Orthostatic Hypotension Test Research Articles

Differential response of macular and disc capillaries in response to the orthostatic hypotension test

Aims/Purpose: To investigate the effect of the orthostatic hypotension test on the macular and disc capillaries, in subjects with different blood pressure (BP) status.Methods: We prospectively recruited ophthalmologically healthy subjects (age 50–65) from a large‐scale population‐based Dutch cohort. We allocated participants to four groups: low BP, normal BP, treated high BP, and untreated high BP. We obtained two 6x6 mm macular and two 6x6 mm disc OCTA scans of the superficial capillaries. After lying for 5 min, participants stood up for 3 min, following which third scans were obtained from both regions. We quantified vessel density (VD) using customized software. We used linear mixed models to compare VD among groups before and after the orthostatic hypotension test.Results: We included 98 eyes from 98 subjects for the macular scans and 95 for the disc scans. Parafoveal VD was similar between groups (p = 0.65) and increased following the orthostatic hypotension test (40.4%, 40.6% pre‐test and 40.7% post‐test; p = 0.002). Post hoc analysis revealed that this difference was only significant between the first and third scan (p = 0.001). Peripapillary VD remained unchanged pre‐ and post‐test (p = 0.61), but differed between groups (low BP: 44.0%, normal BP: 45.0%, treated high BP: 44.1%, untreated high BP: 44.5%; p = 0.022). Post hoc analysis revealed that these differences were significant between normotensives and subjects with low BP (p = 0.028) and borderline between normotensives and subjects with treated high BP (p = 0.072).Conclusions: We observed an autoregulatory response of macular, but not disc, capillaries, following BP drop due to the orthostatic hypotension test.

Assessment of cardiovascular sympathetic function tests in premenstrual syndrome patients visiting tertiary care hospital: A case–control study

Background: Premenstrual syndrome (PMS) is a stress-induced disorder and is showing a rising prevalence but its etiopathogenesis is not yet understood. Stress disturbs the balance of the sympathetic and parasympathetic nervous system. Alteration in heart rate and blood pressure is the most important physiological response following stress-induced sympathetic changes. Aims and Objectives: The present study was designed to test the hypothesis of an association between sympathetic functions and PMS and to observe the degree of changes (if any) in these sympathetic functions. The study also aims to provide timely interventions to prevent the development of cardiovascular complications and improve lifestyle. Materials and Methods: A Menstrual Distress Questionnaire was used to evaluate physical, emotional, and behavioral symptoms accompanying the menstrual cycle of the subjects who fulfilled the inclusion criteria. Based on the scores obtained by their questionnaire, subjects with the higher scores formed the PMS group, while the age-matched females with low score served as controls. Cardiovascular sympathetic functions were assessed by standardized, simple, non-invasive tests which included Handgrip test and orthostatic hypotension test. Unpaired Student’s t-test was used for statistical analysis. Results: The results revealed that the sympathetic reactivity is insignificantly higher in PMS group during the follicular phase. During the luteal phase, sympathetic activity is significantly increased. Conclusion: PMS involves psychoneuroendocrinal turmoil, thus early screening of high-risk groups and interventions such as relaxation techniques and lifestyle modification can prevent further cardiovascular complications in patients of high sympathetic responses.

Autonomic nervous system dysfunction correlates with microvascular damage in systemic sclerosis patients.

Cardiac autonomic neuropathy is among the known cardiovascular complications of systemic sclerosis and may affect the whole prognosis of the disease. The aim of our study was to assess cardiac autonomic neuropathy prevalence in our cohort of systemic sclerosis patients and compare its main features with clinical and epidemiological data, particularly with the severity of microvascular damage, as detected by nailfold videocapillaroscopy. Twenty-six patients with definite systemic sclerosis were consecutively enrolled at our outpatient rheumatology clinic. All patients underwent physical examination, nailfold videocapillaroscopy, and autonomic neuropathy diagnostic tests (orthostatic hypotension test, deep breathing test, lying-to-standing, and Valsalva maneuvers). Cardiac autonomic neuropathy prevalence was 50% (13 cases). On univariate analysis, cardiac autonomic neuropathy was shown to be significantly associated with an active pattern on nailfold videocapillaroscopy (odds ratio 5.86, 95% confidence interval 1.59-9.24; p = 0.032), whereas anti-Scl-70 positivity (odds ratio, 0.24; 95% confidence interval, 0.03-2.12; p = 0.049) and C-reactive protein (odds ratio, 19.32; 95% confidence interval, 1.79-56.71; p = 0.036) reached only a borderline statistical association. The time-dependent Cox multivariate regression model showed cardiac autonomic neuropathy development to be independently associated with an active pattern on nailfold videocapillaroscopy (odds ratio, 7.19; 95% confidence interval, 1.87-8.96; p = 0.042) and anti-Scl-70 positivity (odds ratio, 5.92; 95% confidence interval, 1.06-18.43; p = 0.048). Severe microvascular damage, as detected by nailfold videocapillaroscopy, may suggest the coexistence of autonomic dysfunction and should be considered as a red flag for the identification of patients particularly at risk of cardiac morbidity and mortality.

