Experiencia en el manejo de feocromocitoma en los últimos 10 años: serie de casos

El feocromocitoma es un tumor productor de catecolaminas. Se describe la experiencia en el diagnóstico, manejo y seguimiento de pacientes con este diagnóstico en una institución de alta complejidad en Cali, Colombia, en los últimos 10 años. Se encontraron 11 casos con diagnóstico de feocromocitoma llevados a cirugía, dos de estos extraadrenal y uno maligno. Fueron asintomáticos 18%, 81% presentaron hipertensión arterial. La evolución posquirúrgica de los pacientes fue favorable, 33% persistieron con hipertensión arterial (HTA) luego de la resección del tumor, requiriendo menor dosis de antihipertensivos. El único caso de malignidad tuvo una respuesta no satisfactoria. A pesar de ser un diagnóstico infrecuente, su abordaje es importante debido a la morbilidad que representa. Las características de nuestra población son similares a lo reportado en la literatura, con baja frecuencia de complicaciones y adecuada respuesta al tratamiento.Abstract Pheochromocytoma is a catecholamine-producing tumor. We describe the experience in the diagnosis, management and monitoring of patients with pheochromocytoma in a highly complex institution in Cali, Colombia, in the last 10 years. We identified 11 cases with diagnosis of pheochromocytoma, who were taken to surgery, being two of these extraadrenal and one of these malignant. 18% were asymptomatic, 81% had hypertension. The postoperative course of patients was favorable, 33% persisted hypertensive after tumor resection, although less doses of blood pressure medication were required. The only case of malignancy had an unsatisfactory response. Despite being a rare diagnosis, the approach is important because morbidity in our population is similar to those reported in the literature, with a low frequency of complications and adequate response to treatment.

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Resonance in a mathematical model of baroreflex control: arterial blood pressure waves accompanying postural stress

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00050.2004 ◽

2005 ◽

Vol 288 (6) ◽

pp. R1637-R1648 ◽

Cited By ~ 36

Author(s):

Peter E. Hammer ◽

J. Philip Saul

Keyword(s):

Blood Pressure ◽

Mathematical Model ◽

Blood Volume ◽

Low Frequency ◽

Pressure Waves ◽

Central Blood Volume ◽

Arterial Baroreflex ◽

Arterial Blood ◽

Gain Margin ◽

The Stability

A mathematical model of the arterial baroreflex was developed and used to assess the stability of the reflex and its potential role in producing the low-frequency arterial blood pressure oscillations called Mayer waves that are commonly seen in humans and animals in response to decreased central blood volume. The model consists of an arrangement of discrete-time filters derived from published physiological studies, which is reduced to a numerical expression for the baroreflex open-loop frequency response. Model stability was assessed for two states: normal and decreased central blood volume. The state of decreased central blood volume was simulated by decreasing baroreflex parasympathetic heart rate gain and by increasing baroreflex sympathetic vaso/venomotor gains as occurs with the unloading of cardiopulmonary baroreceptors. For the normal state, the feedback system was stable by the Nyquist criterion (gain margin = 0.6), but in the hypovolemic state, the gain margin was small (0.07), and the closed-loop frequency response exhibited a sharp peak (gain of 11) at 0.07 Hz, the same frequency as that observed for arterial pressure fluctuations in a group of healthy standing subjects. These findings support the theory that stresses affecting central blood volume, including upright posture, can reduce the stability of the normally stable arterial baroreflex feedback, leading to resonance and low-frequency blood pressure waves.

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Patterns in blood pressure medication use in US incident dialysis patients over the first 6 months

BMC Nephrology ◽

10.1186/1471-2369-14-249 ◽

2013 ◽

Vol 14 (1) ◽

Cited By ~ 21

Author(s):

Wendy L St Peter ◽

◽

Stephen M Sozio ◽

Tariq Shafi ◽

Patti L Ephraim ◽

...

Keyword(s):

Blood Pressure ◽

Medication Use ◽

Blood Pressure Medication ◽

Dialysis Patients

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Abstract P262: Resequencing Study Identifies Epithelial Sodium Channel Genes and Novel Low Frequency Variants Associated with Blood Pressure Salt-sensitivity: The GenSalt Study

Circulation ◽

10.1161/circ.133.suppl_1.p262 ◽

2016 ◽

Vol 133 (suppl_1) ◽

Author(s):

Christopher E Anderson ◽

Changwei Li ◽

Jiang He ◽

Dongfeng Gu ◽

Dabeeru C Rao ◽

...

