Atrial Fibrillation and Ventricular Arrhythmias: Sex Differences in Electrophysiology, Epidemiology, Clinical Presentation, and Clinical Outcomes

Gender and Age Differences in the Evaluation and Clinical Outcomes of Patients with Palpitations

BACKGROUND

Palpitations represent a common clinic complaint.

OBJECTIVE

To explore gender and age differences in the evaluation and outcomes of patients with palpitations in outpatient settings.

DESIGN/PARTICIPANTS

This is a retrospective observational study of 58,543 patients with no known structural cardiac disease or arrythmias presenting to primary care and cardiology clinics in an integrated health system in California with palpitations between January 2017 and December 2021. The primary and secondary endpoints were hospitalization for arrhythmia and all-cause mortality at 1 year. Multivariable logistic regression models evaluated the association between gender, age, and outcomes.

RESULTS

Men and women were equally as likely to be started on beta-blockers (adjusted OR 0.96, 95% CI 0.90-1.02) and evaluated with electrocardiograms (adjusted OR 0.95, 95% CI 0.90-1.01) and cardiac monitors (adjusted OR 1.04, 95% CI 0.99-1.08). Patients who completed Holter or event monitors had a lower rate of hospitalization for cardiovascular disease at 1 year than those without (2.3% vs. 2.7%, p = 0.001). At 1 year, women had a lower risk of all-cause mortality (adjusted OR 0.47, 95% CI 0.35-0.64) and hospitalization for atrial fibrillation (adjusted OR 0.47, 95% CI 0.30-0.72) and arrhythmias (adjusted OR 0.73, 95% CI 0.58-0.91) compared to men. Among older women and men (≥ 80 years), there was no significant difference in 1-year all-cause mortality (adjusted OR 0.57, 95% CI 0.29-1.12), hospitalization for atrial fibrillation (adjusted OR 0.58, 95% CI 0.17-1.97), or arrhythmias (adjusted OR 1.15, 95% CI 0.12-11.07).

CONCLUSIONS

There were no gender differences in referrals for cardiac monitoring or prescriptions for beta-blockers. Women had a better prognosis with a lower risk of hospitalization for arrhythmias and death at 1 year compared to men. However, 1-year risks for mortality and hospitalization for arrythmias among older women were comparable to those of older men, underscoring the importance of considering age and gender in managing patients with palpitations.

Sex differences in clinical features, utilization of oral anticoagulant agents, and 1-year outcome in Middle Eastern patients with atrial fibrillation

OBJECTIVE

Studies have revealed that sex can predict differences in multiple aspects of atrial fibrillation (AF). These differences are underreported in the Middle East. This study aims to describe sex-specific differences in risk factors, symptomatology, management, and outcomes in Middle Eastern patients with AF.

METHODS

The JoFib (Jordan-Atrial-Fibrillation) study is an observational, prospective, multicenter, nationwide registry in AF. Comparisons were made between female and male patients using Pearson chi-square and Mann-Whitney U tests. Multivariable regression models were constructed to investigate whether the female sex was predictive of any AF-related outcomes (all-cause death, cardiovascular death, ischemic stroke or systemic embolism [IS/SE], major bleeding, and clinically relevant non-major bleeding).

RESULTS

Of 2,020 patients with AF, 54% (n = 1091) were females. Females with AF were older (median age 71 vs. 69, p <.001), but had less heart failure (20.9% vs. 27.2%, p = .001) and coronary artery disease (7.5% vs. 14.7%, p <.001). Females with AF were more symptomatic (74.7% vs. 66.5%, p <.001) and frequently received anticoagulant therapy (84.4% vs. 78.9%, p = .001). Rhythm control was pursued less frequently in females (23.4% vs. 27.3%, p = .04). All studied outcomes occurred with similar frequencies in females and males, and sex was not significantly predictive of any outcome.

CONCLUSION

Females with AF are more symptomatic, yet they are treated less with rhythm control. Despite higher risk, females have similar risk-adjusted all-cause cardiovascular death and stroke rates compared to males. Future studies should explore how treatments and interventions can influence quality-of-life and cardiovascular outcomes in females with AF.

Italian Association of Hospital Cardiologists Position Paper 'Gender discrepancy: time to implement gender-based clinical management'

It has been well assessed that women have been widely under-represented in cardiovascular clinical trials. Moreover, a significant discrepancy in pharmacological and interventional strategies has been reported. Therefore, poor outcomes and more significant mortality have been shown in many diseases. Pharmacokinetic and pharmacodynamic differences in drug metabolism have also been described so that effectiveness could be different according to sex. However, awareness about the gender gap remains too scarce. Consequently, gender-specific guidelines are lacking, and the need for a sex-specific approach has become more evident in the last few years. This paper aims to evaluate different therapeutic approaches to managing the most common women's diseases.

Enhanced Ca2+-Driven Arrhythmias in Female Patients with Atrial Fibrillation: Insights from Computational Modeling

BACKGROUND AND AIMS

Substantial sex-based differences have been reported in atrial fibrillation (AF), with female patients experiencing worse symptoms, increased complications from drug side effects or ablation, and elevated risk of AF-related stroke and mortality. Recent studies revealed sex-specific alterations in AF-associated Ca2+ dysregulation, whereby female cardiomyocytes more frequently exhibit potentially proarrhythmic Ca2+-driven instabilities compared to male cardiomyocytes. In this study, we aim to gain a mechanistic understanding of the Ca2+-handling disturbances and Ca2+-driven arrhythmogenic events in males vs females and establish their responses to Ca2+-targeted interventions.

METHODS AND RESULTS

We incorporated known sex differences and AF-associated changes in the expression and phosphorylation of key Ca2+-handling proteins and in ultrastructural properties and dimensions of atrial cardiomyocytes into our recently developed 3D atrial cardiomyocyte model that couples electrophysiology with spatially detailed Ca2+-handling processes. Our simulations of quiescent cardiomyocytes show increased incidence of Ca2+ sparks in female vs male myocytes in AF, in agreement with previous experimental reports. Additionally, our female model exhibited elevated propensity to develop pacing-induced spontaneous Ca2+ releases (SCRs) and augmented beat-to-beat variability in action potential (AP)-elicited Ca2+ transients compared with the male model. Parameter sensitivity analysis uncovered precise arrhythmogenic contributions of each component that was implicated in sex and/or AF alterations. Specifically, increased ryanodine receptor phosphorylation in female AF cardiomyocytes emerged as the major SCR contributor, while reduced L-type Ca2+ current was protective against SCRs for male AF cardiomyocytes. Furthermore, simulations of tentative Ca2+-targeted interventions identified potential strategies to attenuate Ca2+-driven arrhythmogenic events in female atria (e.g., t-tubule restoration, and inhibition of ryanodine receptor and sarcoplasmic/endoplasmic reticulum Ca2+-ATPase), and revealed enhanced efficacy when applied in combination.

CONCLUSIONS

Our sex-specific computational models of human atrial cardiomyocytes uncover increased propensity to Ca2+-driven arrhythmogenic events in female compared to male atrial cardiomyocytes in AF, and point to combined Ca2+-targeted interventions as promising approaches to treat AF in female patients. Our study establishes that AF treatment may benefit from sex-dependent strategies informed by sex-specific mechanisms.

Associations of Serum Testosterone and Sex Hormone-binding Globulin With Incident Arrhythmias in Men From UK Biobank

CONTEXT

Sex hormones have been identified as cardiovascular risk factors, whereas the relationship between sex hormones and the risk of arrhythmias in men has not yet been well studied in the prospective cohort study.

OBJECTIVE

To analyze associations of serum testosterone and SHBG concentrations and calculate free testosterone (cFT) with arrhythmias in men.

METHODS

Sex hormones were measured at baseline from UK Biobank. Main outcomes were incidence of atrial fibrillation/flutter (AF), ventricular arrhythmia (VA), and bradyarrhythmia (BA).

RESULTS

Of 173 498 men (aged 37-73 years, followed for 11 years), 11 368 had incident AF, 1646 had incident VA, and 4788 had incident BA. Compared with the third quartiles, the lowest category of serum testosterone was associated with increased risks of AF (hazard ratio [HR], 1.06; 95% CI, 1.00-1.12) and BA (HR, 1.11; 95% CI, 1.02-1.20) after multivariable adjustment, but no VA. Likewise, similar associations were found between cFT values and AF and BA events. Furthermore, higher levels of cFT were associated with increased risks of AF (HR, 1.07; 95% CI, 1.02-1.13) and VA (HR, 1.18; 95% CI, 1.01-1.37). Higher SHBG concentrations were associated with increased risks of AF (HR, 1.44; 95% CI, 1.34-1.54), VA (HR, 1.27; 95% CI, 1.07-1.52), and BA (HR, 1.17; 95% CI ,1.05-1.29).

CONCLUSIONS

Lower levels of testosterone and cFT were associated with increased risk of AF and BA. Higher cFT levels were associated with increased risk of AF and VA. Higher SHBG levels were associated with increased risk of AF, VA, and BA.

