Congestive heart failure treatment of patients with cardiac structural abnormalities or remodeling who have not developed heart failure symptoms (Stage B)


 * Saleh El Dassouki, M.D. [mailto:seldassouki@hotmail.com];

Overview
Patients who have had an myocardial infarction or evidence of left ventricular remodeling are at considerable risk of developing heart failure even if they do not present with any symptoms of heart failure. Reducing the risk of additional injury and retarding the evolution and progression of LV remodeling is thus very important in considerably decreasing the incidence of heart failure. Initial appropriate measures include those listed as Class 1 recommendations for patients in Stage A.

The use of nutritional supplements in patients with a recent or remote MI with or without LV remodeling has not been proved to reduce the risk of heart failure. The aldosterone antagonist eplerenone on the other hand has been shown to reduce morbidity and mortality in patients with low ejection fraction and heart failure after an MI that has already been treated with ACEIs and beta blockers.

Patients with an Acute MI
Various procedures such as the infusion of a fibrinolytic agent or the use of percutaneous coronary intervention can reduce the risk of death and development of heart failure in patients who are experiencing an acute MI. Administration of beta blockers combined with ACEIs or ARB in patients with acute MI can decrease the risk of reinfarction or death when initiated within days after the ischemic event, especially in patients whose course is complicated by HF; Those drugs can be administered separately, but the neurohormonal blockade achieved by the combination previously mentioned (beta blockers and ACEIs or ARB) has been demonstrated to produce additive benefits.

Patients With History of MI but Normal Left Ventricular Ejection Fraction
A history of MI, even in patients with normal left ventricular ejection fraction should prompt a vigorous treatment of both hypertension and hyperlipidemia, because of their immense benefit in decreasing the risk of further left ventricular dysfunction especially in patients with a prior ischemic event. Patient with a recent MI should also be treated with ACEIs and beta blockers, which have been proven to reduce the risk of death when started days or weeks after an ischemic cardiac event. Evidence from 2 other large-scale studies has shown that long term therapy with an ACEI can also decrease the risk of a major cardiovascular event, even when treatment is initiated months or years after MI. .

Patients with Chronic Reduction of Left Ventricular Ejection Fraction but No Symptoms
As previously discussed, long term treatment with an ACEI have been shown to reduce the risk of HF in patients with ischemic cardiac events without left ventricular dysfunction. This is also true in case of asymptomatic patients with reduced left ventricular function, whether due to a remote ischemic injury or to a nonischemic cardiomyopathy. The usage of ARBs in asymptomatic patients with reduced LVEF have not been fully studied yet and has not been implemented in the treatment of those patients. On the other hand, asymptomatic patients with a low EF have benefited from treatment with ARBs according new studies, particularly in patients who cannot tolerate ACEI. Another important agent recommended in the management of patients with a low EF and no symptoms (especially patients with history of CAD) is beta blockers, although adequate controlled clinical trials are lacking to fully support this recommendation.

No data have been obtained to date to recommend Digoxin in asymptomatic patients with reduced LVEF, except in those with Atrial Fibrillation; the reason behind this, is that Digoxin has only a minimal effect on disease progression in symptomatic patients, so it is unlikely that the drug would be beneficial in those with no symptoms. Calcium Channel Blockers are not recommended as well in patients with asymptomatic reduction of LVEF, but they have not been shown to have adverse effects and may be helpful for the management of concomitant conditions such as hypertension. However, the usage of calcium channel blockers with negative inotropic effects in patients with EF below 40% after MI is not recommended.

Patients whose cardiomyopathy is associated with a rapid arrhythmia of supraventricular origin (e.g. atrial flutter or atrial fibrillation) should be closely monitored because such arrhyhmias may contribute to a further impairment of ventricular function and may either induce or exacerbate the development of cardiomyopathy.

