Postural orthostatic tachycardia syndrome associated with multiple sclerosis.

The aim of this study was to determine if there is a difference in the frequency of postural orthostatic tachycardia syndrome (POTS) in patients with multiple sclerosis (MS) compared to patients with symptoms of orthostatic intolerance and with no evidence of MS or other neurological illness. We analyzed data gathered from 293 patients who underwent the head-up tilt table test protocol. Group 1 included prospectively analyzed 112 with MS and group 2 included retrospectively analyzed 181 patients who were evaluated because of symptoms of orthostatic intolerance, and with no evidence of MS or other neurological illness. If POTS was identified the head-up tilt table test was repeated and supine as well as standing serum epinephrine and norepinephrine were determined. POTS was identified in 39 patients: 21 (19%) in the MS group comparing to 18 (10%) in the non MS group (p=0.035). There was no difference between groups in the occurrence of POTS associated syncope (p=0.52). There was no difference between groups in the epinephrine or norepinephrine in supine and standing positions. While both standing epinephrine and norepinephrine levels were significantly higher compared to levels in the supine position in the non MS group, only standing norepinephrine levels were significantly higher in the MS group. The results of this study suggest that POTS is associated with MS.

Adamec I ，Lovrić M ，Žaper D ，Barušić AK ，Bach I ，Junaković A ，Mišmaš A ，Habek M ... -  《-》

Neurocardiogenic syncope coexisting with postural orthostatic tachycardia syndrome in patients suffering from orthostatic intolerance: a combined form of autonomic dysfunction.

There is anecdotal evidence that one or more forms of orthostatic intolerance (OI) subgroups may coexist in the same patients. However, there is a paucity of published data on the clinical features and management of patients who suffer from coexisting features of postural tachycardia syndrome (POTS) and neurocardiogenic syncope (NCS). We herein present our experience of 18 patients who we found displayed evidence of coexisting NCS and POTS. We reviewed charts of 300 POTS patients seen at the University of Toledo Syncope and Autonomic Disorders Center from 2003 to 2010 and found 18 patients eligible for inclusion in this study. Patients were included in this study if they reported clinical symptoms consistent with both POTS and NCS and then demonstrated a typical POTS pattern (a rise in heart rate without change in blood pressure [BP]) on head up tilt table (HUTT) within the first 10 minutes of upright posture followed by a neurocardiogenic pattern (a sudden fall in heart rate and/or fall in blood pressure) reproducing symptoms that were similar to the patients spontaneous episodes. We found 18 patients, mean age (30 ± 12), with 15 (84%) women and three (16%) men, who met the inclusion criterion for this study. Each of these 18 patients demonstrated a typical POTS pattern within the first 10 minutes on initial physical exam and on a HUTT. Continued tilting beyond 10 minutes resulted in a sudden decline in heart rate (which in some patients manifested as an asystole that lasted anywhere between 10 and 32 seconds [mean of 18 seconds]) and/or a fall in BP in each of these patients demonstrating a pattern consistent with neurocardiogenic subtype of OI. The mean time to the NCS pattern of a fall in BP and heart was 15 minutes with a range of 13-20 minutes. This group of patients was highly symptomatic and reported frequent clinical symptoms that were suggestive of OI. Recurrent presyncope, syncope, orthostatic palpitations, exercise intolerance, and fatigue were the principal symptoms reported. NCS may coexist with POTS in a subgroup of patients suffering from OI.

Kanjwal K ，Sheikh M ，Karabin B ，Kanjwal Y ，Grubb BP ... -  《-》

Use of octreotide in the treatment of refractory orthostatic intolerance.

Kanjwal K ，Saeed B ，Karabin B ，Kanjwal Y ，Grubb BP ... -  《-》

Distinct neurohumoral biomarker profiles in children with hemodynamically defined orthostatic intolerance may predict treatment options.

Studies of adults with orthostatic intolerance (OI) have revealed altered neurohumoral responses to orthostasis, which provide mechanistic insights into the dysregulation of blood pressure control. Similar studies in children with OI providing a thorough neurohumoral profile are lacking. The objective of the present study was to determine the cardiovascular and neurohumoral profile in adolescent subjects presenting with OI. Subjects at 10-18 yr of age were prospectively recruited if they exhibited two or more traditional OI symptoms and were referred for head-up tilt (HUT) testing. Circulating catecholamines, vasopressin, aldosterone, renin, and angiotensins were measured in the supine position and after 15 min of 70° tilt. Heart rate and blood pressure were continuously measured. Of the 48 patients, 30 patients had an abnormal tilt. Subjects with an abnormal tilt had lower systolic, diastolic, and mean arterial blood pressures during tilt, significantly higher levels of vasopressin during HUT, and relatively higher catecholamines and ANG II during HUT than subjects with a normal tilt. Distinct neurohumoral profiles were observed when OI subjects were placed into the following groups defined by the hemodynamic response: postural orthostatic tachycardia syndrome (POTS), orthostatic hypotension (OH), syncope, and POTS/syncope. Key characteristics included higher HUT-induced norepinephrine in POTS subjects, higher vasopressin in OH and syncope subjects, and higher supine and HUT aldosterone in OH subjects. In conclusion, children with OI and an abnormal response to tilt exhibit distinct neurohumoral profiles associated with the type of the hemodynamic response during orthostatic challenge. Elevated arginine vasopressin levels in syncope and OH groups are likely an exaggerated response to decreased blood flow not compensated by higher norepinephrine levels, as observed in POTS subjects. These different compensatory mechanisms support the role of measuring neurohumoral profiles toward the goal of selecting more focused and mechanistic-based treatment options for pediatric patients with OI.

Wagoner AL ，Shaltout HA ，Fortunato JE ，Diz DI ... -  《-》

Autonomic dysfunction presenting as postural orthostatic tachycardia syndrome in patients with multiple sclerosis.

Kanjwal K ，Karabin B ，Kanjwal Y ，Grubb BP ... -  《International Journal of Medical Sciences》