Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A course of hemosorption combined with chemotherapy resulted in much less frequent attacks of angina pectoris and in compensation of cardiac insufficiency in 27 coronary heart disease patients resistant to chemotherapy. There was an increase in the drugs efficacy. Sensitivity of the lymphocytes to chemotherapeutic agents administered rose as shown by rosette test due to specific unlocking of the receptors. The underlying mechanism of hemosorption-related compensation of cardiac insufficiency implies correction of secondary hyperaldosteronism and a decrease in the level of ADH leading to enhanced diuresis, natriuresis, inhibited kaliuresis and to normal values of blood electrolytes.
 ...
PMID:[Hemosorption in the treatment of patients with ischemic heart disease and drug-resistant stenocardia]. 281 Dec 47

New method for measuring plasma and urinary Na-K-ATPase inhibitor (ATPI) was developed. Plasma and urine were extracted with reversed phase cartridge column and sample was reconstituted by assay buffer. Na-K-ATPase inhibitory activity of sample was monitored by continuously recording the absorbance of NADH at 340 nm, which coupled to the dephosphorylation of ATP. Ouabain was used for standards of Na-K-ATPase inhibition and this standard showed good linearity ranged 5-100 nmol/ml. Using this new method, P-ATPI and U-ATPI were quantitatively evaluated and paradoxical Na-K-ATPase stimulating phenomenon which observed in conventional method (Hamlyn et al) was diminished. Adopting of this new method for measuring plasma(P-) and urinary(U-)ATPI, and radioimmunoassay for P- and U-digitalis-like substance(DLS)--using crossreactivity to anti digoxin antibody--, these substances were estimated in patients with essential hypertension (EHT), chronic heart failure(CHF), primary and idiopathic hyperaldosteronism(HA), hyperthyroidism(BA) and chronic renal failure(CRF). In EHT, U-DLS, P-DLS, U-ATPI, P-ATPI were significantly higher than those of control(C). In CHF and BA, U-DLS and -ATPI were also significantly higher than those of C. In HA, U-ATPI, DLS distributed in wide range, and a few patients showed high levels of U-DLS and -ATPI. In CRF, P-DLS and -ATPI levels were significantly higher than those of C in prehemodialytic state but P-ATPI was significantly decreased after hemodialysis. From these results it is suggested that 1) DLS and ATPI might contribute to the etiology of hypertension. 2) Volume expansion stimulates the secretion of DLS and ATPI. 3) Stimulatory effect of volume expansion and inhibitory effect of mineralocorticoid may be responsible for wide distribution of these factors in HA. 4) DLS and ATPI are not the same substances.
 ...
PMID:[Endogenous digitalis-like substance and Na-K-ATPase inhibitor in cardiovascular and renal disease]. 283 14

Overactivity of the renin-angiotensin-aldosterone system occurs in the syndrome of congestive cardiac failure. Aldosterone overactivity is crucially involved in maintaining the oedematous state as evidenced by its often complete correction by adrenalectomy, or by aldosterone antagonists, in both experimental and clinical heart failure. The hyperaldosteronism of heart failure can also be attacked by angiotensin-converting enzyme (ACE) inhibition, which not only blocks the angiotensin drive to aldosterone, but also unloads the heart by blocking renin-angiotensin-mediated vasoconstriction. Accordingly, ACE inhibition alone, if continued in full dosage, can often reduce or obviate the need for daily thiazide diuretic therapy. This specific, two-pronged therapy with fewer side effects emerges as a primary strategy for the treatment of congestive heart failure. To learn more about why and how the renin system becomes involved in heart failure, the renal functional abnormalities have been re-examined. The effects of sodium administration on central haemodynamics and on the activity of the renin system have als been studied. This research has led to a consideration of the role of atrial natriuretic hormone in this pathophysiological interplay. The study recharacterized renal haemodynamic patterns and indicated that in congestive heart failure there is a disproportionate diversion of blood away from the kidneys because of afferent vasoconstriction. However, the glomerular filtration rate is maintained by concurrent efferent arteriolar constriction, expressed by a rising filtration fraction. As heart failure advances, the filtration fraction can no longer rise. At this point, the glomerular filtration rate becomes flow-dependent and falls commensurately with the declining cardiac output. These intrarenal patterns may be mediated in part by increased intrarenal renin activity resulting from heart failure and diuretic therapy. A further study of the abnormal renin system activity operating in heart failure has shown it to be very sensitive to dietary salt intake. Thus, consuming modest amounts of salt (100 mEq/day) was sufficient to markedly suppress renin and aldosterone values. However, since peripheral resistance was not changed, another non-renin, sodium-related mechanism must take over to sustain increased arterial constriction. The fact that captopril challenge evoked no response before and a large response after sodium depletion supports this concept. preliminary data suggest that atrial natriuretic hormone may also be important in congestive heart failure by opposing renin system activity at 4 sites.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Endocrine mechanisms in congestive cardiac failure. Renin, aldosterone and atrial natriuretic hormone. 295 86

