Effect of Female Sex on Cardiac Arrhythmias

Abstract

We performed a systematic literature review to examine the effect of female sex on cardiac electrophysiology and arrhythmias. Women have faster resting heart rates yet longer QTc intervals. Women also have shorter PR and QRS intervals; these are presumed to be due to the small heart size of women and hormonal effects on ion channels. Women are two times more likely to experience atrioventricular nodal re-entry tachycardia than men. In contrast to atrioventricular nodal re-entry tachycardia, accessory-pathway-mediated atrial arrhythmias are less common in women, and women have more concealed and fewer manifest accessory pathways. Supraventricular tachycardia in women varies with the menstrual cycle and is more frequent in the luteal phase and inversely correlated with estrogen levels. Atrial fibrillation (AF) is less prevalent in women, but the absolute number of women with AF is higher because AF prevalence increases with age and women live longer. Also, complications of AF are greater in women. Women are generally less prone to ventricular arrhythmias, but they comprise a higher percentage of symptomatic subjects with congenital long QT syndrome and are more often affected by drugs that prolong the QT. Women are less prone to arrhythmias during pregnancy although they commonly complain of palpitations, which are sometimes related to the increase in heart rate during pregnancy. Clinicians should explore the relationship of arrhythmias to the menstrual cycle in female patients and should know that the menstrual cycle may affect the induction of arrhythmias during electrophysiological testing. Clinicians should also be aware that the arrhythmia and the result of clinical trials examining arrhythmia treatment may have different implications in women than in men.

Cardiac Potassium Channel Subtypes: New Roles in Repolarization and Arrhythmia

“…It has been recognized that additional factors contribute to the manifestation of the arrhythmia and the observable symptoms. The impact of factors such as gender, age, seasonal changes, circadian rhythm, and triggers such as auditory stimuli or exercise, or physiological challenges such as hypokalemia have been reported (42,89,152,165,227,290,414,486). Beyond environmental modifiers, the presence of additional genetic modifiers is well-recognized.…”

Women and heart disease, the underrecognized burden: sex differences, biases, and unmet clinical and research challenges

“…For example, circulating androgens seem to shorten the QT interval and protect against torsades de pointes [4]. After puberty, women with both congenital and acquired long QT syndrome (LQTS) are at higher risk of cardiac events compared with men [3,5].…”

“…There is some evidence that the QT interval shortens during the luteal phase, which occurs after ovulation when oestrogen levels are lowest and progesterone levels highest. These basic electrophysiological differences have direct clinical correlations [3]. For example, circulating androgens seem to shorten the QT interval and protect against torsades de pointes [4].…”

“…In studies of electrophysiology testing for supraventricular tachycardia (SVT), AVNRT is easier to induce in premenopausal women during the premenstrual phase or at the onset of menses [3].…”

Characteristics of Cardiac Rhythm and Conduction Abnormalities Diagnosed in Mobile Emergency Units in Central Romania

“…It is well known that there are important differences between males and females in the clinical characteristics of many cardiovascular diseases, which are also extended for rhythm and conduction disturbances, due to various hormonal and constitutional differences. [32][33][34] The effects of sex hormones on the conductibility and excitability of the heart vary between genders, as testosterone leads to a shortening of the QT interval, while estrogen leads to an elongation of the QT interval. 35 A study on 5,116 patients found that the resting heart rate of female patients is higher with up to 3-5 beats per minute.…”