Impacto cardiovascular, conducta diagnóstica y terapéutica del feocromocitoma como causa de hipertensión arterial / Cardiovascular impact, diagnostic and therapeutic management of pheochromocytoma as a cause of arterial hypertension

INTRODUCCIÓN. Los feocromocitomas son tumores que provienen de las células neuroendócrinas de la médula adrenal y producen alta secreción de catecolaminas. Generan complicaciones cardiovasculares graves que suelen asociarse con crisis hipertensivas. Es importante valorar el impacto cardiovascular de esta entidad. OBJETIVO. Realizar una revisión exhaustiva de las diversas manifestaciones de los feocromocitomas como causa de hipertensión arterial, su impacto cardiovascular, conducta diagnóstica y terapéutica. MATERIALES Y MÉTODOS. Revisión bibliográfica y análisis de 141 artículos científicos que incluyeron temas sobre el impacto cardiovascular, conducta diagnóstica y terapéutica del feocromocitoma como causa de hipertensión arterial. Se usó bases de datos: Medline, Embase, Scopus, Pubmed, Google Académico. Criterios de búsqueda en DECS, MeSH: "pheochromocytoma OR hypertension arterial AND cardiomyopathy", en inglés- español. Fueron seleccionados: 13 publicaciones de texto completo, 10 artículos retrospectivos, 2 guías de práctica clínica y 1 revisión. Se excluyeron 128 artículos científicos. RESULTADOS. Se realizó una revisión de las manifestaciones clínicas de los feocromocitomas como causa de hipertensión arterial y el impacto cardiovascular se relacionó con la producción de catecolaminas. Para el diagnóstico, la sensibilidad de la resonancia magnética es del 93-100%; la especificidad de resonancia magnética o tomografía computarizada en combinación con gammagrafía con metayodobencilguanidina con 123I es cercana al 100%. La resección del feocromocitoma tiene potencial curativo. CONCLUSIÓN. Los feocromocitomas presentan variabilidad clínica, se asocian a complicaciones cardiovasculares y cerebrovasculares graves por producción de catecolaminas. El diagnóstico oportuno y eficaz debe realizarse mediante resonancia magnética y gammagrafía en caso de alta sospecha clínica. El tratamiento quirúrgico es de elección.

INTRODUCTION. Pheochromocytomas are tumors arising from the neuroendocrine cells of the adrenal medulla and produce high secretion of catecholamines. They generate severe cardiovascular complications that are often associated with hypertensive crises. It is important to assess the cardiovascular impact of this entity. OBJECTIVE. To perform an exhaustive review of the various manifestations of pheochromocytomas as a cause of arterial hypertension, their cardiovascular impact, diagnostic and therapeutic conduct. MATERIALS AND METHODS. Bibliographic review and analysis of 141 scientific articles that included topics on the cardiovascular impact, diagnostic and therapeutic behavior of pheochromocytoma as a cause of arterial hypertension. The following databases were used: Medline, Embase, Scopus, Pubmed, Google Scholar. Search criteria in DECS, MeSH: "pheochromocytoma OR hypertension arterial AND cardiomyopathy", in English-Spanish. The following were selected: 13 full-text publications, 10 retrospective articles, 2 clinical practice guidelines, and 1 review. A total of 128 scientific articles were excluded. RESULTS. A review of the clinical manifestations of pheochromocytoma as a cause of arterial hypertension was performed and the cardiovascular impact was related to catecholamine production. For diagnosis, the sensitivity of MRI is 93-100%; the specificity of MRI or computed tomography in combination with 123I-methiodobenzylguanidine scintigraphy is close to 100%. Resection of pheochromocytoma has curative potential. CONCLUSION. Pheochromocytomas present clinical variability, are associated with severe cardiovascular and cerebrovascular complications due to catecholamine production. Timely and effective diagnosis should be made by MRI and scintigraphy in case of high clinical suspicion. Surgical treatment is the treatment of choice.

