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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cardiac enlargement and dysfunction are common in patients with acromegaly. Whether these changes are a direct consequence of growth hormone excess is obscured by the high frequency of hypertension, diabetes mellitus, or atherosclerosis in acromegalic patients. In this study, the effects of chronic elevations of growth hormone (GH) upon the heart were studied in rats with GH-producing tumours implanted subcutaneously for 4 weeks. Geometric measurements and histology were employed to detect the presence of cardiac changes. Increased mass was observed in the tumour-bearing animals. When compared with controls, in tumour-bearing rats there were significantly greater (P less than 0.05) right (0.17 +/- 0.03 v. 0.13 +/- 0.01 g) and left (0.62 +/- 0.05 v. 0.50 +/- 0.04 g) ventricular weights, external cardiac dimensions, and myocardial fibre diameters (9.4 +/- 0.6 v. 8.3 +/- 0.4 micron). However, these increases were linearly-related to increased body mass in the tumour-bearing group so that the ratios of ventricular weights to body weight were similar in both groups. Furthermore, no pathologic changes such as myocardial fibrosis or asymmetric septal hypertrophy were present in the tumour-bearing rats. Thus, under the conditions of this study, growth hormone excess induced cardiac growth, which appeared to represent a manifestation of generalized body growth rather than a distinct pathologic process.
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PMID:Cardiac morphology in rats with growth hormone-producing tumours. 293 34

We herein report the case of a 53-year-old white acromegalic patient with an abdominal mass due to massive cardiomegaly. The patient suffered from long lasting acromegaly refractary to bromocriptine, transsphenoidal surgery and radiotherapy. He had been previously diagnosed as having systemic hypertension, ischemic chest pain and congestive heart failure with marked cardiomegaly. The present admission was due to asthenia, anorexia and weight loss that were finally attributed to adrenal insufficiency secondary to radiotherapy. Plain abdomen X-ray suggested the presence of supramesocolic mass. A large cold area in the left hepatic lobe was detected on the radionuclide liver scan. Radionuclide angiography surprisingly identified the cold area as a vascular structure corresponding to the heart. A body CT scan revealed the heart was expanding between stomach and liver. Two-dimensional echocardiography showed marked enlargement of left ventricle. Cardiomegaly was probably multifactorial (chronic hypertension, ischemic heart disease and acromegaly). To our knowledge, this is the first reported case of massive cardiomegaly behaving as an intraabdominal mass. This possibility must be considered when invasive intraabdominal diagnostic procedures are to be done, particularly in an acromegalic patient.
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PMID:Cardiomegaly and abdominal mass in an acromegalic patient. 296 77

Circulating inhibitors of the Na+ pump have been proposed as participating in sodium excretion, extracellular and vascular volume regulation and as hypertensiogenic agents. The presence of digitalis-like compounds in human plasma has been investigated by measuring its ability to compete with tritiated ouabain for binding to the digitalis site of red blood cells. Their activities in plasma from either hypertensive or volume expanded patients were compared. High levels were found in plasma from 37 p. cent of the untreated patients with essential hypertension, 64 p. cent of patients with end-stage renal failure and 71 p cent of acromegalic patients in the hypersecreting phase. The patients of these two last classes have been selected as being normotensives and without family history of hypertension. An increased activity of the inhibitor should more likely be linked to the positive Na+ balance and the volemic expansion which characterise these last two diseases than to high blood pressure. The observations that the activity of the inhibitor is correlated with the plasma volume in acromegalic patients, it returns to normal values after hemodialysis in renal insufficiency or successful therapy of acromegaly and the decrease in its activity is proportional to the weight lost during dialysis in uremic patients, agree with this proposal.
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PMID:[Circulating inhibitor of sodium active transport in essential hypertension and volemic expansion]. 300 21

There is increasing evidence for endogenous, circulating compounds that interact with the digitalis receptor of [Na,K]ATPase and with antidigoxin antisera. Circulating levels of these digitalis-like compounds increase in response to fluid or salt loading and appear to play a role in diseases characterized by fluid and salt retention, e.g. renal failure, liver disease, acromegaly, experimental and human hypertension, and preeclampsia. Because of assay nonspecificity, many diverse substances are being measured. Of the few compounds currently identified as having "digitalis-like" activity, none appears to be the natural ligand of the digitalis receptor and none appears linked with hypertension. Nevertheless, research still suggests that digitalis-like factors may have a central role in essential hypertension and related disorders.
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PMID:Endogenous digitalis-like natriuretic factors. 303 37

