Diuretics are used extensively in hospitals and in community medical practice for the management of cardiovascular diseases. They are used frequently as the first line treatment for mild to moderate hypertension and are an integral part of the management of symptomatic heart failure.
What is the role of diuretics in heart failure?
Diuretic efficacy may be limited by adverse neurohormonal activation and by ‘congestion-like’ symptoms. Diuretics are an extremely useful and varied class of agent for the management of hypervolaemic states. This review summarises the basic features of diuretics, including their mechanism of action, indications and adverse effects in heart failure.
Do diuretics reduce the antihypertensive effect of other classes of medications?
The antihypertensive effect of diuretics may be lessened if the sodium intake is more than 8 g/day; hence, dietary sodium should be restricted. Diuretics enhance the effectiveness of other classes of antihypertensive agents when used in combination.
What are diuretics used for?
Diuretics are used extensively in hospitals and in community medical practice for the management of cardiovascular diseases. They are used frequently as the first line treatment for mild to moderate hypertension and are an integral part of the management of symptomatic heart failure.
What is the main function of diuretics drug?
Diuretics, sometimes called water pills, help rid your body of salt (sodium) and water. Most of these medicines help your kidneys release more sodium into your urine. The sodium helps remove water from your blood, decreasing the amount of fluid flowing through your veins and arteries. This reduces blood pressure.
How do diuretics help cardiac output?
Abstract. The main operational objective of diuretic therapy in patients who present congestive heart failure and hypertension is to reduce or to suppress excess bodily fluid. Effective diuretic therapy decreases cardiac size when the heart is dilated, and it reduces lung congestion and excess water.
How does diuretics reduce the risk of CVD?
All diuretics initially lower the blood pressure by increasing urinary sodium excretion and reducing plasma volume, extracellular fluid volume, and cardiac output.
What effect does a diuretic have on the heart?
They help the kidneys eliminate sodium and water from the body. This process decreases blood volume, so the heart has less to pump with each beat, which in turn lowers blood pressure.
What causes the need for diuretics?
Diuretics. Diuretics, also called water pills, are medications that help the body expel excess fluid. They are commonly prescribed for conditions like heart failure, chronic kidney disease, and high blood pressure.
How do loop diuretics treat heart failure?
Loop Diuretics: Loop diuretics remain the mainstay therapy for fluid removal in patients with HF. They exert their action by inhibiting the sodium-potassium-chloride cotransport system located within the thick ascending limb of the loop of Henle.
What is the mechanism of action for diuretics?
They act by diminishing sodium reabsorption at different sites in the nephron, thereby increasing urinary sodium and water losses. A second class of diuretics, sometimes termed aquaretics, instead inhibit water reabsorption by blocking vasopressin receptors along the connecting tubule and collecting duct.
What diuretics are used for heart failure?
[4] The most commonly used diuretics in HF are loop diuretics, thiazides and potassium-sparing diuretics.
How do diuretics cause vasodilation?
The direct vasodilator actions of thiazide diuretics on isolated vessels are associated with an increase in Rb+ efflux (as a marker for K+ efflux)1032 and hyperpolarization of the plasma membrane and are inhibited by selective blockers of the KCa channel.
What does diuretic effect mean?
A type of drug that causes the kidneys to make more urine. Diuretics help the body get rid of extra fluid and salt. They are used to treat high blood pressure, edema (extra fluid in the tissues), and other conditions.
Why is furosemide used to treat cardiovascular disorders?
Furosemide is given to help treat fluid retention (edema) and swelling that is caused by congestive heart failure, liver disease, kidney disease, or other medical conditions. It works by acting on the kidneys to increase the flow of urine.
Do diuretics improve survival in heart failure?
A meta-analysis of three small randomized clinical trials11–13 (n = 236, events = 15, follow up = 4−52 weeks) showed that diuretic use was associated with reduced mortality in HF. An observational study, in contrast, demonstrated that diuretics increased mortality and hospitalization in systolic HF.
