Adrienne S Zion

University at Buffalo, The State University of New York, Buffalo, NY, United States

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Publications (23)55.13 Total impact

  • Joseph L Izzo, Adrienne S Zion
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    ABSTRACT: While it may seem at first that antihypertensive drug combinations run counter to the desire to 'personalize' the management of hypertension, the best combinations have predictable efficacy in different individuals and subpopulations. Race is probably not a valid surrogate for clinically meaningful genetic variation or guide to therapy. Most guidelines suggest similar blood pressure goals for different races but drug treatment recommendations have diverged. In the United States, race is not considered to be a major factor in drug choice, but in England and other countries, initial therapy with renin-angiotensin system blocking drugs is not recommended in Blacks. In this review we: (1) examine new trends in race-based research; (2) emphasize the weaknesses of race-based treatment recommendations; and (3) explore the effects of a new combination, renin inhibition (aliskiren) and amlodipine, in African Americans.
    Therapeutic Advances in Cardiovascular Disease 06/2011; 5(3):169-78. DOI:10.1177/1753944711409615 · 2.13 Impact Factor
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    Joseph L Izzo, Adrienne S Zion
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    ABSTRACT: There are more clinical trials investigating angiotensin receptor blockers (ARBs) in diabetes than any other drug class, ranging from early "prevention" trials to the treatment of individuals with advanced organ damage. In its earliest manifestations, visceral adiposity predisposes to hypertension and hyperglycemia (metabolic syndrome). In these individuals, ARB therapy delays the progression to chronic hypertension and may also delay the progression to overt diabetes. Based on the increased cardiovascular disease risk of the metabolic syndrome, which is similar to stage 1 hypertension, both lifestyle modification and ARB therapy are justifiable. ARB therapy has also been found to delay the onset of microalbuminuria and retinopathy. In established diabetic nephropathy, ARB therapy is recommended as a standard alternative to angiotensin-converting enzyme inhibition to reduce macroalbuminuria and delay the progression to end-stage disease. Finally, large trials in ischemic heart disease, heart failure, and stroke have demonstrated clear benefits of ARB therapy. Because ARBs have side effect rates equal to placebo and far lower than any other antihypertensive drug class, the benefit/risk ratio is highly favorable across the entire spectrum of diabetic disease. Thus, ARB therapy is a highly attractive alternative for individuals at any stage of diabetes and with any pattern of complications.
    Journal of Clinical Hypertension 04/2011; 13(4):290-5. DOI:10.1111/j.1751-7176.2011.00447.x · 2.96 Impact Factor
  • Adrienne S Zion, Joseph L Izzo
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    ABSTRACT: Optimal antihypertensive therapy requires a multimodal approach based on lifestyle modification and, for most individuals, combination drug therapy. Recommendations from experts suggest that a combination of an agent that blocks the renin-angiotensin system (RAS), together with a vasodilator (generally a calcium-channel blocker or a thiazide-type diuretic), is most likely to control blood pressure and provide the widest overall cardiovascular protection. Understanding the opportunities afforded by the combination of RAS blockade with a calcium-channel blocker requires a discussion of basic and clinical science data. One new concept is that of 'global' or total RAS blockade. The impact of the RAS can be diminished or blocked by several different classes of drugs (central sympatholytics, ╬▓-blockers, renin inhibitors, ACE inhibitors or ARBs); what is most important is how effectively the overall impact of angiotensin II is blunted. A second new concept is that the complementary actions of RAS blockers and calcium-channel blockers are best explained on the basis of diminished intracellular calcium availability in excitable tissue (sympathetic neurons and vascular smooth muscle cells) via parallel actions that reduce angiotensin II type-1 receptor stimulation and L-channel-mediated calcium flux. Aliskiren is the first of the direct renin inhibitors, the newest subclass of RAS blockers. In both short- and long-term studies, aliskiren has been shown to be similar in efficacy and tolerability compared with other RAS blockers, with the added benefit that its effects persist longer. Outcome studies with aliskiren are currently underway.
    Expert Review of Cardiovascular Therapy 03/2011; 9(4):421-7. DOI:10.1586/erc.11.23
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    ABSTRACT: Recent studies have failed to show an improvement in cardiovascular mortality with intensive glycemic control and aggressive glycated hemoglobin (A(1c)) targets less than 7.0%. Excessive hypoglycemic episodes with intensive glucose-lowering therapy are thought to be a major factor in the failure to show cardiovascular benefit in these trials. In this article, we review the physiology of glucose metabolism, the cardiovascular pathophysiology of hypoglycemia, and the trials with an intensive glucose-lowering strategy that have studied microvascular and macrovascular complications. We also review the current non-insulin drugs available for the treatment of diabetes and their potential hypoglycemic and cardiovascular impacts.
