Background Resistance training for leg muscles is recommended for patients with postural tachycardia syndrome (POTS). However, no study has characterized the relationships between orthostatic symptoms, heart rate (HR) increase, and the mass of the lower leg muscle in patients with POTS. We sought to determine the relationships between the mass of the lower leg muscle, HR increase during the head-up tilt (HUT) test, and orthostatic symptoms in patients with POTS.
Methods We prospectively enrolled 42 patients with POTS who were older than 16 years. The muscle mass was estimated using bioelectrical impedance analysis. We used the International Physical Activity Questionnaire-Short Form to measure self-reported physical activity. All patients were asked to complete the Korean version of the Orthostatic Grading Scale (KOGS).
Results The HR increased during the HUT test by 38.7±7.88 beats/minutes. Both the HR increase during the HUT test and the total KOGS score were negatively correlated with the total metabolic equivalent of the task. The leg circumference and muscle mass were not correlated with the HR increase during the HUT test or the KOGS score.
Conclusions The leg circumference and muscle mass were not related to orthostatic symptoms in patients with POTS. Cardiac remodeling or blood volume increase may be responsible for improvement in POTS after physical activity.
Orthostatic dizziness is feeling dizzy or lightheaded when standing up. Hemodynamic orthostatic dizziness can be caused by autonomic dysfunction such as orthostatic hypotension or postural tachycardia syndrome. The interpretation of the autonomic function test results in patients with orthostatic dizziness is crucial for diagnosing and managing the underlying condition. The head-up tilt and Valsalva tests are especially important for evaluating adrenergic function in patients with hemodynamic orthostatic dizziness. However, it is important to note that autonomic function tests do not cover the entire diagnostic process, since their findings need to be considered along with the detailed history and physical examination results of the patient because various differential diagnoses exist for orthostatic dizziness. Ensuring appropriate treatment by interpreting the autonomic function test results can help to determine the improvement of and prevents falls from orthostatic dizziness.
Background Orthostatic intolerance (OI) is a common clinical symptom in dizziness clinic. The head-up tilt table test (HUT) is one of the primary clinical examination for evaluating OI. There is no consensus on the optimum method for diagnosis of orthostatic hypotension (OH). Herein, we performed the additional squat combined with blood pressure (BP) monitoring for OI patients with normal HUT.
Methods The study included 32 consecutive patients with orthostatic intolerance for 3 months since April, 2018 (Period I) and 27 patients with orthostatic intolerance for 3 months since April, 2019 (Period II) in dizziness clinic of Chungnam National University Hospital. During Period II, the additional squat combined with BP test was performed for normal HUT results in patients with OI. In squat combined orthostatic BP measurement, the first BP measurement was taken following 3 minutes of rest at the squat position; afterwards the patients were raised upright and the measurement was monitored for 2 minutes, using a continuous beat-to-beat BP monitoring.
Results In this study, there was significant difference in OH diagnosis (p<0.001); 40.6% (13/32) by conventional HUT (Period I) vs. 92.5% (25/33) by conventional HUT and additional squat test for normal HUT (Period II). In patients with normal HUT, the positive OH was 86.7% (13/15) by the additional squat combined BP measurement (Period II).
Conclusions In addition to HUT, squat test combined with BP measurement might be more informative for understanding and diagnosing the OH, particularly in patients with OI and normal HUT in dizziness clinic.
This paper introduces new diagnostic criteria and differential diagnosis of orthostatic dizziness to help clinicians to diagnose hemodynamic orthostatic dizziness. Clinicians need to be able to discriminate hemodynamic orthostatic dizziness from other types of dizziness that are induced or aggravated when standing or walking. Measurements of the orthostatic blood pressure and heart rate are important when screening hemodynamic orthostatic dizziness. Detailed history-taking, a physical examination, and laboratory tests are essential for finding the cause of hemodynamic orthostatic dizziness. The differential diagnosis of hemodynamic orthostatic dizziness is crucial because it can be caused by various autonomic neuropathies.
Citations
Citations to this article as recorded by
Mareo y vértigo ortostático, funcional y cinetosis Liliana F. Invencio-Da-Costa, Carmen Sánchez-Blanco, Raquel Yáñez-González, Hortensia Sánchez-Gómez, Paula Peña-Navarro, Sofía Pacheco-López, Susana Marcos-Alonso, Cristina Nicole Almeida-Ayerve, Luis Cabrera-Pérez, Victoria Díaz-Sánchez Revista ORL.2023; 15(3): e31540. CrossRef
Background Postural tachycardia syndrome (POTS) refers to the presence of orthostatic
intolerance symptoms associated with a heart rate increment of greater than 30 beats/min,
usually up to 120 beats/min, on head-up tilt test. Symptoms related to POTS are usually lightheadedness, palpitations and tremor, but syncope can also occur. The pathophysiology of POTS is heterogeneous and its prognosis is uncertain.
Methods We prospectively evaluated patients who met the criteria for POTS, at baseline and follow-up, using composite autonomic symptom scores and autonomic tests to assess the autonomic function. We compared the clinical and autonomic test results between baseline and follow-up.
Results Sixty-eight patients met the inclusion criteria for POTS and forty-five patients were ultimately followed up for at least 1 year after baseline. The patients were predominantly young females (84%), with a mean age of 21 years. Most patients showed improved orthostatic symptoms and more than a quarter of patients had no longer met the criteria for POTS at follow-up.
Conclusions Most patients had a benign outcome in that they could resume their daily activities without great limitations. Our results demonstrated a relatively favorable prognosis in most patients with POTS.
Citations
Citations to this article as recorded by
Long‐Term POTS Outcomes Survey: Diagnosis, Therapy, and Clinical Outcomes Jeffrey R. Boris, Edward C. Shadiack, Elizabeth M. McCormick, Laura MacMullen, Ibrahim George‐Sankoh, Marni J. Falk Journal of the American Heart Association.2024;[Epub] CrossRef
Amyloidosis is a systemic disorder associated with clonal plasma cell dyscrasia. Nephrotic syndrome, congestive heart failure, autonomic and peripheral neuropathy is often associated features in amyloidosis. Early diagnosis is most important because of different prognosis by stage. The diagnosis can be delayed since symptoms of amyloidosis may vary or nonspecific. We describe a patient of myeloma-associated amyloidosis, who showed orthostatic intolerance as the first symptom of the disease.
Orthostatic intolerance is defined as the development of various symptoms during standing that are relieved by recumbency. Postural tachycardia syndrome (POTS) is another nomenclature of orthostatic intolerance. POTS characterized by a heart rate increase
Postural orthostatic tachycardia syndrome (POTS) is characterized by increased heart rate with preserved blood pressureon orthostatic stress. Many patients with postural orthostatic tachycardia syndrome can be misdiagnosed as neurosis, chronicfatigue or anxiety disorder. We report a patient with POTS who presented chronic dizziness and fatigue. In approaching toa patient with orthostatic or nonspecific chronic dizziness, the postural heart rate as well as blood pressure should be checkednot to miss the diagnosis.