Treating Heart Failure Due to Dilated Cardiomyopathy

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The treatment of dilated cardiomyopathy (DCM) — the most common form of heart failure — has improved dramatically over the past several years.

Unfortunately, studies show that many patients with DCM are not receiving the treatments they ought to be receiving. For this reason, it is important for you to be aware of the treatments recommended for DCM — if only to make sure your doctor is covering all the bases.

Treat the Underlying Cause

The first rule in treating DCM is to identify and treat the underlying cause. Treating the underlying cause can often slow, stop, or even reverse the progression of DCM. You can read here about the many causes of DCM.

Drug Treatment of DCM

Beta blockers. Beta blockers reduce the excess stress on the failing heart, and have been proven to significantly improve the overall heart function, symptoms, and survival of patients with DCM. Beta blockers are now considered a mainstay in treating DCM. Coreg (carvedilol), Toprol (metoprolol), and Ziac (bisoprolol), are the beta blockers most commonly used in DCM, but several others are also available.

Diuretics. Diuretics, or "water pills," are a mainstay of therapy for people with heart failure. These drugs increase water elimination through the kidneys and reduce the fluid retention and edema that often occurs in DCM. Commonly used diuretics include Lasix (furosemide) and Bumex (bumetanide).

Their chief side effect is that they can cause low potassium levels, which can lead to cardiac arrhythmias.

ACE inhibitors. ACE inhibitors (drugs that block angiotensin converting enzyme) have proven to be very effective in improving both the symptoms and survival in patients with heart failure. The chief side effects are cough or low blood pressure, but most people with DCM tolerate ACE inhibitors well.

Commonly used ACE inhibitors include Vasotec (enalapril), Altace (ramipril), Accupril (quinapril), Lotensin (benazepril) and Prinivil (lisinopril).

Angiotensin II receptor blockers (ARBS). ARBS are drugs that work similarly to ACE inhibitors. They can be used in people with DCM who cannot take ACE inhibitors. ARBS that have been approved for heart failure include Atacand (candesartan) and Diovan (valsartan).

Aldosterone antagonists. Aldactone (spironolactone) and Inspra (eplerenone) are aldosterone antagonists, another class of drugs convincingly shown to improve survival in some people with heart failure. When they can be used safely, one of these drugs is generally recommended, in addition to ACE inhibitors (or an ARB drug) and beta blocker, in people with DCM. However, if the patient has reduced kidney function, these drugs can cause significant hyperkalemia (high potassium levels). Aldosterone antagonists need to be used with great caution, if at all, when kidney function is not normal.

Hydralazine plus nitrates. In people with DCM who have persistent symptoms despite beta-blockers, ACE inhibitors, and diuretics, combining hydralazine plus an oral nitrate (such as isosorbide) can significantly improve outcomes.

Neprilysin inhibitor. The first of the neprilysin inhibitors (a new class of drugs), was approved for the treatment of heart failure by the FDA in 2015. This drug, Entresto, is actually a combination of an ARB (valsartan) with a neprilysin inhibitor (sacubitril). Early studies with Entresto have been quite promising, and some experts believe it ought to be used in place of an ACE inhibitor or ARB. However, experience with the drug remains limited and long-term side effects are still a question mark. Also, the drug is very expensive. So in general its usage today is mainly in patients who cannot tolerate or fail to respond adequately to ACE inhibitors or an ARB.

As more experience with Entresto is accumulated, its usage will very likely increase. 

IvabradineIvabradine is a drug that is used to slow the heart rate. It is used in conditions like inappropriate sinus tachycardia, where the heart rate is inappropriately elevated. People with DCM also can have resting heart rates that are substantially higher than is considered normal, and there is evidence that reducing that elevated heart rate with ivabradine may improve outcomes. Most cardiologists consider using ivabradine in people who are on maximal therapy with other drugs (including a beta blocker) and who still have a resting heart rate above 70 beats per minute.

Digoxin. While in past decades digoxin was considered a mainstay in treating heart failure, its actual benefits in treating DCM now seem to be marginal. Most doctors prescribe it only if the more effective medications do not appear to be adequate.

Inotropic drugs. Inotropic drugs are intravenous medications that push the heart muscle to work harder, and thus to pump more blood. Years ago there was a lot of enthusiasm for these drugs, as they almost always produce an immediate improvement in cardiac function. Two inotropic drugs in particular (milrinone and dobutamine) came into fairly widespread use in stabilizing people with acute heart failure, and were also used in the long-term therapy of some people with severe heart failure. However, subsequent studies showed that people treated with inotropic drugs — despite the symptomatic improvement they often experienced — had significantly increased mortality. These drugs are now used very infrequently, and only in people with very severe heart failure who have failed to respond to multiple other treatments.

Cardiac Resynchronization Therapy

Cardiac resynchronization therapy (CRT) is a form of cardiac pacing that stimulates both ventricles (right and left) simultaneously. (Standard pacemakers stimulate only the right ventricle.) The purpose of CRT is to coordinate the contraction of the ventricles, in order to improve the efficiency of the heart. Studies with CRT show that this therapy, in appropriately selected patients, results in substantial improvements in cardiac function and symptoms, reduces hospitalizations, and prolongs life. Any patient with DCM and a significant bundle branch block should be considered for CRT.

Implantable Defibrillator Therapy

Unfortunately, people with moderate to severe DCM have an increased risk of sudden cardiac death from ventricular arrhythmias. The implantable cardioverter defibrillator (ICD) has been shown to significantly reduce mortality in certain people with DCM who have significantly reduced left ventricular ejection fractions. If you have DCM, you should discuss with your doctor whether an ICD is something that ought to be considered in your case.

Cardiac Transplantation

Success with cardiac transplantation has improved remarkably over the last several decades. However, due to the drastic nature of the therapy, and to the fact that donor hearts are in very short supply, heart transplantation is reserved for the very sickest patients with heart failure. It is noteworthy, however, that most heart transplant centers have found that many patients referred to them with "end-stage heart failure" have actually never received the aggressive heart failure therapy they need — and when aggressive therapy is instituted they improve substantially and no longer require heart transplantation.

Experimental Therapy

A lot of research is being done to determine whether gene therapy or stem cell therapy might be beneficial in people with DCM. While both of these experimental treatments show some promise, they are very early in the evaluation process, and are not generally available for patients with DCM. 

A Word From Verywell

Studies continue to show that a majority of people with heart failure due to DCM are not receiving all the therapy they ought to be receiving. For this reason, if you or a loved one has this condition you should make sure you are familiar with all the recommended treatments, and that you discuss them with your doctor.

Sources:

Task Force for Diagnosis and Treatment of Acute and Chronic Heart Failure 2008 of European Society of Cardiology, Dickstein K, Cohen-Solal A, et al. ESC Guidelines for the Diagnosis and Treatment of Acute and Chronic Heart Failure 2008: the Task Force for the Diagnosis and Treatment of Acute and Chronic Heart Failure 2008 of the European Society of Cardiology. Developed in collaboration with the Heart Failure Association of the ESC (HFA) and Endorsed by the European Society of Intensive Care Medicine (ESICM). Eur Heart J 2008; 29:2388.

Yancy CW, Jessup M, Bozkurt B, et al. 2013 ACCF/AHA Guideline for the Management of Heart Failure: Executive Summary: a Report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines. Circulation 2013; 128:1810.

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