Cardiac arrhythmias secondary to hormone therapy in trans women

Sex hormones and reproductive factors with cardiac arrhythmia and ECG indices: a mendelian randomization study

BACKGROUND

Sex is a determinant of the incidence and etiology of arrhythmia. Observational and basic studies suggest that sex hormones are essential in this process; however, the relationship between sex hormones and arrhythmia remains unclear. Mendelian randomization (MR) was used to investigate the causal relationships between sex hormone levels, arrhythmia, and electrocardiographic (ECG) indices.

METHODS

Large genome-wide association studies (GWAS) data on sex hormones, stratified by sex, from the UK biobank consortium, were used as exposure data, and data on atrial fibrillation (AF), atrioventricular block, sick sinus syndrome, paroxysmal tachycardia, and ECG indices were obtained from the FinnGen consortium and summarized large GWAS data. Inverse variance weighting or wald odds was used as the primary analytical method, and weighted medians and MR-Egger regression were used for complementary analyses. The results of the MR of sex hormones and AF from different sources were analyzed using a meta-analysis. Summary-data-based MR analysis was utilized to explore the relationship between sex-hormone related drugs and arrhythmia.

RESULTS

In men, genetically predicted higher estradiol concentrations were associated with a lower risk of AF (odds ratio: 0.908 [0.852-0.967]; p = 0.0029], whereas genetically predicted higher concentrations of total testosterone were associated with lower heart rate variability. Sex hormones showed no association with atrioventricular block, sick sinus syndrome, paroxysmal tachycardia, resting heart rate, P wave duration, P wave terminal force in lead V1 [PTFV1], PR interval, QRS duration, QTc [QT interval corrected by heart rate], ST duration, spatial [spQRSTa] and frontal [fQRSTa] QRS-T angles in males. In females, there was no significant evidence that sex hormones are associated with arrhythmias or ECG indices.

CONCLUSION

In this study, we identified a potential causal relationship between estradiol and the risk of AF in males. However, there was no significant association between sex hormones and either arrhythmias or ECG indices in females. These results suggested that sex hormones may play a limited role in cardiac arrhythmias, which requires further verification.

Prevalence of Cardiac Arrhythmias in Transgender and Nonbinary Adult Community Health Center Patients

Purpose: Sex differences in cardiac arrhythmias are well established. This study aimed to explore the prevalence of arrhythmias in transgender and nonbinary (TGNB) adults. Methods: This cross-sectional study utilized electronic medical records from a center specializing in TGNB care. Adults aged ≥18 years with ≥2 medical visits between January 1, 2010, and December 31, 2021, were categorized into self-reported gender groups: TGNB (transgender men, transgender women, nonbinary [NB]-assigned male at birth, NB-assigned female at birth), cisgender men, and cisgender women. The primary outcome was any arrhythmia using age- and race-adjusted regression models comparing transgender patients with cisgender men and cisgender women. Prevalence of arrhythmias was explored in transgender people with a gender-affirming hormone therapy (GAHT) prescription. Results: The sample included 49,862 adults, with 7121 (14%) TGNB persons. Median age was 28 years. Prevalence of arrhythmias was low (0.7-1.4% NB persons, 1.4-1.5% transgender persons). After adjustment, transgender women and transgender men had similar odds of any arrhythmia compared with cisgender men (transgender women: adjusted odds ratio [aOR] 0.89, 95% confidence interval [CI] 0.63-1.24, p = 0.52; transgender men: aOR 1.17, 95% CI 0.82-1.62, p = 0.37), but higher odds of any arrhythmia compared with cisgender women (transgender women: aOR 1.65, 95% CI 1.13-2.34, p = 0.01; transgender men: aOR 2.15, 95% CI 1.48-3.04, p < 0.001). Prevalence of arrhythmias appeared similar among transgender adults regardless of GAHT use (transgender men: 1.5% vs 1.9%, transgender women: 1.2% vs 2.1%). Conclusion: Further research examining arrhythmias in TGNB patients and across gender minority subgroups is warranted, including longitudinal studies evaluating the potential impact of GAHT.

Cardiovascular outcomes in transgender individuals in Sweden after initiation of gender-affirming hormone therapy

AIMS

We compared the incidence of cardiovascular disease (CVD) in transgender participants with a diagnosis of gender dysphoria (GD) with and without gender-affirming hormone therapy (GAHT) to the incidence observed in the general population.

