Orthostatic Disorders Research Articles

Characteristics and Presentation of Orthostatic Hypertension in Community-Dwelling Older Adults

Abstract Background Standing poses a hemodynamic challenge for the cardiovascular system, regulated by neurohumoral reflexes. In 2023, an elevated blood pressure response upon standing was officially defined as a minimum 20 mmHg increase in systolic pressure during position changes, distinguishing Orthostatic Hypertension (OHT) as a condition where blood pressure exceeds 140 mmHg when standing. This new definition underscores the importance of understanding the implications of OHT on individuals' health and quality of life. Methods Retrospective study of the Technology Research for Independent Living (TRIL) Clinic at St. James’s Hospital, from August 2007 to May 2009. The population included healthy community-dwelling adults aged 60 and older. This study aimed to profile individuals with OHT, understand the predictors of this condition, and explore its association with biopsychosocial variables. Results In a study of 442 participants (67.7% female, mean age 72.7), we identified a prevalence rate of 12.9% for an exaggerated orthostatic pressor response and observed OHT in 6.1% of participants at the 120-second mark after standing. Additionally, significant associations were discovered between OHT and conditions such as heart failure, stroke, and the use of certain medications such as SSRI and ACE inhibitors. Conclusion The results of this study highlight the potential health consequences of OHT among older adults, particularly in those with pre-existing cardiovascular conditions. Further research is needed to explore this lesser-known but significant orthostatic disorder.

Differences in Heart Rate Variability in the Frequency Domain between Different Groups of Patients.

Background and Objectives: Heart rate variability (HRV) is defined as a physiological variation in duration between sinus beats. The aim of this study was to research and analyze the HRV between various groups of patients. Materials and Methods: A retrospective study was conducted in an outpatient setting. Patients who had undergone a tilt-table test were selected for this study and were divided into three groups based on their self-reported health anamnesis: group 1 (n = 84, mean age 45.8 ± 17.8) consisted of patients with no known orthostatic intolerance or neurodegenerative disease, group 2 consisted of patients with a known or suspected orthostatic intolerance (n = 50, mean age 46.5 ± 18.6), and group 3 consisted of patients with a known or suspected neurodegenerative disorder (n = 29, mean age 55.6 ± 20.4). During the tilt-table test, HRV frequency-domain parameters-normalized low frequency (LFnu) and high frequency (HFnu), absolute powers-absolute low frequency (LF-RRI), absolute high frequency (HF-RRI), and LF/HF ratio-were recorded during 5 min rest in the supine position. Results: Group 1 had a reduced LFnu at 52.93% (SD: 18.00) compared to group 2 at 58.57% (18.06) and group 3 at 61.80% (SD: 17.74), and group 1 had increased HFnu: group 1-47.08% (SD: 17.97), group 2-41.41% (SD: 18.03), and group 3-38.16% (SD: 14.7). LFnu and HFnu differences were statistically significant (p < 0.05). LF-RRI was reported as follows: group 1-531.32 ms2 (SD: 578.57), group 2-346.2 ms2 (SD: 447.96), and group 3-143.21 ms2 (SD: 166.96). HF-RRI was reported as follows: group 1-835.87 ms2 (SD: 1625.42), group 2-297.46 ms2 (SD: 507.15), and group 3-70.83 ms2 (SD: 75.67). LF-RRI and HF-RRI comparisons between groups were statistically significant (p < 0.001). LF/HF ratios were reported as follows: group 1-1.91 (SD: 2.29), group 2-2.43 (SD: 2.33), and group 3-2.54 (SD: 2.17). LF/HF ratio comparisons between groups were statistically significant at p < 0.05. Conclusions: This study shows that patients with known or suspected orthostatic intolerance and neurodegenerative disorders have reduced HRV, possibly caused by reduced parasympathetic modulation. HRV in patients with known or suspected neurodegenerative disorders is reduced more severely than in patients with orthostatic disorders. Other studies in HRV have indicated a possible increase of risk in cardiovascular disorders in patients with reduced HRV, and therefore, HRV analysis could be a potential clinical diagnostic tool. However, the lack of universally agreed upon methodology, reference values, and possible external and internal factor influence hinders the introduction of HRV examinations into wider clinical practice.

