Hypertension results

Chapter 3 describes the 1-benzazepine family, particularly in relation to their use in the treatment of certain forms of hypertension resulting from inhibition of angiotensin-converting enzymes. In Chapter 4, regulation of the role of mast cells in the control of the microenvironment, and tissue growth and repair by many endogenous peptides is reviewed. 

Ephedrine may cause hypertension resulting in intracranial hemorrhage. It may induce anginal pain in patients with coronary insufficiency or ischemic heart disease. Large doses of inhaled or oral salmeterol (12 to 20 times the recommended dose) have been associated with clinically significant prolongation of the QTc interval, which has the potential for producing ventricular arrhythmias. 

Ramipril in patients with mild to moderate hypertension results in a reduction of both supine and standing blood pressure. In patients of acute myocardial infarction with CHE, ramipril reduced total mortality, progression of heart failure and CHF-related hospitalizations. 

Hypertension is defined as a sustained diastolic blood pressure greater than 90 mm Hg accompanied by an elevated systolic blood pressure (>140 mm Hg). Hypertension results from increased peripheral vascular smooth muscle tone, which leads to increased arteriolar resistance and reduced capacitance of the venous system. Elevated blood pressure is an extremely common disorder, affecting approximately 15% of the population of the United States (60 million people). Although many of these individuals have no symptoms, chronic hypertension—either systolic or diastolic—can lead to congestive heart failure, myocardial infarction, renal damage, and cerebrovascular accidents. The incidence of morbidity and mortality significantly decreases when hypertension is diagnosed early and is properly treated. 

In seven cases of poisoning with phencyclidine, death followed a hypertensive crisis (9). In one case an acute episode of hypertension resulted in coma and blindness (10). 

Interactions. With nonselective monoamine oxidase inhibitors (MAOI), the monoamine dopamine formed from levodopa is protected from destruction it accumulates and also follows the normal path of conversion to noradrenaline (norepinephrine), by dopamine (J-hydroxylase severe hypertension results. The interaction with the selective MAO-B inhibitor, selegiline, is possibly therapeutic (see below). Tricyclic antidepressants are safe. Levodopa antagonises the effects of antipsychotics (dopamine receptor blockers). Some antihypertensives enhance hypotensive effects of levodopa. Metabolites of dopamine in the urine interfere with some tests for phaeochromocytoma, and in such patients it is best to measure the plasma catecholamines directly. 

Fig. 14.3 Smooth cirrhosis with smooth surface and portal hypertension resulting from chronic vitamin A intoxication (same patient as in fig. 14.2)...

Koenig W. Comparison of the efficacy and tolerability of combination tablets containing candesartan cilexetU or losartan and hydrochlorothiazide in patients with moderate to severe hypertension. Results of the CARLOS-Study. Clin Drug Invest 2000 19 239 6. 

Shepherd PC, Fooks J, Gray R, Allan NC. Thioguanine used in maintenance therapy of chronic myeloid leukaemia causes non-cirrhotic portal hypertension. Results from MRC CML. II. Trial comparing busulphan with busulphan and thioguanine. Br I Haematol 1991 79(2) 185-92. 

D Alonzo GE, Barst RJ, Ayres SM, et al. Survival in patients with primary pulmonary hypertension. Results from a national prospective registry. Ann Intern Med 1991 115(5) 343-9. 

Galie N, Olschewski H, Oudiz R, et al. Ambrisentan for the treatment of pulmonary arterial hypertension results of the ambrisentan in pulmonary arterial hypertension. Randomized, double-blind, placebo-controlled, multicenter, efficacy (ARIES) study 1 and 2. Circulation 2008 117(23) 3010-19. 

Hypertension results from an increase in transniural pressure across the vessel wall. The primary determinants of vascular tension are the more muscular arterioles, which are able to change diameter and thus change resistance. Thus, total peripheral resistance (TPR) is the primary determinant of hypertension. The amount of fluid within the vessels is also a determinant. Therefore, cardiac output and blood (fluid) volume are also determinants. Recall also that cardiac output = heart rate x force of contraction and is influenced by preload (venous tone) and afterload (arterial tone). 

B. Do not use as single therapy for hypertension resulting from sympathomimetic overdose. Propranolol produces peripheral vascular beta-blockade, which may abolish beta-2-mediated vasodilation and allow unopposed alpha-mediated vasoconstriction, resulting in paradoxic worsening of hypertension. 

Bodin T, Albin M, Ardo J, Stroh E, Osteigren PO, Bjork J (2009) Road traffic noise and hypertension results fiom a cross-sectional public health survey in southern Sweden. Environ Health 8 38... 

Beghetti M, Hoeper MM, Kiely DG, Carlsen J, Schwierin B, Segal ES, Humbert M. Safety experience with bosentan in 146 children 2-11 years old with pulmonary arterial hypertension results from the European Postmarketing Surveillance program. Pediatr Res 2008 64(2) 200-4. 

Mounger EJ (1973) Hypertension resulting from segmental renal artery infarction. Urology 1 189-190... 

This is an inherited condition in which there is a deficiency of one of the enzymes of cortisol biosynthesis. The resulting low plasma cortisol levels result in high levels of ACTH production because of the absence of feedback control. This in turn results in the accumulation of androgens and cortisol precursors. The consequences of this are pseudohermaphroditism in the female child and virilization in the male child. Deficiencies of 3 -dehydrogenase, 21 -hydroxylase and 1 IjS-hydroxylase have been described. The most common is 21 -hydroxylase deficiency, in which there is abnormal sodium loss (the salt-losing syndrome), due to impaired aldosterone production. 11 -Hydroxylase deficiency results in the excess secretion of 11-deoxycorticosterone and since this is an active mineralocor-ticoid, salt and water retention and hypertension result. 

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