Arrhythmias definition

On the basis of two large randomized trials aimed at suppressing premature ventricular complexes after MI, so-called warning arrhythmias, it was discovered that many common antiarrhythmic medications actually increase the risk of mortality [20, 21]. Amiodarone also has been shown to have no definitive effect on mortality in patients after an MI, including in the recent SCD-HeFT trial [22-24]. In fact, of all antiarrhythmic medications, only beta blockers have been clearly shown to prevent SCD after MI [25], particularly among those with depressed LV function [11]. 

The benefits of antiarrhythmic therapy are actually relatively difficult to establish. Two types of benefits can be envisioned reduction of arrhythmia-related symptoms, such as palpitations, syncope, or cardiac arrest or reduction in long-term mortality in asymptomatic patients. Among drugs discussed here, only 3 blockers have been definitely associated with reduction of mortality in relatively asymptomatic patients, and the mechanism underlying this effect is not established (see Chapter 10). 

Flecainide slows conduction in all cardiac cells including the anomalous pathways responsible for the Wolff-Parkinson-White (WPW) syndrome. Together with encainide and moricizine, it underwent clinical trials to establish if suppression of asymptomatic premature beats with antiarrhythmic drugs would reduce the risk of death from arrhythmia after myocardial infarction. The study was terminated after preliminary analysis of 1727 patients revealed that mortality in the groups treated with flecainide or encainide was 7.7% compared with 3.0% in controls. The most likely explanation for the result was the induction of lethal ventricular arrhythmias possibly due to ischaemia by flecainide and encainide, i.e. a proarrhythmic effect. In the light of these findings the indications for flecainide are restricted to patients with no evidence of structural heart disease. The most common indication, indeed where it is the drug of choice, is atrioventricular re-entrant tachycardia, such as AV nodal tachycardia or in the tachycardias associated with the WPW syndrome or similar conditions with anomalous pathways. This should be as a prelude to definitive treatment with radiofrequency ablation. Flecainide may also be useful in patients with paroxysmal atrial fibrillation. 

Studies of chronic exposure of those working in dry cleaning plants have reported some CNS effects, some liver function abnormalities, renal dysfunction, and some definite central and peripheral neurotoxicity. Other effects from chronic exposure to PERC include cardiac arrhythmias, reduced color perception, impaired memory, peripheral neuropathy, impaired vision, confusion, disorientation, fatigue, personality changes, and agitation. 

Cleland, J. G., N. Freemantle, G. Kaye, M. Nasir, P. Velavan, K. Lalukota, et al. (2004). Clinical trials update from the American Heart Association meeting Omega-3 fatty acids and arrhythmia risk in patients with an implantable defibrillator, ACTIV in CHF, VALIANT, the Hanover autologous bone marrow transplantation study, SPORTIF V, ORBIT and PAD and DEFINITE. Eur J Heart Fail 6(1) 109-15. 

These seem to be the first documented reports of cardiac arrhythmias that can definitely be attributed to phenol in... 

The common ventricular arrhythmias include (1) premature ventricular complexes (PVCs), (2) ventricular tachycardia, and (3) ventricular fibrillation. Again, these arrhythmias may result in a wide variety of symptoms. PVCs often cause no symptoms or only mild palpitations. Ventricular tachycardia may be a life-threatening situation associated with hemodynamic collapse or be totally asymptomatic. Ventricular fibrillation, by definition, is an acute medical emergency necessitating cardiopulmonary resuscitation (CPR). 

Niacin in the CDP significantly reduced definite, nonfatal MI as compared with placebo (10.1% versus 13.9%), whereas clofibrate did not reduce death from any cause or nonfatal or fatal MI at the 5-year follow-up period. Clofibrate did increase the rate of definite or suspected fatal or nonfatal pulmonary embolism or thrombophlebitis compared with placebo (5.8% versus 3.6%) after adjusting for baseline characteristics for total follow-up. Other findings with clofibrate that occurred more frequently than with placebo included intermittent claudication, arrhythmias, palpable spleen, cholelithiasis (including cholecystectomy), and more frequent use of anticoagulants. Skin reactions, gastrointestinal complaints, and the use of gout... 

Definition Commercial prod. Is the monohydrate Empiricai C2K2O4 C2K2O4 H2O Formuia (COOK)2 H2O Properties M.w. 166.22 Monohydrate Colorless transparent cryst. odorless sol. in water efflorescent in warm dry air dec. when heated m.w. 184.24 dens. 2.13 loses water 160 C Toxicoiogy LDLo (oral, woman) 1 g/kg toxic by inh. and ing. human systemic effects by ing. (cardiac arrhythmias, shock, Gl changes) ... 

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