Asymptomatic Patients With Valvular Heart Disease
Patients with severe aortic or mitral valve stenosis or insufficiency should be considered for valvular replacement or surgical repair. Poor surgical candidates should be considered for TAVI. Long term therapy with vasodilators as hydralazine and nifedipine has not yet been proven to reduce risk of HF or death in long term studies, however patients with severe aortic insufficiency and preserved LV function may benefit from such treatment to minimize structural changes in the ventricle but these drugs are usually poorly tolerated in this setting. There are no trial or long term studies which prove that these vasodilators are beneficial in severe mitral insufficiency.

==ACC/AHA Guidelines- Treatment of Patients With Cardiac Structural Abnormalities or Remodeling who have not Developed Heart Failure Symptoms (Stage B) == {{cquote|

Class I
1. All Class I recommendations for Stage A should apply to patients with cardiac structural abnormalities who have not developed HF. (Levels of Evidence: A, B, and C as appropriate)

2. Beta-blockers and ACEIs should be used in all patients with a recent or remote history of MI regardless of EF or presence of HF. (Level of Evidence: A)

3. Beta-blockers are indicated in all patients without a history of MI who have a reduced LVEF with no HF symptoms. (Level of Evidence: C)

4. Angiotensin converting enzyme inhibitors should be used in patients with a reduced EF and no symptoms of HF, even if they have not experienced MI. (Level of Evidence: A)

5. An ARB should be administered to post-MI patients without HF who are intolerant of ACEIs and have a low LVEF. (Level of Evidence: B)

6. Patients who have not developed HF symptoms should be treated according to contemporary guidelines after an acute MI. (Level of Evidence: C)

7. Coronary revascularization should be recommended in appropriate patients without symptoms of HF in accordance with contemporary guidelines (see ACC/AHA Guidelines for the Management of Patients With Chronic Stable Angina). (Level of Evidence: A)

8. Valve replacement or repair should be recommended for patients with hemodynamically significant valvular stenosis or regurgitation and no symptoms of HF in accordance with contemporary guidelines. (Level of Evidence: B)

Class IIa
1. Angiotensin converting enzyme inhibitors or ARBs can be beneficial in patients with hypertension and LVH and no symptoms of HF. (Level of Evidence B)

2. Angiotensin II receptor blockers can be beneficial in patients with low EF and no symptoms of HF who are intolerant of ACEIs. (Level of Evidence: C)

3. Placement of an ICD is reasonable in patients with ischemic cardiomyopathy who are at least 40 days post-MI, have an LVEF of 30% or less, are NYHA functional class I on chronic optimal medical therapy, and have reasonable expectation of survival with a good functional status for more than 1 year. (Level of Evidence: B)

Class IIb
1. Placement of an ICD might be considered in patients without HF who have nonischemic cardiomyopathy and an LVEF less than or equal to 30% who are in NYHA functional class I with chronic optimal medical therapy and have a reasonable expectation of survival with good functional status for more than 1 year. (Level of Evidence: C)

Class III
1. Digoxin should not be used in patients with low EF, sinus rhythm, and no history of HF symptoms, because in this population, the risk of harm is not balanced by any known benefit. (Level of Evidence: C)

2. Use of nutritional supplements to treat structural heart disease or to prevent the development of symptoms of HF is not recommended. (Level of Evidence: C)

3. Calcium channel blockers with negative inotropic effects may be harmful in asymptomatic patients with low LVEF and no symptoms of HF after MI (Patients in Stage C). (Level of Evidence: C)}}

Vote on and Suggest Revisions to the Current Guidelines

 * The CHF Living Guidelines: Vote on current recommendations and suggest revisions to the guidelines

Guidelines Resources

 * The ACC/AHA 2005 Guideline Update for the Diagnosis and Management of Chronic Heart Failure in the Adult


 * 2009 focused update: ACCF/AHA Guidelines for the Diagnosis and Management of Heart Failure in Adults: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines: developed in collaboration with the International Society for Heart and Lung Transplantation