Abstract P028: Increased Cardiometabolic Risk And Autonomic Function Alterations In Normal Weight Obesity

Introduction: Normal weight obesity (NWO) is defined by the presence of normal body mass index (BMI) with high body fat percentage. In this setting, high body fat seems to affect even non-obese individuals, predicting cardiovascular risk. Hypothesis: High body fat percentage, in eutrophic individuals, affects anthropometry, hemodynamic, autonomic function and cardiometabolic risk. Methods: This cross-sectional study recruited workers of a public hospital from 2018 to 2020. Inclusion criteria: age ≥ 18 yr.; BMI: 18.5 to 24.9 Kg/m 2 . Exclusion criteria: pregnancy/lactating women; BMI < 18.5 Kg/m 2 or ≥ 25 Kg/m 2 . High body fat percentage was categorized, by sex and age, as: 20 to 39 years, >19.9% and >32.9%; 40 to 59 years, >21.9% and >33.9%; and 60 to 79 years, >24.9% and >35.9% for men and women, respectively. Blood assays: fasting glucose, lipid profile and C reactive protein; anthropometry: neck, waist and hip circumferences; bioimpedance: visceral fat area and body fat percentage; hemodynamic parameters: blood pressure and double product; autonomic function: orthostatic test (30:15 ratio), orthostatic hypotension test and heart rate variability (HRV): high and low frequency and sympathovagal index; cardiometabolic risk: body shape index, atherogenic dyslipidemia, atherogenic index, atherogenic index of plasma and Framingham score. Statistical analysis: Mann-Whitney and chi-squared test. P<0.05. Ethics: according to Helsinki declaration, revised in 2013. Results: A total of 52 from 241 volunteers were eutrophic: 23 were NWO, that exhibited higher visceral fat area, anthropometric measures, blood pressure and double product; and worse lipid profile, HRV frequency domain and cardiometabolic risk parameters compared to the 29 with normal body fat percentage (table 1) . Conclusions: NWO individuals have metabolic, hemodynamic, anthropometric and autonomic alterations that, associated with new indexes related to atherogenesis, confirm the early cardiometabolic risk of this profile.

An Effectiveness Trial of STEADI in an Outpatient, Primary Care Practice

The STEADI Options trial uses a randomized, controlled-trial design to assess the effectiveness and cost-effectiveness of the STEADI Initiative . Beginning March, 2020, we will randomize 3,000 adults ≥ 65 years of age at risk for falls seen in an Emory Clinic primary care practice to: (1) full STEADI; (2) a STEADI-derived gait, balance, and strength assessment with physical therapy referrals; (3) a STEADI-derived medication review and management; or (4) usual care. This presentation will discuss decisions made by the study team to facilitate implementation of STEADI including electronically conducting screening prior to the date of encounter, the use of dedicated nursing staff to conduct assessments, implementation of strength, balance, orthostatic hypotension, and vision testing, methods to facilitate medication review, and communication of assessment information to providers. The results from this study will be used to estimate the impact of STEADI on falls, service utilization, and costs over one year.

Time point of blood pressure drop in patients with orthostatic hypotension in the emergency department.