Sex Differences in Mouse Cardiac Electrophysiology Revealed by Simultaneous Imaging of Excitation-Contraction Coupling

Males and females differ in the basic anatomy and physiology of the heart. Sex differences are evident in cardiac repolarization in humans; women have longer corrected QT and JT intervals. However, the molecular mechanisms that lead to these differences are incompletely understood. Here, we present that, like in humans, sex differences in QT and JT intervals exist in mouse models; female mice had longer corrected QT and JT intervals compared with age-matched males. To further understand the molecular underpinning of these sex differences, we developed a novel technology using fluorescent confocal microscopy that allows the simultaneous visualization of action potential, Ca2+ transients, and contractions in isolated cardiomyocytes at a high temporal resolution. From this approach, we uncovered that females at baseline have increased action potential duration, decreased Ca2+ release and reuptake rates, and decreased contraction and relaxation velocities compared with males. Additionally, males had a shorter overall time from action potential onset to peak contraction. In aggregate, our studies uncovered male and female differences in excitation-contraction coupling that account for differences observed in the EKG. Overall, a better understanding of sex differences in electrophysiology is essential for equitably treating cardiac disease.

Hypothetical interventions and risk of atrial fibrillation by sex and education: application of the parametric g-formula in the Tromsø Study

AIMS

To use the parametric g-formula to estimate the long-term risk of atrial fibrillation (AF) by sex and education under hypothetical interventions on six modifiable risk factors.

METHODS AND RESULTS

We estimated the risk reduction under hypothetical risk reduction strategies for smoking, physical activity, alcohol intake, body mass index, systolic, and diastolic blood pressure in 14 923 women and men (baseline mean age 45.8 years in women and 47.8 years in men) from the population-based Tromsø Study with a maximum of 22 years of follow-up (1994-2016). The estimated risk of AF under no intervention was 6.15% in women and 13.0% in men. This cumulative risk was reduced by 41% (95% confidence interval 17%, 61%) in women and 14% (-7%, 30%) in men under joint interventions on all risk factors. The most effective intervention was lowering body mass index to ≤ 25 kg/m2, leading to a 16% (4%, 25%) lower risk in women and a 14% (6%, 23%) lower risk in men. We found significant sex-differences in the relative risk reduction by sufficient physical activity, leading to a 7% (-4%, 18%) lower risk in women and an 8% (-2%, -13%) increased risk in men. We found no association between the level of education and differences in risk reduction by any of the interventions.

CONCLUSION

The population burden of AF could be reduced by modifying lifestyle risk factors. Namely, these modifications could have prevented 41% of AF cases in women and 14% of AF cases in men in the municipality of Tromsø, Norway during a maximum 22-year follow-up period.

Height Explains Sex Difference in Atrial Fibrillation Risk: Copenhagen General Population Study

OBJECTIVE

To test the hypothesis that the increased risk of atrial fibrillation (AF) in men compared with women is explained by height.

METHODS

From the Copenhagen General Population Study, we included 106,207 individuals (47,153 men and 59,054 women) from 20 to 100 years of age, without a prior diagnosis of AF, examined between November 25, 2003, and April 28, 2015. The main outcome was AF incidence from national hospital registers until April 2018. The association of risk factors with AF incidence was assessed by cause-specific Cox proportional hazards regression and Fine-Gray subdistribution hazards regression analysis.

RESULTS

During a maximum of 14.4 years of follow-up (median, 8.9 years), incident AF was observed in 3449 men and 2772 women with 845 (95% CI, 815 to 875) and 514 (95% CI, 494 to 535) events per 100,000 person-years, respectively. The age-adjusted hazard of incident AF was 63% (95% CI, 55% to 72%) higher in men compared with women. Risk factors for AF were generally similar in men and women, except men were taller than women (179 cm vs 166 cm, respectively; P<.001). When controlling for height, the difference in hazard of incident AF between sexes disappeared. For population attributable risk of AF, height was the most important risk factor investigated and explained 21% and 19% of the risk of incident AF in men and women, respectively.

CONCLUSION

A 63% higher risk of incident AF in men compared with women is explained by differences in height.

Atrial Fibrillation and the Risk of Ventricular Arrhythmias and Cardiac Arrest: A Nationwide Population-Based Study

BACKGROUND

Atrial fibrillation (AF) has been linked to an increased risk of ventricular arrhythmias (VAs) and sudden death. We investigated this association in hospitalised patients in France.

METHODS

All hospitalised patients from 2013 were identified from the French National database and included if they had at least 5 years of follow-up data.

RESULTS

Overall, 3,381,472 patients were identified. After excluding 35,834 with a history of VAs and cardiac arrest, 3,345,638 patients were categorised into two groups: no AF (n = 3,033,412; mean age 57.2 ± 21.4; 54.3% female) and AF (n = 312,226; 78.1 ± 10.6; 44.0% female). Over a median follow-up period of 5.4 years (interquartile range (IQR) 5.0-5.8 years), the incidence (2.23%/year vs. 0.56%/year) and risk (hazard ratio (HR) 3.657 (95% confidence interval (CI) 3.604-3.711)) of VAs and cardiac arrest were significantly higher in AF patients compared to non-AF patients. This was still significant after adjusting for confounders, with a HR of 1.167 (95% CI 1.111-1.226) and in the 1:1 propensity score-matched analysis (n = 289,332 per group), with a HR of 1.339 (95% CI 1.313-1.366). In the mediation analysis, the odds of cardiac arrest were significantly mediated by AF-associated VAs, with an OR of 1.041 (95% CI 1.040-1.042).

CONCLUSION

In hospitalised French patients, AF was associated with an increased risk of VAs and sudden death.

Off-Target Effects of Cancer Therapy on Development of Therapy-Induced Arrhythmia: A Review

BACKGROUND

Advances in cancer therapeutics have improved overall survival and prognosis in this patient population; however, this has come at the expense of cardiotoxicity including arrhythmia.

SUMMARY

Cancer and its therapies are associated with cardiotoxicity via several mechanisms including inflammation, cardiomyopathy, and off-target effects. Among cancer therapies, anthracyclines and tyrosine kinase inhibitors (TKIs) are particularly known for their pro-arrhythmia effects. In addition to cardiomyopathy, anthracyclines may be pro-arrhythmogenic via reactive oxygen species (ROS) generation and altered calcium handling. TKIs may mediate their cardiotoxicity via inhibition of off-target tyrosine kinases. Ibrutinib-mediated inhibition of CSK may be responsible for the increased prevalence of atrial fibrillation. Further investigation is warranted to further elucidate the mechanisms behind arrhythmias in cancer therapies.

KEY MESSAGES

Arrhythmias are a common cardiotoxicity of cancer therapies. Cancer therapies may induce arrhythmias via off-target effects. Understanding the mechanisms underlying arrhythmogenesis associated with cancer therapies may help design cancer therapies that can avoid these toxicities.

Impact of sex on clinical, procedural characteristics and outcomes of catheter ablation for ventricular arrhythmias according to underlying heart disease

BACKGROUND

Women are under-represented in many key studies and trials examining outcomes of catheter ablation (CA) for ventricular arrhythmias (VA). We compared characteristics between men and women undergoing their first catheter ablation for VA at a single centre over 10 years.

METHODS

The clinical, procedural characteristics and outcomes of 287 consecutive patients (male = 182, female = 105), undergoing their first CA at our centre over 10 years were compared according to sex and underlying heart disease.

RESULTS

In the ablation population, women were younger, had fewer co-morbidities, were less likely to have ischemic cardiomyopathy (ICM) and VA storm and were more likely to have idiopathic VA and premature ventricular complexes as the indication for ablation (P < 0.05 for all). Amongst idiopathic and non-ischemic cardiomyopathy (NICM) subgroups, baseline characteristics were similar; amongst ICM, women were younger and had higher numbers of drug failure pre-ablation (P = 0.05). Women were similar to men in all procedural characteristics, acute procedural success and complications, regardless of underlying heart disease. At median follow-up of 666 days, VA-free survival, overall mortality and survival free of death or transplant were comparable in both groups. Sex was not a predictor of these outcomes, after accounting for clinical and procedural characteristics.

CONCLUSION

Women represented 36% of the real-world population at our centre referred for CA of VA. There are key differences in clinical features of women versus men referred for VA ablation. Despite these differences, VA ablation in women can be accomplished with similar success and complication rates to men, regardless of underlying heart disease.

Sex and racial disparities in catheter ablation

Sex and racial disparities in the presentation, diagnosis, and management of cardiac arrhythmias are recognized. Sex-specific differences in electrophysiological parameters are well known and are predominantly related to differences in ion channel expression and the influence of sex hormones. However, the relationship between hormonal or racial influence and arrhythmia mechanisms, presentation, and management needs to be better defined. Women and racial and ethnic groups are less likely to undergo catheter ablation procedures for treatment of cardiac arrhythmias. Underrepresentation of women and racial/ethnic groups in clinical trials has resulted in significant knowledge gaps. Whether sex and racial disparities in arrhythmia management reflect barriers in access to care, physician bias, patient values, and preferences or other factors requires further study.

Visit-to-visit SBP variability and risk of atrial fibrillation in middle-aged and older populations

OBJECTIVE

We sought to examine the relationship between visit-to-visit variability of SBP and incident atrial fibrillation in middle-aged and older population.

METHODS

This prospective cohort study included 26 999 participants aged 50 years or older at study entry. Visit-to-visit variability of SBP was defined as the average real variability (ARV) of three values of SBP from the examinations of 2006, 2008, and 2010. We categorized participants into four groups according to the quartiles of ARV. Incident atrial fibrillation cases were identified via ECG during biennial resurveys, and reviewing medical insurance record and discharge registers. We used Cox regression models to evaluate the hazard ratios and 95% confidence intervals (CI) for incident atrial fibrillation.

