Androgen Deprivation Therapy for Prostatic Cancer in Patients With Torsades de Pointes

Transient Hypogonadism Is Associated With Heart Rate-Corrected QT Prolongation and Torsades de Pointes Risk During Active Systemic Inflammation in Men

Background

Systemic inflammation and male hypogonadism are 2 increasingly recognized “nonconventional” risk factors for long‐QT syndrome and torsades de pointes (TdP). Specifically, inflammatory cytokines prolong, while testosterone shortens the heart rate–corrected QT interval (QTc) via direct electrophysiological effects on cardiomyocytes. Moreover, several studies demonstrated important interplays between inflammation and reduced gonad function in men. We hypothesized that, during inflammatory activation in men, testosterone levels decrease and that this enhances TdP risk by contributing to the overall prolonging effect of inflammation on QTc.

Methods and Results

We investigated (1) the levels of sex hormones and their relationship with inflammatory markers and QTc in male patients with different types of inflammatory diseases, during active phase and recovery; and (2) the association between inflammatory markers and sex hormones in a cohort of male patients who developed extreme QTc prolongation and TdP, consecutively collected over 10 years. In men with active inflammatory diseases, testosterone levels were significantly reduced, but promptly normalized in association with the decrease in C‐reactive protein and interleukin‐6 levels. Reduction of testosterone levels, which also inversely correlated with 17‐β estradiol over time, significantly contributed to inflammation‐induced QTc prolongation. In men with TdP, both active systemic inflammation and hypogonadism were frequently present, with significant correlations between C‐reactive protein, testosterone, and 17‐β estradiol levels; in these patients, increased C‐reactive protein and reduced testosterone were associated with a worse short‐term outcome of the arrhythmia.

Conclusions

During systemic inflammatory activation, interleukin‐6 elevation is associated with reduced testosterone levels in males, possibly deriving from an enhanced androgen‐to‐estrogen conversion. While transient, inflammatory hypotestosteronemia is significantly associated with an increased long‐QT syndrome/TdP risk in men.

Androgens, QT, sex and ventricular repolarization-a double-edged sword: A case series

The prevalence and incidence of cardiac pro-arrhythmic disorders are often influenced by sex due to specific effects on the QT interval. Androgens shorten QT, which may be protective against acquired long QT syndromes and their related arrhythmias in men such as torsade de pointes (TdP). On the other hand, androgens can potentiate Brugada and early repolarization syndromes, which are most prevalent in men. In this case series, we highlight four male patients with aborted SCD in the setting of abnormal testosterone status; two patients with TdP in a setting of testosterone deprivation (of which one drug-induced) and 2 patients with ventricular fibrillation associated with exogenous androgenic booster (Tribulus terrestris) intake. From this case series, we review the current available literature of the effects of androgen as a double-edged sword on the QTc interval and emphasize the importance of QTc monitoring in this subset of patients.

Anti-Ro/SSA Antibodies and the Autoimmune Long-QT Syndrome

Autoimmunity is increasingly recognized as a novel pathogenic mechanism for cardiac arrhythmias. Several arrhythmogenic autoantibodies have been identified, cross-reacting with different types of surface proteins critically involved in the cardiomyocyte electrophysiology, primarily ion channels (autoimmune cardiac channelopathies). Specifically, some of these autoantibodies can prolong the action potential duration leading to acquired long-QT syndrome (LQTS), a condition known to increase the risk of life-threatening ventricular arrhythmias, particularly Torsades de Pointes (TdP). The most investigated form of autoimmune LQTS is associated with the presence of circulating anti-Ro/SSA-antibodies, frequently found in patients with autoimmune diseases (AD), but also in a significant proportion of apparently healthy subjects of the general population. Accumulating evidence indicates that anti-Ro/SSA-antibodies can markedly delay the ventricular repolarization via a direct inhibitory cross-reaction with the extracellular pore region of the human-ether-a-go-go-related (hERG) potassium channel, resulting in a higher propensity for anti-Ro/SSA-positive subjects to develop LQTS and ventricular arrhythmias/TdP. Recent population data demonstrate that the risk of LQTS in subjects with circulating anti-Ro/SSA antibodies is significantly increased independent of a history of overt AD, intriguingly suggesting that these autoantibodies may silently contribute to a number of cases of ventricular arrhythmias and cardiac arrest in the general population. In this review, we highlight the current knowledge in this topic providing complementary basic, clinical and population health perspectives.

The Impact of Testosterone on the QT Interval: A Systematic Review

Humans and mammals have sex-specific differences in cardiac electrophysiology, linked to the action of sex hormones in the cardiac muscle. These hormones can upregulate or downregulate the expression of ionic channels modulating the cardiac cycle through genomic and non-genomic interactions. Systematic search in PubMed, Medline and EMBASE including keywords pertaining to testosterone and QT interval. Included experimental studies and observation studies and case reports presenting the results of testosterone administration, excess or deficiency in humans and animals. Testosterone has been shown to shorten the action potential duration, by enhancing the expression of K⁺ channels and downregulating I_CaL increasing the repolarization reserve of the cardiac muscle. This effect has been observed in both genders and animals. Testosterone deficient states can promote arrhythmogenesis. The evidence in this paper may be used to guide clinical considerations, such as increased clinical surveillance of patients in testosterone deficient states using ECG.

Drug-Associated QTc Prolongation in Geriatric Hospitalized Patients: A Cross-Sectional Study in Internal Medicine

Objective

The primary objectives of this prospective cross-sectional study were to estimate the prevalence of drug-related long QT syndrome (LQTS) and the prevalence of use of QT-prolonging drugs in older patients admitted to an internal medicine unit.

