Internal Cardioverter Defibrillator

The use of antiarrhythmic drugs in the United States is declining because of major trials that show increased mortality with their use in several clinical situations, the realization of proarrhythmia as a significant side effect, and the advancing technology of nondrug therapies such as ablation and the internal cardioverter-defibrillator. 

Patients with hemodynamically significant ventricular tachycardia or ventricular fibrillation not associated with an acute Ml who are resuscitated successfully (electrical cardioversion, pressors, amiodarone) are at high risk for death and should receive implantation of an internal cardioverter-defibrillator. 

LQTS = long-QT syndrome SD = sudden death TdP = torsade de pointes PMVT = polymorphic ventricular tachycardia VF = ventricular fibrillation BB = j6-blocker ICD = internal cardioverter-defibrillator. 

Biomaterials have played a vital role in the treatment of cardiovascular diseases, examples of applications including heart valve prostheses, vascular grafts, stents, indwelling catheters, ventricular assist devices, total implantable artificial heart, pacemakers, automatic internal cardioverter defibrillator, intraaortic balloon pump, and more. A key requirement for materials in cardiovascular applications, particularly blood-contacting devices, is blood compatibility, that is, nonthrombogenic. Additional requirements include mechanical and surface properties that are application specific. Surveying the field of polymers used in cardiovascular applications reveals that PUs, polyethylene terephthalate (PET), and expanded PTFE (ePTFE) are the most commonly used. This section will review each of the three polymers followed by a brief introduction of other emerging polymers for use in the cardiovascular area. 

In patients who have experienced VT and are at risk for sudden cardiac death, implantation of an implantable cardioverter-defibrillator (ICD) is the treatment of choice.44 An ICD is a device that provides internal electrical cardioversion of VT or defibril -lation of VF the ICD does not prevent the patient from developing the arrhythmia, but it reduces the risk that the patient will die of sudden cardiac death as a result of the arrhythmia. Whereas in the past ICD implantation required a thoracotomy, these devices now may be implanted transvenously, similarly to pacemakers, markedly reducing the complication rate. 

Implantable cardioverter-defibrillator (ICD) A device implanted into the heart transvenously with a generator implanted subcutaneously in the pectoral area that provides internal electrical cardioversion of ventricular tachycardia or defibriUation of ventricular fibrillation. 

Ezekowitz JA, Armstrong PW, McAlister FA. Implantable cardioverter defibrillators in primary and secondary prevention a systematic review of randomized, controlled trials. Ann Intern Med. Mar 18 2003 138(6) 445-452. 

Uslan DZ, Sohail MR, St Sauver JL et al (2(X)7) Permanent pacemaker and implantable cardioverter defibrillator infec-tion a population-based study. Arch Intern Med 167 669-675... 

Fig 5 14 (a-d) Temporal-sequence fluoroscopic images (same patient as in Figure 5.8) after exposure of the atrial lead from the internal jugular vein showing introduction and sheath advancement over the lead, overcoming binding sites to the tip. (e-h) The same maneuver on an implantable cardioverter-defibrillator (ICD) ventricular lead... 

Mond HG, Irwin M, Ector H, Proclemer A (2008) The world survey of cardiac pacing and cardioverter-defibrillators calendar year 2005 an International Cardiac Pacing and Electrophysiology Society (ICPES) project. Pacing Clin Electrophysiol 31(9) 1202-1212... 

Bardy GH, Yee R, The International Active Can Investigators. World wide experience with the Jewel 7219C unipolar, single lead active can implantable pacer-cardioverter/defibrillator. PACE 1995 18(II) 806. 

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