NONINVASIVE MEASUREMENTS OF NORMAL VALUES OF STROKE VOLUME AND TOTAL PERIPHERAL RESISTANCE IN AN ELDERLY POPULATION ACCOUNTING FOR AGE AND SEX DIFFERENCES

The hemodynamic and metabolic effects of long-term (5 day) infusion of human atrial natriuretic factor (ANF) were examined in conscious chronically instrumented sheep. Infusion of ANF at 20 micrograms/h, a rate below the threshold for an acute natriuretic effect, decreased blood pressure by 9 +/- 1 mmHg on day 5, associated with a fall in calculated total peripheral resistance. On day 1, ANF reduced cardiac output, stroke volume, and blood volume, effects that were associated with an increase in heart rate and calculated total peripheral resistance and a small decrease in blood pressure. On days 4 and 5 there was a small increase in urine volume and sodium excretion. On day 5 an increase in water intake and body weight was observed. No change was seen in plasma concentrations of renin, arginine vasopressin, glucose, adrenocorticotropic hormone, or protein. This study suggests that the short-term hypotensive effect of ANF results from a reduction in cardiac output associated with a fall in both stroke volume and effective blood volume. However, after 5 days of infusion, ANF lowers blood pressure via a reduction in total peripheral resistance.

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Differential contribution of central command to the cardiovascular responses during static exercise of ankle dorsal and plantar flexion in humans

Journal of Applied Physiology ◽

10.1152/japplphysiol.00740.2010 ◽

2011 ◽

Vol 110 (3) ◽

pp. 670-680 ◽

Cited By ~ 11

Author(s):

Nan Liang ◽

Tomoko Nakamoto ◽

Seina Mochizuki ◽

Kanji Matsukawa

Keyword(s):

Stroke Volume ◽

Total Peripheral Resistance ◽

Plantar Flexion ◽

Peripheral Resistance ◽

Cardiovascular Responses ◽

Central Command ◽

Static Exercise ◽

Maximum Increase ◽

Arterial Blood ◽

Differential Contribution

To examine whether central command contributes differently to the cardiovascular responses during voluntary static exercise engaged by different muscle groups, we encouraged healthy subjects to perform voluntary and electrically evoked involuntary static exercise of ankle dorsal and plantar flexion. Each exercise was conducted with 25% of the maximum voluntary force of the right ankle dorsal and plantar flexion, respectively, for 2 min. Heart rate (HR) and mean arterial blood pressure (MAP) were recorded, and stroke volume, cardiac output (CO), and total peripheral resistance were calculated. With voluntary exercise, HR, MAP, and CO significantly increased during dorsal flexion (the maximum increase, HR: 12 ± 2.3 beats/min; MAP: 14 ± 2.0 mmHg; CO: 1 ± 0.2 l/min), whereas only MAP increased during plantar flexion (the maximum increase, 6 ± 2.0 mmHg). Stroke volume and total peripheral resistance were unchanged throughout the two kinds of voluntary static exercise. With involuntary exercise, there were no significant changes in all cardiovascular variables, irrespective of dorsal or plantar flexion. Furthermore, before the force onset of voluntary static exercise, HR and MAP started to increase without muscle contraction, whereas they had no significant changes with involuntary exercise at the moment. The present findings indicate that differential contribution of central command is responsible for the different cardiovascular responses to static exercise, depending on the strength of central control of the contracting muscle.

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Effect of sympathetic blockade on diurnal variation of hemodynamic patterns

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1989.256.3.r778 ◽

1989 ◽

Vol 256 (3) ◽

pp. R778-R785 ◽

Cited By ~ 4

Author(s):