    Current Atherosclerosis Reports 03/2010; 12(2):88-95. DOI:10.1007/s11883-010-0093-8 · 3.06 Impact Factor
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    ABSTRACT: The effect of thiazolidinediones (TZDs) on the progression of atherosclerosis in diabetes patients remains unclear. There has been heightened interest in recent years in this class of diabetes medications due to the non-glycemic lowering effects, such as altering lipids, inflammation and hematologic profiles. There have been several exciting studies over the past few years focused on the mechanism of action of the TZDs with respect to alteration in the cardio-metabolic profile in diabetes patients. New tools such as intravascular ultrasound have been used to follow plaques characteristics over time on a much more sensitive scale than has ever been possible in the past by coronary angiograms. These advances have enabled researchers to follow closely the macrovascular effects of different anti-atherosclerotic medications such as statins and TZDs. This article reviews the pathophysiology of atherosclerosis in diabetes, the role that TZDs play in this process and the imaging trials looking at the progression or regression of atherosclerosis in patients treated with TZDs.
    Vascular Health and Risk Management 02/2010; 6:1-8.
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    ABSTRACT: Restoration of the sympathovagal (S/V) balance, involving a lowering of sympathetic and/or an augmentation of vagal modulation or a combination of both is associated with improvements in cardiovascular morbidity and mortality. To determine whether acupuncture exerts a favorable influence upon resting blood pressure and sympathovagal balance, a single-blind cross-over investigation was used to study the acute effects of acupuncture on S/V balance in normal healthy subjects. The ANOVA revealed a significant lowering of the sympathovagal balance (LF:HF) during rest for the acupuncture treatment from pre (4 +/- 2 nu) to post (2.2 +/- 1.8 nu)(p < 0.05). No such change was seen during sham treatment. The ANOVA revealed significant differences in systolic blood pressures during rest (114 +/- 4 vs. 108 +/- 3 mmHg) for the acupuncture treatment (p < 0.05). No significance was found during the sham treatment. The ANOVA failed to reveal any significant improvements in sympathovagal balance during the sustained isometric contraction. The clinical significance of these findings appears to suggest that acupuncture treatment might be beneficial in lowering blood pressure at rest. Furthermore, the lowering of the blood pressure might be in part due to a lowering of the sympathovagal balance. These findings are of importance since acupuncture treatments are non-pharmacological and have no known detrimental side-effects. This investigation employed healthy volunteers, yet acupuncture has been found to have more potent effects in animal models of hypertension and or in the presence of an autonomic imbalance.
    The American Journal of Chinese Medicine 01/2010; 38(5):839-47. DOI:10.1142/S0192415X10008287 · 2.63 Impact Factor
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    ABSTRACT: Impaired fasting glucose (IFG) contributes to microvascular and macrovascular complications and increased cardiovascular disease risk. Although type 2 diabetes is largely considered to occur as a result of IFG, understanding of physiologic and associated management targets is uniformly lacking among health care professionals. Once definitions are standardized, diagnostic criteria and screening tools may help to identify individuals at risk sooner, thereby minimizing the rapid deterioration that often results. To counter the rising pandemic of obesity and diabetes, it is important to understand the vascular risk of IFG and impaired glucose tolerance in patients at risk.
    Current Cardiology Reports 11/2009; 11(6):460-467. DOI:10.1007/s11886-009-0066-0
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    ABSTRACT: Impaired fasting glucose (IFG) contributes to microvascular and macrovascular complications and increased cardiovascular disease risk. Although type 2 diabetes is largely considered to occur as a result of IFG, understanding of physiologic and associated management targets is uniformly lacking among health care professionals. Once definitions are standardized, diagnostic criteria and screening tools may help to identify individuals at risk sooner, thereby minimizing the rapid deterioration that often results. To counter the rising pandemic of obesity and diabetes, it is important to understand the vascular risk of IFG and impaired glucose tolerance in patients at risk.
    Current Cardiology Reports 11/2009; 11(6):460-7.
