Heart failure

Congestive heart failure is defined as "defective cardiac filling and/or impaired contraction and emptying, resulting in the heart's inability to pump a sufficient amount of blood to meet the needs of the body tissues or to be able to do so only with an elevated filling pressure".

History and physical examination
The best findings for detecting increased filling pressure are jugular venous distention and radiographic redistribution. The best findings for detecting systolic dysfunction are abnormal apical impulse, radiographic cardiomegaly, and q waves or left bundle branch block on an electrocardiogram.

The history and physical examination can also be used for patients with advanced heart failure to place the patient into a hemodynamic profile to guide management. Patients in the "cold and wet" category may need to "warm up in order to dry out" by stopping adrenergic beta-receptor blockaders (beta-blockers) and angiotensin-converting enzyme inhibitors (ACE inhibitors).

Chest radiograph
The accuracy of the chest radiograph is below. For diagnosing decreased ejection fraction with: Cardiomegaly Redistribution:
 * sensitivity = 51%
 * specificity = 79%
 * sensitivity = 37%
 * specificity = 85%

For diagnosing increased preload with: Redistribution
 * sensitivity = 65%
 * specificity = 67%

Various definitions have been proposed for determining redistribution; definitions with absolute measurements probably best apply to 72 inch erect, postero-anterior radiograph:
 * Pulonary veins in the upper lobes are larger than the lower lobe vein. Distinguishing pulmonary veins from arteries is not important as pulmonary veins are larger than pulmonary arteries.
 * Upper lobe veins 3 mm or larger in the first anterior interspace
 * Upper lobe veins 7 mm or larger at the level of the pulmonary artery

Echocardiogram
The fractional shortening can estimate the left ventricular ejection fraction.

Goals
There was no improvement by treating for a goal of brain natriuretic peptide less than 400 pg/mL in patients younger than 75 years and less than 800 pg/mL in patients aged 75 years or older.

Medications
The medications for heart failure have been reviewed.

Angiotensin-converting enzyme inhibitors (ACEi)
Angiotensin-converting enzyme inhibitor can reduce morbidity from heart failure.

Angiotensin-converting enzyme inhibitors (ACE inhibitors) should not be used if:
 * Baseline serum potassium is < 5.5 mmol per liter.
 * No prior life-threatening adverse reactions (angioedema or anuric renal failure) during previous exposure to the drug
 * They are not pregnant
 * Systolic blood pressure less than 80 mm Hg
 * Serum levels of creatinine greater than 3 mg per dL
 * Bilateral renal artery stenosis is not present

There is conflicting evidence whether ACE inhibitors are as effective in African-American patients as in Anglo patients.

ACEi combined with angiotensin-receptor blockers
This combination should be avoided due to increased azotemia, hyperkalemia, and symptomatic hypotension.

Beta-blockers
Two cohort studies suggest that the beta-blockers atenolol and carvedilol may be more effect than metoprolol for the treatment of heart failure.

Drugs with intrinsic sympathomimetic activity may have less benefit A systematic review of randomized controlled trials concluded "metoprolol, carvedilol, and bisoprolol all exhibited statistically significant mortality rate reductions compared with placebo, the data were inconclusive for nebivolol or atenolol" and "for every heart rate reduction of 5 beats/min with β-blocker treatment, a commensurate 18% reduction in the risk for death occurred."

There is conflicting evidence whether beta-blockers are as effective in African-American patients as in Anglo patients. This may be due to a polymorphism in African-American patients of the G protein–coupled cell surface receptor kinase (GRK5) (OMIM) that confers a natural "genetic beta-blockade".

Aldosterone antagonists
Aldosterone antagonists, initial dose of spironolactone 12.5 mg or eplerenone 25 mg may be used. Spironolactone can help patients who have New York Heart Association (NYHA) class IV heart failure and had a left ventricular ejection fraction of no more than 35%. , although it is both used incorrectly and at the same time is underutilized. They may be used as long as:
 * Serum creatinine 1.6 mg per dL or less and glomerular filtration rate or creatinine clearance exceeds 30 mL per minute.
 * Baseline serum potassium is < 5.0 mEq per liter

Risk of hyperkalemia is increased if the following drugs are used:
 * Higher doses of ACE inhibitors (captopril greater than or equal to 75 mg daily; enalapril or lisinopril greater than or equal to 10 mg daily).
 * Nonsteroidal anti-inflammatory drugs and cyclo-oxygenase-2 inhibitors
 * Potassium supplements

After starting aldosterone antagonists:
 * Potassium levels and renal function should be checked in 3 days
 * Potassium levels and renal function should be checked at 1 week
 * Potassium levels and renal function should be checked monthly for the first 3 months.
 * Diarrhea or other causes of dehydration should be addressed emergently

Isosorbide dinitrate and hydralazine combination treatment
According to clinical practice guidelines:."
 * "The addition of a combination of hydralazine and a nitrate is reasonable for patients with reduced LVEF who are already taking an ACEI and beta-blocker for symptomatic HF and who have persistent symptoms."
 * "A combination of hydralazine and a nitrate might be reasonable in patients with current or prior symptoms of HF and reduced LVEF who cannot be given an ACEI or ARB because of drug intolerance, hypotension, or renal insufficiency."
 * "The addition of isosorbide dinitrate and hydralazine to a standard medical regimen for HF, including ACEIs and beta-blockers, is reasonable and can be effective in blacks with NYHA functional class III or IV HF."

