Preventing Heart Failure After Heart Attack

If you have had a myocardial infarction (MI), also known informally as a heart attack, your heart muscle has been damaged. If enough damage has been done, you may be at risk of developing heart failure, even if you had a mild MI that caused only minimal or moderate damage. (For people who have had a very large heart attack the risk of heart failure is acute and can occur within the first few hours or days of the MI).

Regardless of the extent of damage to the heart after a heart attack, appropriate drug therapy and lifestyle changes can be effective in delaying or preventing the onset of heart failure.

How the Heart Heals Itself

After a heart attack, the undamaged parts of the muscle stretch in an attempt to take over the work of the damaged muscle. (The clinical term for enlargement of the heart is cardiomegaly.)

As a result of this process, called "cardiac remodeling," the heart becomes larger. The cardiac enlargement allows the heart to eject a more normal volume of blood despite the fact that some of the muscle has been damaged, which is what contributes to the increased risk of heart failure after an MI.

To assess the health of the heart after an MI, a cardiologist typically will use a noninvasive imaging test. They include a multigated acquisition (MUGA) scan or an echocardiogram to determine what is known as the left ventricle ejection fraction (LVEF).

Preventing Cardiac Remodeling

After a heart attack, you will likely be prescribed one or more of the medications known to significantly reduce remodeling after an MI, thereby improving survival rates for people who have signs of impending heart failure. These drug classes include:

• Beta blockers
• Angiotensin receptor blockers (ARBs)
• Angiotensin-receptor neprilysin inhibitor (ARNIs)
• Angiotensin-converting enzyme (ACE) inhibitors

Beta blockers work by blocking the effect of adrenaline on the heart. Most people who've had an MI should be given a beta blocker, with the exception of those with severe asthma or other lung disease. Side effects of beta blockers include fatigue, dizziness, poor circulation, gastrointestinal symptoms, sexual dysfunction, and weight gain.

ACE inhibitors are believed to help prevent or delay remodeling after a heart attack, thereby lowering the risk of a recurrent MI, stroke, or sudden death. They're known to significantly improve long-term survival.

Among the side effects of ACE inhibitors are cough, low blood pressure, dizziness, rashes, gastrointestinal upset, and deterioration of kidney function. People who should not take ACE inhibitors include pregnant women, people with severe kidney disease, people with elevated potassium levels, and those who have allergic reactions resulting in swelling.

ARNi therapy combines ARB benefits (lowered blood pressure and opened blood vessels) with a drug to limit the activity of an enzyme called neprilysin. It helps to boost the ARB benefits while decreasing the heart's workload. Studies suggest it can limit remodeling in people diagnosed with heart failure.

Maintaining Cardiac Health

Key to keeping your heart healthy and preventing another cardiac event will be how you live your daily life. This may mean making significant changes in your diet, activity levels, and certain habits that impact heart health:

• Quit smoking. Smoking accelerates the development of atherosclerosis by increasing levels of bad cholesterol (LDL) and reducing levels of good cholesterol (HDL) in the blood. It also speeds up the heart rate, elevates blood pressure, and increases the tendency of blood to form clots.
• Improve your diet. Focus on a heart-healthy diet maximizes vegetables, fruits, whole grains, low-fat dairy products, poultry, fish, legumes, non-tropical vegetable oils, and nuts. Limit consumption of red meat, sweets, processed foods, and sodas.
• Exercise. Research has shown that at least 150 minutes per week of moderate-intensity physical activity can help lower blood pressure and cholesterol as well as keep your weight down. If you've been diagnosed with heart failure, first discuss your exercise goals with your healthcare provider.
• Lose weight if you are overweight. Obesity puts you at risk for high cholesterol, high blood pressure, and insulin resistance, a precursor of type 2 diabetes. These factors increase your chances of developing cardiovascular disease.
• Lower your blood pressure. An optimal blood pressure reading is less than 120/80 mmHg. You can get there by taking your blood pressure medications as prescribed, exercising, and reducing your sodium intake.
• Keep diabetes under control, if you have it. At least 68% of people under age 65 with diabetes die of some form of heart disease.
• Manage stress. Research has tied chronic stress to inflammation that may contribute to coronary artery disease.
• Limit alcohol. Drinking too much can raise blood pressure, increase cardiomyopathy, contribute to high triglycerides, and produce irregular heartbeats. Alcohol in moderate quantities may provide some benefit to the heart. Moderate is no more than one drink a day for women and two drinks for men. A drink is defined as 5 ounces of wine or 12 ounces of regular beer.
• Take care of your teeth. Studies suggest gum disease (gingivitis) may increase the risk of heart disease and stroke because of the high levels of bacteria in infected areas of the mouth. Inflammation of the gums may also increase inflammation in other parts of the body.
• Get enough sleep. Sleep deprivation is a significant risk factor for heart disease. In the evening of the day after sleep deprivation, sympathetic nervous system activity and blood pressure rise, and that increase is associated with an increased risk for coronary disease.

Although you can't change the fact that you've had a heart attack, with some attention to your medications, lifestyle, and diet, you can likely prevent another and slow the progression of heart disease.