The purpose of this study was to identify the time of blood pressure (BP) drop in the orthostatic hypotension test, and to propose a realistic and appropriate duration in the orthostatic hypotension test. A total of 879 consecutive patients (61-year-old and 44% women) with positive on the orthostatic hypotension test in the emergency department were retrospectively reviewed. Orthostatic hypotension was defined as drop in standing SBP of at least 20 mmHg or standing DBP of at least 10 mmHg from their supine values after standing for 5 min. BP measurements was made at 1, 3, and 5 min after standing. Six hundred and eighty-four (77.8%), 152 (17.3%) and 43 (4.9%) patients had BP drop meeting orthostatic hypotension criteria at 1, 3, and 5 min, respectively. In multivariable analysis, older age (≥60 years) and higher blood urea nitrogen (BUN) (≥15.5 mg/dl) were independently associated with early BP drop at 1 min, and younger age (<40 years) was independently associated with later BP drop at 5 min even after controlling for potential confounders. To measure orthostatic BP for orthostatic hypotension diagnosis at emergency department, older patients (≥60 years) with high BUN (≥15.5 mg/dl) should be monitored carefully as BP can drop quickly within 1 min. On the contrary, in younger people (<40 years), BP drop occurred slowly after 3 min, suggesting that clinicians measure BP for a longer time.

Pressure Autoregulation Measurement Techniques in Adult Traumatic Brain Injury, Part I: A Scoping Review of Intermittent/Semi-Intermittent Methods.

The purpose of this study was to perform a systematic, scoping review of commonly described intermittent/semi-intermittent autoregulation measurement techniques in adult traumatic brain injury (TBI). Nine separate systematic reviews were conducted for each intermittent technique: computed tomographic perfusion (CTP)/Xenon-CT (Xe-CT), positron emission tomography (PET), magnetic resonance imaging (MRI), arteriovenous difference in oxygen (AVDO2) technique, thigh cuff deflation technique (TCDT), transient hyperemic response test (THRT), orthostatic hypotension test (OHT), mean flow index (Mx), and transfer function autoregulation index (TF-ARI). MEDLINE®, BIOSIS, EMBASE, Global Health, Scopus, Cochrane Library (inception to December 2016), and reference lists of relevant articles were searched. A two tier filter of references was conducted. The total number of articles utilizing each of the nine searched techniques for intermittent/semi-intermittent autoregulation techniques in adult TBI were: CTP/Xe-CT (10), PET (6), MRI (0), AVDO2 (10), ARI-based TCDT (9), THRT (6), OHT (3), Mx (17), and TF-ARI (6). The premise behind all of the intermittent techniques is manipulation of systemic blood pressure/blood volume via either chemical (such as vasopressors) or mechanical (such as thigh cuffs or carotid compression) means. Exceptionally, Mx and TF-ARI are based on spontaneous fluctuations of cerebral perfusion pressure (CPP) or mean arterial pressure (MAP). The method for assessing the cerebral circulation during these manipulations varies, with both imaging-based techniques and TCD utilized. Despite the limited literature for intermittent/semi-intermittent techniques in adult TBI (minus Mx), it is important to acknowledge the availability of such tests. They have provided fundamental insight into human autoregulatory capacity, leading to the development of continuous and more commonly applied techniques in the intensive care unit (ICU). Numerous methods of intermittent/semi-intermittent pressure autoregulation assessment in adult TBI exist, including: CTP/Xe-CT, PET, AVDO2 technique, TCDT-based ARI, THRT, OHT, Mx, and TF-ARI. MRI-based techniques in adult TBI are yet to be described, with the main focus of MRI techniques on metabolic-based cerebrovascular reactivity (CVR) and not pressure-based autoregulation.

Ambulatory 24-h ECG monitoring and cardiovascular autonomic assessment for the screening of silent myocardial ischemia in elderly type 2 diabetic hypertensive patients.

The aim of the study was to evaluate the usefulness of Holter monitoring for the detection of silent myocardial ischemia (SMI) in elderly type 2 diabetic patients with hypertension and the possible relationship between SMI and cardiovascular autonomic neuropathy (CAN). Two hundred and forty-three asymptomatic outpatients, aged 65-75years, with type 2 diabetes and essential hypertension underwent 24-h ECG monitoring and 5 tests for the evaluation of both parasympathetic (heart rate variability, response to breath deeping, and Valsalva manoeuvre) and sympathetic (cold pressor test and orthostatic hypotension test) autonomic function. A total of 518 asymptomatic episodes of ST depression during Holter monitoring indicative of SMI were detected in 51 of the 243 studied patients (20.9%). None of the patients with ST depression episodes exhibited a normal response to at least one of the evaluated autonomic function tests, whereas 22 of the 192 patients without ST changes (11.4%) exhibited a normal response to all tests. Abnormality in both parasympathetic and sympathetic function test responses was found in 94.1% of patients with ST depression episodes vs 26.1% of those without ST changes (P<0.001). Statistical evaluation of the relationship between the abnormal response to single autonomic function test and episodes of ST depression was highly significant for all the 5 tests (P<0.001). These results indicate that: (a) Holter monitoring enables to detect ST segment changes indicative of SMI in 20.9% of elderly diabetic patients with hypertension; (b) the presence of autonomic cardiac dysfunction in these patients suggests a role of diabetic neuropathy in the pathogenesis of SMI; and

Age Related Changes in Autonomic Functions.

