Arrhythmia detection system

Tisdale JE. Arrhythmias. In Tisdale JE, Miller DA, eds. Drug-Induced Diseases. Prevention, Detection and Management. Bethesda, MD American Society of Health-Systems Pharmacists 2005 289-327. 

Cardiovascular Effects. Most studies of humans exposed to carbon tetrachloride by inhalation have not detected significant evidence of cardiovascular injury, even at exposure levels sufficient to markedly injure the liver and/or kidney. Changes in blood pressure, heart rate, or right- sided cardiac dilation have sometimes, but not always, been observed (Ashe and Sailer 1942 Guild et al. 1958 Kittleson and Borden 1956 Stewart et al. 1961 Umiker and Pearce 1953), and are probably secondary either to fluid and electrolyte retention resulting from renal toxicity, or to central nervous system effects on the heart or blood vessels. Carbon tetrachloride also may have the potential to induce cardiac arrhythmias by sensitizing the heart to epinephrine, as has been reported for various chlorinated hydrocarbon propellants (Reinhardt et al. 1971). 

The heart is an electromechanical system, in which mechanical pumping function is initiated and coordinated by automatic rhythmic cardiac electrical activity. Transient electrical disturbances m this activity (cardiac arrhythmias) can immediately cause death. The implantable cardioverter defibrillator (ICD) is a medical device that can be implanted in a human body and will automatically detect and treat cardiac arrhythmias. Mirowski et al. [1] first reported on a demonstration of a functioning ICD in 1970. In his demonstration, he induced a fatal ventricular tachyarrhythmia in a dog. The dog was then successfully and dramatically rescued by the automatic operation of a previously implanted ICD. The first report of successful ICD implantation in humans soon followed [2]. In subsequent decades, advances in ICD technology have reduced ICD size from more than 200 cm, originally, to as httle as 25 cm, while markedly improving functionality, reliability, and longevity. ICDs are now considered as standard of care for patients at risk for ventricular arrhythmia and are implanted in more than 150,000 patients per year in the United States alone [3]. 

Biological and physiological systems are typical complex systems, which provide examples of aperiodicity and chaos [1-7]. Aperiodic cardiac oscillations are reflected in ECG for different cases of arrhythmia Fig. (12.1). Similarly, chaotic, aperiodic and noisy oscillations are observed in EEC in specific cases as shown in Fig. (12.2). Closely allied with chemical oscillations are membrane oscillations which have considerable relevance in physiological processes including neurological and cardiac disorders in the context of detection and control. 

An ICD has a programmable pulse generator and lead system that monitors the heart s activity, detects ventricular arrhythmias and other tachyarrhythmias, and responds with appropriate therapies. 

An implantable cardioverter-defibrillator (ICD) has a programmable pulse generator and lead system that monitors the heart s activity, detects ventricular arrhythmias and other tachyarrhythmias, and responds with appropriate therapies. The range of therapies includes antitachycardia and antibradycardia pacing, cardioversion, and defibrillation. Newer defibrillators can also pace both atrium and ventricle. 

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