Neurogenic Orthostatic Hypotension. Lessons From Synucleinopathies.

Maintenance of upright blood pressure critically depends on the autonomic nervous system and its failure leads to neurogenic orthostatic hypotension (NOH). The most severe cases are seen in neurodegenerative disorders caused by abnormal α-synuclein deposits: multiple system atrophy (MSA), Parkinson's disease, Lewy body dementia, and pure autonomic failure (PAF). The development of novel treatments for NOH derives from research in these disorders. We provide a brief review of their underlying pathophysiology relevant to understand the rationale behind treatment options for NOH. The goal of treatment is not to normalize blood pressure but rather to improve quality of life and prevent syncope and falls by reducing symptoms of cerebral hypoperfusion. Patients not able to recognize NOH symptoms are at a higher risk for falls. The first step in the management of NOH is to educate patients on how to avoid high-risk situations and providers to identify medications that trigger or worsen NOH. Conservative countermeasures, including diet and compression garments, should always precede pharmacologic therapies. Volume expanders (fludrocortisone and desmopressin) should be used with caution. Drugs that enhance residual sympathetic tone (pyridostigmine and atomoxetine) are more effective in patients with mild disease and in MSA patients with spared postganglionic fibers. Norepinephrine replacement therapy (midodrine and droxidopa) is more effective in patients with neurodegeneration of peripheral noradrenergic fibers like PAF. NOH is often associated with other cardiovascular diseases, most notably supine hypertension, and treatment should be adapted to their presence.

Prueba de inclinación, Head-up tilt test, lecciones aprendidas en 564 casos consecutivos / Head-up tilt test, lessons learned from 564 consecutive cases

Introducción. El síncope es un motivo frecuente de consulta; el mecanismo causal más común es el reflejo, que incluye el síncope neurocardiogénico, SN, la hipotensión ortostática, la hipersensibilidad del seno carotídeo, entre otros. Estas variantes se valoran mediante la prueba de inclinación, con o sin estímulo farmacológico con nitroglicerina. El presente estudio recoge la experiencia con este examen auxiliar realizado en nuestro centro en los últimos 8 años. Material y métodos. Es un estudio retrospectivo, en el que se analizaron los resultados de las pruebas de inclinación realizadas a los pacientes que fueron referidos consecutivamente a nuestro centro en el período julio 2003 - agosto 2010. La información se obtuvo de la base de datos electrónica, así como del interrogatorio de los síntomas que motivaron la solicitud de la prueba. Resultados. Se incluyeron los datos de 564 pruebas de inclinación; la edad promedio fue 36.33 más menos 18.4 años, 6-89, a predominio el sexo femenino, 373, hombres 191. El motivo de realización de la prueba fue: historia de síncope, 67 por ciento, lipotimia, 26 por ciento, y otros. El examen fue anormal en 470 pacientes, 92 negativos, sensibilidad global 83.6, y los diagnósticos fueron: 118 SN tipo vasodilatador, 25 por ciento, 112 SN tipo cardioinhibitorio, 24 por ciento, y 157 SN de tipo mixto, 33 por ciento; 60 pacientes presentaron taquicardia postural ortostática, 12 por ciento, y 24 hipotensión ortostática, 5 por ciento, 9 de los cuales tenía tratamiento farmacológico antihipertensivo; edad promedio 64 años. En 11 pacientes, 2.3 por ciento, se documentó hipersensibilidad del seno carotídeo, 9 de los cuales presentó también alguna forma de SN, edad promedio 60.63 años. Conclusión. La prueba de inclinación es adecuadamente sensible para la valoración del paciente que se presenta con síncope, en especial, en pacientes jóvenes sin evidencia de cardiopatía estructural. El SN es la disautonomía más frecuente y es más prevalente en mujeres pero más pronunciado en hombres, mientras que la hipotensión ortostática y la hipersensibilidad del seno carotídeo predomina en personas mayores.

Orthostatic hypotension: a common, serious and underrecognized problem in hospitalized patients.