M. I. Talan ◽

B. T. Engel

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Cardiac Output ◽

Stroke Volume ◽

Total Peripheral Resistance ◽

Peripheral Resistance ◽

Base Line ◽

Sympathetic Blockade ◽

Selective Blockade ◽

Arterial Blood

Heart rate, stroke volume, and intra-arterial blood pressure were monitored continuously in each of four monkeys, 18 consecutive h/day for several weeks. The mean heart rate, stroke volume, cardiac output, systolic and diastolic blood pressure, and total peripheral resistance were calculated for each minute and reduced to hourly means. After base-line data were collected for approximately 20 days, observation was continued for equal periods of time under conditions of alpha-sympathetic blockade, beta-sympathetic blockade, and double sympathetic blockade. This was achieved by intra-arterial infusion of prazosin, atenolol, or a combination of both in concentration sufficient for at least 75% reduction of response to injection of agonists. The results confirmed previous findings of a diurnal pattern characterized by a fall in cardiac output and a rise in total peripheral resistance throughout the night. This pattern was not eliminated by selective blockade, of alpha- or beta-sympathetic receptors or by double sympathetic blockade; in fact, it was exacerbated by sympathetic blockade, indicating that the sympathetic nervous system attenuates these events. Because these findings indicate that blood volume redistribution is probably not the mechanism mediating the observed effects, we have hypothesized that a diurnal loss in plasma volume may mediate the fall in cardiac output and that the rise in total peripheral resistance reflects a homeostatic regulation of arterial pressure.

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Abnormal cardiovascular response to nitroglycerin in migraine

Cephalalgia ◽

10.1177/0333102419881657 ◽

2019 ◽

Vol 40 (3) ◽

pp. 266-277

Author(s):

Willebrordus PJ van Oosterhout ◽

Guus G Schoonman ◽

Dirk P Saal ◽

Roland D Thijs ◽

Michel D Ferrari ◽

...

Keyword(s):

Heart Rate ◽

Cardiac Output ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Stroke Volume ◽

Total Peripheral Resistance ◽

Cardiovascular Response ◽

Peripheral Resistance ◽

Cardiovascular Responses ◽

Initial Increase

Introduction Migraine and vasovagal syncope are comorbid conditions that may share part of their pathophysiology through autonomic control of the systemic circulation. Nitroglycerin can trigger both syncope and migraine attacks, suggesting enhanced systemic sensitivity in migraine. We aimed to determine the cardiovascular responses to nitroglycerin in migraine. Methods In 16 women with migraine without aura and 10 age- and gender-matched controls without headache, intravenous nitroglycerin (0.5 µg·kg−1·min−1) was administered. Finger photoplethysmography continuously assessed cardiovascular parameters (mean arterial pressure, heart rate, cardiac output, stroke volume and total peripheral resistance) before, during and after nitroglycerin infusion. Results Nitroglycerin provoked a migraine-like attack in 13/16 (81.2%) migraineurs but not in controls ( p = .0001). No syncope was provoked. Migraineurs who later developed a migraine-like attack showed different responses in all parameters vs. controls (all p < .001): The decreases in cardiac output and stroke volume were more rapid and longer lasting, heart rate increased, mean arterial pressure and total peripheral resistance were higher and decreased steeply after an initial increase. Discussion Migraineurs who developed a migraine-like attack in response to nitroglycerin showed stronger systemic cardiovascular responses compared to non-headache controls. The stronger systemic cardiovascular responses in migraine suggest increased systemic sensitivity to vasodilators, possibly due to insufficient autonomic compensatory mechanisms.

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Autonomic Cardiovascular Dysregulation at Rest and During Stress in Chronically Low Blood Pressure

Journal of Psychophysiology ◽

10.1027/0269-8803/a000204 ◽

2019 ◽

Vol 33 (1) ◽

pp. 39-53 ◽

Cited By ~ 1

Author(s):

