RESUMO
BACKGROUND: Idiopathic intracranial hypertension is a disease characterized by increased intracranial cerebrospinal fluid volume and pressure without evidence of other intracranial pathology. Dural sinuses are rigid structures representing a privileged low-pressure intracranial compartment. Rigidity of dural sinus ensures that the large physiologic fluctuations of cerebrospinal fluid pressure associated with postural changes or to Valsalva effect cannot be transmitted to the sinus. An abnormal dural sinus collapsibility, especially when associated with various anatomical sinus narrowing, has been proposed as a key factor in the pathogenesis of idiopathic intracranial hypertension. This pathogenetic model is based on an excessive collapsibility of the dural sinuses that leads to the triggering of a self-limiting venous collapse positive feedback-loop between the cerebrospinal fluid pressure, that compresses the sinus, and the increased dural sinus pressure upstream, that reduces the cerebrospinal fluid reabsorption rate, increasing cerebrospinal fluid volume and pressure at the expense of intracranial compliance and promoting further sinus compression. Intracranial compliance is the ability of the craniospinal space to accept small volumetric increases of one of its compartments without appreciable intracranial pressure rise. In idiopathic intracranial hypertension, a condition associated with a reduced rate of CSF reabsorption leading to its volumetric expansion, a pathologically reduced IC precedes and accompanies the rise of ICP. Syncope is defined as a transient loss of consciousness due to a transient cerebral hypoperfusion characterized by rapid onset, short duration, and spontaneous complete recovery. A transient global cerebral hypoperfusion represents the final mechanism of syncope determined by cardiac output and/or total peripheral resistance decrease. There are many causes determining low cardiac output including reflex bradycardia, arrhythmias, cardiac structural disease, inadequate venous return, and chronotropic and inotropic incompetence. Typically, syncopal transient loss of consciousness is mainly referred to an extracranial mechanism triggering a decrease in cardiac output and/or total peripheral resistance. Conversely, the association of syncope with a deranged control of intracranial compliance related to cerebral venous outflow disorders has been only anecdotally reported. CASE PRESENTATION: We report on a 57-year-old woman with daily recurrent orthostatic hypotension syncope and idiopathic intracranial hypertension-related headaches, which resolved after lumbar puncture with cerebrospinal fluid subtraction. CONCLUSIONS: A novel mechanism underlying the triggering of orthostatic syncope in the presence of intracranial hypertension-dependent reduced intracranial compliance is discussed.
Assuntos
Hipertensão Intracraniana , Pseudotumor Cerebral , Feminino , Humanos , Pessoa de Meia-Idade , Pseudotumor Cerebral/complicações , Punção Espinal , Hipertensão Intracraniana/complicações , Síncope , ReflexoRESUMO
Modifications of lean mass are a frequent critical determinant in the pathophysiology and progression of heart failure (HF). Sarcopenia may be considered one of the most important causes of low physical performance and reduced cardiorespiratory fitness in older patients with HF. Sarcopenia is frequently misdiagnosed as cachexia. However, muscle wasting in HF has different pathogenetic features in sarcopenic and cachectic conditions. HF may induce sarcopenia through common pathogenetic pathways such as hormonal changes, malnutrition, and physical inactivity; mechanisms that influence each other. In the opposite way, sarcopenia may favor HF development by different mechanisms, including pathological ergoreflex. Paradoxically, sarcopenia is not associated with a sarcopenic cardiac muscle, but the cardiac muscle shows a hypertrophy which seems to be "not-functional." First-line agents for the treatment of HF, physical activity and nutritional interventions, may offer a therapeutic advantage in sarcopenic patients irrespective of HF. Thus, sarcopenia is highly prevalent in patients with HF, contributing to its poor prognosis, and both conditions could benefit from common treatment strategies based on pharmacological, physical activity, and nutritional approaches.
Assuntos
Insuficiência Cardíaca/fisiopatologia , Sarcopenia/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Coração/fisiopatologia , Insuficiência Cardíaca/complicações , Humanos , Hipertrofia , Masculino , Músculo Esquelético/fisiopatologia , Atrofia Muscular/etiologia , Atrofia Muscular/fisiopatologia , Estado Nutricional , Prognóstico , Sarcopenia/etiologiaRESUMO
Treatment for chronic heart failure (CHF) is strongly focused on evidence-based medicine. However, large trials are often far away from the "real world" of geriatric patients and their messages are poorly transferable to the clinical management of CHF elderly patients. Precipitating factors and especially non-cardiac comorbidity may decompensate CHF in the elderly. More importantly, drugs of first choice, such as angiotensin-converting enzyme inhibitors and ß-blockers, are still underused and effective drugs on diastolic dysfunction are not available. Poor adherence to therapy, especially for cognitive and depression disorders, worsens the management. Electrical therapy is indicated, but attention to the older age groups with reduced life expectancy has to be paid. Physical exercise, stem cells, gene delivery, and new devices are encouraging, but definitive results are still not available. Palliative care plays a key role to the end-stage of the disease. Follow-up of CHF elderly patient is very important but tele-medicine is the future. Finally, self-care management, caregiver training, and multidimensional team represent the critical point of the treatment for CHF elderly patients.
Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Adesão à Medicação , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Doença Crônica , Quimioterapia Combinada , Medicina Baseada em Evidências , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Humanos , Obesidade/complicações , Cuidados Paliativos/métodos , Guias de Prática Clínica como Assunto , Fatores de Risco , Autocuidado , Resultado do Tratamento , Redução de PesoRESUMO
A mild stress such as brief ischemic episodes may protect the heart from a successive and more prolonged myocardial ischemia (ischemic preconditioning). This phenomenon is considered a typical "hormetic mechanism" by which the heart is immunized from pathological insults such as myocardial ischemia. This mechanism is reduced with aging and it may be restored and/or preserved by drugs such as adenosine or nicorandil, a mitochondrial K(ATP) channels, and lifestyle interventions such as physical activity and/or hypocaloric diet. Moreover, since the mechanisms involved in cardiac ischemic preconditioning have been established basic and clinical investigators are encouraged to test several drug in well-controlled animal and human studies in order to prevent and/or restore the age-related reduction of ischemic preconditioning.
RESUMO
The life span of human beings is partially influenced by genetic factors, but outcomes of aging are profoundly influenced by lifestyle and other environmental factors. Age-related modifications of the cardiovascular system are preserved by antiaging lifestyle interventions such as physical activity and caloric restriction. Accordingly, physical activity and low body mass index reduce mortality in older men with cardiovascular diseases. Several mechanisms have been proposed to explain the protective effect of lifestyle interventions against cardiovascular diseases in the elderly, including a reduction of vulnerability (i.e., the age-related reduction of endogenous mechanisms protective against pathologic insults). The age-related reduction of ischemic preconditioning, the most powerful endogenous protective mechanism against myocardial ischemia, is restored by both physical activity and caloric restriction. Thus, older persons can implement lifestyle practices that minimize their risk of death from cardiovascular diseases.