Orthostatic hypotension (OH) is strongly age-dependent, with a prevalence ranging from 5% to 11% in middle age to 30% or higher in the elderly. It is also closely associated with other common chronic diseases, including hypertension, congestive heart failure, diabetes mellitus, and Parkinson's disease. Most studies of OH have been performed in population cohorts or elderly residents of extended care facilities, but in this review, we draw attention to a problem little studied to date: OH in hospitalized patients. The prevalence of OH in all hospitalized patients is not known because most studies have included only older individuals with multiple comorbid diseases, but in some settings as many as 60% of hospitalized adults have postural hypotension. Hospitalized patients are particularly vulnerable to the consequences of OH, particularly falls, because postural blood pressure (BP) regulation may be disturbed by many common acute illnesses as well as by bed rest and drug treatment. The temporal course of OH in hospitalized patients is uncertain, both because the reproducibility of OH is poor and because conditions affecting postural BP regulation may vary during hospitalization. Finally, OH during hospitalization often persists after discharge, where, in addition to creating an ongoing risk of falls and syncope, it is strongly associated with risk of incident cardiovascular complications, including myocardial infarction, heart failure, stroke, and all-cause mortality. Because OH is a common, easily diagnosable, remediable condition with important clinical implications, we encourage caregivers to monitor postural BP change in patients throughout hospitalization.

Marca-passo atrial no tratamento da hipotensão ortostática primária / Atrial pacemaker for treating primary orthostatic hypotension

Homem, 78 anos, com hipotensão ortostática neurogênica incapacitante não responsiva e terapêutica clássica, admitido em hospital para implantação de marca-passo atrial programável. Inicialmente, implantou-se marca-passo atrial temporário, a frequencia de 96 bpm (dia) e 60 bpm (noite). Observou-se melhora dos sintomas, justificando a implantação de marca-passo definitivo. Recomenda-se considerar esta modalidade terapeutica em idosos com hipotensão ortostática neurogênica sem taquicardia compensatória quando não houver resposta a tratamento clássico.

A 78-year-old male patient with incapacitating neurogenic orthostatic hypertension was admitted in hospital for implantation of programmable pacemaker after no response to classic treatment. The initial procedure consisted in implanting a temporary pacemaker at a frequency of 96 BPM in the morning and 60 BPM at night. A definitive pacemaker was implanted because of the improvement of symptoms. Such treatment modality is herein recommended for elderly patients suffering from neurogenic orthostatic hypotension without compensatory tachycardia when they show no positive response to the classic treatment.

Improving idiophatic orthostatic hypotension in a patient with multiple system atrophy (Shy-Drager syndrome) with cardiac pacemaker implantation: case report / Melhora da hipotensão ortostática em um paciente com atrofia de múltiplos sistemas (syndrome de Shy-Drager) com implantação de marca-passo cardíaco: relato de caso

Orthostatic hypotension is a frequent symptom in patients with multiple system atrophy and it has an important impact on their quality of life. We report a case of idiopathic orthostatic hypotension, in a patient with multiple system atrophy (Shy-Drager syndrome), treated with pacemaker implantation resulting in a substantial improvement in the quality of his life.

Hipotensão ortostática é um sintoma freqüente em pacientes com atrofia de múltiplos sistemas e tem importante impacto na sua qualidade de vida. Relatamos um paciente com hipotensão ortostática idiopática e atrofia de múltiplos sistemas (Síndrome de Shy-Drager), tratado com implantação de marca-passo resultando numa evidente melhora na qualidade de vida.

Brazilian dentists' attitudes about medical emergencies during dental treatment.