RESULTS

After an average follow-up of 9.24 years, a total of 420 atrial fibrillation cases were identified. The incidence of atrial fibrillation from the lowest to the highest quartiles of SBP variability were 1.23, 1.53, 1.81 and 2.19 per 1000 person-years, respectively. After adjusting for potential confounders, including mean blood pressure, we found a graded association between SBP variability and risk of atrial fibrillation. Participants in the third quartile and the highest quartile were associated with 35 and 53% higher risk of developing atrial fibrillation, respectively, compared with participants in the lowest quartile [hazard ratio (95% CI), 1.35 (1.01-1.82) and 1.53 (1.15-2.04)]. The results persisted across sensitivity analyses.

CONCLUSION

Increased visit-to-visit variability of SBP is a strong predictor of incident atrial fibrillation in middle-aged and older population. Evaluation of long-term SBP variability could help to identify individuals at higher risk of atrial fibrillation.

Sex Differences in Atrial Fibrillation Risk: The VITAL Rhythm Study

Importance

Women have a lower incidence of atrial fibrillation (AF) compared with men in several studies, but it is unclear whether this sex difference is independent of sex differences in prevalent cardiovascular disease (CVD), body size, and other risk factors.

Objective

To examine sex differences in AF incidence and whether AF risk factors differ by sex in a contemporary cohort of men and women without prevalent CVD.

Design, Setting, and Participants

This was a prospective cohort analysis within the Vitamin D and Omega-3 Trial (VITAL) Rhythm Study, a randomized trial that examined the effect of vitamin D and ω-3 fatty acid supplementation on incident AF among men 50 years or older and women 55 years or older without a prior history of prevalent AF, CVD, or cancer at baseline. Data were analyzed from September 29, 2020, to June 29, 2021.

Exposures

Sex, height, weight, body mass index (BMI), body surface area (BSA), and other AF risk factors at study enrollment.

Main Outcomes and Measures

Incident AF confirmed by medical record review.

Results

A total of 25 119 individuals (mean [SD] age, 67.0 [7.1] years; 12 757 women [51%]) were included in this study. Over a median (IQR) follow-up of 5.3 (5.1-5.7) years, 900 confirmed incident AF events occurred among 12 362 men (495 events, 4.0%) and 12 757 women (405 events, 3.2%). After adjustment for age and treatment assignment, women were at lower risk for incident AF than men (hazard ratio [HR], 0.68; 95% CI, 0.59-0.77; P < .001). The inverse association between female sex and AF persisted after adjustment for race and ethnicity, smoking, alcohol intake, hypertension, diabetes (type 1, type 2, gestational), thyroid disease, exercise, and BMI (HR, 0.73; 95% CI, 0.63-0.85; P <.001). However, female sex was positively associated with AF when height (HR, 1.39; 95% CI, 1.14-1.72; P = .001), height and weight (HR 1.49, 95% CI, 1.21-1.82; P <.001), or BSA (HR, 1.25; 95% CI, 1.06-1.49; P = .009) were substituted for BMI in the multivariate model. In stratified models, risk factor associations with incident AF were similar for women and men.

Conclusions and Relevance

In this cohort study, findings suggest that after controlling for height and/or body size, women without CVD at baseline were at higher risk for AF than men, suggesting that sex differences in body size account for much of the protective association between female sex and AF. These data underscore the importance of AF prevention in women.

Sex differences in presentation of atrial fibrillation: Findings from 30-day ambulatory monitoring in real-world practice

Background

Women are less likely to receive oral anticoagulation or ablation for treatment of atrial fibrillation (AF). Identification of sex differences in arrhythmia characteristics and symptoms may lead to a better understanding of potential reasons for these differences.

Objectives

To determine sex differences in AF with respect to heart rate, duration, burden, and symptoms in patients undergoing mobile cardiac telemetry (MCT) monitoring.

Methods

All patients who registered for ≤30-day MCT using PocketECG (MediLynx) in the USA in 2017 were included (n = 27,512, 58 % women). PocketECG records and transmits a three-lead ambulatory electrocardiogram (ECG) with real-time beat-to-beat analysis. Sex-related differences were analyzed with Chi2 and Spearmans rho.

Results

Fewer women than men were diagnosed with AF lasting ≥30s (13.7 % versus [vs] 19.0 %, p < 0.001). AF burden was lower in women in all age groups <90 years (all p < 0.01). Women were older at the time of AF diagnosis (median 76 vs 73 years, p < 0.001), had faster heart rate during AF (mean: 104.7 ± 26.0 vs 96.7 ± 26.7 bpm, p < 0.001), and shorter AF duration (mean: 96.2 ± 176.0 vs 121.6 ± 189.9 min, p < 0.001). There was a non-significant trend toward more symptoms (such as dizziness, racing heart, fatigue, or palpitations) during AF in women compared to men (46.5 % vs 43.7 %, p = 0.062).

Conclusions

AF was less prevalent and occurred at lower burdens in women than men in each age strata. Despite faster heart rates in AF in women, there were no significant sex differences in reported symptoms during AF. Sex differences in therapy cannot be explained by differences in symptoms or rates in AF.

Condensed abstract

Real-world data on sex differences in AF using a 30-day MCT monitoring device remain scarce. We aim to determine the sex differences in AF with respect to prevalence, burden, heart rate, and symptom in patients undergoing ≤30-day MCT monitoring. Our data analysis suggests that fewer women than men had AF, women were older at diagnosis of AF, and women with AF had higher mean heart rate, shorter mean AF duration, and lower mean AF burden than men. Further studies are needed to examine reasons for sex differences, specifically in relation to AF therapy and its impact on clinical outcomes.

Sex differences in arterial hypertension

There is strong evidence that sex chromosomes and sex hormones influence blood pressure (BP) regulation, distribution of cardiovascular (CV) risk factors and co-morbidities differentially in females and males with essential arterial hypertension. The risk for CV disease increases at a lower BP level in females than in males, suggesting that sex-specific thresholds for diagnosis of hypertension may be reasonable. However, due to paucity of data, in particularly from specifically designed clinical trials, it is not yet known whether hypertension should be differently managed in females and males, including treatment goals and choice and dosages of antihypertensive drugs. Accordingly, this consensus document was conceived to provide a comprehensive overview of current knowledge on sex differences in essential hypertension including BP development over the life course, development of hypertension, pathophysiologic mechanisms regulating BP, interaction of BP with CV risk factors and co-morbidities, hypertension-mediated organ damage in the heart and the arteries, impact on incident CV disease, and differences in the effect of antihypertensive treatment. The consensus document also highlights areas where focused research is needed to advance sex-specific prevention and management of hypertension.

Sex and ethnicity modified high 1-year mortality in patients in Singapore with newly diagnosed atrial fibrillation

INTRODUCTION

We investigated sex and ethnic differences in the incidence, clinical characteristics and 1-year mortality of patients with newly diagnosed AF in a multi-ethnic population.

METHOD

This retrospective cohort study of patients diagnosed with AF from 2008 to 2015 was based on medical claims, casemix and subvention data submitted to the Ministry of Health. Patients with AF were matched with controls without AF for age (3-year bands), sex and ethnicity, and categorised as middle-aged (45-64 years) or elderly (≥65 years) among major ethnic groups in Singapore (Chinese, Malay and Indian).

RESULTS

Among 40,602 adults with AF (elderly 74%), Malays had the highest age-standardised incidence rate of AF, followed by Chinese and Indians; and the rate was higher in men. Despite having the worst cardiovascular risk profile, Indians had the lowest prevalence and incidence of AF. The 1-year mortality rate after newly diagnosed AF was 22-26 deaths per 100 people. Newly diagnosed AF was independently associated with increased 1-year all-cause mortality among middle-aged (adjusted odds ratio [AOR] 9.08, 95% confidence interval [CI] 7.36-11.20) and elderly adults (AOR 3.60, 95% CI 3.40-3.80) compared with those without AF. Sex differences in mortality among patients with AF were limited to elderly adults (men: AOR 1.17, 95% CI 1.11-1.24), while Indians were associated with a 30% increased odds of mortality compared with Chinese regardless of age (middle-aged: AOR 1.27, 95% CI 1.09-1.548 elderly: AOR 1.33, 95% CI 1.22-1.45).

CONCLUSION

Variations in incidence, clinical profile and 1-year mortality of patients with AF in a nationwide cohort were influenced by sex and ethnicity. Newly diagnosed AF portends a worse prognosis and is a marker of high mortality within the first year.

Application of plasma metabolome for monitoring the effect of rivaroxaban in patients with nonvalvular atrial fibrillation

Rivaroxaban, an oral factor Xa inhibitor, has been used to treating a series of thromboembolic disorders in clinical practice. Measurement of the anticoagulant effect of rivaroxaban is important to avoid serious bleeding events, thus ensuring the safety and efficacy of drug administration. Metabolomics could help to predict differences in the responses among patients by profiling metabolites in biosamples. In this study, plasma metabolomes before and 3 hours after rivaroxaban intake in 150 nonvalvular atrial fibrillation (NVAF) patients and 100 age/gender-matched controls were analyzed by liquid chromatography coupled with mass spectrometry (LC-MS/MS). When compared with controls, a total of thirteen plasma metabolites were differentially expressed in the NVAF patients. Pathway analysis revealed that purine and lipid metabolism were dysregulated. A panel of three metabolites (17a-ethynylestradiol, tryptophyl-glutamate and adenosine) showed good predictive ability to distinguish nonvalvular atrial fibrillation with an area under the receiver operating characteristic curve (AUC) of 1 for the discovery phase and 1 for validation. Under rivaroxaban treatment, a total of seven metabolites changed, the lipid and glycosylphosphatidylinositol biosynthesis pathways were altered and the panel consisting of avocadene, prenyl glucoside and phosphatidylethanolamine showed predictive ability with an AUC of 0.86 for the discovery dataset and 0.82 for the validation. The study showed that plasma metabolomic analyses hold the potential to differentiate nonvalvular atrial fibrillation and can help to monitor the effect of rivaroxaban anticoagulation.