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    ABSTRACT: Aerobic exercise is a powerful mechanism by which cardiovascular and autonomic parameters may be improved. We sought to quantify the extent of benefit that could be achieved by a short-term monitored exercise regimen on several autonomic parameters during recognized mental and physical stressors in young normotensive African-American men matched for a family history of hypertension, a group at high risk for the development of hypertension. Autonomic modulations were derived using spectral decomposition of the electrocardiogram and beat-to-beat blood pressures (BPs). Arterial compliance was obtained using contour analysis of the radial artery pulse wave. The analysis of variance revealed that compared with a matched sedentary control group, aerobic capacity of the trained group significantly increased by 16%. Autonomic modulations, arterial compliance and BP responses significantly improved during some of the stressors, whereas no such improvements were seen in the control group. Attenuated responses, mediated through a favourable shift in sympathovagal balance and enhanced arterial compliance, provide mechanistic evidence of how certain variables may be improved due to aerobic conditioning in a population at high risk for the development of hypertension.
    Journal of human hypertension 11/2008; 23(4):267-73. DOI:10.1038/jhh.2008.125 · 2.69 Impact Factor
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    ABSTRACT: The prevalence of type 2 diabetes mellitus (T2DM) is growing at an alarming rate and reaching epidemic proportions, and cardiovascular disease continues to be one of the leading causes of death in the United States. The key relationship between these two diseases (knowing that T2DM is a strong risk factor for cardiovascular disease) is insulin resistance and the detrimental effect it has on macrovasculature. Thiazolidinediones (TZDs) are peroxisome proliferator-activated receptor gammaagonists that are beneficial in the treatment of T2DM and have the added benefit of modifying lipid profiles. This review discusses the basic science linking insulin resistance to atherosclerosis and describes the major TZD trials in the recent literature. It also addresses the clinical implications of these studies and media scrutiny surrounding the recent controversial report that TZDs may be linked to an increased risk of myocardial infarction.
    Current Atherosclerosis Reports 05/2008; 10(2):134-41. · 3.06 Impact Factor
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    ABSTRACT: The prevalence of type 2 diabetes mellitus (T2DM) is growing at an alarming rate and reaching epidemic proportions, and cardiovascular disease continues to be one of the leading causes of death in the United States. The key relationship between these two diseases (knowing that T2DM is a strong risk factor for cardiovascular disease) is insulin resistance and the detrimental effect it has on macrovasculature. Thiazolidinediones (TZDs) are peroxisome proliferator-activated receptor? agonists that are beneficial in the treatment of T2DM and have the added benefit of modifying lipid profiles. This review discusses the basic science linking insulin resistance to atherosclerosis and describes the major TZD trials in the recent literature. It also addresses the clinical implications of these studies and media scrutiny surrounding the recent controversial report that TZDs may be linked to an increased risk of myocardial infarction.
    Current Atherosclerosis Reports 03/2008; 10(2):134-141. DOI:10.1007/s11883-008-0020-4 · 3.06 Impact Factor
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    ABSTRACT: Human immunodeficiency virus (HIV) is associated with cardiovascular (CV) and autonomic dysfunction, however the effects of fitness on vascular and autonomic mechanisms in HIV disease are unknown. We studied forty-eight subjects (40.4 +/- 4.2 years) in a cross-sectional design matched for age, gender, BMI, and fitness. Participants were assigned to 1 in 4 groups: 1) Healthy Unfit (HU), 2) Healthy Fit (HF), 3) HIV Positive Unfit (HPU), and 4) HIV Positive Fit (HPF). Fitness was assessed via open-circuit spirometry; arterial compliance and autonomic modulations were measured via applanation tonometry and power spectral analysis, respectively, and baroreflex sensitivity was obtained using the alpha index. Arterial compliance was augmented in HPF vs. HPU [7.4 +/- 1.9 mmHg x second vs. 4.4 +/- 1.7 mmHg x second (P = 0.006)]. Parasympathetic modulation was higher in HPF vs. HPU [2244.5 +/- 2997.6 msecond(2) vs. 489.1 +/- 552.9 msecond(2) (P < 0.05)]. Sympathetic modulation was lower in HPF vs. HU [4.7 +/- 5.0 mmHg(2) vs. 12.9 +/- 9.7 mmHg(2) (P < 0.05)]. Baroreflex sensitivity was higher in HPF vs. HPU [17.3 +/- 10.2 msecond/mmHg vs. 7.4 +/- 3.8 msecond/mmHg (P = 0.003)], and HPF vs. HU [17.3 +/- 10.2 msecond/mmHg vs. 6.2 +/- 3.0 msecond/mmHg (P = 0.004)]. Augmentations in arterial compliance and baroreflex sensitivity associated with fitness portent an improved CV and autonomic profile for HIV-positive individuals. Physical activity may be an adjuvant method to enhance the overall vascular health in HIV-compromised individuals.