Research on the physiological role of atrial peptides in man is limited, and the potential for these peptides, or more stable analogues, in therapeutics is uncertain. It is clear, however, that plasma levels of immunoreactive atrial natriuretic peptide (IR-ANP) are increased in volunteers taking a high sodium diet, and are elevated in patients with heart failure, chronic renal failure, and primary aldosteronism. There is suggestive evidence that IR-ANP levels are increased also in essential hypertension, although overlap with normotensives is considerable. Injection or infusion of atrial peptides into man results in a diuresis, an increased output of urine electrolytes, a fall in blood pressure and a rise in heart rate, suppression of aldosterone and sometimes of renin also, and stimulation of norepinephrine. In essential hypertensives, urinary effects may be greater than in normotensives. Heart failure patients show a rise in cardiac output and falls in both systemic and pulmonary arterial pressure. Over the next few years and especially if specific antagonists can be developed, the physiologic and pathophysiologic roles of atrial peptides in normal man and in clinical disorders should be clarified. It is possible that stable analogues of atrial peptides will find a place in the treatment of cardiac failure, renal failure, and perhaps hypertension.
 ...
PMID:Atrial natriuretic peptides in man. 296 23

Angiotensin converting enzyme (ACE) inhibitors are not known to have a direct effect on the myocardium. However, there is some evidence to suggest that they can play an important role in protecting the heart during the evolution of hypertensive and coronary arterial disease, both acutely and on a long term basis. Reduction of afterload by balanced arterial and venular dilatation has led to a sustained improvement of cardiac performance both in hypertension and heart failure. Reversal of cardiac hypertrophy has been shown to restore inotropic responsiveness to stimulators of the adenylate cyclase system. Following myocardial infarction, captopril has prevented undue ventricular dilatation and normalized left ventricular chamber stiffness; this prevented deterioration of cardiac function and improved long term survival after infarction. Control of secondary aldosteronism and prevention of hypokalaemia can play an important role in the prevention of cardiac arrhythmias. The lack of reflex sympathetic stimulation during long term captopril therapy can also play a favourable role in that respect. Although highly speculative, evidence is accumulating that ACE inhibition could have a cardioprotective effect in acute myocardial ischaemia. It is based on the demonstration that renin can be produced by myocardial cells, that angiotensin is liberated by the ischemic myocardium and that angiotensin in high renin conditions plays an active constrictor role in regulating the coronary circulation.
 ...
PMID:Prospectives for angiotensin converting enzyme inhibition in heart diseases. 300 6

