Arrhythmogenic

Antiarrhythmic treatment is based upon modulation of the ionic currents mentioned above. A principal problem with this therapy is that the electrophysiology of all cells is targeted and not specifically the arrhythmogenic focus. As a consequence, all antiar-rhythmics acting at transmembrane ionic channels possess a risk for elicitation of arrhythmia (= proar-rhythmic risk). 

Arrhythmogenic Right Ventricular Dysplasia/ Cardiomyopathy Aiteriogenesis Arteriosclerosis Arylhydrocarbon Receptor L-Ascorbic Acid ASF Family of Transporters Asn-linked Glycosylation ASON... 

MTX caused a contraction of vascular smooth muscle and positive inotropic, positive chronotropic and arrhythmogenic effects on cardiac muscle. The effect of MTX was little affected by various receptor blockers, a Na channel blocker or a catecholamine depleting agent. Further, MTX had no effect on the enzymes which were related to Ca movements, such as Na , K -ATPase, cyclic AMP phosphodiesterase, and sarcoplasmic reticulum Ca -ATPase. These results would eliminate the possible involvement of an indirect action elicited by the release of chemical mediators and direct modifications of their receptors, Na channels, or various enzymes as a major mechanism of action of MTX. 

In order to investigate which membrane currents underlie the changes in the action potential and the arrhythmogenic oscillatory after-depolarizations, we have... 

Benndorf, K., Friedrich, M. and Hirche, H. (1991). Reoxygenation-induced arrhythmogenic transient inward currents in isolated cells of the guinea-pig heart. Pflugers Arch. 418, 248-260. 

Fedida, D., Noble, D., Rankin, A.C. and Spindler, A.J. (1987). The arrhythmogenic transient inward current iTI and related contraction in isolated guinea-pig ventricular myocytes. J. Physiol. 392, 523-542. 

Use only one medication initially for rate or rhythm control. Occasionally, two agents may need to be utilized. Combination therapy may cause hypotension, bradycardia, and might be arrhythmogenic. 

Which of the following is an anti arrhythmic agent that has relatively few electro physiologic effects on normal myocardial tissue hut suppresses the arrhythmogenic tendencies of ischemic myocardial tissues ... 

Eger, E.I. No date. Report on arrhythmogenic and other effects of CH3CFCI2. Report to AlliedSignal Inc, Morristown, NJ. 

Recent concerns over the arrhythmogenic effects of a number of marketed compounds have resulted in the issue of the Points to Consider document, CPMP 986/96 by the EMA (European Medicines Agency) (available at http //www.eudra/org/humandocs/PDFs/SWP/098696en.pdf). 

Antzelevitch, C. (2004) Arrhythmogenic mechanisms of QT prolonging drugs is QT prolongation really the problem Journal of Electrocardiology, 37,... 

Preexisting cardiac disease Not recommended for use during the initial recovery phase of Ml. Trazodone may be arrhythmogenic in some patients. 

The more recent use of aggressive medical therapy with beta blockers, ACE-inhibitors, aspirin, and HMG Co A reductase inhibitors has had a profound benefit on those with coronary artery disease and reduced LVEF. To that end, revascularization still plays an important role in mortality reduction. In the Studies of Left Ventricular Dysfunction (SOLVD) database, CABG does improve survival compared to more modern use of medical therapy, with a 25% mortality risk reduction as well as an intriguing 46% risk reduction of sudden death [91]. This benefit improved as LVEF decreased, thus providing evidence that revascularization may stabilize heart function, reduce abnormal remodeling, and thus reduce the propensity to arrhythmogenicity. 

Myoblast therapy raises the possibility of arrhythmogenic effects. Consequently, many clinical studies require the placement of cardiac defibrillators in patients receiving myoblasts. 

Arrhythmogenic mechanisms of nonsedating antihistamines. Clinical and Experimental Allergy, 29 (Suppl 3), 174-181. 

Hi-receptor but also at muscarinic cholinoceptors, serotonin receptors, and adrenoceptors. This explains the atropine-like side effects of those drugs. The cationic amphophilic structure of these substances resemble that of antiarrhythmic agents which might explain the arrhythmogenic properties seen with some of these Hi-antagonists. 

Task Force of the Working Group on Arrhythmias of the European Society of Cardiology. The Sicilian gambit. A new approach to the classification of antiarrhythmic drugs based on their actions on arrhythmogenic mechanisms. Circulation 1991 84 1831-51. 

Halothane administration can result in a marked reduction in arterial blood pressure that is due primarily to direct myocardial depression, which reduces cardiac output. The fall in pressure is not opposed by reflex sympathetic activation, however, since halothane also blunts baroreceptor and carotid reflexes. Systemic vascular resistance is unchanged, although blood flow to various tissues is redistributed. Halothane also sensitizes the heart to the arrhythmogenic effect of catecholamines. Thus, maintenance of the patient s blood pressure with epinephrine must be done cautiously. 

Anti-yeast activity. Ethanol (100%) extract of the seed, on agar plate at a concentration of 18.7 mg/mL, was active on Candida albicans. Water extract of the seed, on agar plate was inactive on Candida albicans °b Arrhythmogenic effect. Hot water extract of the dried seed, administered orally to adults with cardiac abnormalities at a dose of 200 mg/person, produced equivocal effect . 

Arrhythmogenic effect. Water extract of the dried leaf, administered intravenously to cats at doses of 10-20 mg/kg, produced weak activity h... 

---