Keyword(s):

Blood Pressure ◽

Family Structure ◽

Sodium Channel ◽

Association Studies ◽

Low Frequency ◽

Epithelial Sodium Channel ◽

Salt Sensitivity ◽

Minor Allele ◽

Indicator Variable ◽

High Sodium

Christopher E. Anderson, Changwei Li, Jiang He, Dongfeng Gu, Dabeeru C. Rao, James E. Hixson, Lawrence C. Shimmin, Jianfeng Huang, Charles C. Gu, Jichun Chen, Jianxin Li, Tanika N. Kelly Genetic association studies have identified significant associations between common variants from the epithelial sodium channel (ENaC) genes and blood pressure responses to dietary sodium interventions. The roles of low-frequency and rare ENaC variants in blood pressure salt-sensitivity remain largely unexplored. To test this hypothesis, we conducted an ENaC candidate gene resequencing study among participants in the Genetic Epidemiology Network of Salt-Sensitivity (GenSalt). The GenSalt study was conducted among 1,906 participants from 633 families who underwent a 7-day low-sodium (51.3 mmol sodium/day) followed by a 7-day high-sodium (307.8 mmol sodium/day) feeding-study. We chose the 300 GenSalt subjects with the highest and 300 GenSalt subjects with the lowest mean arterial pressure responses to the high sodium intervention to participate in the current resequencing study. Functional regions of three ENaC subunit genes ( SCNN1A , SCNN1B and SCNN1G ) were resequenced using the VariantSEQr TM system (Applied Biosystems; Foster City, CA). For gene-based analyses, variants with MAF less than 5% were first collapsed within each ENaC gene. The collapsed indicator variable was then tested for association with blood pressure salt-sensitivity using generalized estimating equations (GEE) to accommodate correlation of genotypes due to family structure and adjust for the fixed effects of age, gender and field center. Single variant analyses were performed for all low-frequency variants with a minor allele frequency (MAF) greater than 1% and less than 5%, again using GEE to accommodate family structure and adjust for covariables. We did not identify any associations between ENaC genes and blood pressure salt-sensitivity in the gene-based analyses. However, single variant analysis identified a novel association between a low-frequency variant in SCNN1G , rs148083677, and blood pressure salt-sensitivity (P=0.02). Each minor allele was associated with 71% lower odds of blood pressure salt-sensitivity. Although replication studies are needed, these findings provide promising evidence of a role for low-frequency ENaC variants in blood pressure salt-sensitivity.

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Carotid and aortic baroreflexes of the rat: II. Open-loop frequency response and the blood pressure spectrum

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.2000.279.5.r1922 ◽

2000 ◽

Vol 279 (5) ◽

pp. R1922-R1933 ◽

Cited By ~ 20

Author(s):

Barry R. Dworkin ◽

Xiaorui Tang ◽

Alan J. Snyder ◽

Susan Dworkin

Keyword(s):

Blood Pressure ◽

Venous Pressure ◽

Low Frequency ◽

Noise Spectrum ◽

Open Loop ◽

Step Response ◽

Algebraic Solution ◽

Noise Power ◽

Vascular Conductance ◽

Aortic Depressor Nerve

To determine the relationship between blood pressure (BP) variability and the open-loop frequency domain transfer function (TF) of the baroreflexes, we measured the pre- and postsinoaortic denervation (SAD) spectra and the effects of periodic and step inputs to the aortic depressor nerve and isolated carotid sinus of central nervous system-intact, neuromuscular-blocked (NMB) rats. Similar to previous results in freely moving rats, SAD greatly increased very low frequency (VLF) (0.01–0.2 Hz) systolic blood pressure (SBP) noise power. Step response-frequency measurements for SBP; interbeat interval (IBI); venous pressure; mesenteric, femoral, and skin blood flow; and direct modulation analyses of SBP showed that only VLF variability could be substantially attenuated by an intact baroreflex. The −3-dB frequency for SBP is 0.035–0.056 Hz; femoral vascular conductance is similar to SBP, but mesenteric vascular conductance has a reliably lower and IBI has a reliably higher −3-dB point. The overall open-loop transportation lag, of which ≤0.1 s is neural, is ≈1.07 s. Constrained algebraic solution, over a range of frequencies, of the pre- and postSAD endogenous noise spectra and the independently determined relative frequency and absolute lag measurements was used to calculate the absolute gain for the open-loop TF. The average gain at 0.02 Hz, the frequency of maximum sensitivity, was 1.47 (95% confidence interval = ±0.48), which agrees well with estimates for the dog reversible sinus. We found that, in the NMB rat, the effects of SAD on the BP noise spectrum were accounted for by the open-loop properties of the baroreflex.