The main objective of this study was to evaluate the prevalence of emergencies in dental practices and the prepared-ness and the training experience in cardiopulmonary resuscitation (CPR) of Brazilian dentists in dealing with emergencies. The volunteer participants in the study were 498 Brazilian dentists who were present at the 27th International Congress of Dentistry in São Paulo. The most prevalent emergency was presyncope (reported by 54.20 percent of respondents), followed by orthostatic hypotension (44.37 percent), moderate allergic reactions (16.86 percent), hypertensive crisis (15.06 percent), asthma (15.06 percent), syncope (12.65 percent), angina (6.82 percent), convulsion (6.22 percent), hypoglycemia (5.62 percent), hyperventilation crisis (5.22 percent), choking (2.20 percent), and cerebrovascular accident (0.8 percent). Anaphylaxis, myocardial infarction, and cardiac arrest were the rarest emergencies, reported by only 0.4, 0.2, and 0.2 percent of dentists, respectively. Only 41 percent of the dentists judged themselves capable to diagnose the cause of an emergency during a dental visit. The majority responded that they would be capable of performing initial treatment of presyncope, syncope, orthostatic hypotension, convulsion, and choking. However, most of them felt unable to treat anaphylaxis, myocardial infarction, or cardiac arrest. Further, the majority felt unable to perform CPR or undertake an intravenous injection. It was concluded that the most prevalent medical emergencies in dental practice of Brazilian dentists are presyncope and orthostatic hypotension. The occurrence of life-threatening medical emergencies like anaphylaxis, myocardial infarction, cardiac arrest, and cerebrovascular accident is rare. Brazilian dentists are not fully prepared to manage medical emergencies and have insufficient experience training in CPR.

Síncope vasovagal e suplementação de sal: [revisão] / Vasovagal syncope and salt supplementation: [review]

Síncope é definida como uma perda súbita e breve da consciência e do tônus postural devido à hipoperfusão cerebral. A síncope vasovagal é a causa mais comum de síncope entre todas as etiologias. A incidência pode variar de 21 a 35%, acometendo geralmente pessoas jovens e saudáveis. A fisiopatologia da síncope vasovagal não está completamente esclarecida, contudo, pode ser explicada por vasodilatação e bradicardia reflexo-mediada. Estudos vêm sendo desenvolvidos na tentativa de se encontrar melhores formas de abordagem terapêutica para essa disautonomia, muitas vezes resistente aos tratamentos propostos. Agentes farmacológicos são utilizados, mas a eficácia é questionável e os efeitos adversos são comuns. Até o momento, dispõe-se de poucos estudos randomizados os quais envolvem, na maioria das vezes, pequeno número de pacientes. Medidas terapêuticas têm sido propostas para prevenção de recorrências, como orientações gerais não farmacológicas, reconhecimento dos pródromos e fatores desencadeantes, programas de treinamento fisico e postural, aumento da ingestão hídrica e de sal. Alguns achados sugerem que exista influência da suplementação de sal em parâmetros clínicos da síncope vasovagal. O mecanismo pelo qual a administração de sal previne a síncope não é bem conhecido, embora sua eficácia seja atribuída à expansão de volume extracelular. A suplementação de sal pode aumentar o peso corpóreo, o volume plasmático, a tolerância ortostática e a pressão arterial na posição ortostática. Entretanto, um subgrupo específico de pessoas nas quais os sintomas não são devidamente controlados necessita de intervenção farmacológica e não farmacologia. Em geral, obtêm-se bons resultados terapêuticos com mudanças nos hábitos alimentares e comportamentais.

Syncope is defined as a sudden and brief loss of consciousness and postural tonus due to cerebral hypoperfusion. Vasovagal syncope is the most common cause of syncope among all etiologies. The incidence may range from 21 to 35% and this condition usually affects young, healthy people. Its pathophysiology has not been elucidated yet, and it may due to vasodilation and reflex-mediated bradycardia. Some studies have been carried out as an attempt to find better therapeutic approaches for this dysautonomy which is often resistant to the treatments suggested. Pharmacological agents have been used, but the efficacy has not been fully proven and adverse effects are common. Currently, there are few randomized studies and most of them involve small samples. Therapeutic measures have been suggested to prevent relapses, including general non-pharmacological approaches such as recognizing the symptoms and the triggering factors, programs of physical and postural training, increase in the water and salt intake. Some findings suggest there is an influence of salt supplementation in the clinical parameters of vasovagal syncope. The mechanism that prevents syncope using salt administration has not been completely understood, although its efficacy is attributed to the expansion of the extracellular volume. Salt supplementation can increase body weight, plasma volume, orthostatic tolerance and blood pressure in the upright posture. However, a specific subgroup of people who presents with symptoms that are not appropriately controlled need intervention pharmacological and non pharmacology. In general, good therapeutic results are achieved with changes in diet and behavior.

