心脏起搏及ICD适应征讲义.pptVIP

* Candidates for pacemaker implantation may present with any of the above symptoms or conditions. * In a bipolar system, body tissue is part of the circuit only in the sense that it affects impedance (at the electrode-tissue interface). In a unipolar system, contact with body tissue is essential to ground the IPG and allow pacing to occur. * * The American College of Cardiology and the American Heart Association have determined guidelines for pacemaker implantation. These 1998 guidelines are divided into three classes. Class II has subcategories A and B. Gregoratos G, et al. ACC/AHA guidelines for Implantation of cardiac pacemakers and antiarrhythmia devices: a report of the ACC/AHA Task Force on Practice Guidelines (Committee on Pacemaker Implantation). J Am Coll Cardiol. 1998:31; 1175-1206. * In addition to classification, recommendations that are evidence based were added to descriptions. For example: Class I indication for symptomatic third-degree AV block was designated with a 搇evel of evidence: C? For the sake of brevity, this presentation will not include evidence based recommendations. For a complete listing of recommendations, consult JACC , April 1998. Gregoratos G, et al. ACC/AHA guidelines for Implantation of cardiac pacemakers and antiarrhythmia devices: a report of the ACC/AHA Task Force on Practice Guidelines (Committee on Pacemaker Implantation). J Am Coll Cardiol. 1998:31; 1175-1206. * Class I Indication(s): 1. Documented symptomatic sinus bradycardia, including frequent sinus pauses that produce symptoms. May be due to long-term drug therapy of a type and dose for which there is no accepted alternative 2. Symptomatic chronotropic incompetence (of the sinus node) Class II Indication(s): 1a. Symptomatic patients with sinus node dysfunction and documented rates of 40 bpm without a clear-cut association between significant symptoms and the bradycardia 1b. In minimally symptomatic patients, chronic heart rate 30 bpm while awake Cl