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Comparative study on effect of neutral spinal bath and neutral spinal spray on blood pressure, heart rate and heart rate variability in healthy volunteers

Journal of Complementary and Integrative Medicine ◽

10.1515/jcim-2018-0118 ◽

2018 ◽

Vol 16 (2) ◽

Author(s):

Arundhati Goley ◽

A. Mooventhan ◽

NK. Manjunath

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Heart Rate Variability ◽

Healthy Volunteers ◽

Group Analysis ◽

Low Frequency ◽

Single Session ◽

Arterial Blood ◽

Before And After ◽

Instantaneous Heart Rate

Abstract Background Hydrotherapeutic applications to the head and spine have shown to improve cardiovascular and autonomic functions. There is lack of study reporting the effect of either neutral spinal bath (NSB) or neutral spinal spray (NSS). Hence, the present study was conducted to evaluate and compare the effects of both NSB and NSS in healthy volunteers. Methods Thirty healthy subjects were recruited and randomized into either neutral spinal bath group (NSBG) or neutral spinal spray group (NSSG). A single session of NSB, NSS was given for 15 min to the NSBG and NSSG, respectively. Assessments were taken before and after the interventions. Results Results of this study showed a significant reduction in low-frequency (LF) to high-frequency (HF) (LF/HF) ratio of heart rate variability (HRV) spectrum in NSBG compared with NSSG (p=0.026). Within-group analysis of both NSBG and NSSG showed a significant increase in the mean of the intervals between adjacent QRS complexes or the instantaneous heart rate (HR) (RRI) (p=0.002; p=0.009, respectively), along with a significant reduction in HR (p=0.002; p=0.004, respectively). But, a significant reduction in systolic blood pressure (SBP) (p=0.037) and pulse pressure (PP) (p=0.017) was observed in NSSG, while a significant reduction in diastolic blood pressure (DBP) (p=0.008), mean arterial blood pressure (MAP) (p=0.008) and LF/HF ratio (p=0.041) was observed in NSBG. Conclusion Results of the study suggest that 15 min of both NSB and NSS might be effective in reducing HR and improving HRV. However, NSS is particularly effective in reducing SBP and PP, while NSB is particularly effective in reducing DBP and MAP along with improving sympathovagal balance in healthy volunteers.

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Effect of heavy exercise on spectral baroreflex sensitivity, heart rate, and blood pressure variability in well-trained humans

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00003.2008 ◽

2008 ◽

Vol 295 (3) ◽

pp. H1150-H1155 ◽

Cited By ~ 24

Author(s):

