Obesity As a Risk Factor for Sustained Ventricular Tachyarrhythmias in MADIT II Patients

Pietrasik, Grzegorz; Goldenberg, Ilan; McNitt, Scott; Moss, Arthur J.; Zaręba, Wojciech

doi:10.1111/j.1540-8167.2006.00680.x

Cited by 94 publications

(69 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…After control measurements, obesity hypertension was produced by feeding a high-fat diet for 28 days before reducing fat intake to maintain body weight for the remainder of the study. The experimental protocol consisted of 1) control, days 1-3; 2) days 4 -31, high fat (development of obesity and hypertension); 3) days 32-63, reduced fat (established obesity hypertension); 4) days [35][36][37][38][39][40][41], baroreflex activation (1 wk); 5) days [42][43][44][45][46][47][48], recovery (1 wk); 6) day 49, surgical bilateral renal denervation by procedures previously used in our laboratory (33); and 7) day 63, end of study (2 wk after renal denervation).…”

Section: Methodsmentioning

confidence: 99%

“…obesity; hypertension; heart rate variability; baroreflex; sympathetic nervous system THE CAUSAL LINK between obesity and hypertension is well recognized. Clinical and experimental evidence also indicate that obesity has a profound impact on cardiac automaticity (44), which may increase the risk for atrial and ventricular arrhythmias, leading causes of morbidity and mortality in the industrialized world (4,7,17,42,59,60). The mechanisms that mediate the proarrhythmogenic effects of obesity have received little attention.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Chronic baroreflex activation restores spontaneous baroreflex control and variability of heart rate in obesity-induced hypertension

Iliescu

Tudorancea

Irwin

et al. 2013

American Journal of Physiology-Heart and Circulatory Physiology

View full text Add to dashboard Cite

Iliescu R, Tudorancea I, Irwin ED, Lohmeier TE. Chronic baroreflex activation restores spontaneous baroreflex control and variability of heart rate in obesity-induced hypertension. Am J Physiol Heart Circ Physiol 305: H1080 -H1088, 2013. First published August 2, 2013; doi:10.1152/ajpheart.00464.2013.-The sensitivity of baroreflex control of heart rate is depressed in subjects with obesity hypertension, which increases the risk for cardiac arrhythmias. The mechanisms are not fully known, and there are no therapies to improve this dysfunction. To determine the cardiovascular dynamic effects of progressive increases in body weight leading to obesity and hypertension in dogs fed a high-fat diet, 24-h continuous recordings of spontaneous fluctuations in blood pressure and heart rate were analyzed in the time and frequency domains. Furthermore, we investigated whether autonomic mechanisms stimulated by chronic baroreflex activation and renal denervation-current therapies in patients with resistant hypertension, who are commonly obese-restore cardiovascular dynamic control. Increases in body weight to ϳ150% of control led to a gradual increase in mean arterial pressure to 17 Ϯ 3 mmHg above control (100 Ϯ 2 mmHg) after 4 wk on the high-fat diet. In contrast to the gradual increase in arterial pressure, tachycardia, attenuated chronotropic baroreflex responses, and reduced heart rate variability were manifest within 1-4 days on high-fat intake, reaching 130 Ϯ 4 beats per minute (bpm) (control ϭ 86 Ϯ 3 bpm) and ϳ45% and Ͻ20%, respectively, of control levels. Subsequently, both baroreflex activation and renal denervation abolished the hypertension. However, only baroreflex activation effectively attenuated the tachycardia and restored cardiac baroreflex sensitivity and heart rate variability. These findings suggest that baroreflex activation therapy may reduce the risk factors for cardiac arrhythmias as well as lower arterial pressure. obesity; hypertension; heart rate variability; baroreflex; sympathetic nervous system THE CAUSAL LINK between obesity and hypertension is well recognized. Clinical and experimental evidence also indicate that obesity has a profound impact on cardiac automaticity (44), which may increase the risk for atrial and ventricular arrhythmias, leading causes of morbidity and mortality in the industrialized world (4,7,17,42,59,60). The mechanisms that mediate the proarrhythmogenic effects of obesity have received little attention. Low heart rate variability has been identified not only as a predictor of but also as a risk factor for developing life-threatening cardiac arrhythmias (7,8,26,46,50,56,57) and, together with impaired baroreflex control of heart rate, is a common finding in obese individuals (6,18,20,51,58). Alterations in cardiac autonomic neural regulation are the substrate for reductions in both heart rate variability and baroreflex sensitivity and, consequently, may increase risk for cardiac arrhythmias (7,8). While sustained activation of the sympathetic nervous system has been shown t...

