Atrioventricular nodal re-entrant tachycardias (AVNRT) occur significantly more often in women than in men, presumably related to hormonal effects on AV conduction [27]. The prevalence of AVNRT in women peaks in the second and third decennium and around menopause. Cyclic hormonal variations in premenopausal women influence the occurrence of AVNRT with a predominance in the luteal phase when progesterone levels are at highest [28, 29]. During pregnancy and after delivery, an increased incidence of supraventricular tachycardia (SVT) and especially AVNRT has been described [30]. For atrioventricular re-entrant tachycardia, using a bypass tract outside the AV node, no difference in incidence between men and woman has been described.

Paroxysmal supraventricular tachycardia’s (PSVT) are later diagnosed in women than in men and are often associated with feelings of anxiety, panic and undetermined vibrations in the chest [31]. Symptoms can easily be misinterpreted as being from psychological origin [32]. This may also lead to later referral and eventually even for delay in radiofrequency (RF) ablation in women, such as shown in patient case A.

Men are at 1.5-fold higher risk than women to develop atrial fibrillation (AF) during lifetime [33]. However, given their longer life-expectancy, the absolute number of women with AF is higher [34]. With the increase in obesity, sedentary lifestyle and hypertension over the past decades, the absolute number of individuals with AF is rising. In the Swedish adult population the prevalence is currently estimated at 2.9%, not counting individuals with ‘silent AF’, which is comparable with the 3% prevalence as mentioned in the recent 2016 ESC guidelines AF [35, 36]. Atrial fibrillation is independently associated with a twofold increased risk of all-cause mortality in women and a 1.5-fold increase in men [33, 37, 38]. In the Euro Heart Survey on AF it was found that women with AF were generally older, with a lower quality of life, more co-morbidity and more cardiac symptoms compared to men [39, 40]. Women also had more often heart failure (HF) with preserved left ventricular systolic function (HFpEF), and less frequent HF with reduced ejection fraction systolic (HFrEF). In the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF) women with AF had more symptoms and a worse quality of life than men [41].

It has been disputed whether AF is more strongly associated with the risk of stroke and CVD mortality in women than in men [38, 42–45]. In a recent meta-analysis of more than 30 studies in >4.3 million patients, AF was associated with a higher risk of all cause (RR 1,12, 95% CI 1.07–1.17) and an almost twofold CVD mortality in women than in men [46]. Women are also prone to more severe strokes when they do occur [47]. A worse LA function in women than in men with AF contributes to their higher stroke risk [48]. This is closely related to sex-differences in cardiac and arterial remodeling with ageing, with more impaired diastolic dysfunction and arterial stiffening in women compared to men [49, 50]. Nevertheless, women are less likely to receive anticoagulation and undergo fewer cardioversions, AF ablations or pulmonary vein isolations than men [41, 51–54]. Also, women have more peri-procedural complications of AF catheter ablations and a higher recurrence-rate of AF after cardioversion [55, 56].

The CHA2DS2-VASc risk score has included female sex as a risk factor for stroke prevention (Table 10.1). Recommended is to use vitamin K antagonists or novel oral anticoagulants (NOACs) when the risk score is ≥1 for men, and ≥2 for women, balancing the expected stroke reduction, bleeding risk, and patient preference [36]. Of note is that women are underrepresented in the majority of NOAC-trials and that risk of abnormal uterine bleeding in premenopausal women is largely unknown [57, 58].

In patients with ischemic heart disease (IHD) the risk of sudden cardiac death is more than twofold higher in men than in women [59]. This may importantly be related to the higher obstructive atherosclerosis burden and sex-differences in plaque compositions in men compared to women [60]. The risk for ventricular tachycardias in non-obstructive coronary artery disease (NOCAD) and coronary microvascular disease (CMD), which are important manifestations of IHD in women, is less well studied. It is assumed that the likelihood of ventricular tachycardias is higher during periods of ischemia. Autonomic changes, such as an increase in sympathetic tone, which frequently occurs in women after menopause, enhances the risk for VT/VF [61, 62]. Chronic psychological stress and depression, more often present in women after menopause than in similarly aged men, may further induce autonomic changes. This leads to a higher use of antidepressants, which is also associated with an increased risk for sudden cardiac death (SCD) [63].

