Postural Orthostatic Tachycardia Syndrome (POTS) is a chronic condition characterized by an abnormal increase in heart rate when moving from a sitting or lying position to a standing one. This disorder is a form of dysautonomia, meaning it involves dysfunction of the Autonomic Nervous System (ANS), which regulates involuntary bodily functions like heart rate and blood pressure. Because symptoms like dizziness, lightheadedness, and fatigue are often triggered by upright posture, non-pharmacological interventions are widely recommended to help manage the condition. Compression garments, such as specialty socks and abdominal binders, are among the most frequently suggested tools for mitigating the effects of orthostatic intolerance.
Understanding the Physiology of POTS
The core problem in POTS is the body’s inability to properly manage blood flow against gravity upon standing. When a person stands, gravity naturally causes a shift, or pooling, of about 10 to 15% of the total blood volume into the lower extremities and abdominal area. In a healthy person, the ANS quickly responds by tightening blood vessels and increasing the return of blood to the heart, which maintains stable blood pressure and heart rate.
In individuals with POTS, this process is impaired, leading to excessive venous pooling in the lower body. This pooling reduces the volume of blood returning to the heart, known as cardiac filling, which in turn lowers cardiac output. To compensate for the reduced blood flow reaching the brain and upper body, the heart reflexively speeds up, resulting in the rapid heart rate, or tachycardia, that defines the syndrome. This compensatory effort is what leads to the symptoms of orthostatic intolerance.
How Compression Therapy Counteracts Blood Pooling
Compression therapy is a physical countermeasure against the gravitational forces that cause blood pooling. The garments apply external, graduated pressure to the limbs, which physically squeezes the veins and arteries. This external pressure reduces the capacity of the blood vessels in the lower extremities, effectively decreasing the space available for blood to pool.
By reducing the volume of pooled blood, the pressure promotes the movement of blood upward, which significantly improves venous return to the heart. Increased blood returning to the heart raises cardiac filling, allowing the heart to pump more blood with each beat. This action helps to stabilize blood pressure and reduces the need for the heart to race to compensate, thereby lessening the symptoms of orthostatic intolerance. Research indicates that this external support can reduce the excessive heart rate increase seen upon standing.
Choosing the Optimal Compression Garments
Selecting the correct compression garment involves considering the pressure level and the extent of body coverage. Compression strength is measured in millimeters of mercury (mmHg), and for managing POTS symptoms, levels of 20–30 mmHg or even 30–40 mmHg are recommended. These pressure levels are substantially higher than the light compression used for travel or mild swelling and often require a professional fitting and a prescription.
The length of the garment is also a significant factor, as waist-high compression tights or stockings are generally considered superior to knee-high socks. Blood pooling often occurs not only in the legs but also in the large veins of the abdomen. Specialists often recommend combining leg compression with an abdominal binder or using full-length compression garments that cover the hips and abdomen. For maximum benefit, garments should be put on while still lying down, before standing up in the morning, to prevent initial blood pooling.
Lifestyle Strategies Beyond Compression
Compression garments are one part of a comprehensive management plan for POTS, which also includes adjustments to daily habits. Fluid intake is emphasized, with recommendations often suggesting at least two to three liters of water per day to help increase overall blood volume. This increased fluid intake is paired with a higher consumption of sodium, often ranging from 3 to 10 grams daily, which helps the body retain the extra fluids.
Exercise and Activity Modification
Exercise is considered a component of treatment, though it must be approached strategically. Recumbent exercises, such as rowing, swimming, or using a recumbent bicycle, are often better tolerated because they reduce the effect of gravity and prevent the orthostatic stress triggered by upright activity. Avoiding prolonged standing and taking frequent breaks to sit or lie down can also help reduce symptom severity throughout the day.