番茄社区

People with postural orthostatic tachycardia syndrome (POTS) found some relief wearing a waist-high compression garment, according to a small 30-person trial with randomized crossover design.

On the 10-minute head-up tilt test (HUT), larger areas of compression around the torso were associated with significant downward trends in heart rate (HR) and Vanderbilt Orthostatic Symptom Score (VOSS) symptoms:

• No compression: HR 109 beats/min on average, with mean VOSS ~25 units
• Lower leg compression: 103 beats/min, and VOSS ~23 units
• Abdominal and thigh compression: 97 beats/min, with VOSS ~15 units
• Full abdominal and leg compression: 92 beats/min, and VOSS ~10 units

The study therefore provides "proof-of-principle evidence to support the acute efficacy of this relatively inexpensive and easy to implement treatment" for people with POTS, according to Satish Raj, MD, of University of Calgary in Alberta, and colleagues reporting in the Jan. 26 issue of the .

When surveyed, 56% of study participants said they felt a lot better with full compression compared with zero compression, and another 22% said they felt a little better.

Effects of compression seemed to be driven by improved maintenance of stroke volume with compression during HUT. Abdominal and thigh compression and full compression both kept stroke volume and systolic blood pressure (BP) more stable than the lower leg and no compression conditions, the authors reported.

Compression garments are frequently prescribed off-label for POTS patients despite the limited evidence base supporting their effectiveness. External compression is thought to shift the blood pooled in the abdomen and lower extremities back to the central circulation, increasing pre-load and reducing HR, Raj and colleagues explained.

Although there were greater benefits with more compression in the study, abdominal compression alone may be of clinical benefit to patients, they noted.

"Some patients may not tolerate FULL compression due to varying circumstances, including physical discomfort and heat, in which case, ABDO [abdominal and thigh]-only lower body compression options may help to mitigate some of the challenges associated with regular compression garment use while still providing some HR and symptom reduction," they wrote.

POTS is a chronic form of with no approved medications. Patients experience a a sustained HR increase of ≥30 beats/min within 10 minutes of upright posture from a supine position (with no BP decrease of 20/10 mm Hg) on top of their orthostatic symptoms (e.g., light-headedness, palpitations, nausea).

Yet the question of what POTS actually is is the subject of debate, according to an by David Benditt, MD, of University of Minnesota Medical School in Minneapolis, and Richard Sutton, DSc, MBBS, of Imperial College Healthcare and Hammersmith Hospital in London.

"Initially, patients with POTS consisted of a select group of young individuals (predominantly female) in whom excessive tachycardia accompanying movement to upright posture was relieved by recumbence. For many clinicians, the latter observations seem no longer to be critical for diagnosing POTS," the editorialists wrote.

People with POTS also experience symptoms that are unrelated to upright posture, such as chronic fatigue and migraine, they noted. "Inevitably then, as the range of symptoms incorporated into the POTS concept increases, the orthostatic connection becomes increasingly tenuous."

The first step to diagnosing POTS should be eliminating other potentially treatable causes of a person's POTS-like condition, Benditt and Sutton noted.

Thus, the HUT-induced HR change in the study provides "helpful insight into vascular targets for compression therapy in POTS. However, its use as a surrogate for overall symptomatic benefit must be viewed cautiously because in current conventional usage patients with POTS present a wide range of largely nonposture-related symptoms," the pair warned.

For their study, Raj and colleagues included 30 patients with physician-diagnosed POTS, 28 of whom were women. Average age was 32 years, and BMI averaged 24 kg/m².

Participants tested each of four compression conditions in random order by performing 10-minute HUTs on a tilt table with 10-minute breaks in supine position in between. Continuous HR and BP measurements were taken throughout the study.

The compression garment tested came in a noninflatable series of neoprene wraps with Velcro straps. It applied approximately 20- to 40-mm Hg compression in adjustable arrangements across the body.

Measured effects of the compression garment could have been blunted in the study, according to Raj's group; patients had been asked to hold medications on the morning of their HUT, but some were unable to comply.

Other limitations of the study include a primarily female study population and the lack of of blinding among participants.

"Further studies evaluating the benefits of commercially available compression garments, including in an outpatient setting and over longer durations, as well as qualitative studies to understand the effects of (and tolerance of) these garments by patients with POTS are required," Raj's team said.

Comment