Autonomic Nervous System (ANS) imbalance may trigger or enhance pathology in different organ systems that varies in different age groups hence objective of present study was to evaluate association of different Age-groups with autonomic functions. A cross-sectional study was conducted in 62 healthy volunteers in Department of Physiology LLRM Medical College Meerut, India. Volunteers were divided into three groups as younger (15-45 years), middle (45-60) and elder age (above 60), Autonomic functions were tested in three domains viz. Cardio-vagal, adrenergic and sudomotor functions. Numerical data was summarized as mean and standard deviation and categorical data as count and percentage. ANOVA and Chi-square test were used to find difference among groups, p<0.05 was considered statistically significant. Mean ± standard deviation OHT(Orthostatic Hypotension Test) among of younger, middle and elder age groups were 8.80±2.28, 13.40±4.64 and 21.82±6.04 respectively which represent decrease in sympathetic functions with age (p<0.001). Cardio-vagal or parasympathetic responses indicated by DBT (Deep Breathing Test) Valsalva and 30:15 ratio of HR response to standing tests has shown statistically significant (p<0.001) decrease in mean response with increasing age. Sudomotor response appeared normal in younger and middle group but was interrupted in more than half of elderly people (p<0.001). Sympathetic responses & para-sympathetic responses have shown the significant decline with increasing age group. Sudomotor responses were partially interrupted in elderly age group.

Dysautonomie et troubles urinaires au cours de la sclérose en plaques. Étude clinique, urodynamique et cardiovasculaire

To assess symptoms related to autonomic nervous system alteration in a population of patients suffering from multiple sclerosis (MS) and presenting with urinary symptoms. We investigated 65 patients (mean age 47.5 years) suffering from MS, and presenting with urological dysfunction by means of symptom scores, urodynamic investigation, cardiovascular autonomic function tests (orthostatic hypotension testing, Valsalva test, deep breath test, cold pressor test) and sympathetic skin responses. Forty-five (69%) patients suffered from overactive bladder, 48 (73%) from voiding dysfunction, 14 (21%) from urinary retention and 13 (20%) from fecal incontinence. Urodynamic investigation demonstrated overactive detrusor in 46 (70%) cases, and underactive detrusor in four (6%) cases. Twenty-five (38%) patients had dysautonomia without correlation neither with clinical or urodynamic data, nor gravity of multiple sclerosis (EDSS). In this series, the prevalence of dysautonomia was high in patients suffering from MS and presenting with urinary disorders.

A Comparative Study of Cardiovascular Autonomic Function Tests in Yoga Practitioners and Controls

Background: In the present age, a great emphasis is being laid on the practice of yogic postures as a form of highly effective physical exercise for keeping the body healthy and also for the control of disease process. Rhythmic breathing controls the mind, lungs and heart which are located in the thoracic cage and are under the control of autonomic nervous system. The aim of this study was to evaluate the cardiovascular autonomic function tests among yoga practitioners. Method: 75 healthy volunteers (aged 18-31 years)were divided in to three groups; the first two yoga groups ( each group ,n=25 ) consisted of subjects who were practicing the yoga (pranayama and suryanamaskarams) for less than 2 years and more than 2 years, respectively and the third group was controls (n=25). Autonomic function tests were performed for both sympathetic and parasympathetic activity ,which include deep breathing test, valsalva maneuver, heart rate response to standing posture (30:15 ratio) , orthostatic hypotension test and sustained hand grip test. Results: The statistics showed a significant value for heart rate variability , 30:15 ratio ,hand grip test, othrostatic hypotension test and valsalva ratio in group 1 and 2 yoga practitioners (p<0.05) than in controls. But no significant difference observed in terms of resting heart rate in all groups. The overall ewing's autonomic dysfunction score was high in controls compared to yoga practicing subjects ((p<0.05). Conclusion: It is evident that yoga develops an ability to control cardiovascular autonomic functions and would prepare the body to overcome stress by modulating and optimizing sympathetic activities.