The emergence of diuretic drugs and angiotensin converting enzyme (ACE) inhibitors ranks amongst the major therapeutic advances of modern medicine. The discovery of these drug groups arose largely by chance, yet each has dramatically influenced the treatment of congestive cardiac failure and arterial hypertension. The central role which diuretics have had in the management of both oedema and hypertension hinges on their ability to induce a net renal excretion of solute and water by selective interference with either active or passive ion transport processes in different segments of the nephron. Irrespective of sites of action, the continued antihypertensive action of diuretics is characterized by a reduction in plasma volume and extracellular fluid (ECF) volume that lasts for as long as the diuretic is given. The mechanism of this effect remains unclear but may involve autoregulatory reactions that leave cardiac output unaltered but maintain a sustained reduction in total peripheral resistance. ACE inhibitors also lower blood pressure by decreasing total peripheral resistance, leaving cardiac output, plasma volume and ECF volume unchanged. The detailed way these haemodynamic changes are achieved remains unknown but inhibition of converting enzyme present not only in the kidney but also in many extrarenal tissue sites, appears important. In both hypertension and cardiac failure, however, the kidney acts as a key target organ for ACE inhibitors. The increased renal vascular resistance and inappropriate renal salt excretion are reversed with enhanced renal blood flow and saluresis. Both angiotensin II (AII) and vasopressin-mediated contraction of glomerular mesangial cells is inhibited, making glomerular filtration more efficient. Reduced aldosterone secondary to blockade of AII formation contributes to saluresis whilst encouraging positive potassium balance. ACE inhibition also impairs breakdown of kinins which may contribute to intrarenal and peripheral vasodilation either on their own or via release of prostaglandins and other vasoactive substances. The hypotensive actions of diuretics are potentiated by ACE inhibition primarily through blockade of AII formation and prevention of secondary aldosteronism. In combination, these drugs permit low doses to be used because of their synergistic effects. Caution has to be exercised whenever ACE inhibition is used, without and especially with diuretics, in the management of renovascular hypertension and other low-perfusion states. In these circumstances, AII plays an important autoregulatory role in preserving glomerular filtration through an increase in post-glomerular resistance.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Evolution of diuretics and ACE inhibitors, their renal and antihypertensive actions--parallels and contrasts. 303 17

The major antihypertensive mechanism of calcium antagonists is by decreasing the systemic vascular resistance, modified by the counter-regulatory responses of the baroreflexes and the renin-angiotensin-aldosterone system. In severe hypertension, the concept that calcium overload of the vascular myocyte could precipitate or aggravate peripheral vasoconstriction provides a logical basis for the use of these agents as first choice therapy; nifedipine, especially, has been well tested. As monotherapy for mild to moderate hypertension each of the three first-generation agents compares well with beta-blockers. Calcium antagonists may have a special role in the therapy of certain patient groups (elderly, black) or in those subjects whose life style involves intense physical or mental exertion (hemodynamics better maintained than with beta-blockade) or in patients with early end-organ damage such as left ventricular hypertrophy or renal insufficiency. However, the goal blood pressure may not be reached during monotherapy so that drug combinations may be required. Further indications for these compounds are as follows. Verapamil and diltiazem are frequently used in supraventricular tachycardias including acute and chronic atrial fibrillation. In the arrhythmias of the Wolff-Parkinson-White syndrome, there is the potential danger of provocation of anterograde conduction. Further indications for calcium antagonists, still under evaluation, include congestive heart failure (controversial), hypertrophic cardiomyopathy (verapamil), primary pulmonary hypertension (high doses required), Raynaud's phenomenon (nifedipine and diltiazem effective), peripheral vascular disease (proof not yet documented), cerebral insufficiency and subarachnoid hemorrhage (nimodipine promising), migraine, exertional bronchospasm, renal disease, atherosclerosis (experimental), and primary aldosteronism (nifedipine inhibits aldosterone release). Second-generation agents include dihydropyridines, such as nitrendipine, nicardipine, felodipine, amlodipine, nisoldipine, nimodipine, and isradipine. From these will be selected agents that are longer acting and provide higher vascular selectivity. New preparations of existing agents include slow-release formulations of nifedipine, verapamil, and diltiazem. Minor side effects include those caused by vasodilation (flushing and headaches), constipation (verapamil), and ankle edema. Serious side effects are rare and result from improper use of these agents, as when intravenous verapamil is given to patients with sinus or atrioventricular nodal depression from drugs or disease, or nifedipine to patients with aortic stenosis. The potential of a marked negative inotropic effect is usually offset by afterload reduction, especially in the case of nifedipine. Yet caution is required when calcium antagonists, especially verapamil, are given to patients with myocardial failure unless caused by hypertensive heart disease. Drug interactions of calcium antagonists occur with other cardiovascular agents such as alpha-adrenergic blockers, beta-adrenergic blockers, digoxin, quinidine, and disopyramide.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Calcium channel antagonists. Part III: Use and comparative efficacy in hypertension and supraventricular arrhythmias. Minor indications. 315 29