Do diuretics decrease preload or afterload?
Diuretics induce sodium and water excretion, leading to decreased cardiac preload and wall tension, and an effective decrease of symptomatic pulmonary and systemic congestion.
How does furosemide increase cardiac output?
Furosemide (Lasix) It increases the excretion of water by interfering with the chloride-binding cotransport system, inhibiting sodium and chloride reabsorption in the ascending loop of Henle and distal renal tubule.
Do diuretics reduce afterload?
When used in long- term therapy, diuretics also reduce the afterload of the heart. This effect is the result of a reduced pressor responsiveness (sensitivity) of the arterial system.
How do diuretics decrease peripheral resistance?
Thiazide diuretic (TZD)-mediated chronic reduction of arterial pressure is thought to occur through decreased total peripheral vascular resistance. Further, the decreased peripheral vascular resistance is accomplished through TZD activation of an extrarenal target, resulting in inhibition of vascular constriction.
What are some examples of diuretics?
Examples of diuretics. There are three types of diuretics: Thiazide. Loop. Potassium sparing. Each type affects a different part of your kidneys. Some pills combine more than one type of diuretic or combine a diuretic with another blood pressure medication.
What is the name of the pill that helps you get rid of salt?
Find out how they work and when you might need them. By Mayo Clinic Staff. Diuretics , sometimes called water pills, help rid your body of salt (sodium) and water. Most of them help your kidneys release more sodium into your urine.
Can thiazide be used for high blood pressure?
When diuretics are used. Thiazide diuretics are recommended as one of the first drug treatments for high blood pressure. If diuretics aren't enough to lower your blood pressure, your doctor might add other blood pressure medications to your treatment plan.
Can thiazide cause low potassium levels?
If you take a thiazide diuretic, your potassium level can drop too low (hypokalemia), which can cause life-threatening problems with your heartbeat. If you're on a potassium-sparing diuretic, you can have too much potassium in your blood. Other possible side effects of diuretics include: Dizziness. Headaches.
How do diuretics lower blood pressure?
6 All diuretics initially lower the blood pressure by increasing urinary sodium excretion and reducing plasma volume, extracellular fluid volume, and cardiac output. Within six to eight weeks, the plasma volume, extracellular fluid volume, and cardiac output return towards normal. Beyond this point, the lower blood pressure is related to a decline in peripheral resistance, thereby improving the underlying haemodynamic defect of hypertension. 7 The vasodilatory effect of diuretics is probably related to the loss of sodium and water from the vessel wall. 8 In addition, some of the vasodilatory action is mediated through the release of prostacyclin and endothelial derived relaxing factor. 9 The mechanism responsible for the lowered peripheral resistance may also involve activation of the potassium channel. 10
Which diuretic is the most cost effective for mild to moderate hypertension?
Low dose thiazide diuretics are the most cost effective agents in mild to moderate hypertension.
What is the best treatment for hypertension?
There are several general measures and pharmacological agents that are known to treat hypertension adequately. Diuretics, in particular low dose thiazide and thiazide-like diuretics, are widely used in the treatment of hypertension. They have excellent outcome data and high safety and low side effects profiles. In this article, the physiology, pharmacological actions, side effects, and outcome data of the use of diuretics in hypertension are reviewed. In addition, the effective use of diuretics in the management of hypertension is discussed.
What is the role of sodium in the tubular cell?