Association of Coffee Consumption With Atrial Fibrillation Risk: An Updated Dose–Response Meta-Analysis of Prospective Studies

Background

Several published studies have examined the association of coffee consumption with atrial fibrillation (AF) risk, but their findings are still controversial. Therefore, we performed a systematic review and dose–response meta-analysis of prospective studies to determine the relationship between coffee consumption and the risk of incident AF.

Methods

We systematically retrieved the PubMed and Embase databases until October 2021 for pertinent studies that reported the association of coffee consumption (caffeinated or decaffeinated coffee) with AF risk. A cubic spline random-effects model was used to fit the potential dose–response curve. The effect estimates were expressed as adjusted risk ratios (RRs) and 95% CIs.

Results

A total of 10 prospective studies (11 cohorts) involving 30,169 AF events and 723,825 participants were included. In the dose–response analysis, there was a linear inverse association between coffee intake and risk of AF although not statistically significant (P_{non–linearity} = 0.25). Compared with participants with no coffee consumption, the RRs (95% CI) of AF risk estimated directly from the dose–response curve were 1.01 (0.98–1.03), 1.00 (0.97–1.04), 0.99 (0.92–1.02), 0.95 (0.89–1.01), 0.94 (0.87–1.01), 0.89 (0.79–1.02), and 0.87 (0.76–1.02) for 1–7 cups of coffee per day, respectively. One cup per day increased in coffee consumption was associated with a 2% reduced risk of AF (RR = 0.98, 95% CI: 0.97–1.00, P = 0.02).

Conclusions

Our evidence from this meta-analysis suggested that coffee consumption had a trend toward reducing the risk of AF in a dose–response manner. Further studies could be conducted to reinforce our findings.

Sex Differences and Temporal Trends in Hospitalization for Catheter Ablation of Nonvalvular Atrial Fibrillation: A Single-Center Experience for 15 Years

Background

There exist sex differences in the clinical profile, management, and outcome of atrial fibrillation (AF). Catheter ablation of AF has become a first-line therapy and has markedly made headway over the recent decades. Little is known about sex differences and temporal trends in hospitalization for catheter ablation of AF in the real-world setting.

Methods

We retrospectively retrieved medical records of patients at Beijing Anzhen Hospital between January 2005 and December 2019. The patients undergoing catheter ablation of AF were enrolled. Demographical and clinical data were compared between sexes. The temporal trends of sex differences were evaluated.

Results

We identified 13502 male patients (66.8%) and 6713 female patients (33.2%). The number of patients undergoing AF ablation had remarkably increased over time, but no sex differences were observed (p=0.17). The median age of women was five years older than that of men (p < 0.001). The median time of in-hospital stay for the women decreased from 11 days to 4 days and for the men from 9 to 4 days. In-hospital mortality was 0.03% and 0.01% for women and men, respectively, with no significant difference between sexes. The women were more likely to have a comorbid diagnosis of hypertension and heart failure than men (p < 0.001). The CHA₂DS₂-VA score was higher in women than in men (1.64 vs. 1.28, p < 0.001). The temporal trend in the score increased in women from 1.17 to 1.81 (p < 0.001) and in men from 0.91 to 1.41 (p < 0.001). The percentage of patients with CHA₂DS₂-VA score ≥2 was higher in women than in men (49.8% vs. 35.8%, p < 0.001), and the temporal trend of this sex gap was nearly doubled (8.0% in 2005–2007 vs. 15.5% in 2017–2019, p=0.03).

Conclusions

Safety of catheter ablation for AF was comparable in both sexes. In contrast, the women showed a higher CHA₂DS₂-VA score than men. The percentage of patients with CHA₂DS₂-VA score ≥2 increased more quickly in women than in men. Furthermore, sex-specific research is warranted to reduce this sex disparity.

Effect of Sacubitril/Valsartan on Reducing the Risk of Arrhythmia: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background and Objective

Relevant data of PARADIGM-HF reveals sacubitril/valsartan (SV) therapy led to a greater reduction in the risks of arrhythmia, and sudden cardiac death than angiotensin converting enzyme inhibitor (ACEI)/angiotensin receptor inhibitor (ARB) therapy in HFrEF, however, inconsistent results were reported in subsequent studies. Here, we conduct a meta-analysis of related randomized controlled trials (RCTs) to evaluate the protective effect of SV on reducing the risk of arrhythmias.

Methods and Results

RCTs focused on the difference in therapeutic outcomes between SV and ACEI/ARB were searched from PUBMED, EMBASE, ClinicalTrials.gov, and Cochrane Library. The results were extracted from each individual study, expressed as binary risk, 95% confidence interval (CI) and relative risk (RR). Sixteen RCTs including 22, 563 patients met the study criteria. Compared with ACEI/ARB therapy, SV therapy did significantly reduce in the risks of severe arrhythmias among patients with heart failure with reduced ejection fraction (HFrEF) (RR 0.83, 95% CI 0.73–0.95, p = 0.006), ventricular tachycardia (VT) among patients with HFrEF (RR 0.69, 95% CI 0.51–0.92, p = 0.01), cardiac arrest among patients with heart failure (HF) (RR 0.52, 95% CI 0.37–0.73, p = 0.0002), cardiac arrest among patients with HFrEF (RR 0.49, 95% CI 0.32–0.76, p = 0.001), cardiac arrest or ventricular fibrillation (VF) among patients with HF (RR 0.63, 95% CI 0.48–0.83, p = 0.001), and cardiac arrest or VF among patients with HFrEF (RR 0.65, 95% CI 0.47–0.89, p = 0.008), but reduced the risks of arrhythmias (RR 0.87, 95% CI 0.74–1.01, p = 0.07), atrial arrhythmias (RR 0.98, 95% CI 0.83–1.16, p = 0.85), and atrial fibrillation (RR 0.98, 95% CI 0.82–1.17, p = 0.82) among all patients with no significant between-group difference. The merged result was robust after sensitivity analysis, and there was no publication bias.

Conclusion

Our meta-analysis provides evidence that, compared with ACEI/ARB, SV can additionally reduce the risks of most arrhythmias, just the significant differences are revealed in reducing the risks of VT, severe arrhythmias, and cardiac arrest in patients with HFrEF. Besides, the positive effect of SV on VF according to statistical result of combining VF with cardiac arrest in patients with HFrEF is credibility.

Changes in the prevalence of atrial fibrillation in the Russian population over a 13-year follow-up

Aim. To study the prevalence of atrial fibrillation (AF) in the Russian urban population cohort aged 45-69 years and its changes over 13-year follow-up during aging.

Material and methods. This cross-sectional long-term prospective study included random population sample of men and women 45-69 years (n=9360, HAPIEE project, Novosibirsk), which was examined in 2003-2005 and was re-examined twice and followed up for about 13±1,00 years in men and 13,1±2,17 years in women. The incidence of AF was assessed for individuals without AF or cardiovascular disease (CVD) at the baseline examination. Statistical analysis was performed using the SPSS software package (v.13.0).

Results. In a population sample over a 13-year follow-up, AF prevalence increased from 1,6% (1,1% among women and 2,1% among men) at the age of 45-69 years to 4,2% (3,0% among women and 6,1% among men) aged 55-84 years according to screening rest ECG examinations. The prevalence of new AF cases over a 13-year followup in the cohort of 45-69 years old without previous CVD and AF was 5,6%, of which 40% were paroxysmal. The mean age at the time of first registered AF was 69±6,93 years, and was 2 years higher in women (70,0±6,83) than in men (68±6,93). The average period before the AF onset among people aged 45-69 years without baseline CVD and AF was 7,5±3,83 years for men and 8,1±4,02 years for women. The total prevalence of AF in the population sample was 8,3%. The highest AF prevalence was registered at the age of 65-69 years (11,4%) for men and 5 years later for women (12,0%) (p80 years decreased and amounted to 4,1% among men and 5,7% among women.

Conclusion. In the Russian population sample (Novosibirsk) aged 45-69, the AF prevalence increased from 1,6 to 8,3% over 13 years of follow-up. In addition, 473 new AF cases were identified, ~40% of which were paroxysmal AF. The prevalence of AF in the Siberian population sample for the 45-60 years age group is comparable with the large Russian and North American studies, but higher for persons aged 60-74 years and lower for older age group, for both men and women.

Research Opportunities in Autonomic Neural Mechanisms of Cardiopulmonary Regulation: A Report From the National Heart, Lung, and Blood Institute and the National Institutes of Health Office of the Director Workshop

This virtual workshop was convened by the National Heart, Lung, and Blood Institute, in partnership with the Office of Strategic Coordination of the Office of the National Institutes of Health Director, and held September 2 to 3, 2020. The intent was to assemble a multidisciplinary group of experts in basic, translational, and clinical research in neuroscience and cardiopulmonary disorders to identify knowledge gaps, guide future research efforts, and foster multidisciplinary collaborations pertaining to autonomic neural mechanisms of cardiopulmonary regulation. The group critically evaluated the current state of knowledge of the roles that the autonomic nervous system plays in regulation of cardiopulmonary function in health and in pathophysiology of arrhythmias, heart failure, sleep and circadian dysfunction, and breathing disorders. Opportunities to leverage the Common Fund's SPARC (Stimulating Peripheral Activity to Relieve Conditions) program were characterized as related to nonpharmacologic neuromodulation and device-based therapies. Common themes discussed include knowledge gaps, research priorities, and approaches to develop novel predictive markers of autonomic dysfunction. Approaches to precisely target neural pathophysiological mechanisms to herald new therapies for arrhythmias, heart failure, sleep and circadian rhythm physiology, and breathing disorders were also detailed.