Feocromocitoma quístico gigante: reporte de un caso / Pheochromocytoma giant cystic: a case report

El feocromocitoma quístico gigante es tumor adrenal raro en el que predomina el curso asintomático; por lo que muchos de los casos no son diagnosticados hasta el momento de la cirugía. La simple movilización del tumor se asocia con el paso a la sangre de grandes cantidades de catecolaminas y a una elevada morbimortalidad.; por esta razón la cirugía per se y su manejo perioperatorio constituyen un enorme desafío. En este artículo se presenta el caso de un feocromocitoma gigante maligno (35 cm) que ocupaba todo el hemiabdomen derecho. Aun con el diagnóstico preoperatorio de feocromocitoma, el bloqueo farmacológico preoperatorio y las medidas intraoperatorias, el paciente falleció poco antes de que finalizara la cirugía.

The giant cystic pheochromocytoma is a rare adrenal tumor in the predominantly asymptomatic course; so many cases are not diagnosed until the time of surgery. The simple mobilization of the tumor is associated with the passage to the blood of large amounts of catecholamines and high morbidity and mortality. So the surgery itself and perioperative management are a huge challenge. This article describes the case of a malignant giant pheochromocytoma (35 cm) which occupied the entire right abdomen. Even with the preoperative diagnosis of pheochromocytoma, pharmacological blockade preoperative and intraoperative measures, the patient died shortly before the end of surgery.

Left-sided giant adrenal myelolipoma secreting catecholamine.

Adrenal myelolipoma (AML) is a rare benign tumor composed of mature adipose and hematopoietic tissue. Most of these patients are asymptomatic and the tumors are non-secreting. We present a case with a large functional adrenal myelolipoma, wherein the patient was hypertensive and biochemistry revealed increase in 24 hours urinary Vanillylmandelic Acid (VMA), a metabolite of catecholamine. The mass was removed surgically and diagnosed as adrenal myelolipoma on histopathological examination. Both his blood pressure and urinary VMA returned to normal following surgery, which suggested that the mass was functioning and was secreting catecholamine. To the best of our knowledge, a catecholamine secreting adrenal myelolipoma has been reported in the literature only once previously. The association of hypertension and adrenal myelolipoma may not be entirely coincidental, as it may be associated with secreting catecholamine, as seen in our case. We also review the literature on functioning adrenal myelolipoma.

Risk of catecholamine crisis in patients undergoing resection of unsuspected pheochromocytoma

PURPOSE: To report the risk of catecholamine crisis in patients undergoing resection of unsuspected pheochromocytoma. MATERIALS AND METHODS: Over a four-year period, we retrospectively identified four patients who underwent resection of adrenal pheochromocytoma in whom the diagnosis was unsuspected based on preoperative clinical, biochemical, and imaging evaluation. RESULTS: None of the patients exhibited preoperative clinical features of catecholamine excess. Preoperative biochemical screening in two patients was normal. CT scan performed in all patients demonstrated a nonspecific enhancing adrenal mass. During surgical resection of the adrenal mass, hemodynamic instability was observed in two of four patients, and one of these two patients also suffered a myocardial infarct. CONCLUSION: Both surgeons and radiologists should maintain a high index of suspicion for pheochromocytoma, as the tumor can be asymptomatic, biochemically negative, and have nonspecific imaging features. Resection of such unsuspected pheochromocytomas carries a substantial risk of intraoperative hemodynamic instability.

