Pacemaker and Cardioverter-Defibrillator Implantation (also see Chapter 35 )

Permanent pacemakers and permanent ICDs are frequently implanted in the cardiac catheterization laboratory. Implantation of both devices involves placement of transvenous leads into the cardiac chambers (usually the right atrium or ventricle or both) with tunneling of the leads to a subcutaneous pocket in which the device is placed. The discomfort of the procedure can be reduced with local anesthesia, and many of these procedures are performed with sedation/analgesia. General anesthesia is necessary during testing of the permanent cardioverter-defibrillator. When the ICD is tested, ventricular tachycardia or fibrillation is induced, and the ability of the device to sense the arrhythmia and deliver appropriate cardioversion-defibrillation energy is confirmed. Many patients undergoing ICD placement have poor ventricular function. Return of hemodynamic variables to baseline after cardioversion-defibrillation must be closely monitored. It is our practice to place radial arterial catheters for continuous blood pressure monitoring in patients with a history of hemodynamic instability, as well as in all patients with a documented left ventricular ejection fraction less than 20%.