The authors report 3 cases of acromegaly diagnosed while the patients were in hospital for cardiovascular disease: arterial hypertension in two and hypertrophic myocardiopathy in all three. Coronary arteriography was normal in the 3 patients. The exercise-induced dyspnoea observed in these 3 cases was unexplained by right and left cardiac catheterization results (normal pressures, normal or increased cardiac index). It was most probably related to the myocardial hypertrophy and to abnormalities in diastolic function demonstrated by radioisotopic methods in patients 2 and 3. The degree of myocardial hypertrophy present in these 3 patients seemed to correlate with the size of the pituitary adenoma and the plasma level of growth hormone rather than with the duration or degree of arterial hypertension. After excision of the pituitary adenoma hypertension persisted in 1 case, due to associated adrenal gland hyperplasia, and subsided in the other cases. Abnormalities of diastolic function and dyspnoea are gradually regressing but left ventricular hypertrophy has not significantly decreased after 6 post-operative months.
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PMID:[Cardiovascular involvement in acromegaly. Apropos of 3 cases]. 312 8

M-mode echocardiography was used to study cardiac involvement in 78 patients with acromegaly. Proportionate concentric or eccentric left ventricular hypertrophy (LVH) was a common finding. Calculated left ventricular mass (LVM) was increased significantly in a hormonally active disease group compared to an inactive disease group or a control group (153 +/- 7 vs. 96 +/- 8 and 89 +/- 3 g/m2 resp.; p less than 0.001 for both). The increase of LVM in hormonally active disease is due to predominantly LV dilatation, whereas associated hypertension, if present, aggravates the LVH exclusively due to thickening of the LV wall. Hypocorticalism, if present, does not influence the degree of LVH. Asymmetric septal hypertrophy was not found to be specific for acromegaly and was seen in only 7.7% of patients. There was no correlation between LVM and both the plasma levels of growth hormone and duration of disease. On the basis of a retrospective analysis of LVM in successfully treated patients the authors conclude that specific heart muscle disease in acromegaly, manifesting itself as LVH, is slowly reversible after cessation of the growth hormone hyperproduction.
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PMID:The nature of cardiac hypertrophy in acromegaly: an echocardiographic study. 316 77

The epidemiologic link between obesity and hypertension is more clearly emerging to be one between insulin resistance and hypertension. Relative insulin resistance occurs not only in obese hypertensive patients but also in non-obese lean essential hypertensive patients. Although insulin has complex actions on the circulation, plausible mechanisms by which insulin might raise blood pressure include renal sodium retention and stimulation of the sympathetic nervous system. However, the evidence that insulin can actually raise blood pressure in the long-term is lacking. Since hypertension does not develop in all obese or insulin-resistant subjects, the relationship must be modulated by other genetic or environmental factors. Obesity, diminished physical conditioning, aging, and diabetes are ubiquitous contributors to relative insulin resistance and all are associated with a tendency for blood pressure to rise. Conditions and agents associated with acquired insulin resistance and secondary forms of hypertension include pregnancy, oral contraceptives, acromegaly, and glucocorticoids. Although type 2 non-insulin-dependent diabetes is a state of increased insulin resistance, hypertension is partly sustained by secondary renal mechanisms. Future research should identify the genetic and environmental determinants of insulin resistance in hypertension and utilize these in therapy.
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PMID:The enigma of insulin resistance and hypertension. Insulin resistance, blood pressure, and the circulation. 327 70

