Usefulness of an abnormal cardiovascular response during low-grade head-up tilt test for discriminating adolescents with Chronic Fatigue [Syndrome] from healthy controls

Journal: American Journal of Cardiology. 2007 Apr 1;99(7):997-1001.

Authors and affiliations: Wyller VB, Due R, Saul JP, Amlie JP, Thaulow E. Department of Pediatrics, Rikshospitalet-Radiumhospitalet Medical Centre, Oslo, Norway; Department of Physiology, University of Oslo, Oslo, Norway.

PMID: 17398200

Hemodynamic dysfunction [hemodynamic refers to the forces involved in blood circulation] is documented in Chronic Fatigue Syndrome (CFS). This study was conducted to investigate cardiovascular responses to orthostatic stress [changes in blood pressure and heart rate when the body's position changes from prone to upright] in adolescents with CFS, using a novel procedure for tilt-table testing.

A total of 27 adolescents with CFS and 33 healthy control subjects with equal age and gender distribution underwent 15 minutes of 20 degrees head-up tilt testing. Heart rate, systolic blood pressure (BP), mean BP, diastolic BP, stroke index, total peripheral resistance index, end-diastolic volume index, and acceleration index were continuously and noninvasively recorded.

At rest, patients with CFS had higher total peripheral resistance index values (p <0.01) and lower stroke index and end-diastolic volume index values (p <0.05) than controls. During 20 degrees head-up tilt testing, patients with CFS had greater increases in heart rate, diastolic BP (p <0.001), mean BP (p <0.01), and total peripheral resistance index (p <0.05) than controls and greater decreases in stroke index (p <0.05).

Syncope or near syncope [fainting spell owing to reduced blood flow to brain] was not observed.

In conclusion, this study found that adolescents with CFS have significant abnormalities of cardiovascular regulation in response to mild orthostatic stress, differentiating them from healthy controls.