To the Editor,
First, we would like to thank you for your interest in our article entitled, “Evaluation of Tp-e Interval, Tp-e/QT Ratio and Tp-e/QTc Ratio in Patients with Mitral Valve Stenosis Before and After Balloon Valvuloplasty” (1).
It has been demonstrated that sympathetic nervous system activation increases the Tp-e interval, and this increase immediately develops after stimulation (2). Previous studies have shown that sympathetic activity in patients with mitral stenosis (MS) reduced by balloon valvuloplasty after 1 week (3, 4). Moreover, it has been shown that the effects of reduction in sympathetic activity after balloon valvuloplasty occur much earlier. Özdemir et al. (5) showed significant improvement in heart rate variability parameters 1 day after balloon valvuloplasty in their study. The investigators attributed these results to reduced sympathetic activity and increased parasympathetic activity after balloon valvuloplasty. Similarly, our study showed that there was a significant reduction in Tp-e interval 1 day after balloon valvuloplasty in patients with severe MS. The reduction in sympathetic activity after balloon valvuloplasty in such a short time, such as 1 day, and the important parameters of ventricular repolarization are the distinctive results of our study .
As noted, our study could be more valuable if the sympathetic biomarker level was observed and correlated with the other parameters. Only those who had a sinus rhythm and did not have any additional cardiovascular disease were included in the study. Therefore, the number of patients in our study was relatively low. However, the analyses were performed after power analysis of the group sample sizes.
References
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