DASH diet

The DASH diet is a popular eating plan proven to lower blood pressure. Promoted by the National Heart, Lung, and Blood Institute, the DASH diet is rich in fruits, vegetables, whole grains, fish, poultry, beans, seeds and nuts. It includes fat-free or low-fat milk and milk products, and is low in saturated fat, cholesterol, sodium, sweets and red meats.


Defibrillation involves the use of an electrical device to give an electric shock and help restore a normal heartbeat. It is used in cardiac arrest and for dangerous arrhythmias, or abnormal rhythms.


A defibrillator is a device that delivers electric shock to the heart when it has an abnormal rhythm (arrhythmia). External defibrillators include pads placed on the chest to deliver electric shock. Internal defibrillators (implantable cardioverter defibrillators, or ICDs) look similar to a pacemaker; they continuously monitor the heart rhythm to detect overly rapid arrhythmias such as ventricular tachycardia or ventricular fibrillation. The ICD corrects the heart rhythm by delivering precisely calibrated and timed electrical shocks to restore a normal heartbeat when one of these dangerous arrhythmias has occurred.


Diabetes is a condition that causes blood sugar to rise to dangerous levels. There are two main types of diabetes: type 1 and type 2. Both may be inherited, so a family history of diabetes can significantly increase a person's risk of developing the condition. If left untreated, diabetes can lead to blindness, kidney disease, nerve damage, heart disease and stroke.

diabetes educator

A diabetes educator is a healthcare provider who specializes in providing care and education to people with diabetes.

diabetic ketoacidosis

Diabetic ketoacidosis is an emergency condition in which extremely high glucose levels and a severe lack of insulin result in the breakdown of body fat for energy and an accumulation of ketones in the blood and urine. Symptoms of diabetic ketoacidosis are nausea and vomiting, stomach pain, fruity breath odor and rapid breathing. If untreated, diabetic ketoacidosis can lead to coma and death.

diastolic blood pressure

Diastolic blood pressure measures the lowest blood pressure in the arteries. The lowest blood pressure occurs when the heart muscle relaxes between beats. In a typical blood pressure reading, such as 120/78, the lower number is diastolic blood pressure and is measured in millimeters of mercury (mmHg).

diastolic dysfunction

Diastolic dysfunction is an abnormal function of the heart during its relaxation phase that compromises the heart’s ability to relax and fill. Filling of the heart’s lower chambers (ventricles) is impaired because the chamber is stiff due to thickening or cardiomyopathy. It may also be due to stiffening of the sac around the heart. Even though the ability to contract may be preserved, diastolic pressure is elevated and cardiac output reduced.

diastolic heart failure

Diastolic heart failure is a condition in which the heart’s pumping chambers (ventricles) become thickened, grow stiff and cannot relax enough to adequately fill the ventricles with blood. The fluid then backs up into organs and causes swelling or edema, especially in feet and ankles. It also causes congestion, even though the heart's pumping function is normal. Diastolic heart failure is caused by conditions such as acute ischemia, systolic hypertension with enlargement of the left ventricular muscle, restrictive cardiomyopathy and hypertrophic cardiomyopathy


Although the term diet is commonly used to describe a weight-loss plan, the primary definition is what a person eats and drinks. Diet plays a major factor in lowering your risk for heart disease and stroke. To keep your heart healthy and avoid those risks, the American Heart Association recommends a balanced diet low in added sugars, sodium and cholesterol.

dilated cardiomyopathy

Dilated or congestive cardiomyopathy is a condition in which the heart becomes weakened and enlarged and the pumping chambers contract poorly. Dilated cardiomyopathy is the most common form of cardiomyopathy. It occurs more frequently in men than in women, and most common between the ages of 20 and 60. The decreased heart function can affect the delivery of blood to the lungs, liver and other body systems.


A diuretic is a drug that increases the rate at which urine forms by promoting the excretion of water and salts. This helps to relieve the heart's workload and decreases the buildup of fluid in the lungs and other parts of the body. Different diuretics remove fluid at varied rates and through different methods. They can be used to treat high blood pressure, heart failure and some congenital heart defects.

drug-eluting stent (DES)

A stent is a wire mesh tube (scaffold) that’s inserted into a narrowed coronary artery to keep it open and allow heart muscle to get the blood flow and oxygen it needs. Drug-eluting stents have a coating that releases a drug over time to help keep blockages from happening.

drug interaction

A drug interaction occurs when there is a change in the effect of a drug when taken with another drug, a supplement or food. Its effect may increase or decrease, or side effects may occur.

Dual Antiplatelet Therapy (DAPT)

Dual anti-platelet therapy (DAPT) is the combination of an aspirin plus a P2Y12 inhibitor (ticagrelor, prasugrel, or clopidogrel). This treatment is prescribed to help prevent a future heart attack, stroke, clotting of the stent or artery (after coronary artery bypass graft (CABG) surgery).


Dysarthria is a condition in which speech is slowed, slurred or distorted due to muscular problems caused by damage to the brain or nervous system.


Dysphagia is difficulty chewing and swallowing because one side of the mouth is weak due to stroke or other brain injury. One or both sides of the mouth can lack feeling, increasing the risk of choking.


Dyspnea is a condition that causes difficult or labored breathing, often caused by heart conditions. Two types of dyspnea are significant in cardiac illness. Dyspnea on exertion is the shortness of breath that occurs with increasing activity. Paroxysmal nocturnal dyspnea is a shortness of breath that awakens a person from sleep. Both are significant symptoms in cardiac disease.

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