Some heart diseases give rise to defects in conduction of electrical signal from the generating place in the heart to all over the heart. Normally electrical signal for contraction of heart muscle is generated at one spot in the heart, and that traverses all over the heart to active all the muscle for systole or contraction of heart. This occurs in a rhythmical and regulated manner. A normal adult heart beats around 72times/minute.
If there is any conduction problem, heart may beat irregularly; sometime slowly and sometimes at a much higher rate. At times there occur ineffective contractions at a higher rate without any efficient pumping of blood called fibrillation. Sometimes heart chambers may also contract in a dissociated manner which is detrimental to life.
Image Conduction System (RED)
In these situations cardiologists put a device called implantable cardioverter defibrillator (ICD) under the skin of chest wall, and electrodes from there go to heart. It senses abnormality in contraction and delivers electrical shock of specified amplitude to stop heart from irregularities. That makes the heart function in a desired way.
If the device becomes faulty, that may endanger the life of the person. The conventional ICDs signal the patient once a day at a specified time about the functional status of the device. A device if at all goes wrong after that period that may give more shocks to heart which are undesirable and may actually prove to be detrimental. Inappropriate shocks are much more damaging, psychologically, than necessary electrical jolts.
The Lead Integrity Alert (LIA) software checks the device for suspicious electrical signals six times a day, and if problems are detected, alerts the patient with an audible beep every four hours, according to the study, which was published in the Sept. 27 issue of Circulation. Many electrophysiologists have started using the software soon after the FDA approved it in August 2008.
Researchers found that the patients who had standard monitoring, 70 percent received one or more inappropriate shocks, compared with only 38 percent of those who were monitored with the help of LIA software. Five or more inappropriate shocks were delivered to 50 percent of the patients who received standard monitoring, but only 25 percent of patients with LIA.
The researchers also found that 72 percent of patients with LIA had no inappropriate shock, or had at least three days warning prior to an inappropriate shock, compared with only 50 percent of those who received standard monitoring.
A faulty device needs to be replaced safely at appropriate time without giving more problems to a patient.