Abordagem das hipotensões ortostática / Management of orthostatic and postprandial hypotension

A prevalência de hipotensão ortostática e pós-prandial é elevada na população idosa, estando muito associado à disautonomia. As manifestações clínicas variam de sintomas inespecíficos e tontura até casos de síncope acompanhados de trauma. O diagnóstico é clínico, estabelecido por meio de anamnese detalhada e exame físico. Monitorização ambulatorial da pressão arterial (MAPA) e tilt-test são complementares em situações específicas. O tratamento é feito com base em medidas como suspensão de medicamentos hipotensores, cuidados posturais e relacionados à ingestão alimentar. A droga de escolha é a fludrocortisona, um esteróide adrenocortical com propriedades mineralocorticóides. Agentes simpaticomiméticos são uma segunda opção. A individualização de condutas é essencial, uma vez que a presença de comorbidades limita o emprego de determinadas diretrizes.

Hipertensão arterial no idoso: peculiaridades na fisiopatologia, no diagnóstico e no tratamento / Arterial Hypertension in the elderly: peculiarities of physiopathology, diagnostics, and treatment

A HAS em idosos está associada a um importante aumento nos eventos cardiovasculares com consequente diminuição da sobrevida e piora na qualidade de vida. Inumeros estudos demonstraram os beneficios do tratamento da HAS na população desta faixa etaria, com redução significativa dos eventos cardiovasculares e melhora na qualidade de vida. Tanto o tratamento medicamentoso como o não-farmacologico devem ser empregados, sempre considerando o individuo com suas co-morbidades e expectativas. As modificações de estilo de vida podem ter otima aderencia desde que bem orientadas, especialmente atraves de equipe multidisciplinar. O uso da terapia farmacologica combinada (duas drogas no mesmo comprimido) é uma necessidade para os idosos, melhorando a aderencia e a eficacia anti-hipertensiva e diminuindo os efeitos colaterais. Existem varios casos não contemplados nos grandes ensaios, por exemplo os idosos frageis ou os muito idosos, em que o tratamento deve ser feito com bom senso e de forma individualizada

Orthostatic hypotension, 2001.

Upright posture requires rapid and effective circulatory and neurologic compensations to maintain blood pressure and consciousness. Although it has been recognized over the past 100 years or more that the act of standing may cause hypotension in patients with autonomic dysfunction, only recently several of the pathophysiologic mechanisms resulting in orthostatic intolerance have been discovered. In patients with orthostatic hypotension, failure of reflex vasoconstriction causes pooling of blood in the legs during standing. Not everyone with a postural blood pressure drop requires treatment, nor does everyone with posturally induced symptoms have orthostatic hypotension. This review will discuss current knowledge of a broad, heterogeneous group of disturbances in the autonomic nervous system, each of which is manifested by hypotension, orthostatic intolerance, and often syncope.

[Programmed atrial pacemaker in the treatment of neurogenic orthostatic hypotension in the elderly]. / Marcapasso atrial programável no tratamento da hipotensão ortostática neurogênica no idoso.

A programmable atrial pacemaker was implanted in an elderly man, 75 years-old, with incapacitating orthostatic hypotension due to automatic dysfunction (Shy-Drager) unresponsive to traditional therapy. Initially, a temporary programmed atrial pacing was implanted paced at 96 beats/minute during the day, reducing the rate at night to 60 betas/minute. An increase in cardiac output was achieved. Favourable results encouraged us to implant a permanent programmed pacemaker. The manufacturer designed a simple, safe programmer operable by the patient which only alters the rate from night (60) to day (96). A marked improvement in symptoms has been observed during a follow-up of nine months without complications. It is recommended that this sort of treatment be considered in elderly patients with symptomatic orthostatic hypotension due to autonomic dysfunction with inadequate compensatory tachycardia who have not responded to traditional therapy.