Final answer:
An implantable cardio-defibrillator is recommended for CHF patients at high risk of life-threatening arrhythmias such as ventricular fibrillation or tachycardia and for those with a history of these conditions. The device can deliver a shock to correct the rhythm and also work as a pacemaker to maintain regular heartbeats.
Step-by-step explanation:
An implantable cardio-defibrillator (ICD) is indicated in a patient with congestive heart failure (CHF) to correct life-threatening arrhythmias, such as ventricular fibrillation or ventricular tachycardia, which can lead to sudden cardiac death. These devices are particularly indicated for patients who have survived cardiac arrest due to ventricular fibrillation, have spontaneous sustained ventricular tachycardia, have syncope with inducible ventricular tachycardia or fibrillation during electrophysiological study, or have a significant risk of such arrhythmias like those with dilated cardiomyopathy and poor ejection fraction (<35%). An ICD continually monitors the heart rhythm and can deliver a shock of electrical energy to terminate an arrhythmia and restore normal sinus rhythm.
In addition to manual defibrillators used by healthcare professionals or automated external defibrillators (AED) designed for public use, implantable defibrillators are crucial for patients who experience these chronic, life-threatening arrhythmias. These sophisticated devices not only act to correct dangerous rhythm disturbances but can also function as a pacemaker, delivering electrical impulses to ensure that the heart continues to beat and pump blood effectively. In some cases, such as with heart failure patients at high risk, they are able to provide stimulation continuously or intermittently, as needed.