Plantar thermography is useful in the early diagnosis of diabetic neuropathy

OBJECTIVES:This study evaluated plantar thermography sensitivity and specificity in diagnosing diabetic polyneuropathy using cardiac tests (heart rate variability) as a reference standard because autonomic small fibers are affected first by this disease.METHODS:Seventy-nine individuals between the ages of 19 and 79 years old (28 males) were evaluated and divided into three groups: control (n = 37), pre-diabetics (n = 13) and type 2 diabetics (n = 29). The plantar images were recorded at baseline and then minutes after a provocative maneuver (Cold Stress Test) using an infrared camera that is appropriate for clinical use. Two thermographic variables were studied: the thermal recovery index and the interdigital anisothermal technique. Heart rate variability was measured in a seven-test battery that included three spectral indexes (in the frequency domain) and four Ewing tests (the Valsalva maneuver, the orthostatic test, a deep breathing test, and the orthostatic hypotension test). Other classically recommended tests were applied, including electromyography (EMG), Michigan inventory, and a clinical interview that included a neurological physical examination.RESULTS:Among the diabetic patients, the interdigital anisothermal technique alone performed better than the thermal recovery index alone, with a better sensitivity (81.3%) and specificity (46.2%). For the pre-diabetic patients, the three tests performed equally well. None of the control subjects displayed abnormal interdigital anisothermal readouts or thermal recovery indices, which precluded the sensitivity estimation in this sample of subjects. However, the specificity (70.6%) was higher in this group.CONCLUSION:In this study, plantar thermography, which predominately considers the small and autonomic fibers that are commonly associated with a sub-clinical condition, proved useful in diagnosing diabetic neuropathy early. The interdigital anisothermal test, when used alone, performed best.

Disturbances of QT interval in patients with diabetic autonomic neuropathy

Introduction. Autonomic neuropathy in diabetes, being insufficiently clinically defined, is related to numerous clinical syndromes. The aim of the study was to establish the relationships between autonomic neuropathy in diabetes and QT interval disturbances in our diabetic patients group, as well as the sensitivity of certain cardiovascular tests in detection of pathologic QT dispersion. Method. 100 diabetic patients, among whom there were equal numbers of patients with type 1 and type 2 diabetes, as well as 20 healthy persons in the control group, were included in the study. Ewing cardiovascular tests were used for diagnosis of autonomic neuropathy in diabetes. In standard 12-lead ECG, QTc mean, QTc maximal, QTc minimal and QTc dispersion (difference between QTc maximal and QTc minimal) were determined. QTc dispersion higher than 43 mS was considered abnormal. Methods of descriptive statistics and hypothesis testing were used to process the data Results. There was a positive correlation between autonomic neuropathy in diabetes and QTc maximal, QTc mean and QTc dispersion. No correlation was observed between QTc dispersion and the tests assessing parasympathetic part of the autonomous nervous system. On the other hand, there was a certain relation between pathologic QT dispersion and orthostatic hypotension test. Conclusion. The tests used in this study, due to their simplicity and reliability, could be utilized in detecting patients with pathologic values of QTc dispersion within the clinical practice settings.

Cardiac sympathetic denervation precedes nigrostriatal loss in the E46K mutation of the α-synuclein gene (SNCA)

Here we report the case of an asymptomatic carrier of the E46K substitution in alpha-synuclein gene where we have documented that cardiac sympathetic denervation precedes nigrostriatal dopaminergic loss. She has been followed up regularly with standard neurological examination, UPDRS, neuropsychological formal testing, parkinson disease sleep scale-PDSS, Epworth scale, Hamilton-D scale, SCOPA Aut, orthostatic hypotension test, brief smell identification test, polysomnography, cerebral 123-I-FP-CIT SPECT, and, 123I-MIBG cardiac scintigraphy. She shows no presence of orthostatic hypotension. Olfactory test results demonstrate normal limits. In the PSG the nocturnal sleep shows mild abnormalities although the sleep efficiency and stage proportion remain under normal limits. The 123-I-FP-CIT SPECT is normal; in contrast, the 123I-MIBG cardiac scintigraphy shows a complete lack of isotopic uptake compatible with a severe sympathetic myocardial denervation. This example of monogenic autosomal dominant parkinsonism due to an alpha-synuclein mutation favours the hypothesis that peripheral autonomous nervous system involvement occurs earlier than the CNS degeneration.