Rhythm control versus rate control in a contemporary ambulatory atrial fibrillation cohort: Post-hoc analysis of the IMPACT-AF Trial

Background

We examined the characteristics and outcomes in a contemporary ambulatory population of patients with atrial fibrillation (AF), comparing rate control with rhythm control.

Methods

This is a post hoc analysis of a cluster-randomized trial (Integrated Management Program Advancing Community Treatment of Atrial Fibrillation [IMPACT-AF]) in ambulatory AF patients from 2016 to 2018, which compared use of a clinical decision support tool for general practitioners to usual care. This analysis compared patients managed with rate vs rhythm control, at entry into the study. Outcomes included AF-related emergency department (ED) visits, unplanned cardiovascular hospitalizations, and bleeding events at 12 months.

Results

A total of 870 patients were included in this analysis, 99 (11.4%) in the rhythm-control group, and 40% women. In the rhythm-control group, the mean age was younger (70 ± 11.4 vs 72.7 ± 9.5 years, P = 0.03), a higher number were paroxysmal (80% vs 43%, P < 0.001), and CHADS₂ scores were lower. The rate of AF-related ED visits was higher in the rhythm-control group (17.2 vs 7.3%, P = 0.003), and repeat visits (rate ratio 3.03, 95% confidence interval [1.99-4.52], P < 0.001). The number of repeat ED visits was independently associated with female sex and being in the rhythm-control group.

Conclusions

Both rate- and rhythm-control patients have recurrent ED visits, with a higher rate in patients treated with rhythm control. These findings are observational, but taken in the context of current guidelines could help develop further therapies aimed at improving symptom burden in both rhythm- and rate-control patients to broadly improve healthcare utilization in the AF population.

The Determinants of the 13-Year Risk of Incident Atrial Fibrillation in a Russian Population Cohort of Middle and Elderly Age

Atrial fibrillation (AF) is the most common arrhythmia and a predictor of the complications of atherosclerotic cardiovascular diseases (ASCVDs), particularly thromboembolic events and the progression of heart failure. We analyzed the determinants of the 13-year risk of incident AF in a Russian population cohort of middle and elderly age. A random population sample (n = 9360, age 45–69 years) was examined at baseline in 2003–2005 and reexamined in 2006–2008 and 2015–2017 in Novosibirsk (the HAPIEE study). Incident AF was being registered during the average follow-up of 13 years. The final analysis included 3871 participants free from baseline AF and cardiovascular disease (CVD) who participated in all three data collections. In a multivariable-adjusted Cox regression model, the 13-year risk of AF was positively associated with the male sex (hazard ratio (HR) = 2.20; 95% confidence interval (CI) 1.26–3.87); age (HR = 1.10 per year; 95% CI 1.07–1.14); body mass index (BMI), (HR = 1.11 per unit; 95% CI 1.07–1.15); systolic blood pressure (SBP), (HR = 1.02 per 1 mmHg; 95% CI 1.01–1.02), and it was negatively associated with total cholesterol (TC), (HR = 0.79 per 1 mmol/L; 95% CI 0.66–0.94). In women, the risk of AF was more strongly associated with hypertension (HT) and was also negatively related to total cholesterol (TC) level (HR = 0.74 per 1 mmol/L; 95% CI 0.56–0.96). No independent association was found with mean alcohol intake per drinking occasion. These results in a Russian cohort have an implication for the prediction of AF and ASCVD complications in the general population.

Incidence of Arrhythmias and Their Prognostic Value in Patients With Multiple Myeloma

Background: Arrhythmias are common cardiovascular complications in multiple myeloma (MM) patients and are related to a poor prognosis.

Objective: This study aimed to assess the burden of arrhythmias and their prognostic value in patients with MM.

Methods: This was a retrospective study of patients with MM between January 2015 and April 2020 at the First Affiliated Hospital of Xi'an Jiaotong University. The incidence of arrhythmia and associated risk factors were evaluated. The relationship between the type of arrhythmia and survival was analyzed.

Results: A total of 319 patients with MM were identified, and 48.0% (153/319) had arrhythmias. The most common type of arrhythmia was sinus tachycardia (ST) (15.0%, 48/319), followed by sinus bradycardia (SB) (14.4%, 46/319), premature atrial contractions (PACs) (6.3%, 20/319), conduction disorders (CDs) (6.0%, 19/319), atrial fibrillation (AF) (6.0%, 19/319), premature ventricular contractions (PVCs) (4.4%, 14/319) and paroxysmal supraventricular tachycardia (PSVT) (0.6%, 2/319). The patients with arrhythmias had higher levels of log NT-proBNP and creatinine, greater bortezomib use, and a higher incidence of diabetes than those without arrhythmias (P < 0.05). The all-cause mortality rates of patients without arrhythmias and those with AF, ST, PACs, CDs, SB, and PVCs were 50.6% (84/166), 73.7% (14/19), 60.4% (29/48), 60.0% (12/20), 52.6% (10/19), 34.8% (16/46), and 28.6% (4/14), respectively. In a subgroup analysis of patients experiencing different types of arrhythmias, patients with SB had lower all-cause mortality than patients with AF (P < 0.01). Univariate and multivariate Cox analyses showed that there was a positive statistically significant association between SB and survival (HR: 0.592 [0.352–0.998], P = 0.049) in a subgroup analysis of different arrhythmias.

Conclusions: Patients with MM had a heavy arrhythmia burden, and in this study, approximately half of MM patients had arrhythmias. MM patients with SB were associated with lower all-cause mortality than those with AF. SB might be an independent positive factor for prognosis.

Sex Differences in Heart Failure

Heart failure (HF) continues to be a major contributor of morbidity and mortality for men and women alike, yet how the predisposition for, course and management of HF differ between men and women remains underexplored. Sex differences in traditional risk factors as well as sex-specific risk factors influence the prevalence and manifestation of HF in unique ways. The pathophysiology of HF differs between men and women and may explain sex-specific differences in clinical presentation and diagnosis. This in turn contributes to variation in response to both pharmacologic and device/surgical therapy. This review examines sex-specific differences in HF spanning prevalence, risk factors, pathophysiology, presentation, and therapies with a specific focus on highlighting gaps in knowledge with calls to action for future research efforts.

The impact of height on recurrence after index catheter ablation of paroxysmal atrial fibrillation

PURPOSE

The relationship between height and incident atrial fibrillation (AF) has recently been demonstrated. We aimed to evaluate the impact of height on outcomes of ablation in patients with drug-refractory symptomatic paroxysmal AF (PAF).

METHODS

A total of 689 patients (470 males; age, 53.0 ± 11.7 years) with symptomatic paroxysmal AF receiving index catheter ablation (CA) between 2003 and 2013 were enrolled in this study. The baseline characteristics, ablation, and follow-up results were evaluated. The patients were categorized according to the quartiles of height for each sex.

RESULTS

Patients in the lower quartiles of height had a lower incidence of AF recurrence (log-rank p = 0.022). Height in female patients was strongly associated with AF recurrence (p = 0.027) after an index ablation in the 6.33 ± 4.32 years of follow-up. Female patients > 159 cm in height had a higher likelihood of AF recurrence after index CA (HR = 2.01, 95% CI: 1.24-3.25, p = 0.005) than that in those below this height. In computed tomography (CT) scan, the superoinferior diameter of the left atrium (LA) correlated with body height in females, but not in male patients.

CONCLUSIONS

Height is associated with AF recurrence after the index CA of PAF in female patients. In Asian populations, women above height 159 cm are twice as likely to have AF recurrence post-ablation as shorter women.

Sudden cardiac death among Iranian population: a two decades follow-up of Tehran lipid and glucose study

Sudden cardiac death (SCD) is described as death within one hour, if observed, from the onset of symptoms, and within 24 h of being alive and well if not observe. Study population includes 3705 men and 4446 women, aged ≥ 30 years. Multivariable Cox proportional hazard models were used to determine the risk factors associated with SCD. After a median follow-up of 17.9 years, 244 SCD (165 in males) occurred. The age-standardized incidence rate (95% confidence intervals (CI)) of SCD was 2.3 (2.1–2.7) per 1000 person-year. Current smoking [Hazard ratio (HR): 2.43, 95% CI: 1.73–3.42], high waist circumference [1.49: 1.04–2.12], hypertension [1.39: 1.05–1.84], type 2 diabetes mellitus [2.78: 2.09–3.69], pulse rate ≥ 90 beats per/minute [1.72: 1.22–2.42] and prevalent cardiovascular disease [1.75: 1.26–2.45] were significant risk factors. The corresponding population attributed fractions (PAF) were 14.30, 16.58, 14.03, 19.60, 7.62, and 8.30, respectively. Being overweight [0.58: 0.40–0.83] and obese [0.61: 0.38–0.98] decreased the risk of SCD. After excluding known diabetes cases from our data analysis, the newly diagnosed diabetes still showed an HR of 2.0 (1.32–3.00) with a PAF of 7.15% in the full adjustment model. To deal with sudden death as a catastrophic outcome, multi-component strategies by policy health makers are suggested.

