Assessment of cardiac sympathovagal activity in the patients suffering from ankylosing spondylitis

Abstract

Background: Ankylosing spondylitis (AS) is an autoimmune disease which leads to the involvement of skeletal, cardiac, nervous tissues, and other systemic diseases. Aims and Objectives: This study was conducted to assess the cardiac sympathovagal responses in the AS patients using Valsalva maneuver (VM) and tilt-table test (TTT). Materials and Methods: A total of 30 AS patients having Bath AS Disease Activity Index of ≥4 were included in this study. The same numbers of age-and sex-matched controls were also selected. The blood pressure (BP) and electrocardiogram were recorded during VM and TTT. The Valsalva ratio and 30:15 ratio were calculated. Results: During VM, there is a statistically significant decrease in the Valsalva ratio in the cases (P < 0.05). After TTT, there is a significant decrease in 30:15 ratio and significant increase in systolic BP (SBP) in the cases (P < 0.05). Conclusion: The Valsalva ratio in the cases is decreased indicating the parasympathetic loss which is further supported by the decrease in 30:15 ratio observed after TTT. The increase in SBP in cases also supports the shifting of sympathovagal balance toward the sympathetic side.