Stefan Duschek ◽

Alexandra Hoffmann ◽

Casandra I. Montoro ◽

Gustavo A. Reyes del Paso

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Heart Rate Variability ◽

Cardiac Output ◽

Stroke Volume ◽

Total Peripheral Resistance ◽

Baroreflex Sensitivity ◽

Peripheral Resistance ◽

Control Group ◽

Low Blood Pressure

Abstract. Chronic low blood pressure (hypotension) is accompanied by symptoms such as fatigue, reduced drive, faintness, dizziness, cold limbs, and concentration difficulties. The study explored the involvement of aberrances in autonomic cardiovascular control in the origin of this condition. In 40 hypotensive and 40 normotensive subjects, impedance cardiography, electrocardiography, and continuous blood pressure recordings were performed at rest and during stress induced by mental calculation. Parameters of cardiac sympathetic control (i.e., stroke volume, cardiac output, pre-ejection period, total peripheral resistance), parasympathetic control (i.e., heart rate variability), and baroreflex function (i.e., baroreflex sensitivity) were obtained. The hypotensive group exhibited markedly lower stroke volume, heart rate, and cardiac output, as well as higher pre-ejection period and baroreflex sensitivity than the control group. Hypotension was furthermore associated with a smaller blood pressure response during stress. No group differences arose in total peripheral resistance and heart rate variability. While reduced beta-adrenergic myocardial drive seems to constitute the principal feature of the autonomic impairment that characterizes chronic hypotension, baroreflex-related mechanisms may also contribute to this state. Insufficient organ perfusion due to reduced cardiac output and deficient cardiovascular adjustment to situational requirements may be involved in the manifestation of bodily and mental symptoms.

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Cardiovascular Effects of Moxibustion at Jen Chung (Go-26) during Halothane Anesthesia in Dogs

The American Journal of Chinese Medicine ◽

10.1142/s0192415x75000268 ◽

1975 ◽

Vol 03 (03) ◽

pp. 245-261 ◽

Cited By ~ 9

Author(s):

Do Chil Lee ◽

Myung O. Lee ◽

Donald H. Clifford

Keyword(s):

Heart Rate ◽

Cardiac Output ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Stroke Volume ◽

Total Peripheral Resistance ◽

Venous Pressure ◽

Peripheral Resistance ◽

Cardiovascular Effects ◽

Halothane Anesthesia

The cardiovascular effects of moxibustion at Jen Chung (Go-26) in 10 dogs under halothane anesthesia were compared to 5 dogs under halothane anesthesia without moxibustion and 5 dogs under halothane anesthesia in which moxibustion was effected at a neutral or non-acupuncture site. Cardiac output, stroke volume, heart rate, mean arterial pressure, central venous pressure, total peripheral resistance, pH, PaCO2, PaO2 and base deficit were measured over a two-hour period. A significant increase in cardiac output and stroke volume and a significant decrease in the total peripheral resistance were observed in the group which was stimulated by moxibustion at Jen Chun (Go-26). Heart rate, mean arterial pressure and pulse pressure were significantly increase during the early part of the two-hour period in the same group. The cardiovascular effects of moxibustion at Jen Chung (Go-26) which were observed at the end of the two hours were also present in two dogs in which measurements were continued for two additional hours.

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Estimation of the total peripheral resistance baroreflex impulse response from spontaneous hemodynamic variability

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00852.2007 ◽

2008 ◽

Vol 294 (1) ◽

pp. H293-H301 ◽

Cited By ~ 2

Author(s):

Xiaoxiao Chen ◽

Jong-Kyung Kim ◽

Javier A. Sala-Mercado ◽

Robert L. Hammond ◽

Rafat I. Elahi ◽

...

Keyword(s):

