Gender Differences in Autonomic Modulation of Ventricular Repolarization in Humans

Nakagawa, Mikiko; Ooie, Tatsuhiko; Ou, Baiqing; Ichinose, Masashi; Takahashi, Naohiko; Hara, Masahide; Yonemochi, Hidetoshi; Saikawa, Tetsunori

doi:10.1046/j.1540-8167.2005.40455.x

Cited by 79 publications

(40 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…4,5 Similar to these previous reports in AB individuals, QTc interval is larger in women with SCI than in men with and without SCI. Based on the present findings of similar QTc interval prolongation in women with and without SCI, greater propensity for arrhythmogenesis in women with SCI may be similar to that seen in AB women, but this needs further investigation.…”

Section: Discussionsupporting

confidence: 88%

“…4,5 This has been associated with greater susceptibility to the development of Torsades de Pointes in women. 6 However, recent findings suggest that factors other than autonomic tone, such as hormonal modulation, may be responsible for gender differences in QTc interval.…”

Section: Introductionmentioning

confidence: 99%

“…6 However, recent findings suggest that factors other than autonomic tone, such as hormonal modulation, may be responsible for gender differences in QTc interval. 4 Thus, despite the potential autonomic disruption associated with SCI, gender differences in QTc interval may prevail.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Gender differences in QTc interval in young, trained individuals with lower spinal cord injury

et al. 2007

View full text Add to dashboard Cite

Study design: Cross-sectional comparison. Objective: To examine gender differences in rate-corrected QT interval (QTc), an index of ventricular depolarization/repolarization, in young, trained men and women with lower spinal cord injury (SCI) and able-bodied (AB) controls. Setting: University of Illinois at Urbana-Champaign, Exercise and Cardiovascular Research Lab, USA. Methods: Subjects consisted of 16 athletes with SCI (eight men and eight women) and 16 agematched AB active controls (eight men and eight women). QT interval dynamics was derived from ECG recordings and rate corrected using the Bazett formula. Results: Men with SCI had QTc similar to that of AB men (369.377.5 versus 357.973.0 ms, P40.05). Women with SCI had QTc similar to that of AB women (400.074.6 versus 385.276.5 ms, P40.05). AB women had longer QTc interval than AB men, and SCI women had longer QTc than SCI men (Po0.05). Conclusions: Gender differences in ventricular depolarization/repolarization are present in trained individuals with SCI. Thus, similar to their AB gender-matched peers, women with SCI have longer QTc intervals and may be at greater risk for the development of untoward cardiac arrhythmias than men with SCI.

show abstract

Section: Discussionsupporting

confidence: 88%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Gender differences in QTc interval in young, trained individuals with lower spinal cord injury

et al. 2007

View full text Add to dashboard Cite

show abstract

“…At present there is no transfer function allowing the prediction of the QT sequence from the cardiac cycle sequence. This situation is further complicated by the dependence of the duration of ventricular repolarization on sympathetic influences (11). While it is possible to assess global NE release from the heart (as we also did in the present study), the actual dynamics of NE release from cardiac sympathetic terminals is unknown.…”

Section: Discussionmentioning

confidence: 87%

QT interval variability and cardiac norepinephrine spillover in patients with depression and panic disorder

Baumert¹,

Lambert²,

Dawood³

et al. 2008

American Journal of Physiology-Heart and Circulatory Physiology

View full text Add to dashboard Cite

Nalivaiko E. QT interval variability and cardiac norepinephrine spillover in patients with depression and panic disorder. Am J Physiol Heart Circ Physiol 295: H962-H968, 2008. First published July 3, 2008 doi:10.1152/ajpheart.00301.2008.-Suggestions were made that increased myocardial sympathetic activity is reflected by elevated QT variability (dynamic changes in QT interval duration). However, the relationship between QT variability and the amount of norepinephrine released from the cardiac sympathetic terminals is unknown. We thus attempted to assess this relationship. The study was performed in 17 subjects (12 with major depressive disorder and 5 with panic disorder). Cardiac norepinephrine spillover (measured by direct catheter technique coupled with norepinephrine isotope dilution methodology) was assessed before and 4 mo after treatment with selective serotonin reuptake inhibitor (SSRI) antidepressants. The distribution of the cardiac norepinephrine spillover was bimodal, with the majority of patients having values of Յ10 ng/min. There was a positive correlation between cardiac norepinephrine spillover and corrected QT interval (r ϭ 0.7, P ϭ 0.03) but not with any of the QT variability measures. However, in a subgroup of five patients who had high levels of cardiac norepinephrine spillover (Ͼ20 ng/min) a tendency for a strong positive correlation with variance of QT intervals (r ϭ 0.9, P ϭ 0.08) was observed. There were significant correlations between the severity of depression and QT variability indexes normalized to the heart rate [QTVi and QT interval/R-R interval (QT/RR) coherence] and between the severity of anxiety and the QT/RR residual and regression coefficient, respectively. Treatment with SSRI antidepressants substantially reduced depression score but did not affect any of the QT variability indexes. We conclude that in depression/panic disorder patients with near-normal cardiac norepinephrine levels QT variability is not correlated with cardiac norepinephrine spillover and is not affected by treatment with SSRI. sympathetic activity; antidepressants AN EXCESSIVE CARDIAC SYMPATHETIC activity is a recognized risk factor for cardiac morbidity and mortality. In a range of clinical contexts, elevated cardiac sympathetic outflow has been demonstrated to contribute to ventricular arrhythmias (10), sudden death (6), myocardial stunning (21), and left ventricular hypertrophy (19). Direct assessment of norepinephrine (NE) spillover (the "gold standard" for assessing cardiac sympathetic activity) is a complex, invasive procedure, and cardiac sympathetic activity is still most frequently assessed by measuring mean heart rate or assessing its dynamic variability (1). Obviously, heart rate reflects autonomic influences only at the level of the cardiac pacemaker region. Because different regions of the heart could be under independent autonomic control (7, 12, 13), it becomes increasingly evident that indexes reflecting sympathetic influences in the ventricular myocardium might be of better predictive and ...

