Cardiac electrophysiology

The cardiac cycle in the normal human heart is initiated by the sinoatrial (SA) node. The excitation wave spreads through the atria at a velocity of about 1 m/s. The electroanatomy of the heart separates the atria and ventricles (two-chamber heart) so that the excitatory wave can be delayed before it reaches the ventricles. This delay of about 0.15 s is performed in the zone of the atrioventricular (AV) node, and permits a filling of the 

Important clinical use of ECG data is to look for beat-to-beat differences, both waveform and repetition rate (variation in the beat-to-beat Q-T interval is called dispersion), arrhythmias, blocks, detection of ischemia, and infarcted muscle volumes and their positions. 

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T. G. (2003) Relationships between predinical cardiac electrophysiology, clinical QT interval prolongation and torsade de pointes for a broad range of drugs evidence for a provisional safety margin in drug development. Cardiovascular Research, 58, 32-45. 

Hammond, T.G., Carlsson, L., Davis, A. S., Lynch, W.G., MacKenzie, I., Redfern, W.S., Sullivan, A.T. and Camm, A.J. (2001) Methods of collecting and evaluating non-clinical cardiac electrophysiology data in the pharmaceutical industry results of an international survey. Cardiovascular Research, 49, 741-750. 

Abi-Gerges, N., Philp, K., Pollard, C., Wakefield, I., Hammond, T., and Valentin, J.P., Sex differences in ventricular repolarization from cardiac electrophysiology to Torsades de Pointes, Fund. Clin. Pharmacol., 18, 139-151, 2004. 

Zian H. Tseng, MD, MAS Cardiac Electrophysiology Section, Department of Medicine, University of California, San Francisco, CA, USA... 

Benditt DG, Sakaguchi S, Goldstein MA, et al. Sinus node dysfunction, pathophysiology, clinical features, evaluation, and treatment. In Zipes DP, Jalife J, eds. Cardiac electrophysiology from cell to bedside. 2nd ed. Philadelphia WB Saunders, 1995 1215-47. 

TABLE 16.2 Cardiac Electrophysiological Effects of Class I Antiarrhythmic Drugs... 

Table 16.2 describes the direct, indirect, and net actions of procainamide on cardiac electrophysiology. 

Table 16.3 summarizes the cardiac electrophysiological effects of class II, III, and IV agents, and Table 16.4 summarizes the actions of the (3-receptor blocking agents... 

Ibutilide (Corvert) is a structural analog of sotalol and produces cardiac electrophysiological effects similar to those of the antiarrhythmic agents in class III. 

Beyer EC, Veenstra RD, Kanter HL, Saffitz JE Molecular structure and patterns of expression of cardiac gap junction proteins. In Zipes D, Jalife J (eds) Cardiac electrophysiology. From cell to bedside. 2nd ed. WB Saunders, Philadelphia, 1995, pp 31-38. 

Spach MS, Dolber PC Discontinuous anisotropic propagation in Rosen MR, Janse MJ, Wit AL (eds) Cardiac Electrophysiology A Textbook. Mount Kisco, Futura, 1990, pp 517-534. 

When I started as a novice in the field of cardiac electrophysiology, the dogma was that gap junctions are specialized membrane structures present in the cardiac and smooth muscle of vertebrates where they serve to propagate the action potential from cell to cell. Purkinje fibers and muscular trabeculae were the preferred cardiac preparations. These multicellular preparations were suitable to perform cable analyses and diffusion studies. At that time, my mentor, Silvio Weidmann, had already accomplished his elegant functional studies. 

One important implication of this increasingly complex view of the molecular basis of cardiac electrophysiology is that variations in many genes may... 

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