ВЛИЯНИЕ СЕРИИ ВРАЩЕНИЙ НА ЦЕНТРИФУГЕ КОРОТКОГО РАДИУСА НА АНТИОРТОСТАТИЧЕСКИЕ РЕАКЦИИ АРТЕРИАЛЬНОЙ ГЕМОДИНАМИКИ ЗДОРОВЫХ ЛИЦ (ПО ДАННЫМ ДОПЛЕРФЛОУМЕТРИИ)

Methodology of using a short-arm centrifuge (SAC) as a countermeasure and/or correction of orthostatic disorders will rely on the experimental evidence of the effects produced by various SAC protocols on the antiorthostatic reactions of hemodynamics. The ultimate purpose of the investigations is to develop artificial gravity (AG) protocols for orbital SAC primarily, and also for the needs of healthcare services. The paper presents the results of laser Doppler flowmetry (LDF) in a series of 5 SAC rotations (+Gz) with a modified (shortened) protocol. Reduction of rotation to 45 min (vs 60 min in the session of 2022) was favorable to the general tolerance and did not reduce effectiveness. It was established that a series of 5 rotations with gradual duration reduction and alternating g-values (+1.27 and +2.06 Gz) had a stimulating effect on the antiorthostatic reactions of peripheral arterial hemodynamics. This fact was confirmed by comparison of the records during rotations 1 and 5, and the results of passive postural tests as a control. Conceivably, in future it will be necessary to develop a variety of protocols to meet other specific tasks.

Patients with POTS fear that data on abnormal haemodynamic physiology have been ignored

Norcliffe-Kaufmann et al.1 recently reported that patients with postural orthostatic tachycardia syndrome (POTS) had an exaggerated anticipatory heart rate (HR) increase in the 30 s prior to head-up tilt (HUT). Based largely on these findings, the authors conclude that patients with POTS suffer from a ‘fear-conditioning behavioural response’ to the thought of standing, and that POTS is a ‘functional psychogenic disorder’ that would best be treated by mental health professionals. Their basic finding is of potential interest; unfortunately their conclusions ignore limitations in their participant selection, methodological approach, and prior research into POTS pathophysiology, and they illustrate their lack of knowledge of psychiatric diagnosis and care. A major study limitation is the choice to compare POTS patients with a healthy control group. In a previous report,2 participants with POTS scored higher on the anxiety sensitivity index than healthy control participants, but scores were not significantly different compared to the general population.2 Patients with chronic illness have elevated depression, anxiety and health anxiety scores compared to healthy controls.3 Consequently, Norcliffe-Kaufmann et al.1 should have chosen a control group with chronic illness but without an orthostatic disorder. Without this control group, the study finding of exaggerated anticipatory tachycardia to a tilt stimulus may simply reflect elevated somatic anxiety due to chronic illness.

Detection of Preclinical Orthostatic Disorders in Young African and European Adults Using the Head-Up Tilt Test with a Standardized Hydrostatic Column Height: A Pilot Study

Arterial hypertension (AH) remains the most common disease. One possible way to improve the effectiveness of the primary prevention of AH is to identify and control the preclinical orthostatic disturbances that precede the development of AH. The aim of the study was to determine the feasibility of a new protocol for the head-up tilt test (HUTT) with a standardized hydrostatic column height for the detection of asymptomatic orthostatic circulatory disorders and their racial differences in young African and European adults. Methods. In total, 80 young healthy adults (40 African and 40 European) aged 20–23 years performed the HUTT with a standardized hydrostatic column height of 133 cm. The hemodynamic parameters were recorded using a Task Force Monitor (3040i). The cardio-ankle vascular index (CAVI) was measured using a VaSera VS-2000 volumetric sphygmograph. Results. The baseline and orthostatic hemodynamic changes in both racial groups were within normal limits. Orthostatic circulatory disturbances were not detected in 70% of the European participants and 65% of the African participants; however, preclinical orthostatic hypertension, which precedes AH, was detected using the new HUTT protocol in 32.5% of the African participants and 20% of the European participants. The baseline CAVI was higher in the European group compared to the African group. Conclusion. The results of this study showed the feasibility of the detection of preclinical orthostatic disturbances in young adults and the detection of their racial differences using the HUTT protocol, providing the use of a standard gravity load. Further study on the evolution of preclinical orthostatic disturbances and their relation to increased vascular stiffness is necessary among large samples.

