To the Editor,
I thank the journal readers for their great interest in our original article titled “Tp-e interval and Tp-e/QTc ratio as novel surrogate markers for prediction of ventricular arrhythmic events in hypertrophic cardiomyopathy” recently published in The Anatolian Journal of Cardiology (1).
First, our main purpose was to evaluate the association of repolarization dispersion represented by Tp-e interval with ventricular arrhythmic events (VAEs) in patients with hypertrophic cardiomyopathy (HCM). QTc duration derived by applying Bazett’s formula has been already reported to be associated with VAEs in HCM (2). Second, because we designed this study according to the current 2014 European Society of Cardiology guidelines on diagnosis and management of HCM, non-sustained ventricular tachycardia (three or more consecutive ventricular extra systoles at a rate of ≥120 beats/min, terminating spontaneously within 30 s) was defined as VAEs detected by holter monitoring or implantable cardioverter defibrillator (ICD) together with sustained ventricular tachycardia (>30 sec or hemodynamic collapse) (3). Third, unfortunately, as population of our study is relatively small, we did not performe subgroup analysis for patients with ICD concerning VAEs. Fourth, inter- and intra-observer coefficients of variation in our study were 3.2% and 2.8%, respectively. Fifth, as we mentioned in the method section of our article, normally distributed variables were represented as mean±standard deviation including Tp-e interval in Table 1. Therefore, Pearson correlation test was used to indicate the correlation of maximal left ventricular thickness with Tp-e interval and Tp-e/QTc ratio. Finally, it is difficult to make a final decision according to our hypothesis-generating study with relatively limited study population. Hence, these findings need to be confirmed in further and larger prospective multicenter trials. Thereafter, these parameters may be used more in clinical practice for predicting VAEs in HCM.
Conflicts of interest: The author has no conflicts of interest to disclose.
References
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