Reappraisal of the diagnostic role of orthostatic hypotension in diabetes

Given the controversial aspects of orthostatic hypotension (OH) testing in diabetes, we evaluated the diagnostic role for cardiac autonomic neuropathy (CAN) and for nondipping of OH, defined according to a fall in systolic blood pressure (BP) > or = 30 (30-OH) or > or = 20 mmHg (20-OH). 164 diabetic patients underwent 24 hours BP monitoring, three heart rate cardiovascular tests, and OH test. Compared to 30 mmHg, the 20 mmHg criterion increased the frequency of OH from 11 to 19.5%. Both 30-OH and 20-OH were associated with CAN (chi (2) = 30.5, P < 0.0001, and chi (2) = 45.1, P < 0.0001, respectively) and nondipping (chi (2) = 31.7, P < 0.0001, and chi (2) = 17.2, P = 0.0001, respectively). ROC curve for orthostatic systolic BP fall provided an AUC of 0.79 +/- 0.04 (95% CI 0.70-0.86) for diagnosing CAN and of 0.77 +/- 0.05 (95% CI 0.66-0.86) for diagnosing nondipping. Both 30-OH and 20-OH showed a low sensitivity and high specificity for CAN [sensitivity 31%, specificity 98%, Likelihood Ratio for a positive result (LR(+)) 17.1; and sensitivity 50%, specificity 95%, LR(+) 9.3, respectively], and for nondipping (sensitivity 40%, specificity 96%, LR(+) 8.9, and sensitivity 47%, specificity 87%, LR(+) 3.5, respectively), having 30-OH a higher LR(+) in both cases. OH had only moderate diagnostic accuracy, with high specificity and low sensitivity, for CAN, diagnosed on the basis of heart rate cardiovascular tests, and-as a novel finding-also for nondipping. A different definition of OH did not substantially affect its diagnostic characteristics, with just a slightly greater ability of the 30 mmHg criterion to estimate the probability of CAN and nondipping.

Usefulness of 24-h Holter monitoring in patients with unexplained syncope and a high likelihood of arrhythmias

Aims: To analyze the diagnostic yield of 24-h electrocardiographic monitoring (Holter) as a function of cardiac disease and electrocardiography (ECG) status in patients with unexplained syncope. Methods: Patients were considered as having unexplained syncope when a careful clinical history, physical and neurological examination, 12-lead ECG and testing for orthostatic hypotension were negative. All patients underwent 24-h Holter. According to the type of arrhythmias that occurred during monitoring, Holter was classified as: (1) normal, in the absence of significant arrhythmias; (2) abnormal, in the presence of significant (e.g. atrial fibrillation) but non-diagnostic arrhythmias; or (3) diagnostic, in the presence of serious arrhythmia (e.g. complete AV block) with simultaneous symptoms. Clinical features, ECG and echocardiography were used to stratify patients and identify those in whom electrophysiological studies (EPS) were indicated. Results: 140 consecutive patients with unexplained syncope underwent 24-h Holter and 44 of them (31%) had non-diagnostic arrhythmias. These occurred more frequently in patients with a positive cardiac history or an abnormal ECG (31/73, 42%), compared to patients without these features (13/67, 19%, p<0.05). Nine of the 140 patients (6%) had serious arrhythmias during Holter considered as diagnostic because of the presence of simultaneous symptoms. These occurred exclusively in patients with a positive cardiac history or an abnormal ECG (9/67, 12%). All diagnostic arrhythmias recorded during Holter occurred in patients in whom EPS was beforehand deemed indicated based on the presence of structural heart disease and/or an abnormal ECG. Conclusions: When restricted to high-risk patients, 24-h Holter remained a useful initial step in the evaluation of unexplained syncope with a symptoms and arrhythmias correlation occurring in 12% of patients. When performed first, this procedure might avoid doing EPS.