Dietary sodium and health: How much is too much for those with orthostatic disorders?

High dietary salt (NaCl) increases blood pressure (BP) and can adversely impact multiple target organs including the vasculature, heart, kidneys, brain, autonomic nervous system, skin, eyes, and bone. However, patients with orthostatic disorders are told to increase their NaCl intake to help alleviate symptoms. While there is evidence to support the short-term benefits of increasing NaCl intake in these patients, there are few studies assessing the benefits and side effects of long-term high dietary NaCl. The evidence reviewed suggests that high NaCl can adversely impact multiple target organs, often independent of BP. However, few of these studies have been performed in patients with orthostatic disorders. We conclude that the recommendation to increase dietary NaCl in patients with orthostatic disorders should be done with care, keeping in mind the adverse impact on dietary NaCl in people without orthostatic disorders. Modest, rather than robust, increases in NaCl intake may be sufficient to alleviate symptoms but also minimize any long-term negative effects.

Salt: The paradoxical philosopher's stone of autonomic medicine.

Sodium chloride, or common table salt, for millennia has played a prominent role in human affairs. Salt is also a key molecule for regulating intravascular fluid volume in patients with orthostatic disorders. In this first article of a special issue of the journal focusing on salt and the autonomic nervous system, the historical and physiologic significance of salt is reviewed, highlighting its importance to society and to medicine. The relevance of salt both for civilization and for autonomic physiology penetrates into nearly every aspect of life and health. Replacing salt that has been depleted or administering salt to expand intravascular volume is considered standard treatment for patients with orthostatic hypotension and syndromes of orthostatic intolerance. The potential longterm effects of added salt, including effects unrelated to intravascular volume, have been insufficiently studied in patients with autonomic disorders. A salient concern is the potential increased risk of developing hypertension. Underappreciated aspects of salt include its ability to increase anxiety and through nonosmotic mechanisms to contribute to local tissue inflammation. Salt may be either salubrious or detrimental, or possibly both at the same time, depending on the clinical conditions. Reconciling these opposite effects in clinical practice requires weighing benefits against potential risks, assessing what is known alongside what is uncertain, and titrating treatment decisions to the particular needs of each individual patient.

Preclinical predictors of arterial hypertension

Arterial hypertension (AH) remains one of the most common diseases and a leading risk factor for cardiovascular diseases (CVD) in the 21st century. It determines the importance of a search for new factors provoking an increase in blood pressure. This review focuses on studies of preclinical predictors of hypertension. Orthostatic circulatory disorders with clinical signs of cardiovascular deconditioning are risk factors for the development of hypertension and CVD, accompanied by a more rapid increase in vascular stiff ness. Such abnormalities, even minor ones without clinical manifestations, increase the risk of hypertension development in the young population. The review deals with orthostatic changes in hemodynamics and features of neurohormonal change. It has been shown that adaptive processes counteracting an increase in hydrostatic pressure contribute to a significant transient increase in vascular stiff ness. The evolution of orthostatic hemodynamic disorders from preclinical to clinical forms accelerates the process of vascular wall remodeling, leading to a spontaneous increase in its rigidity — one of the significant risk factors for hypertension and CVD. To identify preclinical predictors, a new protocol of passive orthostatic test (POT) was developed. It was standardized not by the tilt angle, but by the height of the hydrostatic column. Further research is needed to evaluate the prognostic capabilities of predictors, to reveal the pathogenetic connection of orthostatic disorders with the development of hypertension, and to remodeling the vascular wall, which causes an increase in its rigidity. It is also required to search for ways to correct preclinical orthostatic disorders in healthy young population for early prevention of hypertension.