    Clinical Autonomic Research 12/2007; 17(6):341-8. DOI:10.1007/s10286-007-0441-0 · 1.86 Impact Factor
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    ABSTRACT: Hypertension remains a common public health challenge because of its prevalence and increase in co-morbid cardiovascular diseases. Black males have disproportionate pathophysiological consequences of hypertension compared with any other group in the United States. Alterations in arterial wall compliance and autonomic function often precede the onset of disease. Accordingly, our purpose was to investigate whether differences exist in arterial compliance and autonomic function between young, healthy African-American males without evidence of hypertension and age- and gender-matched non-African-American males. All procedures were carried out noninvasively following rest. Arterial compliance was calculated as the integrated area starting at the well-defined nadir of the incisura of the dicrotic notch to the end of diastole of the radial artery pulse wave. Power spectral analysis of heart rate and blood pressure variability provided distributions representative of parasympathetic and sympathetic modulations and sympathovagal balance. Baroreflex sensitivity (BRS) was calculated using the sequence method. Thirty-two African-American and twenty-nine non-African-American males were comparable in anthropometrics and negative family history of hypertension. t-Tests revealed lower arterial compliance (5.8 +/- 2.4 vs. 8.6 +/- 4.0 mmHg. s; P = 0.0017), parasympathetic modulation (8.9 +/- 1.1 vs. 9.7 +/- 1.1 ln ms2; P = 0.0063), and BRS (13.7 +/- 7.3 vs. 21.1 +/- 8.5 ms/mmHg; P = 0.0007) and higher sympathovagal balance (2.9 +/- 3.2 vs. 1.5 +/- 1.1; P = 0.03) in the African-American group. In summary, differences exist in arterial compliance and autonomic balance in African-American males. These alterations may be antecedent markers of disease and valuable in the detection of degenerative cardiovascular processes in individuals at risk.
    AJP Heart and Circulatory Physiology 09/2003; 285(2):H457-62. DOI:10.1152/ajpheart.00497.2002 · 4.01 Impact Factor
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    ABSTRACT: Published normative data of noninvasive blood pressures (BPs) and autonomic modulations have been primarily derived from the finger arteriole using the Finapres (Ohmeda Co., Englewood, CO), a device that is no longer manufactured. Currently, beat-to-beat BP are obtained from the radial artery using the Colin tonometer. We compared BP and autonomic parameters in a crossover design between the two devices in 29 subjects during seated rest and a 0.1-Hz breathing protocol. In addition, we tested whether finger arteriolar BP differences were due to pressure changes exerted by the radial tonometer. Uniformly, BP measured at the radial artery were significantly higher than those from the finger arteriole. Radial BP (106 +/- 19.5 mm Hg) were higher than finger arteriolar BP (95.8 +/- 13.7 mm Hg) (P <.005). Tonometric baroreflex sensitivity (BRS) (24.0 +/- 18 msec/mm Hg) was higher compared to photoplethysmographic BRS (12.0 +/- 7.7 msec/mm Hg; P <.0003). Systolic BP (radial artery) (115 +/- 25 mm Hg) were higher compared to finger arteriolar BP (97.7 +/- 19 mm Hg; P <.0025) during breathing, as was BRS (25.9 +/- 11.6 msec/mm Hg v 21.5 +/- 11.6 msec/mm Hg; P <.05). Differences in the low frequency systolic BP (LF(SBP)), representative of sympathetic vasomotor modulation, between the two methods, whether absolute, normalized, or log-transformed were not observed. There were no differences in arteriolar BP values in the presence or absence of radial artery tonometric pressure. These findings indicate that differences exist in systolic BP and BRS using the tonometer (radial artery) versus the Finapres (Ohmeda Co.) (finger arteriole). Furthermore, these differences are not due to pressure exerted by the radial artery tonometer that supplies blood to the finger arteriole.