François Cottin ◽

Claire Médigue ◽

Yves Papelier

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Systolic Blood Pressure ◽

Exercise Test ◽

Blood Pressure Variability ◽

Baroreflex Sensitivity ◽

Low Frequency ◽

Mechanical Effect ◽

Heavy Exercise ◽

Gas Exchange Parameters

The aim of the study was to assess the instantaneous spectral components of heart rate variability (HRV) and systolic blood pressure variability (SBPV) and determine the low-frequency (LF) and high-frequency baroreflex sensitivity (HF-BRS) during a graded maximal exercise test. The first hypothesis was that the hyperpnea elicited by heavy exercise could entail a significant increase in HF-SBPV by mechanical effect once the first and second ventilatory thresholds (VTs) were exceeded. It was secondly hypothesized that vagal tone progressively withdrawing with increasing load, HF-BRS could decrease during the exercise test. Fifteen well-trained subjects participated in this study. Electrocardiogram (ECG), blood pressure, and gas exchanges were recorded during a cycloergometer test. Ventilatory equivalents were computed from gas exchange parameters to assess VTs. Spectral analysis was applied on cardiovascular series to compute RR and systolic blood pressure power spectral densities, cross-spectral coherence, gain, and α index of BRS. Three exercise intensity stages were compared: below (A1), between (A2), and above (A3) VTs. From A1 to A3, both HF-SBPV (A1: 45 ± 6, A2: 65 ± 10, and A3: 120 ± 23 mm2Hg, P < 0.001) and HF-HRV increased (A1: 20 ± 5, A2: 23 ± 8, and A3:40 ± 11 ms2, P < 0.02), maintaining HF-BRS (gain, A1: 0.68 ± 0.12, A2: 0.63 ± 0.08, and A3: 0.57 ± 0.09; α index, A1: 0.58 ± 0.08, A2: 0.48 ± 0.06, and A3: 0.50 ± 0.09 ms/mmHg, not significant). However, LF-BRS decreased (gain, A1: 0.39 ± 0.06, A2: 0.17 ± 0.02, and A3: 0.11 ± 0.01, P < 0.001; α index, A1: 0.46 ± 0.07, A2: 0.20 ± 0.02, and A3: 0.14 ± 0.01 ms/mmHg, P < 0.001). As expected, once VTs were exceeded, hyperpnea induced a marked increase in both HF-HRV and HF-SBPV. However, this concomitant increase allowed the maintenance of HF-BRS, presumably by a mechanoelectric feedback mechanism.

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Myocardial123I-MIBG Uptake and Cardiovascular Autonomic Function in Parkinson’s Disease

Parkinson s Disease ◽

10.1155/2015/805351 ◽

2015 ◽

Vol 2015 ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

Akira Katagiri ◽

Masato Asahina ◽

Nobuyuki Araki ◽

Anupama Poudel ◽

Yoshikatsu Fujinuma ◽

...

Keyword(s):

Blood Pressure ◽

Parkinson’S Disease ◽

Parkinson's Disease ◽

Autonomic Function ◽

Low Frequency ◽

Washout Rate ◽

Tilt Test ◽

Mibg Uptake ◽

Cardiovascular Autonomic Function ◽

Frequency Power

Introduction. Patients with Parkinson’s disease (PD) showed reduced myocardial123I-MIBG uptake, which may affect autonomic regulation. We investigated correlation between MIBC accumulation and cardiovascular autonomic function in PD.Methods. We performed myocardial MIBG scintigraphy, heart rate variability (HRV) analysis, and the head-up tilt test (HUT) in 50 PD patients (66.4±7.8years; duration5.5±5.9years). Autonomic function tests were also performed in 50 healthy controls (66.5±8.9years). As HRV parameters, a high-frequency power (HF, 0.15–0.4 Hz), a low-frequency power (LF, 0.04–0.15 Hz), and LF/HF ratio were used.Results. Our PD patients had a significant reduction in LF and HF compared with the controls (P=0.005andP=0.01). In HUT, systolic and diastolic blood pressure falls in the PD group were significantly greater than those in the controls (P=0.02andP=0.02). The washout rate of MIBG was negatively correlated with blood pressure changes during HUT.Conclusion. Our PD patients showed reduced HRV, blood pressure dysregulation, and reduced MIBG accumulation, which was correlated with blood pressure dysregulation. Orthostatic hypotension in PD may be mainly caused by sympathetic postganglionic degeneration.

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Use of the train-of-five bipolar technique to provide reliable, spatially accurate motor cortex identification in asleep patients

Neurosurgical FOCUS ◽

10.3171/2019.11.focus19776 ◽

2020 ◽

Vol 48 (2) ◽

pp. E4 ◽

Cited By ~ 2

Author(s):

Evan D. Bander ◽

Evgeny Shelkov ◽

Oleg Modik ◽

Padmaja Kandula ◽

Steven C. Karceski ◽

...