Effects of an Innovative Head-Up Tilt Protocol on Blood Pressure and Arterial Stiffness Changes.

The objective of our study was to identify blood pressure (BP) and pulse wave velocity (PWV) changes during orthostatic loading, using a new the head-up tilt test (HUTT), which incorporates the usage of a standardized hydrostatic column height. Methods: 40 healthy subjects 20–32 years performed HUTT, which was standardized to a height of the hydrostatic column at 133 cm. Exposure time was 10 min in each of 3 positions: horizontal supine 1, HUTT, and horizontal supine 2. The individual tilt up angle made it possible to set the standard value of the hydrostatic column. Hemodynamic parameters were recorded beat to beat using “Task Force Monitor 3040 i”, pulse-wave velocity (PWV) was measured with a sphygmograph–sphygmomanometer VaSera VS1500N. Results: Orthostatic loading caused a significant increase in heart rate (HR) and a decrease in stroke volume (SV) (p < 0.05) but no significant reductions in cardiac output, changes in total vascular resistance (TVR), or BP. An analysis of personalized data on systolic blood pressure (SBP) changes in tilt up position as compared to horizontal position (ΔSBP) revealed non-significant changes in this index in 48% of subjects (orthostatic normotension group), in 32% there was a significant decrease in it (orthostatic hypotension group) and in 20% there was a significant increase in it (orthostatic hypertension group). These orthostatic changes were not accompanied by any clinical symptoms and/or syncope. During HUTT, all subjects had in the PWV a significant increase of approximately 27% (p < 0.001). Conclusion: The new test protocol involving HUTT standardized to a height of hydrostatic column at 133 cm causes typical hemodynamics responses during orthostatic loading. Individual analysis of the subjects revealed subclinical orthostatic disorders (OSD) in up to 52% of the test persons. During HUTT, all test subjects showed a significant increase in PWV. The new innovative HUTT protocol can be applied in multi-center studies in healthy subjects to detect preclinical forms of orthostatic disorders under standard gravity load conditions.

ВЛИЯНИЕ 14-СУТОЧНОЙ ОРТОСТАТИЧЕСКОЙ ГИПОКИНЕЗИИ НА ОРТОСТАТИЧЕСКУЮ УСТОЙЧИВОСТЬ ОРГАНИЗМА ЧЕЛОВЕКА

Effect of 14-day head up bedrest (HUBR) on the human orthostatic tolerance studied with participation of 23 essentially healthy male subjects at the age of 18 to 35 years. HUBR with the head-end tilted up at +9.6º was to imitate physiological effects of the lunar gravity. Orthostatic tolerance was tested on the day prior to and immediately after HUBR completion with subjects tilted up to +70° for 20 min maximum. The parameters registered before, during and after the tilt test included blood pressure, ECG and heart rate. In comparison with the baseline testing, HUBR reduced the number of completed tests and increased the number (10 vs. 4) of tests terminated for the reason of precollapse (p &lt; 0.05). The group mean time of OS test tolerance decreased by 3.8 minutes (p &lt; 0.01) and time interval between the test onset and precollapse decreased by 4.7 minutes (p = 0.055). For the most part, orthostatic disorders following HUBR were described as a vasodepressor type hypotension collapse with high activity of the chronotropic function of the heart. Several cases of vagus-mediated HR slowing pointed to a sharp decline of the sympathetic nervous activity which is an important mechanism of hemodynamics regulation in changed postural conditions.

Влияние гипоксических тренировок на ортостатическую устойчивость человека до и после моделированной микрогравитации

