETs (nfPitNETs) accounting for 30% of all pituitary tumors and representing the most common type of macroPitNETs. NfPitNETs are usually benign tumors with no evidence of hormone oversecretion except for hyperprolactinemia secondary to pituitary stalk compression. Due to this, they do not typically present with clinical syndromes like acromegaly, Cushing's disease or hyperthyroidism and instead are identified incidentally on imaging or from symptoms of mass effects (headache, vision changes, apoplexy). With the lack of effective medical interventions, first-line treatment is transsphenoidal surgical resection, however, nfPitNETs often have supra- or parasellar extension, and total resection of the tumor is often not possible, resulting in residual tumor regrowth or reoccurrence. While functional PitNETs can be easily followed for recurrence using hormonal biomarkers, there is no similar parameter to predict recurrence in nfPitNETs, hence delaying early recognition and timely management. Therefore, there is a need to identify prognostic biomarkers that can be used for patient surveillance and as therapeutic targets. This review focuses on summarizing the current evidence on nfPitNETs, with a special focus on potential new biomarkers and therapeutics.