Sex and Heart Failure Treatment Prescription and Adherence

Heart disease is the leading cause of death in both men and women in developed countries. Heart failure (HF) contributes to significant morbidity and mortality and continues to remain on the rise. While advances in pharmacological therapies have improved its prognosis, there remain a number of unanswered questions regarding the impact of these therapies in women. Current HF guidelines recommend up-titration of neurohormonal blockade, to the same target doses in both men and women but several factors may impair achieving this goal in women: more adverse drug reactions, reduced adherence and even lack of evidence on the optimal drug dose. Systematic under-representation of women in cardiovascular drug trials hinders the identification of sex differences in the efficacy and safety of cardiovascular medications. Women are also under-represented in device therapy trials and are 30% less likely to receive a device in clinical practice. Despite presenting with fewer ventricular arrythmias and having an increased risk of implant complications, women show better response to resynchronization therapy, with lower mortality and HF hospitalizations. Fewer women receive advanced HF therapies. They have a better post-heart transplant survival compared to men, but an increased immunological risk needs to be acknowledged. Technological advances in mechanical circulatory support, with smaller and more hemocompatible devices, will likely increase their implantation in women. This review outlines current evidence regarding sex-related differences in prescription, adherence, adverse events, and prognostic impact of the main management strategies for HF.

Ischemic Etiology and Prognosis in Men and Women with Acute Heart Failure

Coronary heart disease is common in heart failure (HF). Our aim was to determine the impact of ischemic etiology on prognosis among men and women with HF. This study is a prospective national multicenter registry. The primary endpoint was 12-month mortality. Patients with HF and ischemic heart disease were stratified according to sex. A total of 1830 patients were enrolled of which 756 (41.3%) were women. Ischemic etiology was more common in men (446 (41.6%)) than in women (167 (22.2%)). Among patients with ischemic HF, diabetes was more frequent in women than in men. Ischemic etiology was not associated with higher mortality risk, and this was true for women (Hazard Ratio [HR] 1.51, 95% Confidence Interval [CI] 0.98–2.32; p = 0.61) and men (HR 1.14, 95% CI 0.81–1.61; p = 0.46), p-value for interaction: 0.067. Mortality/readmission risk in ischemic HF increased in men with previous readmissions (HR 1.15, 95% CI 1.02–1.29; p = 0.022), chronic obstructive pulmonary disease (HR1.20, 95% CI 1.02–1.41; p = 0.026) and in women with diabetes (HR 2.23, 95% CI 1.05–4.47; p = 0.035). Ischemic etiology was not associated with mortality in HF patients. In ischemic HF, the variables associated with a poor prognosis were diabetes in women and previous readmissions and chronic obstructive pulmonary disease in men.

Sex-Specific Associations between Blood Pressure and Risk of Atrial Fibrillation Subtypes in the Tromsø Study

The aim of this study was to explore sex-specific associations between systolic blood pressure (SBP), hypertension, and the risk of incident atrial fibrillation (AF) subtypes, including paroxysmal, persistent, and permanent AF, in a general population. A total of 13,137 women and 11,667 men who participated in the fourth survey of the Tromsø Study (1994–1995) were followed up for incident AF until the end of 2016. Cox proportional hazards regression analysis was conducted using fractional polynomials for SBP to provide sex- and AF-subtype-specific hazard ratios (HRs) for SBP. An SBP of 120 mmHg was used as the reference. Models were adjusted for other cardiovascular risk factors. Over a mean follow-up of 17.6 ± 6.6 years, incident AF occurred in 914 (7.0%) women (501 with paroxysmal/persistent AF and 413 with permanent AF) and 1104 (9.5%) men (606 with paroxysmal/persistent AF and 498 with permanent AF). In women, an SBP of 180 mmHg was associated with an HR of 2.10 (95% confidence interval [CI] 1.60–2.76) for paroxysmal/persistent AF and an HR of 1.80 (95% CI 1.33–2.44) for permanent AF. In men, an SBP of 180 mmHg was associated with an HR of 1.90 (95% CI 1.46–2.46) for paroxysmal/persistent AF, while there was no association with the risk of permanent AF. In conclusion, increasing SBP was associated with an increased risk of both paroxysmal/persistent AF and permanent AF in women, but only paroxysmal/persistent AF in men. Our findings highlight the importance of sex-specific risk stratification and optimizing blood pressure management for the prevention of AF subtypes in clinical practice.

Sex differences in arrhythmic burden with the wearable cardioverter-defibrillator

BACKGROUND

Data on the arrhythmic burden of women at risk for sudden cardiac death are limited, especially in patients using the wearable cardioverter-defibrillator (WCD).

OBJECTIVE

We aimed to characterize WCD compliance, atrial and ventricular arrhythmic burden, and WCD outcomes by sex in patients enrolled in the Prospective Registry of Patients Using the Wearable Cardioverter Defibrillator (WEARIT-II U.S. Registry).

METHODS

In the WEARIT-II Registry, we stratified 2000 patients by sex into women (n = 598) and men (n = 1402). WCD wear time, ventricular and atrial arrhythmic events during WCD use, and implantable cardioverter-defibrillator (ICD) implantation rates at the end of WCD use were evaluated.

RESULTS

The mean WCD wear time was similar in women and men (94 days vs 90 days; P = .145), with longer daily use in women (21.4 h/d vs 20.7 h/d; P = .001). Burden of ventricular tachycardia or ventricular fibrillation was higher in women, with 30 events per 100 patient-years compared with 18 events per 100 patient-years in men (P = .017), with similar findings for treated and non-treated ventricular tachycardia/ventricular fibrillation. Recurrent atrial arrhythmias/sustained ventricular tachycardia was also more frequent in women than in men (167 events per 100 patient-years vs 73 events per 100 patient-years; P = .042). However, ICD implantation rate at the end of WCD use was similar in both women and men (41% vs 39%; P = .448).

CONCLUSION

In the WEARIT-II Registry, we have shown a higher burden of ventricular and atrial arrhythmic events in women than in men. ICD implantation rates at the end of WCD use were similar. Our findings warrant monitoring women at risk for sudden cardiac death who have a high burden of atrial and ventricular arrhythmias while using the WCD.

Does Sex Modify an Association of Electrophysiological Substrate with Sudden Cardiac Death? The Atherosclerosis Risk in Communities (ARIC) Study

Background

Sex is a well-recognized risk factor for sudden cardiac death (SCD). We hypothesized that sex modifies the association of electrophysiological (EP) substrate with SCD.

Objective

The purpose of this study was to determine whether there are sex differences in electrocardiographic (ECG) measures and whether sex modifies the association of ECG measures of EP substrate with SCD.

Methods

Participants from the Atherosclerosis Risk in Communities study with analyzable ECGs (n = 14,725; age 54.2 ± 5.8 years; 55% female; 74% white) were included. EP substrate was characterized by heart rate, QRS, QTc, Cornell voltage, spatial ventricular gradient (SVG), and sum absolute QRST integral (SAI QRST) ECG metrics. Two competing outcomes were adjudicated: SCD and non-SCD. Interaction of ECG metrics with sex was studied in Cox proportional hazards and Fine-Gray competing risk models. Model 1 was adjusted for prevalent cardiovascular disease (CVD) and risk factors. Time-updated model 2 was additionally adjusted for incident nonfatal CVD. Relative hazard ratio (RHR) and relative subhazard ratio with 95% confidence interval (CI) for SCD and non-SCD risk for women relative to men were calculated. Model 1 was adjusted for prevalent CVD and risk factors. Time-updated model 2 was additionally adjusted for incident nonfatal CVD.

Results

Over median follow-up of 24.4 years, there were 530 SCDs (incidence 1.72; 95% CI 1.58–1.88 per 1000 person-years). Women compared to men experienced a greater risk of SCD associated with Cornell voltage (RHR 1.18; 95% CI 1.06–1.32; P = .003), SAI QRST (RHR 1.16; 95% CI 1.04–1.30; P = .007), and SVG magnitude (RHR 1.24; 95% CI 1.05–1.45; P = .009), independently from incident CVD.

Conclusion

In women, the global EP substrate is associated with up to 24% greater risk of SCD than in men, suggesting differences in underlying mechanisms and the need for sex-specific SCD risk stratification.

Anticoagulation Therapy in Patients with Non-valvular Atrial Fibrillation in a Private Setting in Brazil: A Real-World Study

Fundamento:

A segurança e a eficácia da varfarina dependem da qualidade do controle da anticoagulação. Estudos observacionais associam controle deficiente com aumento de morbidade, mortalidade e custos com saúde.

Objetivos:

Desenvolver um perfil de pacientes com fibrilação atrial não valvar (FANV) tratados com varfarina em ambiente ambulatorial e hospitalar privado brasileiro, avaliar a qualidade do controle da anticoagulação e sua associação com resultados clínicos e econômicos.

Métodos:

Este estudo retrospectivo, por meio de um conjunto de dados de seguros privados de saúde no Brasil, identificou pacientes com FANV tratados com varfarina entre 01 de maio de 2014 a 30 de abril de 2016, descreveu seu manejo da anticoagulação e quantificou os custos relacionados à doença. Foram recuperados dados demográficos, histórico clínico, medicação concomitante e tempo na faixa terapêutica (TTR) dos valores da razão normalizada internacional (RNI). Os pacientes foram agrupados em quartis de TTR, com um bom controle sendo definido como TTR ≥65% (método de Rosendaal). Sangramentos maiores e custos médicos diretos por todas as causas foram calculados e comparados entre subgrupos de controle bons e ruins. Valores de p < 0,05 foram considerados estatisticamente significantes.