"Treatment with either type of drug should not be initiated in patients who have systolic blood pressures less than 80 mm Hg."

Isosorbide dinitrate and hydralazine combination treatment reduces mortality in African-American patients with functional class III or IV heart failure according to the A-HeFT randomized controlled trial. The number needed to treat is 26. The U.S. Food and Drug Administration has approved the drug BiDil for African Americans which has created controversy for reasons including the approval helped the manufacturer, NitroMed, add a second race-related patent that extended protection for BiDil for 13 years.

Whether the benefit to African-Americans is more than occurs for Anglo patients is unclear, but is suggested by two controversial post-hoc analyses of subgroups in the earlier  V-HeFT-1 and V-HeFT-2

In response to the results of the A-HeFT study, the American Heart Association clinical practice guidelines state "the effect of this combination of isosorbide dinitrate and hydralazine in other patients with HF who are undergoing standard therapy is not known because the population studied was limited to blacks, but there is no reason to believe that this benefit is limited to blacks."

Digitalis glycosides
Digitalis preparations are among the oldest drugs known to medicine. Due to the variability in preparations from the foxglove plant, synthetic digoxin is most commonly used. Digoxin was the agent used in the Digitalis Investigation Group trial, the only randomized clinical trial of digitalis in chronic HF. The principal motivation for use of these drugs in HF is their positive inotropic property, increasing the contractile ability of the heart.

An additional property relevant to HF, appears to be due to  neurohormonal suppressing properties. Digoxin is approved by both the U.S. Food and Drug Administration and the Canadian Cardiovascular Society for HF treatment.

Brain (B-type) natriuretic peptide
Nesiritide, a brain (B-type) natriuretic peptide, may help patients with decompensated congestive heart failure according to a randomized controlled trial. Natriuretic peptide causes diuresis, vasodilitation, and suppression of the renin-angiotensin system and sympathetic nervous system.

Vasopressin receptor inhibition
Tolvaptan, a vasopressin antagonist, may be beneficial according to a randomized controlled trial. Tolvaptan is a selective cell surface receptors V2 antagonist in the distal nephron which causes loss of free water. Other vasopressin antagonists act mainly on V1a cell surface receptors.

Noninvasive positive pressure ventilation
Noninvasive positive pressure ventilation (NPP) can help treat acute cardiac pulmonary edema according to a meta-analyses of randomized controlled trials. Among the different modes of NPPV, CPAP may be slightly better than BiPAP. It is not clear that NPPV helps patients with normal partial pressures of carbon dioxide.

Implantable devices
Several implantable devices may help long term treatment; however, it is not clear that implantable cardioverter-defibrillators (ICD) add benefit over cardiac resynchronisation therapy (CRT).

Cardiac resynchronization therapy
According to a systematic review, cardiac resynchronization therapy (CRT), which is biventricular pacing, can reduce morbiity and mortality if the ejection fraction is less than 35%. 30 patients must be treated to avoid one death (number needed to treat is 30). Cardiac resynchronization should only be used for patients with a QRS duration of at least 120 msec.

Implantable cardioverter-defibrillator
Implantable cardioverter-defibrillators (ICD) can reduce mortality in patients who have an ejection fraction of less than 35%.

Left ventricular assist devices
Left ventricular assist devices (LVADs) may be an option for patients with end stage heart failure.

Ultrafiltration
Ultrafiltration might help patients with cardiorenal syndrome.

Treatment of iron deficiency
Treating iron deficiency, even in the absence of anemia, may be beneficial according to a short randomized controlled trial.

Exercise
Exercise may improve self-reported health status and possibly combined mortality and hospitalization according to the HF-ACTION randomized controlled trial. Home based and center based cardiac rehabilitation may be equally effective.

Prognosis
Mortality can be predicted with the The Seattle Heart Failure Model, which has been independently validated. The model can show the affect of interventions on prognosis. The model is available online at http://depts.washington.edu/shfm/. Patients, especially younger patients, tend to overestimate their life expectancy.

Other risk factors
A prolonged QRS duration of 120 ms or more is associated with reduced survival.

Blood urea nitrogen adds a small, but significant amount to the Seattle Heart Failure Model.