Management of heart failure
Management of heart failure requires a multimodal approach. It involves a combination of lifestyle modifications, medications, and possibly the use of devices or surgery.
Lifestyle changes
People with congestive heart failure (CHF) are educated to undertake various non-
- Moderate physical activity, when symptoms are mild or moderate; or bed rest when symptoms are severe.
- If BiPAP, dental appliances or surgery. Sleep apnea is an under-recognized risk factor for heart failure.
- Weight reduction – through physical activity and dietary modification, as obesity is a risk factor for heart failure and left ventricular hypertrophy.
- Monitor weight – this is a parameter that can easily be measured at home. Rapid weight increase is generally due to fluid retention. Weight gain of more than 2 pounds is associated with admission to the hospital for heart failure.[2]
- mmoltotal daily intake) is recommended for patients with CHF.
Fluid restriction
According to a
Generally water intake should be limited to 1.5 L daily or less in patients with hyponatremia, though fluid restriction may be beneficial regardless in symptomatic reduction.
Medication
There is a significant evidence–practice gap in the treatment of CHF; particularly the underuse of
Angiotensin-modulating agents
Unless contraindicated or not tolerated, ACE inhibitor (ACE) therapy is recommended for all patients with systolic heart failure, irrespective of symptomatic severity or blood pressure.
A number of studies have been done to investigate whether ACEi plus ARB is better than an ACEi treatment alone in reducing death, disability or hospital admission in CHF with systolic dysfunction. The two largest studies were CHARM-Added and Val-HeFT.[12][13] The conclusion of a Cochrane Database Systematic Review, which included these two studies and five others, was that combining ACEi treatment with ARB was not effective in reducing total mortality RR 0.98 [95% CI 0.9, 1.06] or cardiovascular mortality RR 0.93 [95% CI 0.84, 1.03] when compared with single therapy of an ACEi. Combined therapy did reduce HF-related hospital admissions with an absolute risk reduction of 4.4% but also increased discontinuation of medication due to adverse effects with an absolute risk increase of 3.7%.[14] In plain English, 23 people would need to be treated to reduce one hospitalisation for HF while treating 27 people would harm one person with adverse effects. Thus, combined therapy does not improve mortality and may slightly increase morbidity.
Diuretics
Diuretic therapy is indicated for relief of congestive symptoms. Several classes are used, with combinations reserved for severe heart failure:[1]
- Loop diuretics (e.g. furosemide, bumetanide) – most commonly used class in CHF, usually for moderate CHF
- chlorthalidone, chlorthiazide) – may be useful for mild CHF, but typically used in severe CHF in combination with loop diuretics, resulting in a synergistic effect.
- hypokalaemia.
- Spironolactone is used as add-on therapy to ACEI plus loop diuretic in severe CHF.
- Eplerenone is specifically indicated for post-MI reduction of cardiovascular risk.
If a heart failure patient exhibits a resistance to or poor response to diuretic therapy, ultrafiltration or aquapheresis may be needed to achieve adequate control of fluid retention and congestion. The use of such mechanical methods of fluid removal can produce meaningful clinical benefits in patients with diuretic-resistant heart failure and may restore responsiveness to conventional doses of diuretics.[9]
Newly emerging evidence showed that glucocorticoids could be used in the treatment of decompensated heart failure to potentiate renal responsiveness to diuretics, especially in heart failure patients with refractory diuretic resistance with large dose of loop diuretics.
Beta blockers
Until recently (within the last 20 years), β-blockers were contraindicated in CHF, owing to their negative inotropic effect and ability to produce bradycardia – effects which worsen heart failure. However, current guidelines recommend β-blocker therapy for patients with systolic heart failure due to left ventricular systolic dysfunction after stabilization with diuretic and ACEI therapy, irrespective of symptomatic severity or blood pressure.[9] As with ACEI therapy, the addition of a β-blocker can decrease mortality and improve left ventricular function. Several β-blockers are specifically indicated for CHF including: bisoprolol, carvedilol, nebivolol and extended-release metoprolol. The antagonism of β1 inotropic and chronotropic effects decreases the amount of work the heart must perform. It is also thought that catecholamines and other sympathomimetics have an effect on cardiac remodeling, and blocking their activity can slow the deterioration of cardiac function.
Positive inotropes
Digoxin (a mildly positive inotrope and negative chronotrope), once used as first-line therapy, is now reserved for control of ventricular rhythm in patients with atrial fibrillation; or where adequate control is not achieved with an ACEI, a beta blocker and a loop diuretic.[9] There is no evidence that digoxin reduces mortality in CHF, although some studies suggest a decreased rate in hospital admissions.[23] It is contraindicated in cardiac tamponade and restrictive cardiomyopathy.