In non-ischemic cardiomyopathies (NICM), there is no evidence for any sex difference in arrhythmias or chance for SCD. Recent studies debate whether an implantable cardioverter-defibrillator (ICD) backup is useful in NICM patients [64, 65]. The Brugada syndrome affects men almost 9× more often and more severely than women. Men with Brugada syndrome have more frequently syncope and SCD than women [66, 67]. It is assumed that testosterone-levels in the ion channels play an important role in the observed sex difference [68].

In congenital long QT-syndrome (LQTS), there is an unexplained female prevalence of disease. Women are especially at a higher risk of cardiac events in the period after giving birth, whereas men are more likely to suffer syncope and SCD until puberty [27, 69]. Acquired LQTS is clinically more common than congenital LQTS and is usually seen with electrolyte abnormalities or the use of medications that prolong ventricular repolarization. Nevertheless, about 30% of acquired LQTS appear to be concealed form of congenital LQTS [70]. Women exhibit longer QTc intervals and are more prone to develop Torsades de pointes during administration of some antiarrhythmic drugs [71]. Up to 70% of the cases of medication-induced Torsades de pointes are in women [72]. Especially Vaughn Williams class IA and class III antiarrhythmic drugs (e.g. quinidine and sotalol) enhance the risk for Torsades de pointes. Most important drugs that prolong QT-interval are antihistamines, certain antibiotics and psychopharmaca such a amytriptiline and lithium (www.​qtdrugs.​org). Class IC antiarrythmic drugs (e.g. flecainide) may also increase the QT interval and therefore increase the risk for Torsades de pointes [73]

Women represent a minority (10–13%) in VT ablation-studies, but are at higher risk for VT recurrence after 1 year. In a recent study in 2062 patients with ischemic and non-ischemic recurrent VT’s undergoing ablation, of which 266 (12.9%) were women, it was found that women were younger, with higher ejection fractions and less VT storms than men [74]. In women, the 1-year success rate was lower with significantly higher rates of VT recurrence. More data are needed to distinguish between sex differences in referral patterns, arrhythmia substrate, and treatment bias.

Women more often have sinus node dysfunction and lower rates of AV conduction abnormalities [75]. In the age group above 80, men receive more dual chamber pacing compared to women. Women more peri-procedural complications, such as pneumothorax and hematomas. These complications do not negatively affect survival rates. [76].

It has been debated whether women profit equally from implantable defibrillator devices (ICD) than men [77–79]. In a large meta-analysis in primary prevention studies, no sex difference in mortality was found [80]. Women have fewer ICD-shocks than men and a lower susceptibility to arrhythmia-triggers, which may justify their lower primary ICD implantation rates. Although the benefit for ICD therapy in secondary prevention is similar among men and women, despite they are offered less often ICD therapy [81, 82]. In (additional) cardiac resynchronization therapy (CRT) a recent FDA meta-analysis of three major clinical trials with mild heart failure (HF) confirmed that the indication for CRT in women seems to be at a shorter QRS duration than in men [83, 84]. This has not resulted yet in a sex-specific treatment advise in the latest 2016 ESC guidelines HF [85].

Most aging women undergo screening mammograms at regular intervals. The presence of an implanted medical device in the breast may affect the quality of the mammograms [86]. We recently investigated barriers in females and radiographers for mammography and found that increased pain in women and anxiety in both parties were important determinants of lower compression force and suboptimal positioning technique [87]. About 20% of women with devices had serious doubts on attending screening. Despite the very low chance to damage the leads and pacemaker/ICD devices itself, it may be recommended in women with anxiety to undergo mammography at a radiology department in a hospital with possibilities for PM/ICD control afterwards.