In the distal convoluted tubule and in the cortical collecting duct, sodium is transported at the apical level of the tubular cell through a sodium channel. Sodium is then exchanged for potassium at the basal membrane as a result of the activity of Na + –K + ATPase. The activity of this enzyme is enhanced by aldosterone, the mineralocorticoid hormone secreted by the adrenal zona glomerulosa. Loop diuretics, thiazides, and metolazone, as well as triamterene, amiloride, and spironolactone, act in the late portion of the distal convoluted tubule and the cortical collecting duct. Triamterene and amiloride have weak natriuretic action. Spironolactone is a competitive antagonist of aldosterone and, consequently, inhibits pump activity. Amiloride and triamterene block the apical sodium transport. The elimination of potassium is reduced by diuretics acting in the most distal portions of the nephron because of decreased sodium-potassium exchange. In contrast, loop diuretics and diuretics acting in the early distal convoluted tubule increase kaliuresis and tend to cause hypokalaemia. This is mainly because these agents enhance the delivery of sodium downstream and subsequently accentuate the sodium-potassium exchange. As a result, more sodium is available for resorption in the late distal convoluted tubule and the cortical collecting duct.
How effective is diuretic therapy?
18 High dose diuretic therapy was shown to reduce the incidences of stroke (relative risk of 0.49; 95% CI 0.39 to 0.62) and congestive heart failure (relative risk of 0.17; 95% CI 0.07 to 0.41). Low dose diuretic therapy not only prevented stroke (relative risk of 0.66; 95% CI 0.55 to 0.78) and congestive heart failure (relative risk of 0.58; 95% CI 0.44 to 0.76) but also reduced coronary disease (relative risk of 0.72; 95% CI 0.61 to 0.85) and total mortality (relative risk of 0.90; 95% CI 0.81 to 0.99).
Why do diuretics reduce potassium?
The elimination of potassium is reduced by diuretics acting in the most distal portions of the nephron because of decreased sodium-potassium exchange. In contrast, loop diuretics and diuretics acting in the early distal convoluted tubule increase kaliuresis and tend to cause hypokalaemia.
Where do diuretics start?
Diuretics useful in the treatment of hypertension may be divided into four major groups according to their primary site of action within the renal tubule, starting in the proximal portion and moving to the collecting duct. 5 They include agents acting on the proximal tubule, such as carbonic anhydrase inhibitors, which have limited antihypertensive efficacy; loop diuretics; thiazides and related sulphonamide compounds; and potassium sparing agents (table 1).
What is the treatment for symptomatic heart failure?
Diuretics for treatment of symptomatic heart failure
What is CHF in medical terms?
Such therapies include angiotensin‐converting enzyme (ACE) inhibitors (Grag 1995; Flather 2000; Yusuf 1991; Yusuf 1992) and more recently beta‐blockers (CIBIS‐II 1999; CIBIS III 2005; COMET 2003; COPERNICUS 2001; MERIT‐HF 2000; Waagstein 1993) reduce mortality and morbidity in chronic heart failure .
What is the clinical syndrome of chronic heart failure?
Adult participants with chronic heart failure, defined as a clinical syndrome characterised by breathlessness and fatigue that is caused by an inability of the heart to support an adequate circulation , that may limit exercise tolerance and may lead to pulmonary congestion and peripheral oedema.
Is diuretic a first line treatment for congestive heart failure?
Chronic heart failure is a major cause of morbidity and mortality worldwide. Diuretics are regarded as the first‐line treatment for patients with congestive heart failure since they provide symptomatic relief. The effects of diuretics on disease progression and survival remain unclear.
Is spironolactone a diuretic?
We are uncertain whether the main action of spironolactone is as a diuretic. There is debate among the experts as to how these agents actually act. Our approach was to take the classes of diuretics for example thiazides, loop, or potassium‐sparing diuretics and analyse them separately to the other agents e.g. spironolactone, and then to provide an overall assessment. However we found insufficient information within the sub‐groups of each class of diuretic to carry out this approach.
Can ACE inhibitors be used for heart failure?
Attempts to substitute ACE inhibitors for diuretics can lead to pulmonary and peripheral congestion (Richardson 1987). Diuretics should not be used alone in the treatment of chronic heart failure (ACC/AHA 2009). Even when diuretics are successful in controlling symptoms and fluid retention, diuretics alone are unable to maintain the clinical stability of patients with chronic heart failure for long periods of time (Richardson 1987). The risk of clinical decompensation can be reduced, however, when diuretics are combined with digoxin, ACE inhibitors, and beta‐blockers (Captopril 1988).