The inotropic agent dobutamine is advised only in the short-term use of acutely decompensated heart failure, and has no other uses.[9]
Phosphodiesterase inhibitors such as milrinone are sometimes utilized in severe cardiomyopathy. The mechanism of action is through inhibiting the breakdown and thereby increasing the concentration of cAMP similar to beta adrenoreceptor agonism, resulting in inotropic effects and modest diuretic effects.
Alternative vasodilators
The combination of
Aldosterone receptor antagonists
The RALES trial[26] showed that the addition of spironolactone can improve mortality, particularly in severe cardiomyopathy (ejection fraction less than 25%.) The related medication eplerenone was shown in the EPHESUS trial[27] to have a similar effect, and it is specifically labelled for use in decompensated heart failure complicating acute myocardial infarction. While the antagonism of aldosterone will decrease the effects of sodium and water retention, it is thought that the main mechanism of action is by antagonizing the deleterious effects of aldosterone on cardiac remodeling.
Recombinant neuroendocrine hormones
Nesiritide, a recombinant form of B-natriuretic peptide, is indicated for use in patients with acute decompensated heart failure who have dyspnea at rest. Nesiritide promotes diuresis and natriuresis, thereby ameliorating volume overload. It is thought that, while BNP is elevated in heart failure, the peptide that is produced is actually dysfunctional or non-functional and thereby ineffective.
Vasopressin receptor antagonists
Tolvaptan and conivaptan antagonize the effects of antidiuretic hormone (vasopressin), thereby promoting the specific excretion of free water, directly ameliorating the volume overloaded state, and counteracting the hyponatremia that occurs due to the release of neuroendocrine hormones in an attempt to counteract the effects of heart failure. The EVEREST trial, which utilized tolvaptan, showed that when used in combination with conventional therapy, many symptoms of acute decompensated heart failure were significantly improved compared to conventional therapy alone[28] although they found no difference in mortality and morbidity when compared to conventional therapy.[29]
Devices
CRT: People with NYHA class III or IV, left ventricular ejection fraction (LVEF) of 35% or less and a QRS interval of 120
The COMPANION trial demonstrated that CRT improved survival in individuals with NYHA class III or IV heart failure with a widened QRS complex on an electrocardiogram.[30] The CARE-HF trial showed that patients receiving CRT and optimal medical therapy benefited from a 36% reduction in all-cause mortality and a reduction in cardiovascular-related hospitalization.[31]
However, around one third of patients with LVEF of 35% of less have a QRS complex duration of 120 ms or more. In the remaining two thirds of patients (who have a QRS complex duration of 120 ms or less), CRT may actually be harmful.[32][33]
CCM:
AICD: Patients with NYHA class II, III or IV, and LVEF of 35% (without a QRS requirement) may also benefit from an implantable cardioverter-defibrillator (ICD), a device that is proven to reduce all-cause mortality by 23% compared to placebo in patients who were already optimally managed on drug therapy.[41][42] Patients with severe cardiomyopathy are at high risk for sudden cardiac death due to ventricular dysrhythmias. Although ICDs deliver electrical shocks to resynchronize heart rhythm which are potentially distressing to the patient, they have not been shown to affect quality of life.[43] The number of (appropriate and inappropriate) shocks seems to be associated with a worse outcome.[44] Although they are expensive, ICDs are potentially cost-effective in this setting.[45]
LVAD: Another current treatment involves the use of left ventricular assist devices (LVADs). LVADs are battery-operated mechanical pump-type devices that are surgically implanted in the upper part of the abdomen. They take blood from the left ventricle and pump it through the aorta. LVADs are becoming more common and are often used in patients waiting for heart transplants.
Surgery
The final option, if other measures have failed, is heart transplantation or (temporary or prolonged) implantation of an artificial heart. These remain the recommended surgical treatment options. However, the limited number of hearts available for transplantation in a growing group of candidates, has led to the development of alternative surgical approaches to heart failure. These commonly involve surgical left ventricular remodeling. The aim of the procedures is to reduce the ventricle diameter (targeting Laplace's law and the disease mechanism of heart failure), improve its shape and/or remove non-viable tissue.[46] These procedures can be performed together with coronary artery bypass surgery or mitral valve repair.
