defibrillation An electric shock administered to the heart to stabilize an irregular heartbeat or restore a normal heartbeat after cardiac arrest.
diabetes A disorder characterized by problems in glucose (blood sugar) metabolism. There are two forms of diabetes: Type I (also called juvenile-onset or insulin-dependent diabetes), in which the body ceases to produce insulin (the hormone essential for glucose metabolism); and Type 11 (also called adult-onset or insulin-resistant diabetes), in which the body fails to utilize insulin effectively.
diastolic The lower of the two numbers recorded when a person’s blood pressure is taken. It represents the arterial pressure when the heart’s pumping chambers (ventricles) are relaxed between beats and refilling with blood.
dietitian A health professional trained in the field of
dietetics The science dealing with nutrition and health.
digitalis A drug derived from the foxglove plant and used in the treatment of heart failure and abnormal heart rhythms. Digitalis works by strengthening the pumping action of the heart, thereby improving blood circulation, or by slowing down some of the electrical impulses from the atria to the ventricles. The most commonly used form of this drug is digoxin.
dilated cardiomyopathy A disorder in which muscle cells in the walls of the heart do not function normally; the walls enlarge and dilate, and heart failure develops.
dissecting aneurysm A condition in which blood is forced through a fissure or tear in an artery’s inner wall and remains between the layers of its lining, causing the vessel to bulge.
diuretics Medications used to treat fluid retention by increasing the kidney’s output of urine and the excretion of sodium from the body. Effective in the treatment of hypertension and heart failure.
dyspepsia The medical term for indigestion.
dyspnea Shortness of breath or difficulty breathing.