show abstract

“…6,7 Right ventricular outflow tract (RVOT) VAs occur more frequently in women than men, although men consistently predominate with LV ostial VAs. 6,7,11,13 Premature ventricular contractions have been more common than ventricular tachycardias. 6,7,11…”

Section: Clinical Presentation Of Vas Originatingmentioning

confidence: 99%

The Left Ventricular Ostium

Yamada

Litovsky

Kay

2008

Circ: Arrhythmia and Electrophysiology

143

View full text Add to dashboard Cite

I diopathic ventricular arrhythmias (VAs) arising from the left ventricle (LV) are often accessible for catheter ablation from the aortic sinuses of Valsalva or adjacent to the mitral annulus (MA). 1 The aortic and mitral valves are direct apposition and attach to an elliptical opening at the base of the LV known as the LV ostium. 2 The VAs arising from this region are being increasingly recognized as targets for catheter ablation. [3][4][5][6][7] This review describes the anatomic features of the LV ostium and the electrocardiographic, electrophysiological, and angiographic characteristics that are relevant to the mapping and ablation of these arrhythmias. Anatomy of the LV OstiumThe dominant central structure of the heart is the junction of the aorta with the LV. Fundamental for understanding idiopathic VAs arising near the aortic and mitral valves are 2 concepts: first, these arrhythmias arise from the LV ostium ( Figure 1); and second, the LV ostium is covered by the aorto-ventricular membrane, a tough fibrous structure which is perforated by the aorta anteriorly and the mitral valve (MV) posteriorly ( Figure 2). The anatomic concept of the LV ostium and its covering, the aorto-ventricular membrane, are based on the pioneering work of McAlpine. 2 The Anterior Division of the Aorto-Ventricular Membrane Within the LV OstiumThe aorta is joined to the LV ostium at an angle of Ϸ30% above the horizontal plane with the noncoronary cusp (NCC) most inferiorly and the left coronary cusp (LCC) most superiorly (Figures 1 and 3A). Rather than a circular fibrous aortic annulus, in reality the anatomy is much more complex with 3 membranous attachments at the base of the right, left, and noncoronary cusps (Figure 2). These attachments consist of less than one half of the circumference of each aortic sinus cusp (ASC). The most anterior attachment of the aorta to the LV ostium is the right coronary cusp (RCC) (Figure 3B), which is in contact with the LV ostial myocardium over a distance of 16.5Ϯ3 mm ( Figure 4A). 2 When viewed from the superior aspect of the RCC, LV muscle can be seen at the base of the cusp. The RCC has an average depth of 23.2Ϯ2.7 mm with the ostium of the right coronary artery (RCA) located Ϸ15 mm from the nadir of the cusp ( Figure 3C). 2 The LCC forms the lateral and postero-lateral attachment of the aorta to the LV ostium (Figure 2). The LCC is in contact with the LV ostium in the antero-lateral portion of the cusp for 7.4Ϯ3 mm, significantly less than for the RCC. 2 The posterior portion of the LCC is not in direct contact with LV myocardium but apposes the left fibrous trigone (LFT), a tough membranous region joining the aorta to the anterior leaflet of the MV ( Figure 5A). Thus, a catheter positioned in the antero-lateral portion of the LCC will usually record a larger ventricular electrogram than atrial electrogram whereas a catheter positioned in the more posterior portion of this cusp will often record a larger atrial electrogram. The left main coronary artery ostium is located 15 to 20 mm above ...

show abstract

Gender Differences in Autonomic Modulation of Ventricular Repolarization in Humans

Abstract: While sympathetic stimulation and autonomic blockade modulated the dynamics of ventricular repolarization in both sexes, it was more pronounced in women. This gender difference may partially account for the susceptibility of women to arrhythmogenesis.

Cited by 79 publications

References 31 publications

Gender differences in QTc interval in young, trained individuals with lower spinal cord injury

Gender differences in QTc interval in young, trained individuals with lower spinal cord injury

QT interval variability and cardiac norepinephrine spillover in patients with depression and panic disorder

The Left Ventricular Ostium

Contact Info

Product

Resources

About