A personal series of 256 cases of acromegaly/gigantism seen over a 20-year period from 1963 is described. The insidious nature of the condition resulted in delay in diagnosis which was often made by a doctor when seeing the patient for an unrelated problem. Other features which commonly led to the diagnosis being made were headache, change in appearance, carpal tunnel syndrome, amenorrhoea and diabetes. The Hardy system for grading the radiological appearance of the pituitary tumour was used. Widely invasive tumours were not common but tended to occur in patients with younger age of onset and high GH levels. The occurrence of various symptoms and clinical features was noted and the changes resulting from reducing the GH level to normal. The incidence of hypertension, but not of coronary artery disease, is increased and the blood pressure may be reduced following successful treatment. The effects on the upper and lower respiratory tract are reported as well as sleep apnoea and problems associated with anaesthesia. Skin manifestations included sweating, pigmented skin tags, acanthosis nigricans and cutis verticis gyrata. In the skeletal system the incidence of kyphoscoliosis and osteoarthritis especially of the hip is reported: the question of hip replacement is discussed. Diabetes mellitus disappeared in most cases if the acromegaly was cured. In men but not in women the incidence of colloid nodular goitre was increased as was hyperthyroidism in middle-aged women. In two patients a parathyroid adenoma was present: hypercalcaemia was present in five additional patients, but the cause was not determined. The common occurrence of amenorrhoea in the younger women was noted, it was not always associated with hyperprolactinaemia, and often responded to successful treatment of the acromegaly. The association of acromegaly with hirsutism and galactorrhoea is confirmed. The incidence of impotence and loss of libid in the men is discussed: in a proportion of those in whom the acromegaly was cured, potency returned, but in a number depression occurred and what was believed to be psychogenic impotence persisted. Hyperprolactinaemia was found in 49 out of 151 patients with active acromegaly in whom the prolactin level was measured. Previous reports have indicated a doubling of death rates in acromegalics. In this series there were 47 deaths observed compared to 37.2 expected. The increased death rate was in women of all ages and in men under the age of 55, The increased deaths in the women were from cardiovascular and cerebrovascular causes and from breast cancer.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Acromegaly. 330 90

Acromegaly is caused by GH-secreting pituitary adenomas and, in rare cases, by ectopic production of GRH with resultant hypersecretion of GH. Important systemic manifestations include acral enlargement, swelling, disfigurement, glucose intolerance and diabetes, hypertension, nerve entrapment, arthropathy, and cardiac disease. Tumor-related major manifestations are visual impairment, oculomotor paralysis, and hypopituitarism. Morbidity is substantial, and mortality is increased. Diagnosis should be made as early as possible by measuring plasma GH after an oral glucose load and plasma somatomedin C levels. Assessment of a pituitary lesion is best made by CT scanning in the coronal plane. Therapy is mandatory and consists of surgical removal of the pituitary adenoma (usually by the transsphenoidal route) or of the ectopic source of GRH (carcinoids or islet cell tumors). Adjunctive radiation and/or drug therapy is often necessary if complete surgical ablation of the adenoma is not possible. Radiation therapy can be administered as conventional supervoltage x-ray treatment or in the form of heavy particle beams. Drugs effective in partially lowering GH levels are bromocriptine and (not yet released) somatostatin analogues. Long-term follow-up of treated patients is important to guard against recurrence, progression, or development of hypopituitarism.
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PMID:Acromegaly. 331 99

Cardiac function was studied by echocardiography in 12 patients with active acromegaly and in 12 age- and sex-matched healthy control subjects. None of the patients had cardiovascular diseases or other endocrine diseases than acromegaly. The patients had a mean age of 39 +/- 5 years and were short-term acromegalic with a mean duration of disease of 6 +/- 3 years. Mean left ventricular mass was 163 +/- 43 g/m2 in the acromegalic group versus 120 +/- 24 g/m2 in the control group. Preload (the diastolic diameter of the left ventricle) was within normal limits, while afterload (end-systolic meridional wall stress) was significantly decreased in the acromegalic group. Myocardial contractility assessed as fractional shortening of the left ventricle was 39.9 +/- 3.6% in the acromegalic group versus 32.9 +/- 5.1% in the control group, and cardiac output was increased by 52% in the acromegalic group because of increased heart rate and stroke volume. We suggest that augmented peripheral blood flow is responsible for the condition of cardiac hyperkinesia in short-term acromegaly and involved in the development of hypertension, which is a frequent complication of long-term acromegaly.
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PMID:A hyperkinetic heart in uncomplicated active acromegaly. Explanation of hypertension in acromegalic patients? 336 14


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