Elderly patients have a higher incidence of symptomatic cardiac arrhythmias and greater management problems than younger patients. This is due to the frequency of occult and overt cardiovascular disease, reduction in cardiac reserve as a consequence of the aging process, and coexistence of other disorders which provide a substrate for iatrogenic disease. The last problem is largely due to electrolyte disturbances induced by diuretic therapy for hypertension and heart failure. The major electrolyte disturbance implicated in arrhythmogenesis is diuretic-induced hypokalemia. There is no doubt that arrhythmias are caused by severe hypokalemia (less than 2.5 mEq/l), or by a milder degree of hypokalemia in digitalis-treated patients or those with left ventricular hypertrophy, but the literature contains conflicting data regarding the importance of milder hypokalemia. The most compelling study in support of its importance used a crossover study design in hypertensive patients with coronary disease and showed that mild degrees of hypokalemia induced by thiazide diuretics increased the tendency to arrhythmia when compared with normokalemia on a potassium-sparing diuretic. Diuretic-induced magnesium deficiency is also regarded by some to be as important as hypokalemia, but the evidence is less extensive. Thus, it appears reasonable to avoid hypokalemia and hypomagnesemia. The optimum therapeutic approach in using diuretics is to keep the dose as low as possible, restrict dietary sodium, and add potassium supplements. Since, in many cases of hypertension, hypokalemia is due to secondary hyperaldosteronism, the use of angiotensin-converting enzyme inhibitors is another therapeutic approach that is effective in hypertension and heart failure.
 ...
PMID:Arrhythmias, electrolytes, and ACE inhibitor therapy in the elderly. 344 May 24

Beta agonist therapy for heart failure has been disappointing, perhaps because of renin induced aldosteronism. To investigate this possibility we measured plasma renin activity (PRA) in 23 patients (17 male, 6 female, age 41-70) with New York Heart Association stage III heart failure due to ischaemic heart disease in a placebo controlled trial over one month. All patients received constant doses of digoxin and diuretics throughout the trial. Compliance was confirmed in all patients by digoxin and prenalterol assay. In a preliminary (dose titration) study of 9 patients there was a progressive, but non-significant rise of mean PRA from 14.8 to 17.6 and 27.7 ng/ml per h with doses of 20, 50 and 100 mg of prenalterol, respectively. After one month of treatment with prenalterol (n = 11), PRA was 12.8 +/- 2.4 (SEM) ng/ml per h which was not significantly different from the initial level of 14.4 +/- 2.3 ng/ml per h (n.s.). The placebo group (n = 12) results were 13.8 +/- 4.2 ng/ml per h at entry and 14.4 +/- 5.2 ng/ml per h at one month (n.s.). These results indicate that PRA is elevated by acute treatment with the partial beta agonist prenalterol but stimulation of renin secretion does not appear to occur with chronic therapy.
 ...
PMID:Effect of the partial beta-agonist prenalterol on plasma renin activity in patients with left ventricular failure. 354 8

Operation for tumors responsible for a Conn's syndrome was performed in 16 patients, 11 women and 5 men, over a period of 13 years, the average time before diagnosis being 5 1/2 years. All patients presented hypertension, permanent in 14 and paroxysmal in 2 cases while blood potassium levels were below 3 mmol/l in all patients. Diagnosis was confirmed by elevation of plasma aldosterone and of urine tetrahydroaldosterone, associated with low plasma renin activity not responding to a stimulus. The tumor was demonstrated by imaging in 15 cases before operation and its mean size was 1.7 cm. Investigatory methods for diagnosis and localization are discussed. One patient died during the immediate post-operative period from decompensated cardiac failure. Long-term review showed persistent hypertension in 5 patients but electrolyte disturbances were corrected in all cases. Lack of consistency of results of surgical reduction in case of hyperplasia suggests that only patients with hyperaldosteronism related to an adrenal cortex tumor should be operated upon.
 ...
PMID:[Surgery of Conn's syndrome. Apropos of 16 cases]. 370 May


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>