show abstract

Section: Methodsmentioning

confidence: 99%

mentioning

confidence: 99%

Chronic baroreflex activation restores spontaneous baroreflex control and variability of heart rate in obesity-induced hypertension

Iliescu

Tudorancea

Irwin

et al. 2013

American Journal of Physiology-Heart and Circulatory Physiology

View full text Add to dashboard Cite

show abstract

“…20 Sudden death could be related to arrhythmic events, including lethal ventricular fibrillation, because patients with MetS had significantly higher values of corrected QT interval and QT dispersion on ECG, which reflects myocardial refractoriness and electrical instability. 21 In the Multicenter Automatic Defibrillator Implantation Trial II (MADIT-II) study, 22 obesity (BMI ≥30 kg/m 2 ) was a risk factor for sustained ventricular tachyarrhythmia in patients after myocardial infarction with severe LV dysfunction (LV ejection fraction <30%).…”

Section: Sudden Death and Arrhythmiamentioning

confidence: 99%

Cardiac Adiposity and Global Cardiometabolic Risk New Concept and Clinical Implication

Shimabukuro

2009

Circ J

View full text Add to dashboard Cite

he obesity epidemic is a global public health concern that threatens to reduce life expectancy around the world. 1,2 Excess weight, particularly abdominal obesity, causes or exacerbates cardiovascular and metabolic risk factors, including hypertension, dyslipidemia, and type 2 diabetes mellitus (T2DM). [3][4][5] These risk factors synergistically increase the likelihood of morbidity and mortality of cardiovascular disease (CVD), 6,7 which leads to rising healthcare costs. 8 Actions promoting health check-ups for obesity-related conditions and prevention strategies have been proposed; 9 however, the theoretical background has not been fully coordinated, and, most importantly, the actions to reduce abdominal adiposity has not been fully validated in terms of global cardiovascular risk management. The contribution of abdominal obesity to global cardiometabolic risk will be reviewed and the potential, underlying mechanisms and management strategy will be also discussed. Contribution of Abdominal Obesity to CVDRecent studies show that waist circumference is directly related to all-cause mortality when adjusted for body mass index (BMI), 6 and is also strongly associated with the mortality and morbidity of CVD. 7 The facts highlight the importance of visceral fat over subcutaneous fat deposits and promote the incorporation of waist circumference into the diagnosis of metabolic syndrome (MetS). 3-5 Each entity of CVD will be discussed below. Coronary Heart Disease (CHD)In the landmark INTERHEART study, 10 Yusuf et al reported the effect of various measures of adiposity on rates of acute myocardial infarction (AMI) by comparing 12,461 AMI cases and 14,637 standardized controls of varying ethnicity from 52 countries. BMI showed a modest association with AMI (unadjusted odds ratio (OR) 1.44 for 1 st vs 5 th quintile), but this association was lost after adjustment for other risk factors. Meanwhile, the adjusted OR for quintile of the waist-to-hip ratio was successively greater than that of the previous one (OR 1.15, 1.39, 1.90, and 2.52, respectively). Waist-to-hip ratio, and the waist and hip circumferences were highly associated with the risk of AMI, even after adjustment for other risk factors (OR for 1 st vs 5 th quintiles, 1.75, 1.33, and 0.76, respectively; P<0.0001). More recently, investigators in the EPIC-Norfolk study reported that waist circumference, but not BMI, was a significant estimate for all CHD events during 9.1 years and that hip circumference appeared to protect against CHD. 11 Taken together, a redefinition of obesity based on waist circumference, instead of BMI, is a better estimate of CHD in most ethnic groups, and the notion can be supported that abdominal adiposity, not subcutaneous adiposity, is closely linked to the onset of CHD. The presence of MetS appears to be associated with worse outcomes in patients with AMI 12 or in patients following coronary artery bypass surgery. 13 In subjects with angiographically normal coronary arteries, acetylcholine-induced coronary vasoconstriction correlated ...