    American Journal of Hypertension 05/2003; 16(5 Pt 1):371-4. DOI:10.1016/S0895-7061(03)00039-6 · 3.40 Impact Factor
  • Medicine &amp Science in Sports &amp Exercise 01/2002; 34(5). DOI:10.1097/00005768-200205001-01514 · 4.46 Impact Factor
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    ABSTRACT: Loss of autonomic balance characterized by increased sympathetic activity and decreased vagal activity has been implicated as a major cardiovascular risk factor. Aspirin's cardioprotective abilities involve a multitude of physiologic processes. However, the effects of aspirin on cardiac autonomic activity are unknown. In a double-blind crossover study, 22 subjects randomly received either aspirin or placebo in the amounts of 325 mg with each meal (three times per day) over a 2.5-day period. The total amount of aspirin ingested was 2,275 mg, which resulted in plasma levels of 3.3 mg/dl. At the conclusion of each treatment, subjects were evaluated for autonomic physiology activity using standard autonomic tests. Power spectral analyses of the electrocardiograms were used to delineate autonomic function. A 2 x 4 repeated measures analysis of variance revealed significant and favorable changes in autonomic activity after the use of aspirin. Specifically, at rest high-frequency (HF) power was significantly higher (mean, 1,090 + 1,463.5 msec2) compared with the placebo (mean, 692 742 msec2) (p <0.05). Low-frequency (LF) power was significantly reduced (mean, 963 745 msec2) after aspirin compared with placebo (mean, 1,100 906 msec2). After the aspirin treatment, a significantly lower LF-to-HF power ratio (mean, 1.7 2 msec2) was noted at rest when compared with the placebo (mean, 2.5 2.7 msec2) (p <0.05). Similar significant trends were seen during the sustained isometric contraction after aspirin therapy for HF power (mean 210 2.15 msec2) compared with placebo (mean, 213 184 msec2) (p <0.05). Accordingly, the LF-to-HF power ratio was lower as well when compared to placebo treatment (mean, 2.3 3.5 msec2) (mean, 5.3 8.4 msec2) (p <0.05). No differences were found in breathing rates for hemodynamic variables between any of the protocols. The significant reduction of LF-to-HF ratio, a marker of sympathovagal balance, for both protocols appeared to be largely due to a withdrawal of LF modulation and concomitant but lesser increase in HF modulation. Favorable alterations in autonomic outflow through prostaglandin inhibition may be one of the mechanisms by which low therapeutic amounts of aspirin provide prophylactic cardioprotection.
    Clinical Autonomic Research 09/2000; 10(4):197-201. DOI:10.1007/BF02291356 · 1.86 Impact Factor
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    ABSTRACT: Mechanoreceptor contribution to efferent autonomic outflow is incompletely understood. To determine the effects of mechanoreceptor stimulation on autonomic reflexes, we compared autonomic responses in 34 subjects using a cross-over, counter-balanced design, in which hemodynamic, electromyographic, metabolic, and autonomic data were gathered during rest, passive, and active movement protocols. Because metaboreceptors and ventilatory responses influence autonomic outflow we verified and controlled for these influences during all protocols through comparisons of breath-by-breath gas exchange measurements. Verification of active and passive movements was made via electromyographic recordings of the moving legs. Spectral analysis of R-R variability was used to assess autonomic activity, and low to high frequency ratios were considered representative of sympathovagal balance. A repeated measures analysis of variance revealed significant modulating effects of mechanoreceptor stimulation on sympathovagal balance during passive movement upon efferent autonomic outflow (p < 0.01) independent of central command, chemoreceptor, and metaboreceptor stimulation. Furthermore, breathing frequency and volume were identical for both movement protocols. Therefore, findings in this investigation suggest that modulating influences are being exerted by mechanoreceptor stimulation on autonomic outflow to the heart.
    Clinical Autonomic Research 09/1998; 8(4):201-5. DOI:10.1007/BF02267782 · 1.86 Impact Factor
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    ABSTRACT: The pathogenesis of blood pressure (BP) rise in aging women remains unexplained, and one of the many incriminating factors may include abnormalities in arteriolar resistance vessels. The aim of this study was to determine the effects of unopposed estrogen on arteriolar distensibility, baroreceptor sensitivity (BRS), BP changes, and rate-pressure product (RPP). We tested the hypotheses that estrogen replacement therapy (ERT) enhances arteriolar distensibility and ameliorates BRS, which leads to decreases in BP and RPP. Postmenopausal women participated in a single-blind crossover study; the participants of this study, after baseline measurements, were randomly assigned to receive estrogen (ERT) or a drug-free treatment with a 6-wk washout period between treatments. The single-blind design was instituted because subjects become unblinded due to physiological changes (i.e., fluid shifts, weight gain, and secretory changes) associated with estrogen intake. However, investigators and technicians involved in data collection and analyses remained blind. After each treatment, subjects performed identical autonomic tests, during which electrocardiograms, beat-by-beat BPs, and respiration were recorded. The area under the dicrotic notch of the BP wave was used as an index of arteriolar distensibility. The magnitude of the reflex bradycardia after a precipitous rise in BP was used to determine BRS. Power spectral analysis of heart rate variability was used to assess autonomic activity. BPs were recorded from resistance vessels in the finger using a beat-by-beat photoplethysmographic device. RPP, a noninvasive marker of myocardial oxygen consumption, was calculated. Repeated-measures analyses of variance revealed a significantly enhanced arteriolar distensibility and BRS after ERT (P < 0.05). A trend of a lower sympathovagal balance at rest was observed after ERT, however, this trend did not reach statistical significance (P = 0.061) compared with the other treatments. The above autonomic changes produced significantly lower systolic and diastolic BP changes and RPPs (P < 0.05) at rest and during isometric exercise. We conclude that short-term unopposed ERT favorably enhances arteriolar distensibility, BRS, and hemodynamic parameters in postmenopausal women. These findings have clinical implications in the goals for treating cardiovascular risk factors in aging women.
