Cardioversion is synchronized delivery of direct current energy (typically to the chest), but potentially directly to the myocardium by internal catheters.
Wolff-Parkinson-White (WPW) syndrome is defined by a short PR interval on ECG (less than 120 milliseconds) with the presence of a delta wave (slurred segment between the P wave and QRS complex) and a history of palpitations/supraventricular tachycardia. Preexcitation (a delta wave on an ECG) exists in approximately 0.15 percent of the general population.
Ventricular tachycardia, as well as ventricular fibrillation, is a leading cause of sudden cardiac death worldwide. Most people who die suddenly are not experiencing acute myocardial infarction. In fact, only 20 percent of patients who experienced sudden death suffered from acute myocardial infarction.
In a patient with congenital long QT syndrome (LQTS), the 12-lead ECG may show prolongation of the corrected QT (QTc) interval. A normal baseline QTc interval of less than or equal to 0.44 seconds does not exclude LQTS; in fact, this may be observed in approximately 12 percent of genetic carriers of this condition.
Syncope (or loss of consciousness) is one of the most frequent emergency room and hospital diagnoses. Syncope or near-syncope is responsible for 1 percent to 6 percent of hospital admissions and/or emergency room visits. The workup should follow a simple algorithm.
Congestive heart failure (CHF) has become one of the most common diseases in the United States. Over 5 million people in the United States are living with CHF, and over 650,000 new cases are diagnosed each year.
The most recent Centers for Medicare and Medicaid Services and the National Coverage Determination for Cardiac Pacemakers (20.8.3) is looking for a direct correlation between a patient’s symptoms and an irreversible conduction disorder.
One of the greatest inventions of the modern era has been the implantable cardioverter-defibrillator (ICD). Envisioned by Michel Mirowski and Morton Mower in the late 1970s and early 1980s, this device was initially very large, requiring an open-chest implant and a 10-day hospital stay.
Congestive heart failure affects over 5 million people in the United States, with an annual incidence of over 650,000 new cases a year.
Implanted pacemaker and defibrillator leads may occasionally require explantation in order to remove infected hardware or make room for newer leads.