Do diuretics help with heart failure?
The available data from several small trials show that in patients with chronic heart failure, conventional diuretics appear to reduce the risk of death and worsening heart failure compared to placebo. Compared to active control, diuretics appear to improve exercise capacity.
Why are diuretics used in heart failure?
The use of diuretics is common in patients with heart failure (HF), to relieve the congestive symptoms of HF. Although they are widely used, there are limited data on their ability to modulate HF-related morbidity and mortality. Diuretic efficacy may be limited by adverse neurohormonal activation and by ‘congestion-like’ symptoms. Diuretics are an extremely useful and varied class of agent for the management of hypervolaemic states. This review summarises the basic features of diuretics, including their mechanism of action, indications and adverse effects in heart failure.
Why do we need diuretics?
Diuretics are used to achieve and maintain euvolaemia (the patient’s ‘dry weight’) with the lowest possible dose. This means that the dose must be adjusted, particularly after restoration of the dry body weight, to avoid the risk of dehydration, which leads to hypotension and renal dysfunction.[10] .
What is diuretic resistance?
Diuretic resistance is a common problem in HF patients. Removal of excessive fluid is usually achieved by a combination of salt restriction and loop diuretics, but in some cases congestion persists despite adequate diuretic therapy. This has been termed diuretic resistance. The prevalence of diuretic resistance in the HF population is unknown due to the heterogeneity of the populations studied, the frequent comorbidity, the different treatment regimens, as well as to the different definitions used in various clinical trials. In a retrospective analysis of 1,153 patients with advanced HF, 402 patients had diuretic resistance (defined in this study as requirement of furosemide >80 mg or bumetanide >2 mg daily).[20] Diuretic resistance was independently associated with total mortality, sudden death and pump failure death. Loop diuretics are ‘threshold drugs’. HF shifts the dose-response curve for loop diuretics downward and to the right. Thus a higher starting dose of loop diuretics is needed in order to achieve the same level of sodium excretion.[21]
Why are sodium ducts less effective in glomerular filtration?
They are less effective in patients with reduced glomerular filtration, because they exert their diuretic effects from the luminal side of the nephron.
What is the effect of loop diuretics on sodium?
This causes decreased sodium and chloride reabsorption and increased diuresis.[5]
Is furosemide a diuretic?
Furosemide is by far the most common oral loop diuretic, but patients with resistance to oral furosemide therapy may benefit from trials with second-generation oral loop diuretics (bumetanide and torasemide). These may be more efficacious, due to their increased oral bioavailability and potency. The longer half-life of torasemide may limit the previously described rebound phenomenon.[11] In the prospective TORasemide In Chronic heart failure (TORIC) study, the use of torasemide was associated with lower mortality than furosemide in patients with HF. Furthermore, torasemide has been reported to attenuate LV remodelling in patients with congestive HF (CHF) to a greater extent than furosemide.[12] Torasemide has also been reported to attenuate LV remodelling in patients with HF to a greater extent than furosemide.[13] Although international guidelines do not define which diuretic should be preferred, there is not enough strong evidence to recommend torasemide and bumetanide over furosemide in HF.
Do loop diuretics cause dilation?
Loop diuretics also enhance the synthesis of prostaglandins, which cause renal and venous dilatation. This explains some of the cardiac effects, such as reduction in pulmonary wedge pressure.[6] However, it is important to recognise that the diuretic actions of loop diuretics may be decreased by the concomitant use of non-steroidal anti-inflammatory drugs (NSAIDs), possibly because this inhibits renal prostaglandin synthesis. Loop diuretics include furosemide, bumetanide, torsemide and ethacrynic acid.
How does diuretic affect the kidneys?
Each of the three types of diuretic medication increases the amount of sodium you excrete through urination, but they affect different areas of your kidneys. Your kidneys are the filters through which toxins and excess fluids are flushed from your body.