    The American journal of physiology 06/1998; 274(5 Pt 2):H1539-44. · 3.28 Impact Factor
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    ABSTRACT: Weight reduction, either by dietary or surgical means, is associated with prolongation of the heart rate corrected QT interval (QTc = QT/R-R0.5) and, on occasion, sudden death. Screening subjects with obesity before weight loss for prolonged QTc intervals is an accepted practice, although at present, there are no guidelines for whether subjects should be fasting before electrocardiogram (EKG) evaluation. The aim of this study was to test the hypothesis that EKG QTc interval duration is independent of meal ingestion. The hypothesis was tested in 11 healthy subjects who ingested a 500-kcal formula meal. A small decrease in absolute QT interval and a steady decline in R-R interval were observed for up to 60 minutes after formula ingestion. The QTc interval increased above baseline at 15 minutes (p < 0.007) after meal, a change that persisted for the 1-hour postmeal observation period. Spectral analysis of EKG R-R intervals (low-/high-frequency amplitude ratio) indicated a change in cardiac autonomic flow after meal ingestion. The QTc interval did not lengthen and R-R low-/high-frequency amplitude ratio remained unchanged in eight subjects evaluated in a similar manner but in whom isovolumic amounts of water replaced the meal. These observations suggest that (1) cardiac repolarization changes with fasting and feeding, (2) the QTc interval is influenced by meal intake, and (3) the autonomic nervous system may play a role in meal-related QTc changes. These findings have implications for the evaluation of patients with obesity before starting and during weight loss treatment.
    Obesity research 11/1997; 5(6):531-7. DOI:10.1002/j.1550-8528.1997.tb00573.x · 4.95 Impact Factor
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    ABSTRACT: Variability in blood pressure (BPV) is influenced by vascular sympathetic drive as well as autonomic control of the heart. Evidence suggests that elimination of cardiac autonomic control, as measured by heart period variability (HPV), produces a reduction in BPV at rest but an increase in BPV during challenge. We recently showed that the BPV response to psychological challenge, which principally produces cardiac parasympathetic withdrawal, was inversely related to the subject's level of cardiac control. In the current study we examined the BPV response to orthostatic tilt, a sympathetic stressor. Subjects were 22 healthy men and women who differed in cardiac control due in part to differences in aerobic capacity. HPV and BPV were measured noninvasively on a beat-to-beat basis. Tilt produced significant increases in heart rate and diastolic blood pressure and a significant decrease in high frequency HPV. As predicted, changes in BPV in response to tilt were inversely related to resting HPV. Results are interpreted in terms of a model of cardiovascular control which holds that BPV originates from feedforward effects of central control of the heart, feedback effects mediated through the baroreflexes, and direct sympathetic vascular effects.
    The American journal of physiology 10/1997; 273(3 Pt 2):H1427-31. · 3.28 Impact Factor

Publication Stats

228 Citations
55.13 Total Impact Points

Institutions

  • 2011
    • University at Buffalo, The State University of New York
      • Department of Medicine
      Buffalo, NY, United States
  • 1995–2011
    • Columbia University
      • • Teachers College
      • • Division of Behavioral Science
      • • Department of Rehabilitation and Regenerative Medicine
      • • College of Physicians and Surgeons
      New York, New York, United States
  • 2008–2009
    • University of Texas Health Science Center at San Antonio
      • • Division of Hospital Medicine
      • • Division of Cardiology
      San Antonio, TX, United States