Impulse Response ◽

Mathematical Analysis ◽

Total Peripheral Resistance ◽

Arterial Compliance ◽

Peripheral Resistance ◽

Noninvasive Measurements ◽

Extended Technique ◽

Arterial Blood ◽

Before And After ◽

Cardiovascular Simulator

We previously developed a mathematical analysis technique for estimating the static gain values of the arterial total peripheral resistance (TPR) baroreflex ( GA) and the cardiopulmonary TPR baroreflex ( GC) from small, spontaneous beat-to-beat fluctuations in arterial blood pressure, cardiac output, and stroke volume. Here, we extended the mathematical analysis so as to also estimate the entire arterial TPR baroreflex impulse response [ hA( t)] as well as the lumped arterial compliance (AC). The extended technique may therefore provide a linear dynamic characterization of TPR baroreflex systems during normal physiological conditions from potentially noninvasive measurements. We theoretically evaluated the technique with respect to realistic spontaneous hemodynamic variability generated by a cardiovascular simulator with known system properties. Our results showed that the technique reliably estimated hA( t) [error = 30.2 ± 2.6% for the square root of energy ( EA), 19.7 ± 1.6% for absolute peak amplitude ( PA), 37.3 ± 2.5% for GA, and 33.1 ± 4.9% for the overall time constant] and AC (error = 17.6 ± 4.2%) under various simulator parameter values and reliably tracked changes in GC. We also experimentally evaluated the technique with respect to spontaneous hemodynamic variability measured from seven conscious dogs before and after chronic arterial baroreceptor denervation. Our results showed that the technique correctly predicted the abolishment of hA( t) [ EA = 1.0 ± 0.2 to 0.3 ± 0.1, PA = 0.3 ± 0.1 to 0.1 ± 0.0 s−1, and GA = −2.1 ± 0.6 to 0.3 ± 0.2 ( P < 0.05)] and the enhancement of GC [−0.7 ± 0.44 to −1.8 ± 0.2 ( P < 0.05)] following the chronic intervention. Moreover, the technique yielded estimates whose values were consistent with those reported with more invasive and/or experimentally difficult methods.

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Sex differences in blood pressure regulation during ischemic isometric exercise: the role of the β-adrenergic receptors

Journal of Applied Physiology ◽

10.1152/japplphysiol.00270.2019 ◽

2019 ◽

Vol 127 (2) ◽

pp. 408-414 ◽

Cited By ~ 4

Author(s):

Milena Samora ◽

Anthony V. Incognito ◽

Lauro C. Vianna

Keyword(s):

Blood Pressure ◽

Sex Differences ◽

Cardiac Output ◽

Total Peripheral Resistance ◽

Adrenergic Receptors ◽

Isometric Exercise ◽

Peripheral Resistance ◽

Blood Pressure Regulation ◽

Pressure Regulation ◽

Β Adrenergic Receptors

We sought to investigate whether the β-adrenergic receptors play a pivotal role in sex-related differences in arterial blood pressure (BP) regulation during isometric exercise. Sixteen volunteers (8 women) performed 2 min of ischemic isometric handgrip exercise (IHE) and 2 min of postexercise circulatory occlusion (PECO). Heart rate (HR) and beat-to-beat arterial BP were continuously measured. Beat-to-beat estimates of stroke volume (ModelFlow) were obtained and matched with HR to calculate cardiac output (Q̇) and total peripheral resistance (TPR). Two trials were randomly conducted between placebo and nonselective β-adrenergic blockade (40 mg propranolol). Under the placebo condition, the magnitude of the BP response in IHE was lower in women compared with men. During PECO, the BP remained elevated and the sex differences persisted. The β-blockade attenuated the BP response during IHE in men (∆57 ± 4 vs. ∆45 ± 7 mmHg, P = 0.025) due to a reduction in Q̇ (∆3.7 ± 0.5 vs. ∆1.8 ± 0.2 L/min, P = 0.012) while TPR was not affected. In women, however, the BP response during IHE was unchanged (∆27 ± 3 vs. ∆28 ± 3 mmHg, P = 0.889), despite attenuated Q̇ (∆2.7 ± 0.4 vs. ∆1.3 ± 0.2 L/min, P = 0.012). These responses were mediated by a robust increase in TPR under β-blockade (∆−0.2 ± 0.4 vs. ∆2.2 ± 0.7 mmHg·L−1·min, P = 0.012). These findings demonstrate that the sex differences in arterial BP regulation during ischemic IHE are mediated by β-adrenergic receptors. NEW & NOTEWORTHY We found that the blood pressure response during isometric exercise in women is mediated by increases in cardiac output, whereas in men it is mediated by increases in both cardiac output and total peripheral resistance. In addition, women showed a robust increase in total peripheral resistance under β-blockade during isometric exercise and muscle metaboreflex activation. These findings demonstrate that sex differences in blood pressure regulation during isometric exercise are mediated by β-adrenergic receptors.