Effect of immobilization stress on gene expression of catecholamine biosynthetic enzymes in heart auricles of socially isolated rats

Chronic stress is associated with the development of cardiovascular diseases. The sympathoneural system plays an important role in the regulation of cardiac function both in health and disease. In the present study, the changes in gene expression of the catecholamine biosynthetic enzymes tyrosine hydroxylase (TH), dopamine-â-hydroxylase (DBH) and phenylethanolamine N-methyltransferase (PNMT) and protein levels in the right and left heart auricles of naive control and long-term (12 weeks) socially isolated rats were investigated by Taqman RT-PCR and Western blot analysis. The response of these animals to additional immobilization stress (2 h) was also examined. Long-term social isolation produced a decrease in TH mRNA level in left auricles (about 70 percent) compared to the corresponding control. Expression of the DBH gene was markedly decreased both in the right (about 62 percent) and left (about 81 percent) auricles compared to the corresponding control, group-maintained rats, whereas PNMT mRNA levels remained unchanged. Exposure of group-housed rats to acute immobilization for 2 h led to a significant increase of mRNA levels of TH (about 267 percent), DBH (about 37 percent) and PNMT (about 60 percent) only in the right auricles. Additional 2-h immobilization of individually housed rats did not affect gene expression of these enzymes in either the right or left auricle. Protein levels of TH, DBH and PNMT in left and right heart auricles were unchanged either in both individually housed and immobilized rats. The unchanged mRNA levels of the enzymes examined after short-term immobilization suggest that the catecholaminergic system of the heart auricles of animals previously exposed to chronic psychosocial stress was adapted to maintain appropriate cardiovascular homeostasis.

A Case of Catecholaminergic Polymorphic Ventricular Tachycardia

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a familial cardiac arrhythmia that is related to RYR2 or CASQ2 gene mutation. It occurs in patients with structurally normal heart and causes exercise-emotion-triggered syncope and sudden cardiac death. We experienced a case of CPVT in an 11 year-old female patient who was admitted for sudden cardiovascular collapse. The initial electrocardiogram (ECG) on emergency department revealed ventricular fibrillation. After multiple defibrillations, sinus rhythm was restored. However, recurrent ventricular fibrillation occurred during insertion of nasogastric tube without sedation in coronary care unit. On ECG monitoring, bidirectional ventricular tachycardia occurred with sinus tachycardia and then degenerated into ventricular fibrillation. To our knowledge, there has been no previous case report of CPVT triggered by sinus tachycardia in Korea. Therefore, we report the case as well as a review of the literature.

Catecholamines May Play an Important Role in the Pathogenesis of Transient Mid- and Basal Ventricular Ballooning Syndrome

The exact pathogenesis of transient mid- and basal ventricular ballooning, a new variant of transient left ventricular (LV) ballooning, remains unknown. We report two cases of transient mid- and basal ventricular ballooning associated with catecholamines. These cases suggest that catecholamine-mediated myocardial dysfunction might be a potential mechanism of this syndrome.

The role of hyperventilation: hypocapnia in the pathomechanism of panic disorder

OBJECTIVE: The authors present a profile of panic disorder based on and generalized from the effects of acute and chronic hyperventilation that are characteristic of the respiratory panic disorder subtype. The review presented attempts to integrate three premises: hyperventilation is a physiological response to hypercapnia; hyperventilation can induce panic attacks; chronic hyperventilation is a protective mechanism against panic attacks. METHOD: A selective review of the literature was made using the Medline database. Reports of the interrelationships among panic disorder, hyperventilation, acidosis, and alkalosis, as well as catecholamine release and sensitivity, were selected. The findings were structured into an integrated model. DISCUSSION: The panic attacks experienced by individuals with panic disorder develop on the basis of metabolic acidosis, which is a compensatory response to chronic hyperventilation. The attacks are triggered by a sudden increase in (pCO2) when the latent (metabolic) acidosis manifests as hypercapnic acidosis. The acidotic condition induces catecholamine release. Sympathicotonia cannot arise during the hypercapnic phase, since low pH decreases catecholamine sensitivity. Catecholamines can provoke panic when hyperventilation causes the hypercapnia to switch to hypocapnic alkalosis (overcompensation) and catecholamine sensitivity begins to increase. CONCLUSION: Therapeutic approaches should address long-term regulation of the respiratory pattern and elimination of metabolic acidosis.