What is the best diuretic to control blood pressure?
One of the most commonly prescribed thiazide-like diuretics is chlorthalidone. Studies show that it may be the best diuretic to control blood pressure and prevent death. Indapamide is another thiazide-like diuretic.
What are some examples of thiazides?
Examples of thiazides include metolazone (Zaroxolyn), indapamide (Lozol), and hydrochlorothiazide (Microzide).
What foods can help with hypertension?
dark leafy greens, such as kale and spinach. squash. mushrooms. potatoes. yogurt. fish. Potassium-sparing diuretics don’t pose as much as a threat to your potassium levels. However, they aren’t as effective in treating hypertension as the other types of diuretic medications, so they are often prescribed along with other drugs.
How do loop diuretics work?
Loop diuretics remove excess fluid by causing the kidneys to produce more urine.
Can diuretics help with high blood pressure?
High blood pressure can be a contributing factor in the development of various forms of heart disease. When chosen as a treatment for hypertension, diuretics have proven to be effective in preventing heart attack and stroke in many individuals.
Is it safe to take diuretics?
Risks and Side Effects. Diuretics are generally safe for most people when taken as prescribed. The most common side effect of diuretics is increased urination. Your potassium, glucose, and cholesterol levels may fluctuate depending on the type of diuretic you’re taking.
What are the risks and side effects of diuretic use in heart failure?
Diuretic use for heart failure carries some risks because the loss of minerals can cause electrolyte imbalance and lead to conditions such as:
What are diuretics?
Diuretics, also known as water pills, are medications that promote urination and reduce fluid retention in the body. Diuretics inhibit the kidney from reabsorbing sodium, which normally happens during blood filtration. The release of sodium also leads to the elimination of excess fluid by way of increased urine output.
What is congestive heart failure?
Heart failure can cause edema when extra fluid seeps into the lung cavity or other cavities. Diuretics treat this symptom, but do not cure heart failure.
Why are diuretics used in heart failure?
Diuretics are an integral part of heart failure treatment, along with other medications to treat the underlying cause of heart failure. Diuretics help the kidneys flush out the excess fluid and maintain normal blood volume.
How do diuretics work?
Diuretics inhibit the nephron’s proteins, inducing the kidneys to flush minerals along with excess water.
What is the name of the enzyme that balances the pH of the blood?
A carbonic anhydrase is an enzyme that balances the blood pH levels. Carbonic anhydrase inhibitors block the enzyme, promoting the excretion of sodium, potassium, bicarbonate and water. The carbonic anhydrase inhibitor used for heart failure is: Acetazolamide ( Diamox)
What are non-diuretic alternatives?
Non-diuretic alternatives. Vasopressin antagonists: Vasopressin antagonists are a new class of drugs being studied for use in heart failure. This class of drugs works by blocking vasopressin, which is an antidiuretic hormone produced by the pituitary gland. Ultrafiltration: Ultrafiltration is the removal of excess fluid in the blood with the use ...
Methods
The ALLHAT rationale and design have been reported previously. 13,14 Participants were men and women aged ≥55 years who had stage 1 or 2 hypertension plus an additional risk factor for CHD. Individuals with a history of hospitalized or treated symptomatic HF or known left ventricular ejection fraction <35% were excluded.
Results
Detailed baseline characteristics of ALLHAT participants have been reported previously. 13 Briefly, mean age was 67 years, 53% were male, 25% had a history of CHD, and 36% had a history of diabetes mellitus.
Discussion
ALLHAT provided a unique opportunity to examine the relative benefit of several antihypertensive regimens in preventing HF occurrence in a diverse population of high-risk patients with hypertension.
Footnotes
Correspondence to Barry R. Davis, MD, PhD, The University of Texas School of Public Health, 1200 Herman Pressler St, E-809, Houston, TX 77030. E-mail [email protected]
