AUTHOR=Chen Songwen , Meng Guannan , Doytchinova Anisiia , Wong Johnson , Straka Susan , Lacy Julie , Li Xiaochun , Chen Peng-Sheng , Everett IV Thomas H. 

TITLE=Skin Sympathetic Nerve Activity and the Short-Term QT Interval Variability in Patients With Electrical Storm

JOURNAL=Frontiers in Physiology

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2021.742844

DOI=10.3389/fphys.2021.742844

ISSN=1664-042X

ABSTRACT=<p><bold>Background</bold>: Skin sympathetic nerve activity (SKNA) and QT interval variability are known to be associated with ventricular arrhythmias. However, the relationship between the two remains unclear.</p><p><bold>Objective</bold>: The aim was to test the hypothesis that SKNA bursts are associated with greater short-term variability of the QT interval (STVQT) in patients with electrical storm (ES) or coronary heart disease without arrhythmias (CHD) than in healthy volunteers (HV).</p><p><bold>Methods</bold>: We simultaneously recorded the ECG and SKNA during sinus rhythm in patients with ES (<italic>N</italic> = 10) and CHD (<italic>N</italic> = 8) and during cold-water pressor test in HV (<italic>N</italic> = 12). The QT and QTc intervals were manually marked and calculated within the ECG. The STVQT was calculated and compared to episodes of SKNA burst and non-bursting activity.</p><p><bold>Results</bold>: The SKNA burst threshold for ES and HV was 1.06 ± 1.07 and 1.88 ± 1.09 μV, respectively (<italic>p</italic> = 0.011). During SKNA baseline and burst, the QT/QTc intervals and STVQT for ES and CHD were significantly higher than those of the HV. In all subjects, SKNA bursts were associated with an increased STVQT (from 6.43 ± 2.99 to 9.40 ± 5.12 ms, <italic>p</italic> = 0.002 for ES; from 9.48 ± 4.40 to 12.8 ± 5.26 ms, <italic>p</italic> = 0.016 for CHD; and from 3.81 ± 0.73 to 4.49 ± 1.24 ms, <italic>p</italic> = 0.016 for HV). The magnitude of increased STVQT in ES (3.33 ± 3.06 ms) and CHD (3.34 ± 2.34 ms) was both higher than that of the HV (0.68 ± 0.84 ms, <italic>p</italic> = 0.047 and <italic>p</italic> = 0.020).</p><p><bold>Conclusion</bold>: Compared to non-bursting activity, SKNA bursts were associated with a larger increase in the QTc interval and STVQT in patients with heart disease than in HV.</p>