OBJETIVO: Os autores apresentam um modelo de transtorno do pânico que se baseia nos efeitos da hiperventilação aguda e crônica, característicos do subtipo respiratório de transtorno do pânico. O modelo é generalizado a partir desses efeitos. Ele integra três características da hiperventilação: a hiperventilação é uma resposta fisiológica à hipercapnia; a hiperventilação pode induzir ataques de pânico; a hiperventilação crônica representa um mecanismo protetor contra os ataques de pânico. MÉTODO: Revisão seletiva da literatura a partir da base de dados Medline. Foram selecionados relatos referentes à inter-relação entre transtorno do pânico, hiperventilação, acidose, alcalose, liberação de catecolaminas e sensibilidade a catecolaminas, sendo os achados estruturados de modo a formar um modelo integrado. DISCUSSÃO: Os ataques de pânico do transtorno do pânico desenvolvem-se com base numa acidose metabólica, que é uma resposta compensatória à hiperventilação crônica. Os ataques são desencadeados por um súbito aumento da pressão parcial de dióxido de carbono (pCO2), quando a acidose (metabólica) latente se manifesta pela acidose hipercápnica. A condição acidótica induz liberação de catecolaminas. A simpaticotonia não pode manifestar-se durante a fase de hipercapnia, pois o baixo pH diminui a sensibilidade às catecolaminas. As catecolaminas podem provocar pânico quando a hipercapnia comuta para uma alcalose hipocápnica devido à supercompensação pela hiperventilação, situação na qual a sensibilidade às catecolaminas liberadas começa a aumentar. CONCLUSÃO: As abordagens terapêuticas deveriam voltar-se para a regulação em longo prazo do padrão respiratório e a eliminação da acidose metabólica.

Effects of stress on catecholamine stores in central and peripheral tissues of long-term socially isolated rats

Both the peripheral sympatho-adrenomedullary and central catecholaminergic systems are activated by various psycho-social and physical stressors. Catecholamine stores in the hypothalamus, hippocampus, adrenal glands, and heart auricles of long-term socially isolated (21 days) and control 3-month-old male Wistar rats, as well as their response to immobilization of all 4 limbs and head fixed for 2 h and cold stress (4°C, 2 h), were studied. A simultaneous single isotope radioenzymatic assay based on the conversion of catecholamines to the corresponding O-methylated derivatives by catechol-O-methyl-transferase in the presence of S-adenosyl-l-(³H-methyl)-methionine was used. The O-methylated derivatives were oxidized to ³H-vanilline and the radioactivity measured. Social isolation produced depletion of hypothalamic norepinephrine (about 18 percent) and hippocampal dopamine (about 20 percent) stores and no changes in peripheral tissues. Immobilization decreased catecholamine stores (approximately 39 percent) in central and peripheral tissues of control animals. However, in socially isolated rats, these reductions were observed only in the hippocampus and peripheral tissues. Cold did not affect hypothalamic catecholamine stores but reduced hippocampal dopamine (about 20 percent) as well as norepinephrine stores in peripheral tissues both in control and socially isolated rats, while epinephrine levels were unchanged. Thus, immobilization was more efficient in reducing catecholamine stores in control and chronically isolated rats compared to cold stress. The differences in rearing conditions appear to influence the response of adult animals to additional stress. In addition, the influence of previous exposure to a stressor on catecholaminergic activity in the brainstem depends on both the particular catecholaminergic area studied and the properties of additional acute stress. Therefore, the sensitivity of the catecholaminergic system to habituation appears to be tissue-specific.

