Background An autonomic nervous system (ANS) dysfunction with a relentless sympathetic hyperactivity (SH) is found in fibromyalgia (FM). Although SH is a key feature of many heart diseases, no reliable data is found about cardiovascular risk in FM. An exercise places an increased demand on the cardiovascular system that runs, in part, by precise alterations in activity of the ANS. Possible aberrances in cardiovascular response (CR) during the exercise test in FM patients are of considerable interest.
Objectives The purpose of this study was to investigate the CR to submaximal exercise stress test in FM women.
Methods The study involved 52 FM women (ACR 1990 criteria) aged 35.4±5.8 (M±SD) yrs and 30 healthy controls (HCs) (all women) aged 36.8±5.6 yrs. A submaximal bicycle ergometry test with predominant endpoint determined as 80%of the predicted maximal heart rate (HR) was performed. An electronically braked stationary bicycle (SCHILLER, Switzerland) was used. Protocol included initial warm-up, a progressive uninterrupted exercise with increasing loads in 25W every 3 minutes and a recovery period (RP). Heart rate (HR), blood pressure (BP) and ECG monitoring were performed during exercise and RP. Maximal BP (mm Hg), time to reach (TR) baseline HR and BP in seconds (s) were detected. ST segment deviation levels in milivolt (mV) for subthreshold depression (<0,1) and elevation (<0,2) and ischemic depression (≥0,1) were estimated.
Results No significant differences between baseline BP and HR in the investigated groups were found. The load to rich protocol endpoint (W) was lower in HCs (102.4±20.2 vs. 145.3±17.4, p<0.05). Though maximal BP during exercise was insignificantly higher in FM women compared to HCs (178.6±29.8 vs. 163.1±14.9, p>0.05), TR baseline BP was longer in women with FM (912.3±167.9 vs. 324.2±87.6, p<0.05) as well as TR baseline HR (724.5±134.2 vs. 398.3±107.1, p<0.05). Subthreshold ST segment depression was registered in 28 FM women (53.8%) and in 2 HCs (6.6%) during ergometry. Subthreshold ST segment elevation occurred in 5 HCs (16.7%) and in 9 FM women (17.3%). Among FM women 2 (3.8%) were found to occur reversible ischemic ST segment depression during exercise and 5 (9.6%) in RP compared to none among HCs. Supraventricular extrasystoles were registered in 21 (40.4%) FM women during ergometry and in 8 (15.4%) patients in RP compared to 4 (13.3%) among HCs during exercise only. Rare isolated ventricular premature beats were registered in 6 (33.3%) FM women in RP when none among HCs was found to have such rhythm change.
Conclusions CR to submaximal ergometry test in FM women is characterized by prolonged BP and HR restoration. Supraventricular and rare isolated ventricular premature beats and different ST segment deviations were registered in FM women during protocol execution including reversible ischemic ST segment depression.
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Disclosure of Interest None declared