Cardiac flutter

Dlgltoxin. Digitoxin is a cardiac glycoside obtained from Digitalis purpurea. Digitoxin is indicated in the treatment of atrial flutter, atrial fibrillation, and supraventricular tachycardia. Its electrophysiologic and adverse effects are similar to those described for digoxin (87). 

The clinical indications of cardiac glycosides are tachyarrhythmic atrial fibrillation or flutter, as well as... 

The uses of the antiarrhythmic drug are given in the Summaiy Drug Table Antiarrhythmic Drug3. In general these drugp are used to prevent and treat cardiac arrhythmias, such as premature ventricular contractions (PVCs), ventricular tachycardia (VT), premature atrial contractions (PACs), paroxysmal atrial tachycardia (PAT), atrial fibrillation, and atrial flutter. Some of the antiarrhythmic dru are used for other... 

Many patients have a rhythm that varies between atrial flutter and AF. Atrial flutter is associated with a 40% higher risk of stroke. Given that the concordance of the AF and atrial flutter is high, anticoagulation should be considered in patients with atrial flutter and coexisting cardiac pathology predisposing to left atrial thrombus. 

EKGs taken on two workers about 2.5 hours after an acute exposure to hydrogen sulfide showed cardiac arrhythmias (Krekel 1964). The workers were exposed for <5 minutes after a spill of sodium sulfide that broke down to release hydrogen sulfide. In one individual, a negative P wave indicating a substitute rhythm was noted, while in the other individual a continuous arrhythmia due to atrial flutter was found. EKGs for both men had returned to normal within 24 hours. 

Cardiovascular manifestations include hypertension and cardiac arrhythmias (e.g., heart block, atrial flutter, paroxysmal atrial tachycardia, ventricular fibrillation, and digitalis-induced arrhythmias). In severe hypokalemia (serum concentration <2.5 mEq/L), ECG effects include ST-segment depression or flattening, T-wave inversion, and U-wave elevation. 

Indications for CG are (1) chronic congestive heart failure and (2) atrial fibrillation or flutter, where inhibition of AV conduction protects the ventricles from excessive atrial impulse activity and thereby improves cardiac performance (D). Occasionally, sinus rhythm is restored. 

Atrial flutter or fibrillation. An excessive ventricular rate can be decreased by verapamil (p. 122) or cardiac glycosides (p. 130). These drugs inhibit impulse propagation through the AV node, so that fewer impulses reach the ventricles. 

Class rv drugs block the slow inward Ca current (L-type calcium channel) in cardiac tissue. The most pronounced electrophysiological effects are exerted on cardiac cells that depend on the Ca" " channel for initiating the action potential, such as those found in the sinoatrial and A-V nodes. The administration of class IV drugs slows conduction velocity and increases refractoriness in the A-V node, thereby reducing the ability of the A-V node to conduct rapid impulses to the ventricle. This action may terminate supraventricular tachycardias and can slow conduction during atrial flutter or fibrillation. 

Contraindications Phenylephrine HCl injection should not be used with patients with severe hypertension, ventricular tachycardia or fibrillation, acute myocardial infarction (Ml), atrial flutter or fibrillation, cardiac arrhythmias, cardiac disease, cardiomyopathy, closed-angle glaucoma, coronary artery disease, patients who have a known hypersensitivity to phenylephrine, sulfites, or to any one of its components. 

Disturbances of cardiac rhythm (e.g., tachycardia, atrial fibrillation, ventricular flutter, and A-V or intraventricular block) are the most frequent causes of death. Thus, management of cardiac function is critical. If the patient survives the early phase, recovery without sequelae is probable, and vigorous resuscitative measures are important. A major clinical problem is determining when a patient is no longer in danger. Many patients with mild overdose have been hospitalized... 

The effects of disopyramide are very similar to those of procainamide and quinidine. Its cardiac antimuscarinic effects are even more marked than those of quinidine. Therefore, a drug that slows atrioventricular conduction should be administered with disopyramide when treating atrial flutter or fibrillation. 

Uses Rapid conversion of AF/arterial flutter Action Class IH andarrhythmic Dose Adults >60 kg. 0.01 mg/kg (max 1 mg) IV inf over 10 min may repeat x 1 <60 kg Use 0.01 mg/kg (ECC 2005 D/C cardioversion preferred) Caution [C, -] Contra w/ class I/EH andarrhythmics (Table VI-7) QTc >440 ms Disp Inj SE Arrhythmias, HA Interactions T Refractory effects W/ amiodarone, clisopyra-mide, procainamide, quinidine, sotalol T QT interval W/ andhistamines, andde-pressants, erythromycin, phenothiazines, TCAs EMS Use andhistamines w/ caudon, may T QT interval OD May cause increased repolarizadon leading to arrhythmias, bradycardia, hypotension leading to cardiac arrest symptomadc and suppordve... 

Quinidine is used for the maintenance of normal sinus rhythm in patients with atrial flutter or fibrillation. It is also used occasionally to treat patients with ventricular tachycardia. Because of its cardiac and extracardiac side effects, its use has decreased considerably in recent years and is now largely restricted to patients with normal (but arrhythmic) hearts. In randomized, controlled clinical trials, quinidine-treated patients are twice as likely to remain in normal sinus rhythm compared with controls. However, drug treatment was associated with a twofold to threefold increase in mortality. 

Tikosyn Dofetilide 125, 250, 500 (jig Capsule Maintenance of normal sinus rhythm and conversion of atrial fibrillation/ flutter Cardiac ion channel blocker/ antiarrhythmic drug MCC, corn starch, silicon dioxide, magnesium stearate Pfizer... 

Endogenous norepinephrine stimulates cardiac beta receptors. Receptor-linked cAMP-dependent protein kinases phosphorylate calcium channels to increase intracellular calcium. Elevated intracellular calcium increases conduction velocity (phase 0) and decreases the threshold potential in normal SA and AV node cells (see Figure 12.13). Beta blockers slow spontaneous conduction velocity in the SA node by approximately 10-20 percent. In addition, beta blockers can slow conduction velocity while increasing the refractory period of the AV node. These effects control the ventricular rate in atrial fibrillation or flutter and terminate paroxysmal supraventricular tachycardias. They are also safer, although somewhat less effective, than other drugs for suppression of premature ventricular complexes (PVCs). Drugs in this class approved by the FDA for treatment of various arrhythmias include propranolol, acebutolol, and esmolol. Problems with the beta blockers include drowsiness, fatigue, impotence, and depressed ventricular performance. 

Fibrillation, cardiac Heart flutter and irregular beats. 

The authors reviewed the biphasic effect of marijuana on the autonomic nervous system. At low to moderate doses it causes increased sympathetic activity, producing a tachycardia and increase in cardiac output blood pressure therefore increases. At high doses it causes increased parasympathetic activity, leading to bradycardia and hypotension. They thought that this patient most probably had adrenergic atrial flutter. 

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