Resultados:

A análise incluiu 1220 pacientes (mediana de seguimento: 1,5 anos; IIQ: 0,5–2,0). Em média, cada paciente recebeu 0,95 medidas mensais de RNI (RNI média: 2,60 ± 0,88, com 26,1% dos valores < 2 e 24,8% > 3), (mediana de TTR: 58%; IIQ: 47-68%), (TTR médio: 56,6% ± 18,9%). Apenas 31% dos pacientes estavam bem controlados (TTR médio: 78% ± 10%), com 1,6% apresentando grandes sangramentos na mediana do seguimento e custos médicos diretos por membro por ano (PMPY) de R$25.352 (± R$37.762). Pacientes com controle abaixo do ideal (69%) foram associados a 3,3 vezes mais sangramentos graves (5,3% vs. 1,6%; p <0,01) e custos 40% maiores (R$35.384 vs. R$25.352; p < 0,01).

Conclusões:

Mais de 60% dos pacientes estavam abaixo da meta desejada e os custos associados foram significativamente maiores nesta população.

Impact of gender: Rivaroxaban for patients with atrial fibrillation in the XANTUS real-world prospective study

BACKGROUND

The XANTUS study (NCT01606995) demonstrated low rates of stroke and major bleeding in patients with atrial fibrillation (AF) receiving rivaroxaban in clinical practice for the prevention of thromboembolic events (N = 6784).

HYPOTHESIS

Because previous real-world studies have not reported gender-dependent responses to rivaroxaban treatment, this sub-analysis of the XANTUS study investigated the effect of gender on outcomes.

METHODS

The centrally adjudicated outcomes were compared between genders. Primary outcomes were major bleeding and all-cause death. Secondary outcomes included symptomatic thromboembolic events. Multivariable Cox regression analysis was performed to assess the effect of risk factors on outcomes between genders.

RESULTS

A total of 2765 female and 4016 male patients were included in the analysis. Baseline characteristics were generally similar. No nominally significant interaction between gender and risk factors for the study outcomes was observed. Rates of major bleeding, all-cause death and symptomatic thromboembolic events in patients with non-valvular AF receiving rivaroxaban for stroke prevention were similar in men and women; no significant differences in risk factors for these outcomes were observed between genders.

CONCLUSIONS

Further research is needed to better characterize the relative importance of different risk factors on outcomes in men vs women and to determine whether gender differences exist in patients treated with non-vitamin K antagonist oral anticoagulants.

Sex Differences in Quality of Life in Patients With Atrial Fibrillation: A Systematic Review

Background The goal of this literature review was to assess sex differences in the quality of life (QoL) in patients with atrial fibrillation ( AF ) and, if possible, to determine if these are due to AF . Methods and Results The electronic database PubMed was searched on January 23, 2018, using the search terms "QoL", gender differences, " AF " female, and gender to find potential articles that assessed sex differences in QoL in AF patients. In all, 851 articles were identified, from which 25 original studies were eligible for this systematic review. Female AF patients were found to have poorer QoL and more symptoms than male AF patients. They scored lower, predominantly on the physical component score of the Medical Outcomes Study Short-Form 36 Health Survey. Conclusions The available literature consistently describes poorer QoL in female AF patients but does not clearly address whether this is a reflection of sex differences seen in the general population or is related to AF per se. It is also questionable whether the relatively poorer QoL in women is large enough to be of clinical importance.

Long-term blood pressure trajectories and incident atrial fibrillation in women and men: the Tromsø Study

AIMS

To explore sex-specific associations between long-term individual blood pressure (BP) patterns and risk of incident atrial fibrillation (AF) in the general population.

METHODS AND RESULTS

Blood pressure was measured in 8376 women and 7670 men who attended at least two of the three population-based Tromsø Study surveys conducted in 1986-87, 1994-95, and 2001. Participants were followed for incident AF throughout 2013. Latent mixed modelling was used to identify long-term trajectories of systolic BP and hypertension. Cox regression was used to estimate associations between the identified trajectories and incident AF. Elevated systolic BP throughout the exposure period (1986-2001) independently and differentially increased risk of AF in women and men. In women, having elevated systolic BP trajectories doubled AF risk compared to having persistently low levels, irrespective of whether systolic BP increased, decreased, or was persistently high over time, with hazard ratios of 1.88 (95% confidence interval 1.37-2.58), 2.32 (1.61-3.35), and 1.94 (1.28-2.94), respectively. In men, those with elevated systolic BP that continued to increase over time had a 50% increased AF risk: 1.51 (1.09-2.10). When compared to those persistently normotensive, women developing hypertension during the exposure period, and women and men with hypertension throughout the exposure period had 1.40 (1.06-1.86), 2.75 (1.99-3.80), and 1.36 (1.10-1.68) times increased risk of AF, respectively.

CONCLUSION

Long-term BP and hypertension trajectories were associated with increased incidence of AF in both women and men, but the associations were stronger in women.

Sex-specific efficacy and safety of cryoballoon versus radiofrequency ablation for atrial fibrillation: An individual patient data meta-analysis

BACKGROUND

Atrial fibrillation (AF) is a growing health burden, and pulmonary vein isolation (PVI) using cryoballoon (CB) or radiofrequency (RF) represents an attractive therapeutic option. Sex-specific differences in the epidemiology, pathophysiology, and clinical presentation of AF and PVI are recognized.

OBJECTIVE

We aimed at comparing the efficacy, safety, and procedural characteristics of CB and RF in women and men undergoing a first PVI procedure.

METHODS

We searched for randomized controlled trials and prospective observational studies comparing CB and RF ablation with at least 1 year of follow-up. After merging individual patient data from 18 data sets, we investigated the sex-specific (procedure failure defined as recurrence of atrial arrhythmia, reablation, and reinitiation of antiarrhythmic medication), safety (periprocedural complications), and procedural characteristics of CB vs RF using Kaplan-Meier and multilevel models.

RESULTS

From the 18 studies, 4840 men and 1979 women were analyzed. An analysis stratified by sex correcting for several covariates showed a better efficacy of CB in men (hazard ratio for recurrence 0.88; 95% confidence interval 0.78-0.98, P = .02) but not in women (hazard ratio 0.98; 95% confidence interval 0.83-1.16; P = .82). For women and men, the energy source had no influence on the occurrence of at least 1 complication. For both sexes, the procedure time was significantly shorter with CB (-22.5 minutes for women and -27.1 minutes for men).

CONCLUSION

CB is associated with less long-term failures in men. A better understanding of AF-causal sex-specific mechanisms and refinements in CB technologies could lead to higher success rates in women.

Sex-related differences in contemporary biomarkers for heart failure: a review

The use of circulating biomarkers for heart failure (HF) is engrained in contemporary cardiovascular practice and provides objective information about various pathophysiological pathways associated with HF syndrome. However, biomarker profiles differ considerably among women and men. For instance, in the general population, markers of cardiac stretch (natriuretic peptides) and fibrosis (galectin‐3) are higher in women, whereas markers of cardiac injury (cardiac troponins) and inflammation (sST2) are higher in men. Such differences may reflect sex‐specific pathogenic processes associated with HF risk, but may also arise as a result of differences in sex hormone profiles and fat distribution. From a clinical perspective, sex‐related differences in biomarker levels may affect the objectivity of biomarkers in HF management because what is considered to be ‘normal’ in one sex may not be so in the other. The objectives of this review are, therefore: (i) to examine the sex‐specific dynamics of clinically relevant HF biomarkers in the general population, as well as in HF patients; (ii) to discuss the overlap between sex‐related and obesity‐related effects, and (iii) to identify knowledge gaps to stimulate research on sex‐related differences in HF.

Atrial fibrillation among Russian men and women aged 55 years and older: prevalence, mortality, and associations with biomarkers in a population-based study

Objective

To examine the prevalence of atrial fibrillation (AF), its impacts on cardiovascular disease (CVD) and all-cause mortality, and the associations between AF and inflammatory and serum biomarkers in a population-based sample of Muscovites.

Methods

The study is a secondary analysis of data from the Stress, Aging and Health in Russia (SAHR) survey that includes information on 1800 individuals with an average age of 68.5 years at baseline, and on their subsequent mortality during 7.4 years on average. AF is detected by 12-lead electrocardiogram (ECG) and 24-hour Holter monitoring. The statistical analysis includes proportional hazard and logistic regression models.

Results

Of the 1732 participants with relevant Holter data, AF was detected in 100 (74 by ECG and Holter, 26 by Holter only). The prevalence of AF was 5.8% for men and 7.4% for women. The fully adjusted model showed strongly elevated hazard of CVD and all-cause mortality in men and women with long non-self-limiting AF (LAF). LAF was found to be negatively associated with elevated total and low-density lipoprotein cholesterol and to be positively associated with elevated markers of inflammation in women.

Conclusions

The study assessed for the first time the prevalence and the risks of death related to AF among older Russians. LAF was shown to be a strong and independent predictor of CVD and all-cause mortality. AF is unlikely to contribute to the large excess male mortality in Russia. The finding that one-quarter of AF cases were detected only by Holter monitoring demonstrates the usefulness of diagnostics with prolonged ECG registration.