Reduced orthostatic tolerance (OT) is a serious concern facing space medicine. This work sought to evaluate the effects of intermittent hypoxic training (IHT) on OT in humans before and after 3 days of head-down bed rest (HDBR) used to model microgravity. The study was carried out in 16 male volunteers aged 18 to 40 years and included 2 series of experiments with 11-day and 21-day IHT administered on a daily basis. During the first IHT session, the concentration of oxygen in the inspired gas mixture was 10%; for other sessions it was adjusted to 9%. OT was assessed by a 20-minute-long orthostatic tilt test (OTT) conducted before and after HDBR. Before HDBR, orthostatic intolerance was observed in 3 participants, while after HDBR, it was observed in 9 of 16 volunteers (p &lt; 0.05). During OTT conducted after HDBR, the heart rate (HR) exceeded control values by 26.8% (p &lt; 0.01). Preexposure to any of the applied IHT regimens led to a reduction in the number of volunteers with orthostatic intolerance. After the 11-day IHT program, there was a less pronounced increase in HR during OTT before HDBR; with the extended IHT regimen, less pronounced changes were observed for HR, systolic, diastolic and mean blood pressure (BP). The increase in HR during OTT after HDBR was significantly lower in the group that had completed the 11-day IHT program, while BP remained stable. The changes in HR and systolic BP were less pronounced in the group that had completed the 21-day IHT program than in the control group (p &lt; 0.05). Thus, IHT reduced the risk of orthostatic disorders and mitigated changes in cardiovascular parameters during the orthostatic test.

Orthostatic circulatory disturbances during verticalization in post-comatose patients after severe brain damages

Objectives: Patients in the post-comatose period after critical brain damages and long-term treatment in intensive care units require special approaches to verticalization due to the risk of orthostatic circulatory disorders and deepening of ischemic processes in the brain.&#x0D; Aim: to study orthostatic disorders occurring during verticalization in patients with and without chronic consciousness disorders, after severe brain damages.&#x0D; Material and methods: 72 patients were examined during the post-comatose period, including 49 (68%) after severe stroke, 17 after severe brain injury, 3 patients with posthypoxic encephalopathy and 3 after brain tumor removal. Non-invasive registration of blood pressure (BP) in the brachial artery and monitoring beat to beat of BP was performed using Drager's bedside monitor complete with a finger sensor. Heart rate monitoring was performed automatically by computer-controlled R to R intervals in real time.&#x0D; The results: Orthostatic circulatory disorders were detected in the majority (19 out of 24) of patients with chronic consciousness impairments and in 12 out of 48 patients who were conscious. The most frequent disorder in group 1 was postural tachycardia syndrome, which was not revealed in patients of group 2. Orthostatic hypotension was observed in 25% of group 1 patients and in 20,8% of group 2 patients. Orthostatic hypertension in both groups did not exceed 10%.&#x0D; Conclusion: orthostatic circulatory disorders were revealed in 19 out of 24 patients in group 1 (79,2%) and in 25% in group 2. Application of the new protocol with real-time monitoring of BP and HR allowed to perform verticalization in all patients without complications. The structure of orthostatic circulatory disorders was established, which should be considered at the beginning of the process of verticalization of patients in the post-comatose period after severe brain damages.

Antioxidants Effect Changes in Systemic Parasympathetic and Sympathetic Nervous System Responses and Improve Outcomes

Parasympathetic and Sympathetic (P&amp;S) imbalance is associated with increased morbidity and mortality risk, including heart failure, coronary artery disease, atrial and ventricular arrhythmias, hypertension and orthostatic disorders, and syncope. Most cardiac medications effect only one or the other of the P&amp;S nervous systems, including: β-blockers, α-blockers, α-agonists, and anti-cholinergics. Non-pharmaceutical treatments also affect the P&amp;S nervous systems; however, nonpharmaceutical treatment is rarely addressed or studied, despite significant evidence-based data demonstrating normalization of Sympathovagal Balance. Fifty consecutive patients from a busy suburban cardiology practice were enrolled in a supplement study. Patients were provided supplements that included 200mg of Alpha-Lipoic Acid (ALA) and 100mg of Co-Enzyme Q10 (CoQ10) which they were instructed to take twice a day, one each with breakfast and dinner. P&amp;S Monitoring (Physio PS, Inc., Atlanta, GA, USA) and Quality of Life (QoL) questionnaires were administered at three month intervals. The combination of supplements, ALA and CoQ10, had a positive effect on the P&amp;S nervous systems as measured directly and also indicated by improvements in BP, HR and reported QoL. The study indicates these supplements help to improve both the resting and challenge P&amp;S responses and resultant physiology. The results suggest antioxidant therapy is a potential complimentary therapy to pharmacological management of patients with poorly controlled BP (i.e., hypertension and possible hypotension) as well as in patients with tachycardia or palpitations. This is a hypothesis generating study of significant importance in an often neglected area of cardiovascular disease in which additional research and studies are needed.