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Hemodynamic monitoring for 24 h in unanesthetized rats

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1987.253.6.h1335 ◽

1987 ◽

Vol 253 (6) ◽

pp. H1335-H1341 ◽

Cited By ~ 12

Author(s):

T. L. Smith ◽

T. G. Coleman ◽

K. A. Stanek ◽

W. R. Murphy

Keyword(s):

Cardiac Output ◽

Mean Arterial Pressure ◽

Cardiac Index ◽

Arterial Pressure ◽

Stroke Volume ◽

Diurnal Variation ◽

Total Peripheral Resistance ◽

Peripheral Resistance ◽

Resistance Index ◽

Total Peripheral Resistance Index

A new technique is described that allows minute-to-minute recordings of cardiac output and arterial pressure in unanesthetized rats for periods of 24 h and longer. Rats were instrumented with electromagnetic flow probes and arterial catheters. An electrical and hydraulic swivel was interposed between the rat and recording apparatus to allow free range of movement. Data were collected and analyzed once each minute by computer. Average 24-h values (mean +/- SD) for the following hemodynamic variables were determined in eight rats [expressed where appropriate as a function of body weight (BW)]: cardiac output (98.1 +/- 14.7 ml/min), cardiac index (29.2 +/- 4.4 ml.min-1.100 g BW-1), mean arterial pressure (92.5 +/- 7.8 mmHg), heart rate (347 +/- 45 beats/min), peak aortic flow (403 +/- 32 ml/min), stroke volume (282 +/- 26 microliters), stroke volume index (84.4 +/- 8.1 microliters/100 g BW), and total peripheral resistance index (3.26 +/- 0.46 mmHg.ml-1.min.100 g BW). These results provide a data base of hemodynamic values for unanesthetized adult, Sprague-Dawley male rats, which has not been previously available. In addition, cardiac index, mean arterial pressure, and total peripheral resistance index demonstrated diurnal variation. Diurnal variation contributed substantially to the overall variance observed within these variables. Hourly variance was also substantial and indicates the use of continuous recordings for short-term experiments.

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Effects of dihydroergotamine on hemodynamic molsidomine actions in anesthetized dogs

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y84-103 ◽

1984 ◽

Vol 62 (6) ◽

pp. 634-639 ◽

Cited By ~ 1

Author(s):

Volker B. Fiedler ◽

Helmut Göbel ◽

Rolf-Eberhard Nitz

Keyword(s):

Heart Rate ◽

Cardiac Output ◽

Stroke Volume ◽

Total Peripheral Resistance ◽

Peripheral Resistance ◽

Left Ventricular ◽

Venous Capacitance ◽

Heart Performance ◽

Dose Dependent Fashion ◽

Anesthetized Dogs

In pentobarbital-anesthetized mongrel dogs the intravenous actions of 0.50 mg/kg molsidomine on pulmonary artery and left ventricular (LV) end-diastolic pressures and internal heart dimensions (preload), left ventricular systolic and peripheral blood pressures, and total peripheral resistance (afterload), as well as on heart rate, dP/dt, stroke volume, and cardiac output (heart performance) were studied for 2 h. Hemodynamic molsidomine effects were influenced by increasing amounts of intravenously infused dihydroergotamine solution (DHE, 1–64 μg∙kg−1∙min−1). Molsidomine decreased preload, stroke volume, and cardiac output for over 2 h but decreased ventricular and peripheral pressures for 45 min. Systemic vascular resistance showed a tendency to decrease while heart rate and LV dP/dtmax were not altered. DHE infusion reversed molsidomine effects on the preload and afterload of the heart. The diminished stroke volume was elevated so that cardiac output also increased. Total peripheral resistance increased while heart rate fell in a dose-dependent fashion. The LV dP/dtmax remained unchanged until the highest dose of 64 μg∙kg−1∙min−1 DHE elevated the isovolumic myocardial contractility. These experiments indicate that DHE can reverse the intravenous molsidomine effects on hemodynamics. Most likely, this is mediated through peripheral vasoconstriction of venous capacitance vessels, thereby affecting moldisomine's action on postcapillary beds of the circulation.

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