Intended Uses

The implantable cardioverter defibrillator is indicated for use in patients who are at high risk of sudden cardiac death due to ventricular tachyarrhythmias and who have experienced one of the following situations: (a) Survival of at least one episode of cardiac arrest (manifested by the loss of consciousness) due to ventricular tachyarrhythmias. (b) Recurrent, poorly tolerated sustained ventricular tachycardia (VT). (Note: the clinical outcome for hemodynamically stable VT patients is not fully known. Safety and effectiveness studies have not been conducted.

Contraindications

Use of the device is contraindicated in: (a) Patients whose ventricular tachyarrhythmias may have transient or reversible causes such as acute myocardial infarction, digitalis intoxication, drowning, electrocution, electrolyte imbalance, hypoxia, sepsis, or transient ischemic episodes (b) Patients with incessant tachyarrhythmia (c) Patients who have a unipolar pacemaker (d) Patients whose primary disorder is bradyarrhythmias or atrial tachyarrhythmias (e) Dual chamber and single chamber atrial pacing is contraindicated with chronic refractory atrial tachyarrhythmias.

Warnings and Precautions

Do not perform the device testing unless an external defibrillator and medical personnel skilled in cardiopulmonary resuscitation (CPR) are readily available. Do not permit the patient to contact grounded equipment that could produce hazardous leakage current. Program shock therapy to OFF during surgical implant and explant or post-mortem procedures. Be aware that the changes in the patient's condition, drug regimen, and other factors may change the defibrillation threshold (DFT), which may result in non-conversion of the arrhythmia post-operatively. Patients should be directed to avoid devices that generate a strong electric or magnetic interference (EMI). External defibrillation may damage the generator or may result in temporary and/or permanent myocardial damage at the electrode-tissue interface as well as temporary or permanent elevated pacing thresholds. Magnetic resonance imaging (MRI) may cause device malfunction or damage. If MRI must be used, patients should be closely monitored and programmed parameters should be verified upon cessation of MRI.

Side Effects

Potential side effects include, but are not limited to: lead migration or dislodgment, pocket infection or hematoma, ventricular oversensing, inappropriate therapy, ineffective therapy, pneumothorax, prolonged implant procedure, and change in sensing or pacing thresholds.

Refer to the physician's manual for a complete statement of intended uses, relevant warnings, precautions, side effects, and contraindications.