Sensitivity of the Baroreceptors and the State of the Autonomic Nervous System in Patients with Chronic Impairment of Consciousness Due to Severe Brain Damage

Purpose of the study: to examine sensibility of baroreceptors and the autonomic nervous in the passive orthostatic test in patients with chronic impairment of consciousness due to severe brain damage and determine their role in the rehabilitation process.Materials and methods. The study included 30 patients with long-term impairment of consciousness due to severe brain damage (group 1), 10 of them being in the vegetative state (VS) and 20 being in the minimally conscious state (MCS). Craniocerebral trauma was the main cause of severe damage in that group (53% of patients). The comparison group included 24 patients with focal neurological symptoms caused predominantly — 79.2% of cases — by cerebrovascular disorders (group 2). The control group (group 3) consisted of 22 healthy volunteers of a comparable age. All measurements were done with the help of a Task Force Monitor 1030i (CNSystem, Austria) in the course of passive orthostatic test at 0°–30°–60°–0°. Changes in the power of low-frequency (LFS) and highfrequency spectrum (HFS) of heart rate variability and baroreceptors sensibility (BRS) were analyzed. Statistical analysis was carried out using Statistica-10 software. Significance of inter-group differences on unrelated samples was determined by the Mann–Whitney U-test. Differences between groups were considered significant at P 0.05.Results. Maximal background values of BRS were found in the control group. In group 1 and 2 patients, considerable decrease of that index was noted, which was proportional to the brain damage severity. Similar dynamics was observed for the indices of autonomic nervous system sensibility (LFS and HFS). The main trend of orthostatic changes of BRS, LFS, and HFS was characterized by progressive decrease of the indices with increase of the patients’ angle of tilting and their return to the baseline level after the patients were put back into the horizontal position. 4 patients of group 1 (14%) displayed signs of orthostatic disorders upon tilting to 30°: in 3 cases, orthostatic hypotension was observed, and in one case the postural orthostatic tachycardia syndrome (POTS) was diagnosed. Those patients differed by lower BRS and higher sympathetic system activity (LFS) vs. the same indices of other patients in that group.Conclusion. Patients with chronic impairment of consciousness during the post-comatose period after a severe brain damage display a significant decrease of baroreceptors sensibility and autonomic nervous system disorders manifesting in significantly lower activity of the sympathetic and parasympathetic systems. The prominence of such disorders is associated with brain damage severity. Their risk of developing orthostatic hypotension during tilting towards a vertical position is higher in patients who have lower baroreceptors sensibility, and this should be taken into account beginning the process of their verticalization.

Changes in Systemic Hemodynamics in Orthostasis in Patients With Long-Term Impairment of Consciousness

