Defibrillation is the use of strong but controlled electric shocks to return the heart to a normal rhythm of contractions. Defibrillation is used when the ventricles of patient's heart are beating too quickly or erratically to effectively pump blood (ventricular fibrillation). The electrical shocks are applied by a machine called a defibrillator either through electrodes on the chest wall of a patient, or directly to the patient's heart. See also Automatic Implantable Cardiac Defibrillators, AICDs.
Descending Aorta
The descending aorta begins after the aorta arches over the heart. The descending aorta travels down along the spine. The section of the descending aorta from the aortic arch to the diaphragm is also called the thoracic aorta. The section of the descending aorta below the diaphragm is also called the abdominal aorta.
Diastole
The period of diastole is when the ventricle relaxes between contractions. When a patient's blood pressure is taken, the diastolic pressure, or the measurement of this resting period, is the second figure given. An average diastole lasts roughly 0.5 seconds for a heart rate of 70 beats per minute.
Directional Coronary Atherectomy (Dca)
A directional coronary atherectomy is similar to an angioplasty except that the blockage is decreased by mechanically removing the plaque.
Dressler's Syndrome
See cardiotomy syndrome.
Drug-Eluting Stent
Drug-eluting stent refers to a stent with an active drug that is intended to produce a therapeutic effect (e.g., reduction of restenosis).