Effects of chronic ethanol treatment on monoamine levels in rat hippocampus and striatum

We studied the effects of ethanol on concentrations of noradrenaline (NE), dopamine (DA) and serotonin (5-HT) and their metabolites in rat hippocampus and striatum. Ethanol (2 or 4 g/kg, po, from a 20 percent aqueous solution) was administered daily to male Wistar rats (4-13 per group) for 30 days and animals were sacrificed 30 min or 48 h after the last administration. Monoamines were measured by HPLC and considered significant at P < 0.05. A 47 percent increase in 5-HT levels was observed in the hippocampus with 4 g/kg ethanol in the 30-min protocol. Ethanol (2 and 4 g/kg) decreased DA (2114.5 ± 126.4 and 1785.1 ± 234.2 ng/g wet tissue, respectively) and 3,4-dihydroxyphenylacetic acid (DOPAC, 1477.6 ± 132.1 and 1218.8 ± 271.7 ng/g wet tissue, respectively) levels, while the higher dose also decreased NE (159.8 ± 13.5), 5-HT (228.0 ± 46.8) and 5-hydroxy-3-indoleacetic acid (5-HIAA, 304.4 ± 37.2 ng/g wet tissue), in the striatum after a 48-h withdrawal as compared to controls (DA: 3063.9 ± 321.3; DOPAC: 2379.6 ± 256.0; NE: 292.8 ± 50.2; 5-HT: 412.4 ± 36.2; 5-HIAA: 703.9 ± 61.4 ng/g wet tissue). In the 30-min protocol, ethanol (2 or 4 g/kg) decreased striatal NE (66 and 70 percent) and DA (50 and 36 percent) levels. On the other hand, increases were seen in 5-HIAA (146 and 153 percent) and 5-HT (59 and 86 percent) levels. Ethanol (2 g/kg, po) increased the homovanillic acid (HVA)/DA ratio (129 percent) in the striatum in the 30-min protocol, while at the higher dose it increased the HVA/DA ratio in the 48-h protocol (61 percent). These results indicate alterations in monoamines, mainly in the striatum, after chronic ethanol, which are influenced by dose and by the length of time after the last drug administration.

Distrés respiratorio. Nuevas perspectivas en el manejo del edema pulmonar / [Respiratory distress. New Perspectives to lung edema treatment]

Acute respiratory distress syndrome (ARDS) is a life threatening condition associated with great morbidity and mortality. it is characterized initially by accumulation of fluid in the alveolar space that impairs alveolar oxygen exchange. Eventually, this syndrome leads to multiorgan failure. Therefore, rapid edema clearance has generally been associated with better outcome in patients with acute respiratory distress syndrome. Clearance of alveolar fluid is driven predominantly by active Na+ transport out of the alveolar space, mediated by increased apical Na(+)-channel and Na-K-ATPase activity. It has been demonstrated that increases in Na-K-ATPase in response to catecholamines in the alveolar epithelium are associated with increased lung edema clearance. The cellular mechanisms involve the recruitment of new Na-K-ATPase molecules to the plasma membrane from intracellular organelles. It also appears that adenovirus-mediated Na-K-ATPase gene transfer and increased Na-K-ATPase expression may provide an alternative and efficient pathway for transient increase in alveolar fluid reabsorption and resolution of pulmonary edema.

Influence of photoperiods on glycemic and adrenal catecholaminergic responses to melatonin administrations in adult male roseringed parakeets, Psittacula krameri Neumann.

Effects of daily (one hour prior to onset of darkness) injection of melatonin (25 micrograms/100 g body wt. for 30 days) on concentrations of blood glucose and adrenal catecholamines were studied in adult male roseringed parakeets, P. krameri under both natural (NP; about 12L:12D) and artificial long (LP; 16L:8D; lights were available in between 0600 and 2200 hrs) or short (SP; 8L:16D; lights were available between 0600 and 1400 hrs) photoperiodic conditions. The results indicate that neither LP, nor SP as such exerts any significant effect on blood glucose titre of control (vehicle of hormone administered) birds. Treatment with melatonin, however, induced hyperglycemia in both NP and LP bird groups, but hypoglycemia in SP birds. Unlike glycemic levels, amount of epinephrine (E) and norepinephrine (NE) in adrenals of control birds exhibited significant changes under altered photoperiods. A decrease in E and an increase in NE were noted in adrenals of both LP and SP birds. Exogenous melatonin in NP birds also caused a decrease in E and concomittant rise in NE levels. On the other hand, treatment of melatonin in both LP and SP bird groups resulted in an increase in the quantity of both E and NE compared to respective values in adrenals of melatonin injected NP birds. However, relative to the amount of E and NE in adrenals of placebo treated LP and SP birds, significant effect of melatonin treatment was observed only in SP birds. The results suggest that influences of exogenous melatonin on the levels of both blood glucose and adrenal catecholamines are largely modulated by short rather than long photoperiods.