The purpose of the study: to study hemodynamic parameters and the degree of its orthostatic stability during verticalization in patients with long-term impairment of consciousness in post-comatose period of brain damage.Materials and methods. This study included 30 patients with long-term impairment of consciousness caused by severe brain damage (Group 1), 10 of whom were in a vegetative state (VS) and 20 patients had a minimally conscious state (MCS). A severe traumatic brain injury was the most frequent cause of long-term disorders of consciousness (53.3%), other causes were associated with severe disorders of cerebral circulation (13.4%) and following consequences: rupture of cerebral aneurysms (10%), or post-hypoxic brain damage (10%), or removal of brain tumors (13.3%). The second group was comprised of 24 patients with local neurological symptoms after cerebral circulation disorders. The third group included 40 healthy volunteers. Systemic hemodynamic parameters were monitored using a multifunctional monitor TFM 3040i (CNSystem Austria) . Blood pressure (BP), heart rate (HR), stroke volume (SV), cardiac output (CO), and total peripheral resistance (TPR) were measured in real time. The statistical analysis was carried out using the Statistica-10 software package.Results. 26 patients of the first group (86%) demonstrated satisfactory hemodynamic stability in the tilt test at 30° and 60°; 3 patients of this group presented signs of orthostatic hypotension and 1 patient developed postural orthostatic tachycardia syndrome (SPOT) when tilted by 30°. A comparative analysis of hemodynamic parameters in patients of the first and second groups did not demonstrate significant differences, except for significantly higher HR values and lower SV values in the first group. Parameters of systemic hemodynamics in the horizontal position were significantly different in healthy volunteers, and were characterized by higher SV and CO values and lower BP, HR and TPR values as compared to patients of groups 1 and 2.Conclusion. This study demonstrated a hypokinetic type of blood circulation in all patients with brain lesions; it was more severe in patients with long-term impaired consciousness after severe brain damage. The majority of patients in this group presented satisfactory orthostatic hemodynamic stability; different types of orthostatic disorders were found in 14% of cases. A passive orthostatic test (0—30—60°) applied in this study allowed to diagnose orthostatic disorders at a slight tilt up to the onset of clinical symptoms of brain hypoperfusion. This indicates the need for hemodynamic monitoring in the early stages of patients' verticalization.

The gastrointestinal symptoms present in patients with postural tachycardia syndrome: A review of the literature and overview of treatment.

Orthostatic intolerance, including postural tachycardia syndrome, is often associated with gastrointestinal symptoms. In the vast majority of the cases, the gastrointestinal symptoms are not secondary to the orthostatic disorder, but rather just a comorbid condition. This concept is critical, since treatment aimed at the orthostatic condition will not improve the gastrointestinal symptoms. Only when the gastrointestinal symptoms develop in the upright position and improve or resolve in the supine position, they may be related to the orthostatic stress. The most common symptoms associated with orthostatic intolerance include nausea, dyspepsia, bloating and constipation. The majority of subjects do not have gastroparesis. The chapter discusses available treatments of these conditions.

The Utility of Valsalva Maneuver in the Diagnosis of Orthostatic Disorders (P5.121)

The Utility of Valsalva Maneuver in the Diagnosis of Orthostatic Disorders (P5.121)

The utility of Valsalva maneuver in the diagnoses of orthostatic disorders.

The objective of this study was to assess hemodynamic responses and baroreflex sensitivity (BRS) indexes during Valsalva maneuver (VM) and head-up tilt (HUT) testing in orthostatic intolerance (OI). Patients with neurogenic orthostatic hypotension (NOH, n = 26), postural tachycardia syndrome (n = 26) and symptomatic OI (n = 14) were compared with healthy population (control, n = 107) and inappropriate sinus tachycardia (n = 7). Hemodynamic assessment included patterning and quantification with vagal and adrenergic BRS (BRSa/BRSa1). In NOH, cardiovagal systolic blood pressure (SBP) decrements in VM and HUT were correlated (r = 0.660, P < 0.001); a "V" pattern of VM indicated α-BRSa failure. Yet BRSa1 did not reveal changes vs. control (P > 0.05) or was not applicable in 60% of NOH. In symptomatic OI, compared with control, cardiovagal SBP decrements were larger (P < 0.05); higher BRSa1 contradicted higher adrenergic index (Composite Autonomic Severity Score). Overshoot in phase IV dipped below baseline or dropped ≥ 10 mmHg over 8 s in postural tachycardia syndrome ("N" pattern), but by 3 s in inappropriate sinus tachycardia ("M" pattern). Visualization of distinct VM patterns allows primary evaluation of autonomic dysfunction and differentiation of the various forms of OI. BRSa1 evaluation is compromised by pathological SBP patterns. VM patterning is a valuable nonpostural supplement to HUT capable of detecting and differentiating OI.

Circulation : Clinical Summaries

<i>Circulation</i> : Clinical Summaries

Assessment of cardiac rhythm variability in patients with orthostatic disorders against the background of type 2 diabetes mellitus

Assessment of cardiac rhythm variability in patients with orthostatic disorders against the background of type 2 diabetes mellitus