Changes in left ventricular repolarization after short-term testosterone replacement therapy in hypogonadal males

Abstract

Background and aim Evidences suggest that androgen deficiency is associated with sudden cardiac death (SCD). Our purpose was to analyse some electrocardiographic (ECG) markers of repolarization phase in hypogonadal patients either at baseline or after testosterone replacement therapy (TRT). Patients and Methods Baseline and after 6 months of testosterone replacement therapy, 14 hypogonadal patients and 10 age-matched controls underwent a short-term ECG recordings at rest and immediately after a maximal exercise test. The following ECG parameters have been collected: QTe (the interval between the q wave the end of T wave), QTp (the interval between the q wave and the peak of T wave), and Te (the interval between the peak and the end of T wave). Results At baseline, in the hypogonadal patients, corrected QTe and QTp values were longer at rest than in the controls at rest ( p < 0.05), whereas, during the recovery phase, only the QTp remained significantly longer ( p < 0.05). After TRT, hypogonadal patients showed an improvement only in Te ( p < 0.05). Conversely, any difference between hypogonadal patients and control subjects was found with respect to the markers of temporal dispersion of repolarization phases, except for a worse QTp → Te coherence ( p = 0.001) obtained during the recovery phase. Conclusions In conclusion, at rest, hypogonadal patients suffer from a stable increase in the myocardial repolarization phase without an increase in its temporal dispersion and, hence, the SCD risk seems to be low.

Evolution of Electrocardiographic Repolarization Parameters During Antiandrogen Therapy in Patients with Prostate Cancer and Hypogonadism

“…Taking into account the findings of Piccirillo et al [35], who studied 14 hypogonadal patients and 10 age-matched controls and found no difference in Tpe, we can assume that the significant prolongation of Tpe and Tpe/QT in our study group A reflects the effect of the combination of degarelix with enzalutamide, not of the hypogonadism itself.…”

Time‐ and frequency‐domain analysis of repolarization phase during recovery from exercise in healthy subjects

“…To calculate repolarization variables a template method has been used 17 . We designed and produced a software for data acquisition, storage, and analysis with the LabView program (National Instruments), which applies the technical recommendation of consensus guidance endorsed by European Heart Rhythm Association jointly with the European Society of Cardiology Working Group on cardiac cellular electrophysiology, as described in detail in previous papers 1,2,8‐13,18,19 …”

“…Therefore, we measured the following intervals from the respective time series in ECG recordings: RR, QTe, QTp, and Te; QTe was obtained measuring the interval from the Q‐wave to the T‐wave end; QTp was obtained measuring the interval from the Q‐wave to the T‐wave peak; Te was obtained from T peak to end of T wave (Figures 1 and 2). 7‐13 To identify the repolarization intervals, we used a software originally proposed by Berger 17 and validated in other subsequently studies 1 . We therefore calculated mean, variance, and standard deviation (QTe SD , QTp SD , and Te SD ) values for each of these repolarization phase intervals 1 ; consequently, we calculated the QTe, QTp, and Te variability index (QTeVI, QTpVI, and TeVI) 1,17 …”

“…Finally, linear regression was used to calculate QTe‐RR, QTpRR, and Te‐RR slopes (Figure 3). 9,13,26–29 …”

“…The repolarization phase is a complex phenomenon, with various ion channels and transporter mechanisms most of them under a strong autonomic modulation 4,5 . In fact, all the sodium, calcium, and potassium channels are able to adapt the QT duration in function of previous diastolic interval duration 6 but also of the autonomic control 7‐13 . Previous studies analyzed the repolarization phase during the first 10 minutes of exercise recovery in patients with congenital long QT syndrome 14‐16 focusing on ECG markers obtained from peak to the progressive reduction of exercise heart rate.…”