Heart failure diuretics

Artificial Hearts. Congestive heart failure (CHF) is a common cause of disabiHty and death. It is estimated that three to four million Americans suffer from this condition. Medical therapy in the form of inotropic agents, diuretics (qv), and vasofilators is commonly used to treat this disorder (see Cardiovascularagents). Cardiac transplantation has become the treatment of choice for medically intractable CHF. Although the results of heart transplantation are impressive, the number of patients who might benefit far exceeds the number of potential donors. Long-term circulatory support systems may become an alternative to transplantation (5). 

ACE inhibitors can be administered with diuretics (qv), cardiac glycosides, -adrenoceptor blockers, and calcium channel blockers. Clinical trials indicate they are generally free from serious side effects. The effectiveness of enalapril, another ACE inhibitor, in preventing patient mortaUty in severe (Class IV) heart failure was investigated. In combination with conventional dmgs such as vasodilators and diuretics, a 40% reduction in mortaUty was observed after six months of treatment using 2.5—40 mg/d of enalapril (141). However, patients complain of cough, and occasionally rash and taste disturbances can occur. 

Diuretics are one of the dmg categories most frequendy prescribed. The principal uses of diuretics are for the treatment of hypertension, congestive heart failure, and mobilization of edema fluid in renal failure, fiver cirrhosis, and ascites. Other applications include the treatment of glaucoma and hypercalcemia, as well as the alkafinization of urine to prevent cystine and uric acid kidney stones. 

Loop diuretics are the drugs of choice for the treatment of edematous patients with congestive heart failure, cirrhosis of the liver, and nephrotic syndrome. Excretion of Na is helpful only to the extent that some of the... 

The use of V2 antagonists is promising in the treatment of the hyponatremia that usually accompanies congestive heart failure and cirrhosis, two edematous conditions in which the use of diuretics is indicated. In addition, V2 antagonists may be beneficial in the treatment of polycystic kidney disease. 

Taylor SH (2000) Diuretic therapy in congestive heart failure. Cardiol Rev 8 104-114... 

ACE inhibitors do not completely block aldosterone synthesis. Since this steroid hormone is a potent inducer of fibrosis in the heart, specific antagonists, such as spironolactone and eplerenone, have recently been very successfully used in clinical trials in addition to ACE inhibitors to treat congestive heart failure [5]. Formerly, these drugs have only been applied as potassium-saving diuretics in oedematous diseases, hypertension, and hypokalemia as well as in primary hyperaldosteronism. Possible side effects of aldosterone antagonists include hyperkalemia and, in case of spironolactone, which is less specific for the mineralocorticoid receptor than eplerenone, also antiandrogenic and progestational actions. 

Labetalol is used in the treatment of hypertension, either alone or in combination with another drag such as a diuretic. Carvedilol is used to treat essential hypertension and in congestive heart failure to reduce progression of the disease. 

A diuretic is a drug that increases die secretion of urine (ie, water, electrolytes, and waste products) by die kidneys. Many conditions or diseases, such as heart failure, endocrine disturbances, and kidney and liver diseases can cause retention of excess fluid (edema). When die patient shows signs of excess fluid retention, die primary healdi care provider may order a diuretic. There are various types of diuretic drugs, and the primary healdi care provider selects the one that best suits die patient s needs and effectively reduces the amount of excess fluid in body tissues. 

When a diuretic is being administered for heart failure, which of die following would be most indicative of an effective response of diuretic tiierapy ... 

Patients with asymptomatic left ventricular systolic dysfunction and hypertension should be treated with P-blockers and ACE inhibitors. Those with heart failure secondary to left ventricular dysfunction and hypertension should be treated with drugs proven to also reduce the morbidity and mortality of heart failure, including P-blockers, ACE inhibitors, ARBs, aldosterone antagonists, and diuretics for symptom control as well as antihypertensive effect. In African-Americans with heart failure and left ventricular systolic dysfunction, combination therapy with nitrates and hydralazine not only affords a morbidity and mortality benefit, but may also be useful as antihypertensive therapy if needed.66 The dihydropyridine calcium channel blockers amlodipine or felodipine may also be used in patients with heart failure and left ventricular systolic dysfunction for uncontrolled blood pressure, although they have no effect on heart failure morbidity and mortality in these patients.49 For patients with heart failure and preserved ejection fraction, antihypertensive therapies that should be considered include P-blockers, ACE inhibitors, ARBs, calcium channel blockers (including nondihydropyridine agents), diuretics, and others as needed to control blood pressure.2,49... 

Treatment of acute heart failure targets relief of congestion and optimization of cardiac output utilizing oral or intravenous diuretics, intravenous vasodilators, and when appropriate, inotropes. 

TABLE 3-6. Loop Diuretics Used in Heart Failure... 

TABLE 3-9. Intravenous Diuretics Used to Treat Heart Failure-Related Fluid Retention... 

Medications can increase the risk of hyperkalemia in patients with CKD, including angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers, used for the treatment of proteinuria and hypertension. Potassium-sparing diuretics, used for the treatment of edema and chronic heart failure, can also exacerbate the development of hyperkalemia, and should be used with caution in patients with stage 3 CKD or higher. 

Explain the mechanism of action of diuretics in congestive heart failure and hypertension... 

It is this reduction in preload that, in some cases, is beneficial to patients experiencing heart failure or hypertension. Unlike a healthy heart, a failing heart is unable to pump all of the blood returned to it. Instead, the blood dams up and overfills the chambers of the heart. This results in congestion and increased pressures in the heart and venous system and the formation of peripheral edema. Because the failing heart is operating on the flat portion of a depressed cardiac function curve (see Figure 14.2), treatment with diuretics will relieve the congestion and edema, but have little effect on stroke volume and cardiac output. 

Diuretics cause the body to release excess fluids. They are used to help people with congestive heart failure and high blood pressure, as excess fluid makes heart failure and high blood pressure worse. When someone does not have one of... 

Loop diuretics Congestive heart failure and pulmonary edema, ascites... 

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