METHODS AND RESULTS

The population-based cohort included all individuals >10 years in Sweden linked to Swedish nationwide healthcare Registers (2006-16). Two comparator groups without GD/GAHT were matched (1:10) on age, county of residence, and on male and female birth-assigned sex, respectively. Cox proportional models provided hazard ratios (HRs) and 95% confidence intervals (CI) for CVD outcomes. Among 1779 transgender individuals [48% birth-assigned males (AMAB), 52% birth-assigned females (AFAB)], 18 developed CVD, most of which were conduction disorders. The incidence of CVD for AFAB individuals with GD was 3.7 per 1000 person-years (95% CI: 1.4-10.0). Assigned male at birth individuals with GD had an incidence of CVD event of 7.1 per 1000 person-years (95% CI: 4.2-12.0). The risk of CVD event was 2.4 times higher in AMAB individuals (HR: 2.4, 95% CI: 1.3-4.2) compared with cisgender women, and 1.7 higher compared with cisgender men (HR: 1.7, 95% CI: 1.0-2.9). Analysis limited to transgender individuals without GAHT yielded similar results to those with GAHT treatment.

CONCLUSION

The incidence of CVD among GD/GAHT individuals was low, although increased compared with matched individuals without GD and similar to the incidence among GD/no GAHT individuals, thus not lending support for a causal relationship between treatment and CVD outcomes. Larger studies with longer follow-up are needed to verify these findings, as well as possible effect modification by comorbidity.

Gut Microbiota and Metabolites in Atrial Fibrillation Patients and Their Changes after Catheter Ablation

The gut microbiota has been shown to be associated with multiple cardiovascular diseases, but there is little research on the gut microbiota and atrial fibrillation (AF); thus, how the gut microbiota and metabolites change in AF patients after catheter ablation is unclear. In this study, we used 16S rRNA high-throughput sequencing and nontargeted metabolomic detection to conduct horizontal and longitudinal analyses of the gut microbiota and metabolites of AF patients. Compared with a control group, species richness and diversity increased significantly in AF patients. Among them, opportunistic pathogenic bacteria, such as Klebsiella, Haemophilus, Streptococcus, and Enterococcus, were significantly increased, and symbiotic bacteria, such as Agathobacter and Butyrivibrio, were significantly reduced. After catheter ablation, intestinal symbiotic bacteria (Lactobacillus, Agathobacter, Lachnospira, etc.) were increased in most AF patients, while pathogenic bacteria (Ruminococcus, etc.) were reduced. Moreover, in AF patients, caffeine, which was negatively correlated with Klebsiella, was downregulated, and estradiol and ascorbic acid, which were positively correlated with Agathobacter, were also downregulated. After catheter ablation, citrulline, which was positively correlated with Ralstonia and Lactobacillus, was increased. Oleanolic acid, which was negatively correlated with Ralstonia was downregulated. In conclusion, our results not only show overall changes in the gut microbiota and metabolites in AF patients but also indicate their changes in the short term after catheter ablation. These data will provide novel possibilities for the future clinical diagnosis and treatment of AF.

IMPORTANCE Gut microbiota and metabolites play a very important role in human health and can not only assess human health but also treat and prevent diseases. We analyzed the characteristics of the microbiota and metabolites in the human gut and found the effect of disease on gut microbiota and metabolites, which may be of important value in the pathogenesis of atrial fibrillation. At the same time, we also observed dynamic changes in gut microbiota and metabolites with the intervention of catheter ablation, which was not available in previous studies.

Arrhythmias in Female Patients: Incidence, Presentation and Management

There is a growing appreciation for differences in epidemiology, treatment, and outcomes of cardiovascular conditions by sex. Historically, cardiovascular clinical trials have under-represented females, but findings have nonetheless been applied to clinical care in a sex-agnostic manner. Thus, much of the collective knowledge about sex-specific cardiovascular outcomes result from post hoc and secondary analyses. In some cases, these investigations have revealed important sex-based differences with implications for optimizing care for female patients with arrhythmias. This review explores the available evidence related to cardiac arrhythmia care among females, with emphasis on areas in which important sex differences are known or suggested. Considerations related to improving female enrollment in clinical trials as a way to establish more robust clinical evidence for the treatment of females are discussed. Areas of remaining evidence gaps are provided, and recommendations for areas of future research and specific action items are suggested. The overarching goal is to improve appreciation for sex-based differences in cardiac arrhythmia care as 1 component of a comprehensive plan to optimize arrhythmia care for all patients.

Protective effect of estradiol copreservation against kidney ischemia-reperfusion injury