Sex-related differences in prevalence, treatment and outcomes in patients with atrial fibrillation

To analyze sex-related differences about AF prevalence, use of OAC and outcomes focusing on the older age classes. We used administrative data of the Lombardy Region, describing period prevalence, use of OAC and outcomes from 2002 to 2014 for all patients diagnosed with AF. AF prevalence over the 2002-2014 period was higher in males than in females (2.7% vs. 2.1%, p < 0.001), increasing with age. From 2003 to 2014, not treated AF patients decreased mostly in males (from 40.3 to 33.7% with respect to 43.7-39.8% in females). Age-stratified adjusted logistic regression analysis found that females were more likely treated with OAC when < 65 years in 2003 (OR 1.51, 95% CI 1.35-1.69) and in 2014 (OR 1.32, 95% CI 1.13-1.53); contrariwise, were less likely treated with OAC when age ≥ 75 years, in 2003 (OR 0.92, 95% CI 0.86-0.98) and in 2014 (OR 0.77, 95% CI 0.72-0.81).Adjusted Cox regression analysis confirmed that female AF patients had a higher risk of stroke (HR 1.18, 95% CI 1.14-1.21) and a lower risk of major bleeding (HR 0.83, 95% CI 0.80-0.86), while, had a lower risk for all-cause death (HR 0.82, 95% CI 0.80-0.83). AF prevalence was higher in male than in female patients, while thromboembolic risk was higher in female. Older female patients were under-treated with OAC particularly in recent years. Over long-term follow-up, female had a higher risk of stroke and a lower risk of major bleeding and all-cause death.

Personality traits, ventricular tachyarrhythmias, and mortality in patients with an implantable cardioverter defibrillator: 6 years follow-up of the WEBCARE cohort

OBJECTIVE

Risk stratification within the ICD population warrants the examining of the role of protective- and risk factors. Current study examines the association between Type D personality, pessimism, and optimism and risk of ventricular tachyarrhythmias (VTa's) and mortality in patients with a first-time ICD 6 years post implantation.

METHODS

A total of 221 first-implant ICD patients completed questionnaires on optimism and pessimism (Life Orientation Test) and Type D personality (Type D scale DS14) 10 to 14 days after implantation. VTa's and all-cause mortality 6 years post implant comprised the study endpoints.

RESULTS

Ninety (40.7%) patients had experienced VTa's and 37 (16.7%) patients died, 12 (5.4%) due to a cardiac cause. Adjusted logistic regression analysis showed that pessimism was significantly associated with increased risk of VTa's (OR = 1.09; 95% CI = 1.00-1.19; p = .05). Type D personality (OR = 1.05; 95% CI = 0.47-2.32; p = .91) and optimism (OR = 1.00; 95% CI = 0.90-1.12; p = .98) were not associated with VTa's. None of the personality types were associated with mortality.

CONCLUSION

Pessimism was associated with VTa's but not with mortality. No significant association with either of the endpoints was observed for Type D personality and optimism. Future research should focus on the coexistent psychosocial factors that possibly lead to adverse cardiac prognosis in this patient population.

Sex Differences in Advanced Heart Failure Therapies

This in-depth review of sex differences in advanced heart failure therapy summarizes the existing literature on implantable cardioverter defibrillators, biventricular pacemakers, mechanical circulatory support, and transplantation with a focus on utilization, efficacy/clinical effectiveness, adverse events, and controversies. One will learn about the controversies regarding efficacy/clinical effectiveness of implantable cardioverter defibrillators and understand why these devices should be implanted in women even if there are sex differences in appropriate shocks. Individuals will learn about the sex differences with biventricular pacemakers with respect to ventricular remodeling and reduction in heart failure hospitalizations/mortality, as well as, possible mechanisms. We will demonstrate sex differences in heart transplantation and waitlist survival. Despite similar survival for women and men with left ventricular assist devices, there are sex differences in adverse events. These devices do successfully bridge women and men to transplant, yet women are less likely than men to have a left ventricular assist at time of listing and time of transplantation. Finally, one will learn about the concerns regarding poor outcome for men who receive female donor hearts and discover this may not be due to sex, but rather size. More research is needed to better understand sex differences and further improve advanced heart failure therapy for both women and men.

Does an imbalance in circulating vascular endothelial growth factors (VEGFs) cause atrial fibrillation in patients with valvular heart disease?

Background

The pathogenesis of atrial fibrillation (AF) remains unclear. Vascular endothelial growth factors (VEGFs) can stimulate fibrosis within the atrium and ventricle. We hypothesized that there is a relationship between the serum VEGFs/soluble vascular endothelial growth factor receptor (sVEGFRs) levels and AF in patients with valvular heart disease (VHD). This provides a new paradigm for studying AF.

Methods

The plasma levels of VEGF-A, VEGF-C, sVEGFR-1 and sVEGFR-2 were detected by enzyme-linked immunosorbent assay (ELISA). A total of 100 people, consisting of AF patients (long-standing, persistent AF; n=49), sinus rhythm (SR) patients (n=31) and healthy controls (n=20), were included in this study.

Results

The plasma levels of VEGF-A were significantly higher in AF patients compared to healthy control (P<0.05). The plasma levels of sVEGFR-1 were significantly higher in AF compared to SR (P<0.05). The plasma levels of sVEGFR-2 were significantly lower in AF patients compared to SR patients and healthy controls (both P<0.05). There was a significant and negative correlation between AF and the sVEGFR-2 levels in the groups (r=-0.432, P=0.000).

Conclusions

An imbalance in VEGFs and sVEGFRs may contribute to AF by breaking the balance of angiogenesis and lymphangiogenesis. Additionally, sVEGFR-2 may be an important biomarker of AF.

Sex differences in cardiometabolic disorders

The prevalence of cardiometabolic disorders in both women and men has increased worldwide and is linked to a rise in obesity and obesity-associated associated clustering of other cardiometabolic risk factors such as hypertension, impaired glucose regulation and dyslipidemia. However, the predominance of common types of cardiometabolic disorders such as heart failure, atrial fibrillation and ischemic heart disease is sex specific, and our identification of these and the underlying mechanisms is only just emerging. New evidence suggests that sex hormones, sex-specific molecular mechanisms and gender influence glucose and lipid metabolisms, as well as cardiac energy metabolism, and function. Here we review sex differences in cardiometabolic risk factors, associated preclinical and clinical cardiac disorders and potential therapeutic avenues.

Sex Differences in Presentation, Quality of Life, and Treatment in Chinese Atrial Fibrillation Patients: Insights from the China Atrial Fibrillation Registry Study

<strong>BACKGROUND</strong> There is a growing recognition of sex-related disparities in atrial fibrillation (AF). However, limited data is available in Chinese AF patients. <strong>MATERIAL AND METHODS</strong> We compared symptoms, quality of life (QoL), and treatment of AF according to sex from the China AF Registry study. <strong>RESULTS</strong> We studied 14 723 patients with non-valvular AF, of whom 5645 patients (38.3%) were female. Women were older than men (67.5±10.6 vs. 62.2±12.2). Compared to men, women had more comorbidities and a higher proportion of CHA₂DS₂-VASC score ≥2. Women with AF experienced more severe or disabling symptoms than men (33.7% vs. 22.9% in age <75 group; 40.3% vs. 28.7% in age ≥75 group; both P<0.0001). After multivariate analysis, women with AF still had lower QoL (OR 0.69; 95%CI, 0.63-0.76; P<0.0001). Women tended to have lower rates of ablation and rhythm-control drug use in those aged <75 years. Oral anticoagulant use was low and had no sex difference in AF patients with a CHA₂DS₂-VASC score ≥2. <strong>CONCLUSIONS</strong> In Chinese AF patients, women were older and more symptomatic, and had worse QoL. Despite all these differences, women tended to receive less rhythm-control treatment in those aged <75 years. Oral anticoagulant was substantially underused in high stroke risk patients, regardless of sex.

Sex Differences in Electrophysiology, Ventricular Tachyarrhythmia, Cardiac Arrest and Sudden Cardiac Death Following Acute Myocardial Infarction

BACKGROUND

Women experience less appropriate implantable cardioverter-defibrillator (ICD) interventions and are underrepresented in randomised ICD trials. Sex-differences in inducible and spontaneous ventricular tachycardia/fibrillation (VT/VF), cardiac arrest and sudden cardiac death (SCD) early post-myocardial infarction (MI) require further study.

METHODS

Consecutive ST-elevation MI patients with left ventricular ejection fraction (LVEF)≤40% underwent electrophysiology study (EPS) to target early prevention of SCD. An ICD was implanted for a positive (inducible monomorphic VT) but not a negative (no arrhythmia or inducible VF) EPS. The combined primary endpoint of VT/VF (spontaneous or ICD-treated), cardiac arrest or SCD was assessed using competing risk survival analysis in women versus men with adjustment for confounders. Logistic regression was used to determine independent predictors of inducible VT at EPS.

RESULTS

A total of 403 patients (16.9% female) underwent EPS. Women were significantly older than men but with similar LVEF (31.5 ± 6.3 versus 31.6 ± 6.4%, p = 0.91). Electrophysiology study was positive for inducible VT in 22.1% and 33.4% (p = 0.066) and an ICD implanted in 25.0% and 33.4% (p = 0.356) of women versus men. Appropriate ICD activations (VT/VF) occurred in 5.9% of women and 36.6% of men (p = 0.012). The adjusted cumulative primary endpoint incidence was significantly lower in women than men (1.6% versus 26.5%, p = 0.03). Female sex was not an independent predictor of inducible VT at EPS (HR 0.63, 95% CI 0.33-1.23, p = 0.178).

CONCLUSIONS

Women with early post-MI cardiomyopathy had lower VT/VF, cardiac arrest and SCD, compared to men. In ICD recipients the rate of appropriate activations was six-fold less in women compared to men.