Keyword(s):

Motor Cortex ◽

High Frequency ◽

Tumor Resection ◽

Low Frequency ◽

Retrospective Chart Review ◽

High Frequency Stimulation ◽

Language Mapping ◽

Motor Mapping ◽

Additional Tool ◽

Bipolar Stimulation

OBJECTIVEIntraoperative cortical and subcortical mapping techniques have become integral for achieving a maximal safe resection of tumors that are in or near regions of eloquent brain. The recent literature has demonstrated successful motor/language mapping with lower rates of stimulation-induced seizures when using monopolar high-frequency stimulation compared to traditional low-frequency bipolar stimulation mapping. However, monopolar stimulation carries with it disadvantages that include more radiant spread of electrical stimulation and a theoretically higher potential for tissue damage. The authors report on the successful use of bipolar stimulation with a high-frequency train-of-five (TOF) pulse physiology for motor mapping.METHODSBetween 2018 and 2019, 13 patients underwent motor mapping with phase-reversal and both low-frequency and high-frequency bipolar stimulation. A retrospective chart review was conducted to determine the success rate of motor mapping and to acquire intraoperative details.RESULTSThirteen patients underwent both high- and low-frequency bipolar motor mapping to aid in tumor resection. Of the lesions treated, 69% were gliomas, and the remainder were metastases. The motor cortex was identified at a significantly greater rate when using high-frequency TOF bipolar stimulation (n = 13) compared to the low-frequency bipolar stimulation (n = 4) (100% vs 31%, respectively; p = 0.0005). Intraoperative seizures and afterdischarges occurred only in the group of patients who underwent low-frequency bipolar stimulation, and none occurred in the TOF group (31% vs 0%, respectively; p = 0.09).CONCLUSIONSUsing a bipolar wand with high-frequency TOF stimulation, the authors achieved a significantly higher rate of successful motor mapping and a low rate of intraoperative seizure compared to traditional low-frequency bipolar stimulation. This preliminary study suggests that high-frequency TOF stimulation provides a reliable additional tool for motor cortex identification in asleep patients.

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Age dependency of cardiovascular autonomic responses to head-up tilt in healthy subjects

Journal of Applied Physiology ◽

10.1152/japplphysiol.00444.2003 ◽

2004 ◽

Vol 96 (6) ◽

pp. 2333-2340 ◽

Cited By ~ 105

Author(s):

Tomi Laitinen ◽

Leo Niskanen ◽

Ghislaine Geelen ◽

Esko Länsimies ◽

Juha Hartikainen

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

High Frequency ◽

Healthy Subjects ◽

Baroreflex Sensitivity ◽

Low Frequency ◽

Upright Position ◽

Vascular Responses ◽

Autonomic Responses ◽

Head Up Tilt

In elderly subjects, heart rate responses to postural change are attenuated, whereas their vascular responses are augmented. Altered strategy in maintaining blood pressure homeostasis during upright position may result from various cardiovascular changes, including age-related cardiovascular autonomic dysfunction. This exploratory study was conducted to evaluate impact of age on cardiovascular autonomic responses to head-up tilt (HUT) in healthy subjects covering a wide age range. The study population consisted of 63 healthy, normal-weight, nonsmoking subjects aged 23–77 yr. Five-minute electrocardiogram and finger blood pressure recordings were performed in the supine position and in the upright position 5 min after 70° HUT. Stroke volume was assessed from noninvasive blood pressure signals by the arterial pulse contour method. Heart rate variability (HRV) and systolic blood pressure variability (SBPV) were analyzed by using spectral analysis, and baroreflex sensitivity (BRS) was assessed by using sequence and cross-spectral methods. Cardiovascular autonomic activation during HUT consisted of decreases in HRV and BRS and an increase in SBPV. These changes became attenuated with aging. Age correlated significantly with amplitude of HUT-stimulated response of the high-frequency component ( r = -0.61, P < 0.001) and the ratio of low-frequency to high-frequency power of HRV ( r = -0.31, P < 0.05) and indexes of BRS (local BRS: r = -0.62, P < 0.001; cross-spectral baroreflex sensitivity in the low-frequency range: r = -0.38, P < 0.01). Blood pressure in the upright position was maintained well irrespective of age. However, the HUT-induced increase in heart rate was more pronounced in the younger subjects, whereas the increase in peripheral resistance was predominantly observed in the older subjects. Thus it is likely that whereas the dynamic capacity of cardiac autonomic regulation decreases, vascular responses related to vasoactive mechanisms and vascular sympathetic regulation become augmented with increasing age.

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