Avaliaçäo hormonal e de reflexos cardiovasculares em portadora de falência autonômica pura / Hormonal and cardiovascular reflex assessment in a female patient with pure autonomic failure

We report the case of a 72-year-old female with pure autonomic failure, a rare entity, whose diagnosis of autonomic dysfunction was determined with a series of complementary tests. For approximately 2 years, the patient has been experiencing dizziness and a tendency to fall, a significant weight loss, generalized weakness, dysphagia, intestinal constipation, blurred vision, dry mouth, and changes in her voice. She underwent clinical assessment and laboratory tests (biochemical tests, chest X-ray, digestive endoscopy, colonoscopy, chest computed tomography, abdomen and pelvis computed tomography, abdominal ultrasound, and ambulatory blood pressure monitoring). Measurements of catecholamine and plasmatic renin activity were performed at rest and after physical exercise. Finally the patient underwent physiological and pharmacological autonomic tests that better diagnosed dysautonomia.

Angiogenesis: characterization of a cellular model

Endothelial cell proliferation and differentiation into blood capillaries (i.e., angiogenesis) are essential for growth and development, wound healing, osetogenesis, etc. But abnormal angiogenesis during tumor progression could lead to serious consequences. Angiogenesis is a complex biochemical process, and is often difficult to study the molecular mechanism in vivo due to interference by multitude of factors. Here, I present a non-transformed capillary endothelial cell line as a model which has been extensively characterized morphologically and biochemically to study the fundamentals of the angiogenic process. Studies completed in our laboratory also evidenced that expression of Glc3Man9GlcNAc2-PP-Dol is intricately connected with the balance between the cellular proliferation and apoptosis during angiogenesis.

Biochemical changes in brain catecholamines and serotonin during gastric ulcer induced by cold restraint stress in male albino rats

The present study was undertaken to investigate the chronological effect of cold restraint stress on the profile of biogenic amines [epinephrine, norepinephrine, dopamine and serotonin] in different areas of the brain, which are known to affect gastric function and are critically involved in the stress response [frontal cortex, hypothalamus and hippocampus]. Cold restraint stress was applied to pylorically ligated male albino rats in half hourly increasing duration [5-3 hr]. In the three selected brain areas, cold restraint stress produced a significant decrease in both norepinephrine and epinephrine concentrations and a significant increase in dopamine and serotonin levels. These changes in brain amines were significantly correlated with the increased duration of stress. The relevance of these findings was discussed

Dopaminergic receptor regulates catecholamine release from perfused adrenal medulla

Nicotinic drug is a potent secretogogues for catecholamine from bovine adrenal glands perfused with oxygenated Locke's buffer. However, apomorphine, I IIM, [the dopaminergic agonist] markedly inhibit this catecholamine release by about 40%. Haloperidol 0.5 muM, [the dopaminergic antagonist] reversed the inhibitory effects of apomorphine. These data strongly suggested that, as in the cat, the bovine adrenal modulates the catecholamine cell contains a dopaminergic receptor that modulates the catecholamine secretory process triggered by stimulation of the nicotinic cholinergic receptor. This dopaminergic receptor might be involved in a sympathoadrenal cooperative mechanism