If heart failure ensues after a myocardial infarction due to scarring and aneurysm formation, reconstructive surgery may be an option. These aneurysms bulge with every contraction, making it inefficient. Cooley and coworkers reported the first surgical treatment of a left ventricular aneurysm in 1958.[47] They used a linear closure after their excision. In the 1980s, Vincent Dor developed a method using a circular patch stitched to the inside of the ventricle (the endoventricular circular patch plasty or Dor procedure) to close the defect after excision.[48] Dor's approach has been modified by others and is today the preferred method for surgical treatment of incorrectly contracting (dyskinetic) left ventricle tissue, although a linear closure technique combined with septoplasty might be equally effective.[49][50] The multicenter RESTORE trial of 1198 participants demonstrated an increase in ejection fraction from about 30% to 40% with a concomitant shift in NYHA classes, with an early mortality of 5% and a 5-year survival of 70%.[51] It remains unknown if surgery is superior to optimal medical therapy. The STICH trial (Surgical Treatment for IschemiC Heart Failure) will examine the role of medical treatment, coronary artery bypass surgery and left ventricle remodeling surgery in heart failure patients. Results are expected to be published in 2009[needs update] and 2011.[52]
The Batista procedure was invented by Brazilian surgeon Randas Batista in 1994 for use in patients with non-ischemic dilated cardiomyopathy. It involves removal of a portion of viable tissue from the left ventricle to reduce its size (partial left ventriculectomy), with or without repair or replacement of the mitral valve.[53] Although several studies showed benefits from this surgery, studies at the Cleveland Clinic concluded that this procedure was associated with a high early and late failure rate. At 3 years only 26 percent were event-free and survival rate was only 60 percent.[54] Most hospitals have abandoned this operation and it is no longer included in heart failure guidelines.[46]
Newer procedures under examination are based on the observation that the spherical configuration of the dilated heart reduces ejection fraction compared to the elliptical form. Mesh-like constraint devices such as the Acorn CorCap aim to improve contraction efficacy and prevent further remodeling. Clinical trials are underway.[55] Another technique which aims to divide the spherical ventricle into two elliptical halves is used with the Myosplint device.[56]
References
- ^ ISSN 1327-9513
- PMID 17846286.
- ^ PMID 19760574.
- ^ Jackson S, Bereznicki L, Peterson G (2005). "Under-use of ACE-inhibitor and β-blocker therapies in congestive cardiac failure". Australian Pharmacist. 24 (12): 936.
- PMID 2642629.
- PMID 1944425.
- PMID 16160202.
- S2CID 44913094.
- ^ a b c d e National Institute for Clinical Excellence. Chronic heart failure: management of chronic heart failure in adults in primary and secondary care. Clinical Guideline 5. London: National Institute for Clinical Excellence; 2003 Jul. Available from: www.nice.org.uk/pdf/CG5NICEguideline.pdf Archived 27 September 2007 at the Wayback Machine
- S2CID 5650345.)
{{cite journal}}
: CS1 maint: multiple names: authors list (link - S2CID 15011437.)
{{cite journal}}
: CS1 maint: multiple names: authors list (link - S2CID 7383954.)
{{cite journal}}
: CS1 maint: multiple names: authors list (link - PMID 11759645.)
{{cite journal}}
: CS1 maint: multiple names: authors list (link - PMID 22513909.
- S2CID 38687480.
- PMID 13520608.
- PMID 13632954.
- PMID 18971570.
- PMID 17876376.
- S2CID 45800521.
- PMID 21406321.
- S2CID 1892149.
- PMID 10929703.
- PMID 11333991.
- S2CID 12012042.)
{{cite journal}}
: CS1 maint: multiple names: authors list (link - PMID 10471456.
- S2CID 26172590.
- PMID 17384438.)
{{cite journal}}
: CS1 maint: multiple names: authors list (link - PMID 17384437.)
{{cite journal}}
: CS1 maint: multiple names: authors list (link - PMID 15152059.)
{{cite journal}}
: CS1 maint: multiple names: authors list (link - S2CID 13938919.)
{{cite journal}}
: CS1 maint: multiple names: authors list (link - S2CID 205095941.
- PMID 22965336.
- PMID 23229137.
- PMID 24975782.
- PMID 22696514.
- PMID 24265466.
- PMID 25662055.
- ^ Kuschyk, J. (2014). "Der Besondere Stellenwert der Kardialen Kontraktilitätsmodulation in der Devicetherapie". Herzmedizin. Retrieved 6 June 2014.
- ^ clinicaltrials.gov Announcement of a study that will further investigate safety and efficacy of CCM devices
- PMID 15659722.)
{{cite journal}}
: CS1 maint: multiple names: authors list (link - PMID 11907286.
- PMID 18768943.)
{{cite journal}}
: CS1 maint: multiple names: authors list (link - PMID 18768944.)
{{cite journal}}
: CS1 maint: multiple names: authors list (link - PMID 16207849.
- ^ PMID 16087128.
- PMID 13538738.
- S2CID 12777305.
- PMID 15354107.
- PMID 11279407.
- PMID 15464325.
- PMID 18023680.
- ^ "Pioneers of heart surgery". NOVA Online: Cut to the heart. Retrieved 7 November 2007.
- PMID 11326231.
- PMID 14566236.
- PMID 12057702.