Usefulness of 24-h Holter monitoring in patients with unexplained syncope and a high likelihood of arrhythmias

Aims: To analyze the diagnostic yield of 24-h electrocardiographic monitoring (Holter) as a function of cardiac disease and electrocardiography (ECG) status in patients with unexplained syncope. Methods: Patients were considered as having unexplained syncope when a careful clinical history, physical and neurological examination, 12-lead ECG and testing for orthostatic hypotension were negative. All patients underwent 24-h Holter. According to the type of arrhythmias that occurred during monitoring, Holter was classified as: (1) normal, in the absence of significant arrhythmias; (2) abnormal, in the presence of significant (e.g. atrial fibrillation) but non-diagnostic arrhythmias; or (3) diagnostic, in the presence of serious arrhythmia (e.g. complete AV block) with simultaneous symptoms. Clinical features, ECG and echocardiography were used to stratify patients and identify those in whom electrophysiological studies (EPS) were indicated. Results: 140 consecutive patients with unexplained syncope underwent 24-h Holter and 44 of them (31%) had non-diagnostic arrhythmias. These occurred more frequently in patients with a positive cardiac history or an abnormal ECG (31/73, 42%), compared to patients without these features (13/67, 19%, p<0.05). Nine of the 140 patients (6%) had serious arrhythmias during Holter considered as diagnostic because of the presence of simultaneous symptoms. These occurred exclusively in patients with a positive cardiac history or an abnormal ECG (9/67, 12%). All diagnostic arrhythmias recorded during Holter occurred in patients in whom EPS was beforehand deemed indicated based on the presence of structural heart disease and/or an abnormal ECG. Conclusions: When restricted to high-risk patients, 24-h Holter remained a useful initial step in the evaluation of unexplained syncope with a symptoms and arrhythmias correlation occurring in 12% of patients. When performed first, this procedure might avoid doing EPS.

Echocardiography was useful in evaluating unexplained syncope

(2002) Heart 88, 36. Sarasin FP, Junod AF, Carballo D, et al. . Role of echocardiography in the evaluation of syncope: a prospective study. . ; . : . –37....

Review of orthostatic tests on the safety of tamsulosin, a selective alpha1A-adrenergic receptor antagonist, shows lack of orthostatic hypotensive effects.

Two phase III studies with tamsulosin, a selective alpha1A-adrenergic receptor antagonist, were conducted to evaluate the safety and efficacy of the standard treatment doses of 0.4 mg/day and 0.8 mg/day in patients with symptoms of benign prostatic hyperplasia (BPH). These large-scale clinical trials were the first to include extensive testing for possible drug-induced orthostatic hypotension (OH). The frequency of positive orthostatic tests and magnitude of vital sign changes were compared among tamsulosin and placebo-treated groups. The results indicate that tamsulosin up to 0.8 mg/day does not induce higher risk of OH than that of placebo. Data from post-marketing surveillance (PMS) studies of tamsulosin indicate that the incidence of hypotension and syncope is extremely low in community-dwelling elderly men treated for BPH. From the results of the phase III studies, PMS studies and an active-controlled clinical pharmacology study, we conclude that the orthostatic test is a useful and convenient method to evaluate the risk of OH and syncope during the investigational stage.

Autonomic dysfunction in multiple sclerosis: cervical spinal cord atrophy correlates.

Autonomic dysfunction has rarely been studied in patients suffering from multiple sclerosis (MS). Some hypotheses have concerned the pathophysiology, especially with regard to a possible spinal cord origin. However, there have been no previous studies on autonomic dysfunction in MS and spinal cord lesions. This study assessed the frequency of autonomic dysfunction (AD) in MS and the correlation to spinal cord magnetic resonance imaging (MRI) findings. We prospectively studied 75 MS patients (25 with relapsing-remitting forms, 25 with secondary progressive forms and 25 with primary progressive forms). We performed sympathetic skin response, R-R interval variability and orthostatic hypotension testing. Spinal cord MRI was performed to detect demyelinating lesions (sagittal and axial plane) or spinal cord atrophy. Clinical and laboratory evidence of AD was found in 84% and 56% of MS patients, respectively. The correlation of the latter with disability was evaluated using the Extended Disability Status Scale. AD was more frequent in primary progressive MS than in the other two forms. AD was correlated with spinal cord cross-sectional area reduction but not with spinal cord hyperintensities. This study confirms that the frequency of AD in MS, especially in primary progressive forms, has until now been underestimated. Furthermore, AD appears to be more closely related to axonal loss, as demonstrated by spinal cord atrophy, than to demyelinating lesions.