Cardiac pacemaker implanted

It is unclear whether topiramate played any role in rare cardiovascular events. These included symptoms of Raynaud s phenomenon in three patients, and third-degree atrioventricular block requiring emergency cardiac pacemaker implantation in one patient with preexisting right bundle branch block (SEDA-21, 76). 

Cardiac catheterization, including balloon angioplasty Implanted cardiac pacemakers, implanted defibrillators, and coronary stents... 

Hayes DL, Vliestra RE, Trusty JM, et al. A shorter hospital stay after cardiac pacemaker implantation. Mayo Clin Proc 1988 63 236. 

Muers MF, Arnold AG, Sleight P. Prophylactic antibiotics for cardiac pacemaker implantation a prospective trial. Br Heart J 1981 46 539. 

Even more severe than the diseases leading to cardiac pacemaker implantation is the sudden cardiac death (SCO). It is the most often reason for death in western industrial countries and accounts for 1200 deaths per day in the USA. SCD is caused by ventricular tachycardia or fibrillation and death occurs within minutes. The only possibility to overcome the tachycardia and to induce a regular heart beat is to delibrillate the heart. In these cases, instead of a normal cardiac pacemaker, a different implant has to be applied. Implantable cardioverter-defibrillators (ICD) have been developed in the 1980s and more than 25 000 devices have been implanted worldwide up to the mid... 

His blood pressure fluctuates, causing orthostatic hypotension. A severe syncopal episode 2 years ago necessitated a cardiac pacemaker implant, at which time he was also found to have infiltrative cardiomyopathy, a known concomitant of mutant-TTR amyloidosis. Heart transplant has been considered. 

Worldwide, more than 250,000 cardiac pacemakers were implanted in 1995, accounting for well in excess of 1 biUion in sales. It is estimated that over 500,000 people in the United States alone have pacemakers. Millions of people have been able to lead normal lives thanks to this remarkable device. 

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. 

Furthermore, pH determination has been used in other clinical research, both alone and in combination with other measurements. This research includes studies into the relationship between extracellular and intracellular pH in an ischemic heart [6, 7], the pH of airway lining fluid in respiratory disease [8], the study of pH as a marker for pyloric stenosis [9], malnutrition in alkalotic peritoneal dialysis patients [10], pH modulation of heterosexual HIV transmission [11, 12], and wound prevention and treatment [13], In addition, pH changes due to blood acidosis have been used to trigger and pace the ventricular rate of an implanted cardiac pacemaker [14], Research using pH measurements... 

Lithium iodide is the electrolyte in a number of specialist batteries, especially in implanted cardiac pacemakers. In this battery the anode is made of lithium metal. A conducting polymer of iodine and poly-2-vinyl pyridine (P2VP) is employed as cathode because iodine itself is not a good enough electronic conductor (Fig. 2.3a). The cell is fabricated by placing the Li anode in contact with the polyvinyl pyridine-iodine polymer. The lithium, being a reactive metal, immediately combines with the iodine in the polymer to form a thin layer of lithium iodide, Lil, which acts as the electrolyte ... 

Coagulation is not the only problem with materials intended for implantation, however. Cardiac pacemakers are intended to correct arrhythmias. Insulating materials for a pacemaker lead must be tough and long lasting. The first leads were insulated with polyethylene or silicone rubber. Neither material was considered ideal because of endocardial reactions (polyethylene) and limited durability (silicone rubber). The strength and flexibility of polyurethanes led to their introduction in 1978 as lead insulators. 

The high reliability and the complete absence of faults such as electrolyte leakage or gas generation make the lithium-iodine solid state battery a particularly suitable device for powering implanted electronic devices, and it is now widely used in the cardiac pacemaker industry. The design and construction of Medtronic Inc, pacemaker batteries are shown in Fig. 9.12. A typical unit, such as the Enertec Alpha 33 , has dimensions of 33.4 mm X 27.4 mm X 7.9 mm, giving a total volume of 6.0 cm3 and a mass of 22 g. The cell has a completely welded construction and uses a specialized... 

At the end of this chapter, some readers may wonder why we did not present one of the three most famous and beneficial neural prostheses that are in clinical use since several years the cardiac pacemaker, the cochlea implant and the urinary bladder stimulator of Brindley. In our view, the devices may not be considered microsystems. Only the electronic parts are built of monolithic integrated circuitry in silicon technology. The electrodes are still manufactured in a conventional way not reaching miniaturization levels that were presented here. 

The lithium/iodine-poly-(2-vinyl pyridine) system has some unique properties. Its major application is in implantable medical devices such as cardiac pacemakers, which operate at a thermostatted 37°C [28], The reaction is... 

Lithium batteries are used in many portable consumer electronic devices and are also widely used in industry. The most common type of lithium cell used in consumer applications comprises metallic lithium as the anode and manganese dioxide as the cathode, with a Li salt such as Li perchlorate or Li tetrafluoroborate dissolved in an organic solvent. Lithium batteries find application in many long-life, critical devices such as cardiac pacemakers and other implantable electronic medical devices. These devices use special lithium-iodide batteries designed to last 15 years or more. Lithium batteries can be used in place of ordinary alkaline cells in many devices such as clocks and cameras. Although they are more expensive, lithium cells provide a much longer life, and thereby minimize battery replacement. 

Soon after the start of donepezil treatment three patients with Alzheimer s disease developed cardiac syncope (52). In two cases, a bradydysrhythmia was documented and pacemaker implantation was considered justified rather than donepezil withdrawal. 

Figure 3.35 Four sets of leads with basal ECG (left) and after pacemaker implantation in the RV (right) in a patient without ischaemic heart disease. Note the negative T wave in sinus rhythm complexes after implantation due to cardiac memory phenomenon. Characteristically, in case...

Gregoratos G, Abrams J, Epstein AE. ADD/AHA/NASPE 2002 guidelines update for implantation of cardiac pacemakers and antiarrhythmic... 

Previous coronary artery bypass graft surgery Mitral valve prolapse without valvar regurgitation Physiologic, functional, or innocent heart murmurs Previous Kawasaki disease without valvar dysfunction Previous rheumatic fever without valvar dysfunction Cardiac pacemakers (intravascular and epicardial) and implanted defibrillators... 

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