show abstract

“…16 In an attempt to identify those criteria, post hoc analyses of the second Multicenter Automatic Defibrillator Implantation Trial (MADIT II) revealed several clinical criteria associated with an increased risk for ventricular arrhythmias resulting in appropriate device therapy. [17][18][19] Thus far, however, in patients with low LVEF, no criteria have been recognized that may identify patients at low risk of ventricular arrhythmias during follow-up. If possible to identify a low-risk population, ICD therapy in this group may be reconsidered.…”

mentioning

confidence: 99%

Predicting Ventricular Arrhythmias in Patients With Ischemic Heart Disease

Borleffs

Scherptong

Man

et al. 2009

Circ: Arrhythmia and Electrophysiology

139

122

View full text Add to dashboard Cite

Background-In patients with primary prevention implantable cardioverter-defibrillators (ICDs), the incidence of life-threatening ventricular arrhythmias resulting in ICD therapy is relatively low, prompting for better risk stratification. The aim of this study was to assess the value of the QRS-T angle for prediction of ICD therapy and mortality in primary prevention patients with ischemic heart disease. Methods and Results-ICD patients (nϭ412, 361 men; age, 63Ϯ11 years) with ischemic heart disease and a left ventricular ejection fraction Յ40% were included. After device implantation, the occurrence of appropriate ICD therapy and mortality was noted. A survival analysis was performed comparing patients with a planar QRS-T angle Յ90°( nϭ124, 30%) with patients with a planar QRS-T angle Ͼ90°before device implantation. Furthermore, patients with a spatial QRS-T angle Յ100°(nϭ56, 14%) were compared with patients with a spatial QRS-T angle Ͼ100°, before implantation. For patients with a planar QRS-T angle Ͼ90°as compared with Յ90°, the adjusted hazard ratio for the occurrence of appropriate device therapy was 2.4 (95% CI, 1.1 to 5.2); a spatial QRS-T angle Ͼ100°was associated with an adjusted hazard ratio of 7.3 (95% CI, 1.0 to 53.8). Furthermore, a spatial QRS-T angle Յ100°exhibited a positive predictive value of 98% (95% CI, 95 to 100) for the prediction of an appropriate therapy-free follow-up. Conclusions-A wide QRS-T angle is a strong predictor of appropriate device therapy in primary prevention ICD recipients with ischemic heart disease. Furthermore, a spatial QRS-T angle Յ100°might be of value in the identification of patients in whom, although currently indicated, ICD treatment should be reconsidered. (Circ Arrhythmia Electrophysiol. 2009;2:548-554.)

show abstract

Obesity As a Risk Factor for Sustained Ventricular Tachyarrhythmias in MADIT II Patients

Abstract: Our findings suggest that in nondiabetic patients with ischemic left ventricular dysfunction, a BMI > or =30 kg/m(2) is an independent risk factor for ventricular tachyarrhythmias.

Cited by 94 publications

References 21 publications

Chronic baroreflex activation restores spontaneous baroreflex control and variability of heart rate in obesity-induced hypertension

Chronic baroreflex activation restores spontaneous baroreflex control and variability of heart rate in obesity-induced hypertension

Cardiac Adiposity and Global Cardiometabolic Risk New Concept and Clinical Implication

Predicting Ventricular Arrhythmias in Patients With Ischemic Heart Disease

Contact Info

Product

Resources

About