Ischemia-reperfusion injury (IRI) is the major cause of delayed graft function (DGF) during the posttransplantation period. Estradiol (E2) prevents IRI-induced kidney dysfunction and tissue injury. However, many side effects limit E2's in vivo application. Recent evidence uncovers E2's expanded use in the field of transplantation. We aimed to study if and how E2 exerts protective activity during the period of kidney organ preservation. The autologous kidney transplant model in rats was first established. Rats were divided into 5 groups: normal group (N), sham group (sham), static cold storage (SCS) 4 hours group (control), SCS 4 hours + ethanol (1 µL/mL) group (solvent), and SCS 4 hours + ethanol (1 µL/mL) + E2 (1000 ng/mL) group (E2). ERα expression under hypothermia was measured by western blotting. Moreover, biochemical analyses of plasma levels of creatinine, BUN, estradiol, and testosterone were examined. Among all groups, kidney tissues were collected and processed for further western blot analysis about ERα, eNOS, Bcl-2, and Bax expression, histological analyses such as H&E staining to evaluate pathological severity. In addition, a TUNEL assay is performed to evaluate apoptosis. E2 copreservation upregulated ERα expression under hypothermia. Moreover, E2 copreservation reduced levels of creatinine and BUN in plasma but without affecting estradiol and testosterone. Further, E2 copreservation increased expression of eNOS and antiapoptotic Bcl-2 and decreases expression of proapoptotic Bax. E2 copreservation significantly inhibited IRI-induced apoptosis and evidently improved pathological severity in the kidney of rats. E2 copreservation exerts protective activity against IRI-induced pro-inflammatory and proapoptotic effects in kidneys during organ preservation time and improves transplanted kidney function.

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.

Lactation Induction in a Transgender Woman Wanting to Breastfeed: Case Report

CONTEXT

Breastfeeding is known to have many health and wellness benefits to the mother and infant; however, breastfeeding in trans women has been greatly under-researched.

OBJECTIVE

To review potential methods of lactation induction in trans women wishing to breastfeed and to review the embryological basis for breastfeeding in trans women.

DESIGN

This article summarizes a case of successful lactation in a trans woman, in which milk production was achieved in just over 1 month.

SETTING

This patient was followed in an outpatient endocrinology clinic.

PARTICIPANT

A single trans woman was followed in our endocrinology clinic for a period of 9 months while she took hormone therapy to help with lactation.

INTERVENTIONS

Readily available lactation induction protocols for nonpuerpural mothers were reviewed and used to guide hormone therapy selection. Daily dose of progesterone was increased from 100 mg to 200 mg daily. The galactogogue domperidone was started at 10 mg 3 times daily and titrated up to effect. She was encouraged to use an electric pump and to increase her frequency of pumping.

MAIN OUTCOME MEASURE

Lactation induction.

RESULTS

At one month, she had noticed a significant increase in her breast size and fullness. Her milk supply had increased rapidly, and she was producing up to 3 to 5 ounces of milk per day with manual expression alone.

CONCLUSIONS

We report the second case in the medical literature to demonstrate successful breastfeeding in a trans woman through use of hormonal augmentation.

New aspects of endocrine control of atrial fibrillation and possibilities for clinical translation

Hormones are potent endo-, para-, and autocrine endogenous regulators of the function of multiple organs, including the heart. Endocrine dysfunction promotes a number of cardiovascular diseases, including atrial fibrillation (AF). While the heart is a target for endocrine regulation, it is also an active endocrine organ itself, secreting a number of important bioactive hormones that convey significant endocrine effects, but also through para-/autocrine actions, actively participate in cardiac self-regulation. The hormones regulating heart-function work in concert to support myocardial performance. AF is a serious clinical problem associated with increased morbidity and mortality, mainly due to stroke and heart failure. Current therapies for AF remain inadequate. AF is characterized by altered atrial function and structure, including electrical and profibrotic remodelling in the atria and ventricles, which facilitates AF progression and hampers its treatment. Although features of this remodelling are well-established and its mechanisms are partly understood, important pathways pertinent to AF arrhythmogenesis are still unidentified. The discovery of these missing pathways has the potential to lead to therapeutic breakthroughs. Endocrine dysfunction is well-recognized to lead to AF. In this review, we discuss endocrine and cardiocrine signalling systems that directly, or as a consequence of an underlying cardiac pathology, contribute to AF pathogenesis. More specifically, we consider the roles of products from the hypothalamic-pituitary axis, the adrenal glands, adipose tissue, the renin–angiotensin system, atrial cardiomyocytes, and the thyroid gland in controlling atrial electrical and structural properties. The influence of endocrine/paracrine dysfunction on AF risk and mechanisms is evaluated and discussed. We focus on the most recent findings and reflect on the potential of translating them into clinical application.

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.

Burden of arrythmias in transgender patients hospitalized for gender-affirming surgeries

BACKGROUND

We sought to describe the burden of arrhythmias and their impact on in-hospital outcomes in transgender patients who underwent gender re-assignment surgery.

METHODS

The study utilized data from the National Inpatient Sample from January 2012 to September 2015.

RESULTS

16 555 adult transgender patients were included in this study. A total of 610 adults developed arrhythmia out of which atrial fibrillation (N = 475, 2.87%) was the most frequent arrhythmia. In-hospital mortality increased substantially with arrhythmias.

CONCLUSIONS

New-onset arrythmias, while infrequent in the inpatient setting is associated with significantly higher in-hospital mortality and resource utilization.