Methods

We screened consecutive patients hospitalized in an internal medicine unit over a 2-year period. A 12-lead electrocardiogram using an electrocardiograph with automated measurement of QT interval was recorded. Patient characteristics (age, sex, body mass index), drug treatments, and variables associated with QT interval prolongation, including hypothyroidism, type 2 diabetes mellitus, and cardiac disease, were also recorded. In addition, we also measured serum levels of potassium, calcium, magnesium, and creatinine at admission. The list of medications known to cause or to contribute to LQTS was obtained from CredibleMeds^®.

Results

A total of 243 patients were enrolled: mean ± standard deviation age, 79.65 ± 8.27 years; males, n = 121 (40.8%); mean corrected QT (QTc) interval, 453.70 ± 43.77 ms. Overall, 89/243 (36.6%) patients had a prolonged QTc interval, with 29/243 (11.9%) having QTc interval prolongation > 500 ms (11.9%). A vast majority were prescribed at least one QT-prolonging drug (218/243 [89.7%]), whereas 74/218 (30.5%) were receiving at least one medication with a known risk of Torsades des Pointes (TdP). Proton pump inhibitors were the second most commonly prescribed class of drugs. After logistic regression, male sex was independently associated with LQTS (odds ratio 2.85; 95% confidence interval 1.56–5.22; p = 0.001).

Conclusions

The prevalence of LQTS with QTc interval > 500 ms in geriatric inpatients was > 10%, and QT-prolonging drugs were frequently used on admission (more than 30% of patients were receiving drugs with a known risk of TdP).

Supplementary Information

The online version contains supplementary material available at 10.1007/s40801-021-00234-x.

Syncope due to non-sustained episodes of Torsade de Pointes associated to androgen-deprivation therapy use: a case presentation

BACKGROUND

Abiraterone is a medication frequently used for metastatic castrate-resistant prostate cancer. We report a case of non-sustained episodes of TdP associated with severe hypokalemia due to androgen-deprivation therapy. Few case presentations describe this association; the novelty lies in the potentially lethal cardiovascular events among cancer patients receiving hormonal therapy.

CASE PRESENTATION

A 70-year-old male presented with recurrent syncope without prodrome. ECG revealed frequent ventricular ectopy, non-sustained episodes of TdP, and severe hypomagnesemia and hypokalemia. During potassium and magnesium infusion for repletion, the patient underwent temporary transvenous atrial pacing. As part of the work-up, coronary angiography revealed a mild coronary artery disease, and transthoracic echocardiogram showed a moderately depressed ejection fraction. After electrolyte disturbances were corrected, the QT interval normalized, and transvenous pacing was no longer necessary. Abiraterone was discontinued during the admission, and the patient returned to baseline.

CONCLUSIONS

Cancer treatment is complex and requires a multidisciplinary approach. We presented a case of non-sustained TdP associated with androgen-deprivation therapy in an elderly patient with mild coronary artery disease and moderately reduced ejection fraction. Close follow-up and increased awareness are required in patients with hormonal treatment, especially in the setting of other cardiovascular risk factors.

Sexual Dimorphisms, Anti-Hormonal Therapy and Cardiac Arrhythmias

Significant variations from the normal QT interval range of 350 to 450 milliseconds (ms) in men and 360 to 460 ms in women increase the risk for ventricular arrhythmias. This difference in the QT interval between men and women has led to the understanding of the influence of sex hormones on the role of gender-specific channelopathies and development of ventricular arrhythmias. The QT interval, which represents the duration of ventricular repolarization of the heart, can be affected by androgen levels, resulting in a sex-specific predilection for acquired and inherited channelopathies such as acquired long QT syndrome in women and Brugada syndrome and early repolarization syndrome in men. Manipulation of the homeostasis of these sex hormones as either hormonal therapy for certain cancers, recreational therapy or family planning and in transgender treatment has also been shown to affect QT interval duration and increase the risk for ventricular arrhythmias. In this review, we highlight the effects of endogenous and exogenous sex hormones in the physiological and pathological states on QTc variation and predisposition to gender-specific pro-arrhythmias.

Testosterone use and shorter electrocardiographic QT interval duration in men living with and without HIV

OBJECTIVES

Testosterone usage (T-use) may alter risk factors for sudden cardiac death in men living with HIV (MLWH). Electrocardiographic QT interval prolongation, which could potentiate ventricular arrhythmias, has previously been associated with HIV infection and, separately, with low testosterone levels. We investigated whether T-use shortens the QT interval duration in MLWH and HIV-uninfected men.

METHODS

We utilized data from the Multicenter AIDS Cohort Study, a prospective, longitudinal study of HIV infection among men who have sex with men. Multivariable linear regression analyses were used to evaluate associations between T-use and corrected QT interval (QTc) duration.

RESULTS

Testosterone usage was more common in MLWH compared with HIV-uninfected men (19% vs. 9%). In a multivariable regression analysis, T-use was associated with a 5.7 ms shorter QT interval [95% confidence interval (CI): -9.5 to -1.9; P = 0.003). Furthermore, stronger associations were observed for prolonged duration of T-use and recent timing of T-use.

CONCLUSIONS

This study is the first known analysis of T-use and QTc interval in MLWH. Overall, our data demonstrate that recent T-use is associated with a shorter QTc interval. Increased T-use duration above a threshold of ≥ 50% of visits in the preceding 5 years was associated with a shorter QTc interval while lesser T-use duration was not.